{"id":410,"date":"2023-06-23T14:52:09","date_gmt":"2023-06-23T18:52:09","guid":{"rendered":"https:\/\/opentextbooks.concordia.ca\/explorationsclone\/chapter\/13\/"},"modified":"2026-01-30T17:48:43","modified_gmt":"2026-01-30T22:48:43","slug":"13","status":"publish","type":"chapter","link":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/chapter\/13\/","title":{"raw":"Race and Human Variation","rendered":"Race and Human Variation"},"content":{"raw":"<div class=\"__UNKNOWN__\">\r\n<p class=\"import-Normal\">Michael B. C. Rivera, Ph.D., University of Cambridge<\/p>\r\n<p class=\"import-Normal\"><em>This chapter is a revision from <\/em><em>\"<\/em><a class=\"rId7\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-12\/\"><em>Chapter 13: Race and Human Variation<\/em><\/a><em>\u201d by Michael B. C. Rivera. In <\/em><a class=\"rId8\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\"><em>Explorations: An Open Invitation to Biological Anthropology, first edition<\/em><\/a><em>, edited by Beth Shook, Katie Nelson, Kelsie Aguilera, and Lara Braff, which is licensed under <\/em><a class=\"rId9\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\"><em>CC BY-NC 4.0<\/em><\/a><em>. <\/em><\/p>\r\n\r\n<div class=\"textbox textbox--learning-objectives\"><header class=\"textbox__header\">\r\n<h2 class=\"textbox__title\"><span style=\"color: #000000\">Learning Objectives<\/span><\/h2>\r\n<\/header>\r\n<div class=\"textbox__content\">\r\n<ul>\r\n \t<li>Illustrate the troubling history of \u201crace\u201d concepts.<\/li>\r\n \t<li>Explain human variation and evolution as the thematic roots of biological anthropology as a discipline.<\/li>\r\n \t<li>Critique earlier \u201crace\u201d concepts based on a contemporary understanding of the apportionment of human genetic variation.<\/li>\r\n \t<li>Explain how biological variation in humans is distributed clinally and in accordance with both isolation-by-distance and Out-of-Africa models.<\/li>\r\n \t<li>Identify phenotypic traits that reflect selective and neutral evolution.<\/li>\r\n \t<li>Extend this more-nuanced view of human variation to today\u2019s research, the implications for biomedical studies, applications in forensic anthropology, and other social\/cultural\/political concerns.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\nHumans exhibit biological variation. Humans also have a universal desire to categorize other humans in order to make sense of the world around them. Since the birth of the discipline of <strong>[pb_glossary id=\"2080\"]biological anthropology[\/pb_glossary], <\/strong>we have been interested in studying how humans vary biologically and what the sources of this variation are. Before we tackle these big problems, first consider this question: Why <em>should<\/em> we study human variation?\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"429\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2023\/06\/image26-3.png\" alt=\"Culturally and biologically diverse humans.\" width=\"429\" height=\"429\" \/> Figure 14.1: Humans are culturally diverse (in that cultural differences contribute to a great degree of variation between individuals), but those shown are genetically undiverse. (Top left: Hadzabe members in Tanzania; top right: Inuit family; bottom left: Andean man in Peru; bottom right: English woman.) Credit: <a class=\"rId11\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-12\/\">Humans are diverse (Figure 13.1)<\/a> original to <a class=\"rId12\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Michael Rivera is a collective work under a <a class=\"rId13\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA 4.0<\/a> license. [Includes <a class=\"rId14\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Tanzania_-_Hadzabe_hunter_(14533536392).jpg\">Tanzania - Hadzabe hunter (14533536392)<\/a> by <a class=\"rId15\" href=\"https:\/\/www.flickr.com\/people\/67947877@N06\">A_Peach<\/a>, <a class=\"rId16\" href=\"https:\/\/creativecommons.org\/licenses\/by\/2.0\/legalcode\">CC BY 2.0<\/a>; <a class=\"rId17\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Inuit-Kleidung_1.jpg\">Inuit-Kleidung 1<\/a> by Ansgar Walk, <a class=\"rId18\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0<\/a>; <a class=\"rId19\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Andean_Man.jpg\">Andean Man<\/a> by <a class=\"rId20\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Cacophony\">Cacophony<\/a>, <a class=\"rId21\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0<\/a>; <a class=\"rId22\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Jane_Goodall_GM.JPG\">Jane Goodall GM<\/a> by <a class=\"rId23\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Floatjon\">Floatjon<\/a>, <a class=\"rId24\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">There are certainly academic reasons for studying human variation. First, it is highly interesting and important to consider the evolution of our species (see Chapters 9\u201312) and how our biological variation may be similar to (or different from) that of other species (e.g., other primates and apes; see Chapters 5 and 6). Second, anthropologists study modern human variation to understand how different biological traits developed over evolutionary time (see Figure 14.1). Suppose we are able to grasp the evolutionary processes that produce the differences in biology, physiology, body chemistry, behavior, and culture (<strong>[pb_glossary id=\"804\"]human variation[\/pb_glossary]<\/strong>). In that case, we can make more accurate inferences about evolution and adaptation among our hominin ancestors, complementing our study of fossil evidence and the archaeological record. Third, as will be discussed in more detail later on, it is important to consider that biological variation among humans has biomedical, forensic, and sociopolitical implications. For these reasons, the study of human variation and evolution has formed the basis of anthropological inquiry for centuries and continues to be a major source of intrigue and inspiration for scientific research conducted today.<\/p>\r\n<p class=\"import-Normal\">An even-more-important role of the biological anthropologist is to improve public understanding of human evolution and variation\u2014outside of academic circles. Terms such as <strong>[pb_glossary id=\"2090\"]race[\/pb_glossary]<\/strong> and <strong>[pb_glossary id=\"2091\"]ethnicity[\/pb_glossary]<\/strong> are used in everyday conversations and in formal settings within and outside academia. The division of humankind into smaller, discrete categories is a regular occurrence in day-to-day life. This can be seen regularly when governments acquire census data with a heading like \u201cgeographic origin\u201d or \u201cethnicity.\u201d Furthermore, such checkboxes and drop-down lists are commonly seen as part of the identifying information required for surveys and job applications.<\/p>\r\n<p class=\"import-Normal\">According to professors of anthropology, ethnic studies, and sociology, race is often understood as rooted in biological differences, ranging from such familiar traits as skin color or eye shape to variations at the genetic level. However, race can also be studied as an \u201cideological construct\u201d that goes beyond biological and genetic bases (Fuentes et al. 2019), at different times relating to our ethnicities, languages, religious beliefs, and cultural practices. Sometimes people associate racial identity with the concept of socioeconomic status or position, or they link ideas about race to what passport someone has, how long they have been in a country, or how well they have \u201cintegrated\u201d into a population.<\/p>\r\n<p class=\"import-Normal\">Some of these ideas about ethnicity have huge social and political impacts, and notions of race have been part of the motivation behind various forms of racism and prejudice today, as well as many wars and genocides throughout history. [pb_glossary id=\"2082\"]<strong>Racism<\/strong>[\/pb_glossary] manifests in many ways\u2014from instances of bullying between kids on school playgrounds to underpaid minorities in the workforce, and from verbal abuse hurled at people of color to violent physical behaviors against those of a certain race. [pb_glossary id=\"2083\"]<strong>Prejudice<\/strong>[\/pb_glossary] can be characterized as negative views toward another group based on some perceived characteristic that makes all members of that group worthy of disdain, disrespect, or exclusion (not solely along racial lines but also according to [dis]ability, gender, sexual orientation, or socioeconomic background, for example). According to Shay-Akil McLean (2014), \u201cRacism is not something particular to the United States and race is not the same everywhere in the world. Racial categories serve particular contextual purposes depending on the society they are used in, but generally follow the base logic of the supremacy of one type of human body over all others (ordering these human bodies in a hierarchical fashion).\u201d Choosing which biological or nonbiological features to use when discussing race is always a social process (Omi and Winant 2014). Race concepts have no validity to them unless people continue to use them in their daily lives\u2014and, in the worst cases, to use them to justify racist behaviors and problematic ideas about racial difference or superiority\/inferiority. Recent work in anthropological genetics has revealed the similarities amongst humans on a molecular level and the relatively few differences that exist between populations (Omi and Winant 2014).<\/p>\r\n<p class=\"import-Normal\">The role of the biological anthropologist becomes crucial in the public sphere, because we may be able to debunk myths surrounding human variation and shed light, for the nonanthropologists around us, on how human variation is actually distributed worldwide (see Figure 14.1). Rooted in scientific observations, our work can help nonanthropologists recognize how common ideas about \u201crace\u201d often have no biological or genetic basis. Many anthropologists work hard to educate students on the history of where race concepts come from, why and how they last in public consciousness, and how we become more conscious of racial issues and the need to fight against racism in our societies. Throughout this chapter, I will highlight how humans cannot actually be divided into discrete \u201craces,\u201d because most traits vary on a continuous basis and human biology is, in fact, very [pb_glossary id=\"2087\"]<strong>homogenous<\/strong>[\/pb_glossary] compared to the greater genetic variation we observe in closely related species. Molecular anthropology, or anthropological genetics, continues to add new layers to our understanding of human biological variation and the evolutionary processes that gave rise to the contemporary patterns of human variation. The study of human variation has not always been unbiased, and thinkers and scientists have always worked in their particular sociohistorical context. For this reason, this chapter opens with a brief overview of race concepts throughout history, many of which relied on unethical and unscientific notions about different human groups.<\/p>\r\n\r\n<\/div>\r\n<div class=\"textbox\">\r\n<h2 class=\"import-Normal\">Special Topic: My Experiences as an Asian Academic<\/h2>\r\n[caption id=\"\" align=\"aligncenter\" width=\"578\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image10-4.jpg\" alt=\"Outdoor photo of this chapter\u2019s author.\" width=\"578\" height=\"433\" \/> Figure 14.2: Michael B. C. Rivera in Hong Kong. Credit: Michael B. C. Rivera in Hong Kong original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) is under a <a class=\"rId26\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\nMy name is Michael, and I am a biological anthropologist and archaeologist (Figure 14.2). What strikes me as most interesting to investigate is human biological variation today and the study of past human evolution. For instance, some of my research on ancient coastal populations has revealed positive effects of coastal living on dietary health and many unique adaptations in bones and teeth when living near rivers and beaches. I love talking to students and nonscientists about bioanthropologists\u2019 work, through teaching, science communication events, and writing book chapters like this one. I grew up in Hong Kong, a city in southern China. My father is from the Philippines and my mother is from Hong Kong, which makes me a mixed Filipino-Chinese academic. Growing up, I noticed that people came in all shapes, sizes, and colors. My life is very different now in that I have gained the expertise to explain those differences, and I feel a great responsibility to guide those new to anthropology toward their own understandings of diversity.\r\n<p class=\"import-Normal\">Biological anthropology is not taught extensively in Hong Kong, so I moved to the United Kingdom to earn my bachelor\u2019s, master\u2019s, and doctorate degrees. It was fascinating to me that we could answer important questions about human variation and history using scientific methods. However, I did not have many minority academic role models to look up to while I was at university. My department was made up almost exclusively of white westerner faculty, and it was hard to imagine I could one day get a job at these western institutions. While pursuing my degrees, I also remember several instances of my research contributions being overlooked or dismissed. Sometimes professors and fellow students would make racist comments toward Asian scholars (including me) and other Black, Indigenous and researchers of color, making us greatly uncomfortable in those spaces. When one of us would work up the courage to tell university leaders our experiences of being stereotyped, dismissed, or insulted, we received little support and were further excluded from research and teaching activities. This is a common experience for Black, Indigenous, and other people of color who pursue biological anthropology, and we face the difficult choice between leaving the field or bearing with such unsafe spaces.<\/p>\r\n<p class=\"import-Normal\">It became important to me at that time to find other academics of color with whom to share experiences and form community. I feel inspired by all my colleagues who advocate for greater representation and diversity in universities (whether they are minority academics or not). I admire many of my fellow researchers who are underrepresented and do a great job of representing minority groups through their cutting-edge research and quality teaching at the undergraduate and graduate levels. Although I no longer work in the West, it has remained my great hope that those in the West and the \u201cGlobal North\u201d will continue to improve university culture, and I support any efforts there to welcome all scholars.<\/p>\r\n<p class=\"import-Normal\">My current work is based in Hong Kong, where I am deeply dedicated to helping develop biological anthropology in East and Southeast Asia and promoting research from our home regions on the international scene. The study of anthropology really highlights how we share a common humanity and history. Being somebody who is \u201cmixed race\u201d and Asian likely played a key role in steering me toward the study of human variation. As this chapter hopefully shows, there is a lot to discuss about race and ethnicity regarding the discipline\u2019s history and current understandings of <strong>[pb_glossary id=\"2084\"]human diversity[\/pb_glossary]<\/strong>. Some scientific and technological advancements today are misused for reasons to do with money, politics, or the continuation of antiquated ideas. It is my belief, alongside many of my friends and fellow anthropologists, that science should be more about empathy toward all members of our species and contributing to the intellectual and technological nourishment of society. After speaking to many members of the public, as well as my own undergraduate students, I have received lovely messages from other individuals of color expressing thanks and appreciation for my presence and understanding as a minority scientist and mentor figure. Anthropology needs much more diversity as well as to make room for those who have traveled different routes into the discipline. All paths taken into anthropology are valid and valuable. I would encourage everyone to study anthropology\u2014it is a field for understanding and celebrating the intricacies of human diversity.<\/p>\r\n\r\n<\/div>\r\n<div class=\"__UNKNOWN__\">\r\n<h2 class=\"import-Normal\">The History of \"Race\" Concepts<\/h2>\r\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d in the Classical Era<\/strong><\/h3>\r\n[caption id=\"\" align=\"alignleft\" width=\"435\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image11-8.png\" alt=\"Painting of four individuals with varied skin colors, head hair, facial hair, and clothing styles.\" width=\"435\" height=\"331\" \/> Figure 14.3: (From left to right) Depicting a Berber (Libyan), a Nubian, an Asiatic (Levantine), and an Egyptian, copied from a mural on the tomb of Seti I. Credit: Egyptian races drawing by Heinrich von Minutoli (1820) of a mural by an unknown artist from the tomb of Seti I is in the public domain.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The earliest classification systems used to understand human variation are evidenced by ancient manuscripts, scrolls, and stone tablets recovered through archaeological, historical, and literary research. The Ancient Egyptians had the <em>Book of Gates<\/em>, dated to the New Kingdom between 1550 B.C.E. and 1077 B.C.E (Figure 14.3). In one part of this tome dedicated to depictions of the underworld, scribes used pictures and hieroglyphics to illustrate a division of Egyptian people into the four categories known to them at the time: the Aamu (Asiatics), the Nehesu (Nubians), the Reth (Egyptians), and the Themehu (Libyans). Though not rooted in any scientific basis like our current understandings of human variation today, the Ancient Egyptians believed that each of these groups were made of a distinctive category of people, distinguishable by their skin color, place of origin, and even behavioral traits.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Another well-known early document is the Bible, where it is written that all humankind descends from one of three sons of Noah: Shem (the ancestor to all olive-skinned Asians), Japheth (the ancestor to pale-skinned Europeans), and Ham (the ancestor to darker-skinned Africans). Similar to the Ancient Egyptians, these distinctions were based on behavioral traits and skin color. More recent work in historiography and linguistics suggest that the branches of \u201cHamites,\u201d \u201cJaphethites,\u201d and \u201cShemites\u201d may also relate to the formation of three independent language groups some time between 1000 and 3000 B.C.E. With the continued proliferation of Christianity, this concept of approximately three racial groupings lasted until the Middle Ages and spread as far across Eurasia as crusaders and missionaries ventured at the time.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"309\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image9-9.png\" alt=\"Rows of organisms, with plants and animals at the bottom and humans, angels, and God at top.\" width=\"309\" height=\"449\" \/> Figure 14.4: The Great Chain of Being from the Rhetorica Christiana by Fray Diego de Valades (1579). Credit: Great Chain of Being 2 by Didacus Valades (Diego Valades 1579) and photographed by Rhetorica Christiana (via Getty Research) is in the public domain.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">There is also the \u201cGreat Chain of Being,\u201d conceived by ancient Greek philosophers like Plato (427\u2012348 B.C.E.) and Aristotle (384\u2012322 B.C.E.). They played a key role in laying the foundations of empirical science, whereby observations of everything from animals to humans were noted with the aim of creating taxonomic categories. Aristotle describes the Great Chain of Being as a ladder along which all objects, plants, animals, humans, and celestial bodies can be mapped in an overall hierarchy (in the order of existential importance, with humans placed near the top, just beneath divine beings; see Figure 14.4). When he writes about humans, Aristotle expressed the belief that certain people are inherently (or genetically) more instinctive rulers, while others are more natural fits for the life of a worker or enslaved person. Based on research by biological anthropologists, we currently recognize that these early systems of classification and hierarchization are unhelpful in studying human biological variation. Both behavioral traits and physical traits are coded for by multiple genes each, and how we exhibit those traits based on our genetics can vary significantly even between individuals of the same population.<\/p>\r\n\r\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d during the Scientific Revolution<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The 1400s to 1600s saw the beginnings of the <strong>[pb_glossary id=\"2085\"]Scientific Revolution[\/pb_glossary]<\/strong> in Western societies, with thinkers like Nicholas Copernicus, Galileo Galilei, and Leonardo Da Vinci publishing some of their most important findings. While by no means the first or only scholars globally to use observation and experimentation to understand the world around them, early scientists living at the end of the medieval period in Europe increasingly employed more experimentation, quantification, and rational thought in their work. This is the main difference between the work of the ancient Egyptians, Romans, and Greeks and that of later scientists such as Isaac Newton and Carl Linnaeus in the 1600s and 1700s.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"215\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image24-2.png\" alt=\"Historic painting of a man in 18th-century wig and garments.\" width=\"215\" height=\"259\" \/> Figure 14.5: Carl Linnaeus. Credit: <a class=\"rId35\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Carl_von_Linn%C3%A9.png\">Carl von Linn\u00e9<\/a> by <a class=\"rId36\" href=\"https:\/\/en.wikipedia.org\/wiki\/en:Alexander_Roslin\">Alexander Roslin<\/a> (1718-1793) is in the <a class=\"rId37\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Linnaeus is the author of <em>Systema Naturae<\/em> (1758), in which he classified all plants and animals under the formalized naming system known as[pb_glossary id=\"1985\"] <strong>binomial nomenclature<\/strong>[\/pb_glossary] (Figure 14.5). This system is <strong>[pb_glossary id=\"2093\"]typological[\/pb_glossary]<\/strong>, in that organisms are placed into groups according to how they are similar or different to others under study. What was most anthropologically notable about Linnaeus\u2019s typological system was that he was one of the first to group humans with apes and monkeys, based on the anatomical similarities between humans and nonhuman primates. However, Linnaeus viewed the world in line with <strong>[pb_glossary id=\"2094\"]essentialism[\/pb_glossary]<\/strong>, a problematic concept that dictates that there are a unique set of characteristics that organisms of a specific kind <em>must<\/em> have and that would remove organisms from taxonomic categorizations if they lacked any of the required criteria.<\/p>\r\nLinnaeus subdivided the human species into four varieties, with overtly racist categories based on skin color and \u201cinherent\u201d behaviors. Some European scientists during this period were not aware of their own biases skewing their interpretations of biological variation, while others deliberately worked to shape public perceptions of human variation in ways that established \u201c<strong>[pb_glossary id=\"2095\"]otherness[\/pb_glossary]<\/strong>\u201d and enforced European domination and the subordination of non-European people. The conclusions and claims at which they arrived, consciously or subconsciously, often fit the times they were living through\u2014the so-called <strong>[pb_glossary id=\"2097\"]Age of Discovery[\/pb_glossary]<\/strong>, when the superiority of European cultures over others was a pervasive idea throughout people\u2019s social and political lives. Although much of Eurasia was linked by spice- and silk-trading routes, the European colonial period between the 1400s and 1700s was marked by many new and unfortunately violent encounters overseas (Figure 14.6). When Europeans arrived by ship on the shores of continents that were already inhabited, it was their first meeting with the Indigenous peoples of the Americas and Australasia, who looked, spoke, and behaved differently from peoples with whom they were familiar. Building on the idea of species and \u201csubspecies,\u201d natural historians of this time invented the term <em>race<\/em>, from the French <em>rasse<\/em> meaning \u201clocal strain.\u201d\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"421\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image25-4.png\" alt=\"Spanish explorers with their military and religious gear surrounding indigenous people.\" width=\"421\" height=\"273\" \/> Figure 14.6: A painting depicting the colonization of the Mississippi River environs by Spaniard Hernando DeSoto in 1541 (painted in 1853 by William H. Powell). Credit: <a class=\"rId39\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Discovery_of_the_Mississippi.jpg\">Discovery of the Mississippi<\/a> by <a class=\"rId40\" href=\"https:\/\/en.wikipedia.org\/wiki\/en:William_Henry_Powell\">William Henry Powell<\/a> (photograph courtesy of <a class=\"rId41\" href=\"https:\/\/en.wikipedia.org\/wiki\/Architect_of_the_Capitol\">Architect of the Capitol<\/a>) is in the <a class=\"rId42\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\">Another scientist of the times, Johann Friedrich Blumenbach (1752\u20121840), classified humans into five races based on his observations of cranial form variation as well as skin color. He thus dubbed the \u201coriginal\u201d form of the human cranium the \u201cCaucasian\u201d form, with the idea that the ideal climate conditions for early humans would have been in the Caucasus region near the Caspian Sea. The key insight Blumenbach presented was that human variation in any particular trait should be more accurately viewed as falling along a gradation (Figure 14.7). While some of his theories were correct according to what we observe today with more knowledge in genetics, they erroneously believed that human \u201csubspecies\u201d were \u201cdegenerated\u201d or \u201ctransformed\u201d varieties of an ancestral Caucasian or European race. According to them, the Caucasian cranial dimensions were the least changed over human evolutionary time, while the other skull forms represented geographic variants of this \u201coriginal.\u201d As will be discussed in greater detail later in this chapter, we have genetic and craniometric evidence for sub-Saharan Africa being the origin of the human species instead (see Chapter 12 on the fossil record that places the origins of modern <em>Homo sapiens<\/em> in north and east Africa). Based on work that shows how most biological characteristics are coded for by nonassociated genes, it is not reasonable to draw links between individuals\u2019 personalities and their skull shapes.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"686\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image7-10.png\" alt=\"Historic drawing of five skulls.\" width=\"686\" height=\"259\" \/> Figure 14.7: Five skull drawings representing specimens for Blumenbach\u2019s \u201cMongolian,\u201d \u201cAmerican,\u201d \u201cCaucasian,\u201d \u201cMalayan,\u201d and \u201cAethiopian\u201d races. Credit: <a class=\"rId44\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Blumenbach's_five_races.JPG\">Blumenbach's five races<\/a> by Johann Friedrich Blumenbach is in the <a class=\"rId45\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>. Original in the 1795 Treatise on \"De generis humani varietate nativa,\" unnumbered page at the end of the book titled \"Tab II\".[\/caption]\r\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d and the Dawn of Scientific Racism<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Between the 1800s and mid-1900s, and contrary to what you might expect, an increased use of scientific methods to justify racial schemes developed in scholarship. Differing from earlier views, which saw all humans as environmentally deviated from one \u201coriginal\u201d humankind, classification systems after 1800 became more [pb_glossary id=\"2098\"]<strong>polygenetic<\/strong> [\/pb_glossary](viewing all people as having separate origins) rather than [pb_glossary id=\"2099\"]<strong>monogenetic<\/strong>[\/pb_glossary] (viewing all people as having a single origin). Instead of moving closer to our modern-day understandings of human variation, there was increased support for the notion that each race was created separately and with different attributes (intelligence, temperament, and appearance).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The 1800s were an important precursor to modern biological anthropology as we know it, given that this was when the scientific measurement of human physical features (anthropometry) truly became popularized. However, empirical studies in the 1800s pushed even further the idea that Europeans were culturally and biologically superior to others. While considered one of the pioneers of American \u201cphysical\u201d anthropology, Samuel George Morton (1799\u20121851) was a scholar who had a large role in perpetuating 1800s scientific racism. By measuring cranial size and shape, he calculated that \u201cCaucasians,\u201d on average, have greater cranial volumes than other groups, such as the Indigenous peoples of the Americas and peoples Morton referred to collectively as \u201cNegros.\u201d Today, we know that cranial size variation depends on such factors as Allen\u2019s and Bergmann\u2019s rules, which give a more likely explanation: in colder environments, it is advantageous for those living there to have larger and rounder heads because they conserve heat more effectively than more slender heads (Beals et al. 1984). The leading figures in craniometry during the 1800s instead were linked heavily with powerful individuals and wealthy sociopolitical institutions and financial bodies. Theories in support of hierarchical racial schemes using \u201cscientific\u201d bases certainly helped continue the exploitative and unethical trafficking and enslavement of Africans between the 1500s and 1800s.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Morton went on to write in his publication <em>Crania Americana<\/em> (1839) a number of views that fit with a concept called [pb_glossary id=\"2100\"]<strong>biological determinism<\/strong>[\/pb_glossary]. The idea behind biological determinism is that an association exists between people\u2019s physical characteristics and their behavior, intelligence, ability, values, and morals. If the idea is that some groups of people are essentially superior to others in cognitive ability and temperament, then it is easier to justify the unequal treatment of certain groups based on outward appearances. Another such problematic thinker was Paul Broca (1824\u20121880), after whom a region of the frontal lobe related to language use is named (Broca\u2019s area). Influenced by Morton, Broca likewise claimed that internal skull capacities could be linked with skin color and cognitive ability. He went on to justify the European colonization of other global territories by purporting it was noble for a biologically more \u201ccivilized\u201d population to improve the \u201chumanity\u201d of more \u201cbarbaric\u201d populations. Today, these theories of Morton, Broca, and others like them are known to have no scientific basis. If we could speak with them today, they would likely try to emphasize that their conclusions were based on empirical evidence and not <em>a priori<\/em> reasoning. However, we now can clearly see that their reasoning was biased and affected by prevailing societal views at the time.<\/p>\r\n\r\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d and the Beginnings of Physical Anthropology<\/strong><\/h3>\r\n<p class=\"import-Normal\">In the early 20th century, we saw a number of new figures coming into the science of human variation and shifting the theoretical focus within. Most notably, these included Ale\u0161 Hrdli\u010dka and Franz Boas.<\/p>\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"430\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image19-4.jpg\" alt=\"Historic photo of a middle-aged person in suit and bowtie.\" width=\"430\" height=\"558\" \/> Figure 14.8: Ale\u0161 Hrdli\u010dka (1869\u00ad\u20121943), a Czech anthropologist who founded the American Journal of Physical Anthropology. Credit: <a class=\"rId47\" href=\"https:\/\/siarchives.si.edu\/collections\/siris_sic_10822?back=%2Fcollections%2Fsearch%3Fquery%3Dczech%26online%3Dtrue%26page%3D1%26perpage%3D10%26sort%3Drelevancy%26view%3Dlist#\">(Ales Hrdlicka) SIA2009-4246<\/a> (1903) by an unknown photographer <a class=\"rId48\" href=\"https:\/\/www.si.edu\/termsofuse\">is used for educational and non-commercial purposes as outlined by the Smithsonian.<\/a>. [<a class=\"rId49\" href=\"https:\/\/www.si.edu\/\">Smithsonian Institution<\/a> Archives, Record Unit 9521, Box 1, T. Dale Stewart Oral History Interview; and Record Unit 9528, Box 1, Henry B. Collins Oral History Interview.][\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ale\u0161 Hrdli\u010dka (1869\u00ad\u20121943) was a Czech anthropologist who moved to the United States. In 1903, he established the physical anthropology section of the National Museum of Natural History (Figure 14.8). In 1918, he founded the <em>American Journal of Physical Anthropology<\/em>, which remains one of the foremost scientific journals disseminating bioanthropological research. As part of his work and the scope of the journal, he differentiated \u201c[pb_glossary id=\"2101\"]<strong>physical anthropology<\/strong>[\/pb_glossary]\u201d from other kinds of anthropology: he wrote that physical anthropology is \u201cthe study of racial anatomy, physiology, and pathology\u201d and \u201cthe study of man\u2019s variation\u201d (Hrdli\u010dka 1918). In some ways, although the scope and technological capabilities of biological anthropologists have changed significantly, Hrdli\u010dka established an area of inquiry that has continued and prospered for over a hundred years.<\/p>\r\n<p class=\"import-Normal\">Franz Boas (1858\u20121942) was a German American anthropologist who established the four-field anthropology system in the United States and founded the American Anthropological Association in 1902. He argued that the scientific method should be used in the study of human cultures and the comparative method for looking at human biology worldwide. One of Boas\u2019s significant contributions to biological anthropology was the study of skull dimensions with respect to race. After a long-term research project, he demonstrated how cranial form was highly dependent on cultural and environmental factors and that human behaviors were influenced primarily not by genes but by social learning. He wrote in one essay for the journal <em>Science<\/em>: \u201cWhile individuals differ, biological differences between races are small. There is no reason to believe that one race is by nature so much more intelligent, endowed with great willpower, or emotionally more stable than another, that the difference would materially influence its culture\u201d (Boas 1931:6). This conclusion directly contrasted with the theories of the past that relied on biological determinism. Biological anthropologists today have found evidence that corroborates Boas\u2019s explanations: societies do not exist on a hierarchy or gradation of \u201ccivilizedness\u201d but instead are shaped by the world around them, their demographic histories, and the interactions they have with other groups.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"358\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image2-7.png\" alt=\"Black-and-white sketch of tree labeled \u201cEugenics.\u201d \" width=\"358\" height=\"275\" \/> Figure 14.9: Logo of the Second International Exhibition of Eugenics, held in 1921. The text of the logo states: \"Eugenics is the self-direction of human evolution. Like a tree, eugenics draws its materials from many sources and organizes them into an harmonious entity.\" Credit: <a class=\"rId51\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Eugenics_congress_logo.png\">Eugenics congress logo<\/a> scanned from <a class=\"rId52\" href=\"https:\/\/en.wikipedia.org\/wiki\/Harry_H._Laughlin\">Harry H. Laughlin<\/a>, The Second International Exhibition of Eugenics held September 22 to October 22, 1921, is in the <a class=\"rId53\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The first half of the 1900s still involved some research that was essentialist and focused on proving racial determinism. Anthropologists like Francis Galton (1822\u20121911) and Earnest A. Hooton (1887\u20121954) created the field of <strong>[pb_glossary id=\"2730\"]eugenics[\/pb_glossary]<\/strong> as an attempt to formalize the social scientific study of \u201cfitness\u201d and \u201csuperiority\u201d among members of 19th-century Europe. As a way of \u201cdealing with\u201d criminals, diseased individuals, and \u201cuncivilized\u201d people, eugenicists recommended prohibiting parts of the population from being married or sterilizing these members of society so they could no longer procreate (Figure 14.9). They instead encouraged \u201creproduction in individual families with sound physiques, good mental endowments, and demonstrable social and economic capability\u201d (Hooton 1936). In the 1930s, Nazi Germany used this false idea of there being \u201cpure races\u201d to highly destructive effect. The need to be protected against admixture from \u201cunfit\u201d groups was their justification for their blatant racism and purging of citizens that fell under their subjective criteria.<\/p>\r\n<p class=\"import-Normal\">It should be noted that eugenicist ideas were popularly discussed and debated in many non-European contexts, as in the U.S., China, and South Africa, too. The Immigration Restriction Act of 1924 was passed in the United States, with the explicit aim of reducing the country\u2019s \u201cburden\u201d of people considered inferior by restricting immigration of eastern European Jews, Italians, Africans, Arabs, and Asians. In the early 1900s, Chinese scientists and politicians showed great interest in eugenic ideologies, which came to dictate decisions in law-making, family life, and the medical field. Noted American anthropologist Ruth Benedict wrote extensively on Japanese culture and society during and after World War II. Her essentialist portrayals of Japanese people were heavily cited in popular discourse at the time. In 1950s South Africa, interracial marriages and sexual relations were banned by law; antimiscegenation became one of the huge focuses of apartheid resistance activists in later years. We still see the continuation of eugenics-based logic today around the world\u2014in exclusionary immigration laws, cases of incarcerated prison inmates being forcibly sterilized, and the persistence of intelligence testing as a form of measuring people\u2019s \u201cfitness\u201d in a society.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Shortly after World War II and the Nazi Holocaust, the full extent of essentialist, eugenicist thinking became clear. Social constructions of race, and the notion that one can predict psychological or behavioral traits based on external appearance, had become unpopular both within and outside the discipline. It was up to those in the field of physical anthropology at the time to separate physical anthropology from race concepts that supported unscientific and socially damaging agendas. This does not mean that there are no physiological or behavioral differences between different members of the human species. However, going forward, a number of physical anthropologists saw human biological variation as more complicated than simple typologies could describe.<\/p>\r\n\r\n<h3 class=\"import-Normal\"><strong>\u201cThe New Physical Anthropology\u201d<\/strong><\/h3>\r\n[caption id=\"\" align=\"alignright\" width=\"219\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image14-6.png\" alt=\"Black-and-white photo of a person with short hair in a white shirt and tie.\" width=\"219\" height=\"291\" \/> Figure 14.10: Theodosius Dobzhansky, an important scientist who formulated the 20th-century \u201cmodern synthesis\u201d reconciling Charles Darwin\u2019s theory of evolution and Gregor Mendel\u2019s ideas on heredity. Credit: <a class=\"rId55\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Dobzhansky_no_Brasil_em_1943.jpg\">Dobzhansky no Brasil em 1943<\/a> by unknown photographer via <a class=\"rId56\" href=\"https:\/\/www.flickr.com\/photos\/celycarmo\/\">Flickr user Cely Carmo<\/a> is in the <a class=\"rId57\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\">After 1950, focus steered away from the concept of \u201crace\u201d as a unit of variation and toward understanding why variation exists in [pb_glossary id=\"2109\"]<strong>population<\/strong><strong>s<\/strong>[\/pb_glossary] from an evolutionary perspective. This was outlined by those pioneering the \u201cnew physical anthropology,\u201d such as Sherwood Washburn, Theodosius Dobzhansky (Figure 14.10), and Julian Huxley, who borrowed this approach from contemporary population geneticists. Whether using genetic or phenotypic markers as the units of study, \u201cgroups\u201d or \u201cclusters\u201d of humans differentiated by these became defined as populations that differ in the frequency of some gene or genes. Anthropologists consider what \u201cmakes\u201d a population\u2014a group of individuals potentially capable of or actually interbreeding due to shared geographic proximity, language, ethnicity, culture, and\/or values. Put another way, a population is a local interbreeding group with reduced gene flow between themselves and other groups of humans. Members of the same population may be expected to share many genetic traits (and, as a result, many phenotypic traits that may or may not be visible outwardly).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"240\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image15-6.png\" alt=\"Black-and-white photo of smiling person in a suit and tie in front of a building.\" width=\"240\" height=\"300\" \/> Figure 14.11: Julian Huxley (1942). Credit: <a class=\"rId59\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Julian_Huxley_1-2.jpg\">Julian Huxley 1-2<\/a> by unknown photographer is in the <a class=\"rId60\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\">Thinking of humans in terms of populations was part of Julian Huxley\u2019s (1942) \u201cModern Synthesis\u201d\u2014so named because it helped to reconcile two fundamental principles about evolution that had not been made sense of together before (Figure 14.11). As discussed in Chapter 3, Gregor Mendel (1822\u20121884) was able to show that inheritance was mediated by discrete particles (or genes) and not blended in the offspring. However, it was difficult for some 19th-century scientists to accept this model of genetic inheritance at the time because much of biological variation appeared to be continuous and not particulate (take skin color or height as examples). In the 1930s, it was demonstrated that traits could be polygenic and that multiple alleles could be responsible for any one phenotypic trait, thus producing the continuous variation in traits such as eye color that we see today. Thus, Huxley\u2019s \u201cModern Synthesis\u201d outlines not only how human populations are capable of exchanging genes at the microevolutionary level but also how multiple alleles for one trait (polygenic exchanges) can cause gradual macroevolutionary changes.<\/p>\r\n\r\n<h2 class=\"import-Normal\">Human Variation in Biological Anthropology Today<\/h2>\r\n<h3 class=\"import-Normal\"><strong>Many Human Traits Are Nonconcordant<\/strong><\/h3>\r\n<p class=\"import-Normal\">In our studies of human (genetic) variation today, we understand most human traits to be nonconcordant (Figure 14.12). \u201c[pb_glossary id=\"2105\"]<strong>Nonconcordance<\/strong>[\/pb_glossary]\u201d is a term used to describe how biological traits vary independent of each other\u2014that is, they do not get inherited in a correlative manner with other genetically controlled traits. For example, if you knew an individual had genes that coded for tall height, you would not be able to predict if they are lighter-skinned or have red hair. This is different from earlier essentialist views of human variation: the idea that skin color could predict one\u2019s brain function or even \u201ctemperament\u201d and tendencies toward criminal behavior.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"594\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image17-2-1.jpg\" alt=\"World map with human silhouettes scattered across the continents.\" width=\"594\" height=\"304\" \/> Figure 14.12: Most human biological traits are non-concordant, meaning traits vary independently and each trait has its own pattern of distribution around the world. In this image, different colors and patterns represent trait varieties. For example, the color and pattern of the head may represent hair color (dark to light), but sharing dark hair with another person does not mean you will share other traits (e.g. ability to digest lactose or ABO blood type). Credit: Nonconcordance original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Katie Nelson is under a <a class=\"rId62\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n<h3 class=\"import-Normal\"><strong>Human Variation Is Clinal\/Continuous (Not Discrete)<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Frank B. Livingstone (1928\u20122005) wrote: \u201cThere are no races, only clines\u201d (1962: 279). A <strong>[pb_glossary id=\"1875\"]cline[\/pb_glossary]<\/strong> is a gradation in the frequency of an allele\/trait between populations living in different geographic regions. Human variation cannot be broken into discrete \u201craces,\u201d because most physical traits vary on a continuous or \u201cclinal\u201d basis. One obvious example of this is how human height does not only come in three values (\u201cshort,\u201d \u201cmedium,\u201d and \u201ctall\u201d) but instead varies across a spectrum of vertical heights achievable by humans all over the world. On the one hand, we can describe human height as exhibiting [pb_glossary id=\"2106\"]<strong>continuous <\/strong><strong>variation<\/strong>[\/pb_glossary], forming a continuous pattern, but height does not vary according to where people live across the globe and does not exhibit a clinal pattern. On the other hand, skin color variation between populations does show patterning that fits quite well on to how near or far they are from each other on a world map. This makes a trait like skin color clinally distributed worldwide. When large numbers of genetic loci for large numbers of samples were sampled from human populations distributed worldwide during the 1960s and 1970s, the view that certain facets of human diversity were clinally distributed was further supported by genetic data.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To study human traits that are clinally distributed, genetic tests must be performed to uncover the true frequencies of an allele or trait across a certain geographic space. One easily visible example of a clinal distribution seen worldwide is the patterning of human variation in skin color. Whether in southern Asia, sub-Saharan Africa, or Australia, dark brown skin is found. Paler skin tones are found in higher-latitude populations such as those who have lived in areas like Europe, Siberia, and Alaska for millennia. Skin color is easily observable as a phenotypic trait exhibiting continuous variation.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">A clinal distribution still derives from genetic inheritance; however, clines often correspond to some gradually changing environmental factor. Clinal patterns arise when selective pressures in one geographic area differ from those in another as well as when people procreate and pass on genes together with their most immediate neighbors. There are several mechanisms, selective and neutral, that can lead to the clinal distribution of an allele or a biological trait. <strong>[pb_glossary id=\"2040\"]Natural selection[\/pb_glossary]<\/strong> is the mechanism that produced a global cline of skin color, whereby darker skin color protects equatorial populations from high amounts of UV radiation; there is a transition of lessening pigmentation in individuals that reside further and further away from the tropics (Jablonski 2004; Jablonski and Chaplin 2000; see Figure 14.13). The ability and inability to digest lactose (milk sugar) among different world communities varies according to differential practices and histories of milk and dairy-product consumption (Gerbault et al. 2011; Ingram et al. 2009). Where malaria seems to be most prevalent as a disease stressor on human populations, a clinal gradient of increasing sickle cell anemia experience toward these regions has been studied extensively by genetic anthropologists (Luzzatto 2012). Sometimes, culturally defined mate selection based on some observable trait can lead to clinal variation between populations as well.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"676\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image22-6.png\" alt=\"A global map shaded representing skin colors. \" width=\"676\" height=\"370\" \/> Figure 14.13: A global map of skin colors shows that dark skin pigmentation is more common in areas that receive more UV radiation (near the equator and in high altitude areas). Light skin is more common at northern and southern latitudes. It is worth bearing in mind, though, that these do not tell the full story of how human skin pigmentation varies worldwide. Each region will contain populations that exhibit a range of skin tones. In this way, this map is not perfect as an illustration of skin-color distribution. Credit: Mercator style projection map showing human skin color according to Biasutti 1940.png by Dark Tichondrias at English Wikipedia, modified (cropped) by Tuvalkin, is under a CC BY-SA 4.0 License.[\/caption]\r\n<p class=\"import-Normal\">Two neutral microevolutionary processes that may produce a cline in a human allele or trait are <strong>[pb_glossary id=\"1997\"]gene flow[\/pb_glossary]<\/strong> and <strong>[pb_glossary id=\"2000\"]genetic drift[\/pb_glossary] <\/strong>(see Chapter 4). The ways in which neutral processes can produce clinal distributions is seen clearly when looking at clinal maps for different blood groups in the human ABO blood group system (Figure 14.14). For instance, scientists have identified an East-to-West cline in the distribution of the blood type <em>B<\/em> allele across Eurasia. The frequency of <em>B<\/em> allele carriers decreases gradually westward when we compare the blood groups of East and Southeast Asian populations with those in Europe. This shows how populations residing nearer to one another are more likely to interbreed and share genetic material (i.e., undergo gene flow). We also see 90%\u2012100% of native South American individuals, as well as between 70%\u201290% of Aboriginal Australian groups, carrying the <em>O<\/em> allele (Mourant, \u200b\u200bKope\u0107, and Domaniewska-Sobczak 1976). These high frequencies are likely due to random genetic drift and founder effects, in which population sizes were severely reduced by the earliest <em>O<\/em> allele-carrying individuals migrating into those areas. Over time, the <em>O<\/em> blood type has remained predominant.<\/p>\r\n<p class=\"import-Normal\"><img class=\"aligncenter\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image8.gif\" alt=\"World map showing varying frequencies of blood type A.\" width=\"516\" height=\"284\" \/><\/p>\r\n<p class=\"import-Normal\"><img class=\"aligncenter\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image5.gif\" alt=\"World map shows the highest frequencies of blood type B in parts of Asia.\" width=\"518\" height=\"283\" \/><\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"516\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image13.gif\" alt=\"World map shows the highest frequencies of blood type O.\" width=\"516\" height=\"284\" \/> Figure 14.14a\u2013c: a. Global distribution of blood type A. b. Global distribution of blood type B. c. Global distribution of blood type O. <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\" target=\"_blank\" rel=\"noopener\">A text description of this image is available<\/a>. Credit: a. <a class=\"rId69\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Map_of_blood_group_a.gif\">Map of blood group a<\/a> by <a class=\"rId70\" href=\"https:\/\/en.wikipedia.org\/wiki\/User:Muntuwandi\">Muntuwandi<\/a> at <a class=\"rId71\" href=\"https:\/\/en.wikipedia.org\/\">en.wikipedia<\/a> is under a <a class=\"rId72\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>. b. <a class=\"rId73\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Map_of_blood_group_b.gif\">Map of blood group b<\/a> by <a class=\"rId74\" href=\"https:\/\/en.wikipedia.org\/wiki\/User:Muntuwandi\">Muntuwandi<\/a> at <a class=\"rId75\" href=\"https:\/\/en.wikipedia.org\/\">en.wikipedia<\/a> is under a <a class=\"rId76\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>. c. <a class=\"rId77\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Map_of_blood_group_o.gif\">Map of blood group o<\/a> is based on diagrams from <a class=\"rId78\" href=\"https:\/\/anthro.palomar.edu\/vary\/vary_3.htm\">https:\/\/anthro.palomar.edu\/vary\/vary_3.htm<\/a>, reproduced from A. E. Mourant et al. (1976), and is under a <a class=\"rId79\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>.[\/caption]\r\n<h3 class=\"import-Normal\"><strong>Genetic Variation Is Greater Within Group than Between Groups<\/strong><\/h3>\r\n[caption id=\"\" align=\"alignleft\" width=\"295\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image27-2.jpg\" alt=\"Two medium-sized circles labeled Asian and European largely overlap. A larger circle labeled African surrounds both. \" width=\"295\" height=\"274\" \/> Figure 14.15: Circles represent human genetic variation. Most variants are shared among individuals on all continents. There are more variants in Africa, some of which are not found in Europe or Asia. Credit: Human Genetic Variation original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Katie Nelson is under a <a class=\"rId81\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\nOne problem with race-based classifications is they relied on an erroneous idea that individuals with particular characteristics would share more similar genes with each other within a particular \u201crace\u201d and share less with individuals of other \u201craces\u201d possessing different traits and genetic makeups. However, since around 50 years ago, scientific studies have shown that the majority of human genetic differences worldwide exist <em>within<\/em> groups (or \u201craces\u201d) individually rather than <em>between<\/em> groups. Indeed, most genetic variation we see occurs in Africa, and many variants are shared among individuals on all continents (Figure 14.15).\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">In 2002, a landmark article by Noah Rosenberg and colleagues explored worldwide human genetic variation using an even-greater genetic data set. They used 377 highly variable markers in the human genome and sampled from 1,056 individuals representative of 52 populations. The markers chosen for study were not ones that code for any expressed genes. Because these regions of the human genome were made of unexpressed genes, we may understand these markers as neutrally derived (as opposed to selectively derived) because they do not code for functional advantages or disadvantages. These neutral genetic markers likely reflect an intricate combination of regional founder effects and population histories. Analyses of these neutral markers allowed scientists to identify that 93%\u201295% of global genetic differences, referred to as <strong>[pb_glossary id=\"2113\"]variance[\/pb_glossary]<\/strong>, can be accounted for by within-population differences, while only a small proportion of genetic variance (3%\u20125%) can be attributed to differences among major groups (Rosenberg et al. 2002). This research supports the theory that distinct biological races do not exist, even though misguided concepts of race may still have real social and political consequences.<\/p>\r\n\r\n<h3 class=\"import-Normal\"><strong>Biological Data Fit Isolation-By-Distance and Out-of-Africa Models<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">One further note is that the world\u2019s population may be genetically divided into \u201cgroups,\u201d \u201csubsets,\u201d \u201cclumps,\u201d or \u201cclusters\u201d that reflect some degree of genetic similarity. These identifiable clusters reflect genetic or geographic distances\u2014either with gene flow facilitated by proximity between populations or impeded by obstacles like oceans or environmentally challenging habitats (Rosenberg et al. 2005). Sometimes, inferred clusters using multiple genetic loci are interpreted by nongeneticists literally as \u201cancestral populations.\u201d However, it would be wrong to assume from these genetic results that highly differentiated and \u201cpure\u201d ancestral groups ever existed. These groupings reflect differences that have arisen over time due to clinal patterning, genetic drift, and\/or restricted or unrestricted gene flow (Weiss and Long 2009). The clusters identified by scientists are arbitrary and the parameters used to split up the global population into groups is subjective and dependent on the particular questions or distinctions being brought into focus (Relethford 2009).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"341\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image6-7.png\" alt=\"Map of the continent of Africa with the lower two-thirds shaded.\" width=\"341\" height=\"341\" \/> Figure 14.16: Sub-Saharan Africa (shaded dark\/green). Credit: <a class=\"rId83\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Sub-Saharan-Africa.png\">Sub-Saharan Africa<\/a> by <a class=\"rId84\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Ezeu\">Ezeu<\/a> has been designated to the <a class=\"rId85\" href=\"https:\/\/creativecommons.org\/share-your-work\/public-domain\/cc0\/\">public domain (CC0)<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Additionally, research on worldwide genetic variation has shown that human variation decreases with increasing distance from sub-Saharan Africa, where there is evidence for this vast region being the geographical origin of anatomically modern humans (Liu et al. 2006; Prugnolle, Manica, and Balloux 2005; see Figures 14.16 and 14.17). Genetic differentiation decreases in human groups the further you sample data from relative to sub-Saharan Africa because of serial founder effects (Relethford 2004). Over the course of human colonization of the rest of the world outside Africa, populations broke away in expanding waves across continents into western Asia, then Europe and eastern Asia, followed by Oceania and the Americas. As a result, founder events occurred whereby genetic variation was lost, as the colonization of each new geographical region involved a smaller number of individuals moving from the original larger population to establish a new one (Relethford 2004). The most genetic variation is found across populations residing in different parts of sub-Saharan Africa, while other current populations in places like northern Europe and the southern tip of South America exhibit some of the least genetic differentiation relative to all global populations (Campbell and Tishkoff 2008).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"469\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image3-6.png\" alt=\"Two scatterplots.\" width=\"469\" height=\"516\" \/> Figure 14.17: Comparison of the genetic distance and geographical distance between populations. In the top graph, the pattern reveals that genetic variation conforms to an Out-of-Africa model, as those populations further away from Addis Ababa in Ethiopia share a smaller number of alleles; in the bottom graph, we see the populations follow an isolation-by-distance model, as pairs of populations further apart geographically seem to have greater genetic distance (Kanitz et al. 2018). Credit: <a class=\"rId87\" href=\"https:\/\/journals.plos.org\/plosone\/article?id=10.1371\/journal.pone.0192460\">Complex genetic patterns (figure 1)<\/a> by Kanitz et al. (2018) is under a <a class=\"rId88\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY 4.0 License<\/a>.[\/caption]\r\n\r\n<\/div>\r\n<div class=\"__UNKNOWN__\">\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"377\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image1-9.png\" alt=\"Two large circles connected by a small area.\" width=\"377\" height=\"309\" \/> Figure 14.18: The founder effect is a change in a small population\u2019s gene pool due to a limited number of individuals breaking away from a parent population. Credit: <a class=\"rId90\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Bottleneck_effect.jpg\">Bottleneck effect<\/a> by <a class=\"rId91\" href=\"https:\/\/wikieducator.org\/User:Tsaneda\">Tsaneda<\/a> is under a <a class=\"rId92\" href=\"https:\/\/creativecommons.org\/licenses\/by\/3.0\/legalcode\">CC BY 3.0 License<\/a>.[\/caption]\r\n\r\nBesides fitting nicely into the <strong>[pb_glossary id=\"2116\"]Out-of-Africa model[\/pb_glossary]<\/strong>, worldwide human genetic variation conforms to an <strong>[pb_glossary id=\"2129\"]isolation-by-distance model[\/pb_glossary]<\/strong>, which predicts that genetic similarity between groups will decrease exponentially as the geographic distance between them increases (Kanitz et al. 2018). This is because of the greater and greater restrictions to gene flow presented by geographic distance, as well as cultural and linguistic differences that occur as a result of certain degrees of isolation. Since genetic data conform to isolation-by-distance and Out-of-Africa models, these findings support the abolishment of \u201crace\u201d groupings. This research demonstrates that human variation is continuous and cannot be differentiated into geographically discrete categories. There are no \u201cinherent\u201d or \u201cinnate\u201d differences between human groups; instead, variation derives from some degree of natural selection, as well as neutral processes like [pb_glossary id=\"2731\"]<strong>population bottle-necking<\/strong>[\/pb_glossary] (Figure 14.18), random [pb_glossary id=\"1474\"]<strong>mutations<\/strong>[\/pb_glossary] in the DNA, genetic drift, and gene flow through between-mate interbreeding.\r\n<h3 class=\"import-Normal\"><strong>Humans Have Higher Homogeneity Compared to Many Other Species<\/strong><\/h3>\r\n<p class=\"import-Normal\">An important fact to bear in mind is that humans are 99.9% identical to one another. This means that the apportionments of human variation discussed above only concern that tiny 0.1% of difference that exists between all humans globally. Compared to other mammalian species, including the other great apes, human variation is remarkably lower. This may be surprising given that the worldwide human population has already exceeded seven billion, and, at least on the surface level, we appear to be quite phenotypically diverse. Molecular approaches to human and primate genetics tells us that external differences are merely superficial. For a proper appreciation of human variation, we have to look at our closest relatives in the primate order and mammalian class. Compared to chimpanzees, bonobos, gorillas and other primates, humans have remarkably low average genome-wide <strong>[pb_glossary id=\"2118\"]heterogeneity[\/pb_glossary]<\/strong> (Osada 2005).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">When we look at chimpanzee genetic variation, it is fascinating that western, central, eastern, and Cameroonian chimpanzee groups have substantially more genetic variation between them than large global samples of human DNA (Bowden et al. 2012; Figure 14.19). This is surprising given that all of these chimpanzee groups live relatively near one another in Africa, while measurements of human genetic variation have been conducted using samples from entirely different continents. First, geneticists suppose that this could reflect differential experiences of the founder effect between humans and chimpanzees. As it has been argued that all non-African human populations descended from a small number of anatomically modern humans who left Africa, it would be expected that all groups descended from that smaller ancestral group would be similar genetically. Second, our species is really young, given that we have only existed on the planet for around 150,000 to 300,000 years. This gave humans little time for random genetic mutations to occur as genes get passed down through genetic interbreeding and meiosis. Chimpanzees, however, have inhabited different [pb_glossary id=\"2119\"]<strong>ecological niches<\/strong>[\/pb_glossary], and less interbreeding has occurred between the four chimpanzee groups over the past six to eight million years compared to the amount of gene flow that occurred between worldwide human populations (Bowden et al. 2012).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"648\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image16-7.png\" alt=\"Map of Africa showing the ranges of chimpanzees from west to east.\" width=\"648\" height=\"339\" \/> Figure 14.19: Distribution of the genus Pan, including bonobos and the four subspecies of chimpanzee, across western and central Africa (Clee et al. 2015). <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\" target=\"_blank\" rel=\"noopener\">A text description of this image is available<\/a>. Credit: <a class=\"rId94\" href=\"https:\/\/bmcecolevol.biomedcentral.com\/articles\/10.1186\/s12862-014-0275-z\">Chimpanzee subspecies ranges (Figure 1)<\/a> by Clee et al. 2015 is under a <a class=\"rId95\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Recent advances have now enabled the attainment of genetic samples from the larger family of great apes and the evaluation of genetic variation among bonobos, orangutans, and gorillas alongside that of chimpanzees and humans (Prado-Martinez et al. 2013). Collecting such data and analyzing primate genetic variation has been important not only to elucidate how different ecological, demographic, and climatic factors have shaped our evolution but also to inform upon conservation efforts and medical research. Genes that may code for genetic susceptibilities to tropical diseases that affect multiple primates can be studied through genome-wide methods. Species differences in the genomes associated with speech, behavior, and cognition could tell us more about how human individuals may be affected by genetically derived neurological or speech-related disorders and conditions (Prado-Martinez et al. 2013; Staes et al. 2017). In 2018, a great ape genomic study also reported genetic differences between chimpanzees and humans related to brain cell divisions (Kronenberg et al. 2018). From these results, it may be inferred that cognitive or behavioral variation between humans and the great apes might relate to an increased number of cortical neurons being formed during human brain development (Kronenberg et al. 2018). Comparative studies of human and nonhuman great ape genetic variation highlight the complex interactions of population histories, environmental changes, and natural selection between and within species. When viewed in the context of overall great ape variation, we may reconsider how variable the human species is relatively and how unjustified previous \u201crace\u201d concepts really were.<\/p>\r\n\r\n<h3 class=\"import-Normal\"><strong>Phenotypic Traits That Reflect Neutral Evolution<\/strong><\/h3>\r\n<p class=\"import-Normal\">Depending on the trait being observed, different patterns of phenotypic variation may be found within and among groups worldwide. In this subsection, some phenotypic traits that reflect the aforementioned patterns of genetic variation will be discussed.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"301\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image18-4.jpg\" alt=\"Illustration of one anthropologist studying teeth, and another looking into a microscope.\" width=\"301\" height=\"301\" \/> Figure 14.20: Contemporary anthropologists who use many types of skeletal markers have demonstrated that a majority of cranial variation occurs within populations rather than between populations and that there is a decrease in variation with distance from Africa. Credit: <a class=\"rId97\" href=\"https:\/\/img1.wsimg.com\/isteam\/ip\/0f6c1c17-41ea-4caf-b839-73c676d69f01\/DentalHeartNecklace.jpg\/:\/rs=w:1280,h:1280\">Dental Anthropologist Heart Necklace<\/a> by <a class=\"rId98\" href=\"https:\/\/anthroillustrated.com\/\">Anthro Illustrated<\/a> is under a <a class=\"rId99\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Looking beyond genetic variation briefly, recent studies have revisited biological anthropology\u2019s earlier themes of externally observable traits, such as skull shape. In the last 20 or so years, anthropologists have evaluated the level to which human cranial shape variation reflects the results from genetic markers, such as those used previously to fit against Out-of-Africa models (Relethford 2004) or those used in the apportionment of human variation between and within groups (Lewontin 1972; Rosenberg et al. 2002). Using larger sample sizes of cranial data collected from thousands of skulls worldwide and a long list of cranial measurements, studies demonstrate a similar decrease in variation with distance from Africa and show that a majority of cranial variation occurs within populations rather than between populations (Betti et al. 2009; Betti et al. 2010; Manica et al. 2007; Relethford 2001; von Cramon-Taubadel and Lycett 2008; see Figure 14.20). The greatest cranial variation is found among skulls of sub-Saharan African origin, while the least variation is found among populations inhabiting places like Tierra del Fuego at the southern tip of Argentina and Chile. While ancient and historical thinkers previously thought \u201crace\u201d categories could reasonably be determined based on skull dimensions, modern-day analyses using more informative sets of cranial traits simply show that migrations out of Africa and the relative distances between populations can explain a majority of worldwide cranial variation (Betti et al. 2009).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"250\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image21-6.png\" alt=\"Sketch of bone with bony loops at the top and coil at the bottom.\" width=\"250\" height=\"208\" \/> Figure 14.21: Diagram of the bony labyrinth in the inner ear. Credit: <a class=\"rId101\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Bony_labyrinth.png\">Bony labyrinth<\/a> by <a class=\"rId102\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Selket\">Selket<\/a> has been designated to the <a class=\"rId103\" href=\"https:\/\/creativecommons.org\/share-your-work\/public-domain\/cc0\/\">public domain (CC0)<\/a>.[\/caption]\r\n<p class=\"import-Normal\">This same patterning in phenotypic variation has even been found in studies examining shape variation of the pelvis (Betti et al. 2013; Betti et al. 2014), the teeth (Rathmann et al. 2017), and the human <strong>[pb_glossary id=\"2122\"]bony labyrinth[\/pb_glossary]<\/strong> of the ear (Ponce de Le\u00f3n et al. 2018;Figure 14.21). The skeletal morphology of these bones still varies worldwide, but a greater proportion of that variation can still be attributed to the ways in which human populations migrated across the world and exchanged genes with those closer to them rather than those further away. Human skeletal variation in these parts of the body is continuous and nondiscrete. Given the important functions of the cranium and these other skeletal parts, we may infer that the genes that underpin their development have been relatively conserved by neutral evolutionary processes such as genetic drift and gene flow. It is also important to note that while some traits such as height, weight, cranial dimensions, and body composition are determined, in part, by genes, the underlying developmental processes behind these traits are underpinned by complex polygenic mechanisms that have led to the continuous spectrum of variation in such variables among modern-day human populations.<\/p>\r\n\r\n<h3 class=\"import-Normal\"><strong>Phenotypic Traits That Reflect Natural Selection<\/strong><\/h3>\r\n<p class=\"import-Normal\">Even though 99.9% of our DNA is the same across all humans worldwide, and many traits reflect neutral processes, there are parts of that remaining 0.1% of the human genome that code for individual and regional differences. Similarly to craniometric analyses that have been conducted in recent decades, human variation in skin color has also been reassessed using new methods and in light of greater knowledge of biological evolution.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">New technologies allow scientists to use color photometry to sample and quantify the visible wavelength of skin color, in a way 19th- and 20th-century readers could not. In one report, it was found that 87.9% of global skin color variation can be attributed to genetic differences <em>between<\/em> groups, 3.2% to those among local populations within regions, and 8.9% <em>within<\/em> local populations (Relethford 2002). This apportionment differs significantly and is the reverse situation found in the distribution of genetic differences we see when we examine genetic markers such as blood type\u2013related alleles. However, this pattern of human skin color worldwide is not surprising, given that we now understand that past selection has occurred for darker skin near the equator and lighter skin at higher latitudes (Jablonski 2004; Jablonski and Chaplin 2000). While most genetic variation reflects neutral variation due to population migrations, geographic isolation, and restricted gene flow dynamics, some human genetic\/phenotypic variation is best explained as local adaptation to environmental conditions (i.e., selection). Given that skin color variation is atypical compared to other genetic markers and biological traits, this, in fact, goes against earlier \u201crace\u201d typologies. This is because recent studies ironically show how so much of genetic variation relates to neutral processes, while skin color does not. It follows that skin color <em>cannot<\/em> be viewed as useful in making inferences about other human traits.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"580\"]<img class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image23-3.jpg\" alt=\"Person standing at podium in front of a screen with arms partly raised.\" width=\"580\" height=\"384\" \/> Figure 14.22: Genomicists and biological anthropologists have dedicated efforts to improving quantitative methods of measuring hair and skin variation over the last twenty years. Dr. Nina Jablonski is one such biological anthropologist specializing in the evolution and variation of human skin pigmentation. Credit: <a class=\"rId105\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Nina_Jablonski_2016_The_Skin_of_Homo_sapiens_01_%28cropped%29.jpg\">Nina Jablonski 2016 The Skin of Homo sapiens 01 (cropped)<\/a> by <a class=\"rId106\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Ptolusque\">Ptolusque<\/a> is under a <a class=\"rId107\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\">CC BY-SA 4.0 license<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">It is also true that some populations have not been studied extensively in skin pigmentation genetics (e.g., African, Austronesian, Melanesian, Southeast Asian, Indigenous American, and Pacific Islander populations, according to Lasisi and Shriver 2018). Earlier dispersals of these populations, and their local genetic varition, will have contributed to worldwide genetic variation, inclusive of skin pigmentation variation. Gene loci we did not previously appreciate as being linked to pigmentation are now being recognized thanks to better tools, more diverse genetic samples, and more accessible datasets (Quillen et al. 2018). Biological anthropologists look forward to further discoveries elucidating the different selective pressures and population dynamics that influence skin pigmentation evolution.<\/p>\r\n\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Social Implications<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To finish this chapter, we will consider the social, economic, political, and biological implications of poor understandings of race and the deliberate perpetuation of social and medical racism.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The Black Lives Matter movement (BLM) of 2013 began with the work of racial justice activists and community organizers Alicia Garza, Opal Tometi, and Patrissa Cullors. First incited by the murder of Trayvon Martin, a 17-year-old African American, and the acquittal of the man who shot him, BLM went on to protest against the deaths of numerous Black individuals, most of whom were killed by police officers (for example, Ahmaud Arbery was killed in February of 2020 by two white non-police officers). Some key characteristics of BLM from the start were its decentralized grassroots structure, the role of university students and social media in spreading awareness of the movement, and its embrace of other movements (e.g., climate justice, ending police brutality, feminist campaigns, queer activism, immigration reform, etc.). When George Floyd was murdered by a white police officer on May 25, 2020, the BLM gained new momentum, across 2,000-plus cities in the United States, and among many protesting against historic racism and police brutality in other contexts around the globe. Many in the biological anthropology community have responded to these events with a great dedication to working against systemic racism in society and institutions (American Association of Biological Anthropologists 2020).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">BLM continues to be an important movement, as is evidenced in the degree of community organizing, mutual aid efforts, calls for political reform, progress toward curriculum reform and equality, inclusion and diversity (EDI) work in businesses and universities, the removal of monuments honoring historical figures associated with slavery and racism, and many other important actions. Garza (2016) writes: \u201cThe reality is that race in the United States operates on a spectrum from black to white \u2026 the closer you are to white on that spectrum, the better off you are.\u201d Tometi (2016) has stated: \u201cWe need [a human rights movement that challenges systemic racism] because the global reality is that Black people are subject to all sorts of disparities in most of our challenging issues of our day. I think about climate change, and how six of the ten worst impacted nations by climate change are actually on the continent of Africa.\u201d In the words of Cullors (2016), \u201cBlack Lives Matter is our call to action. It is a tool to reimagine a world where Black people are free to exist, free to live. It is a tool for our allies to show up differently for us.\u201d We gather from their words the importance of learning from the egregious role that anthropologists have played in the past, recognizing the legacies of \u201cscientific\u201d justifications for eugenics and racism in our society today, and proactively working toward environmental and social equity.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Another major industry that engages in the quantification and interpretation of human variation is medical and clinical work (National Research Council [U.S.] Committee on Human Genome Diversity 1997). Large-scale genomic studies sampling from human populations distributed worldwide have produced detailed knowledge on variation in disease resistance or susceptibility between and within populations. Let\u2019s think about drug companies who develop medicines for Black patients particularly. The predispositions to particular diseases are higher among people of African descent than some pharmaceutical businesses have taken into account. Through targeted sampling of various world groups, clinical geneticists may also identify genetic risk factors of certain common disorders such as chronic heart disease, asthma, diabetes, autoimmune diseases, and behavioral disorders. Having an understanding of population-specific biology is crucial in the development of therapies, medicines, and vaccinations, as not all treatments may be suitable for every human, depending on their genotype. During diagnosis and treatment, it is important to have an evolutionary perspective on gene-environment relationships in patients. Typological concepts of \u201crace\u201d are not useful, given that most racial groups (whether self-identified or not) popularly recognized lack homogeneity and are, in fact, variable. <strong>[pb_glossary id=\"2123\"]Cystic fibrosis[\/pb_glossary]<\/strong>, for instance, occurs in all world populations but can often be underdiagnosed in populations with African ancestry because it is thought of as a \u201cwhite\u201d disease (Yudell et al. 2016).<\/p>\r\n<p class=\"import-Normal\">Sociologists, law scholars, and professors of race studies have written extensively on how genetic\/technological\/medical revolutions impact people of color. In her book, <em>Fatal Invention: How Science, Politics, and Big Business Re-create Race in the Twenty-First Century <\/em>(2013), Professor Dorothy E. Roberts writes about how technological advances have been used in resuscitating race as a biological category for dividing humans in essentialist ways (Figure 14.23). She notes how members of law enforcement have engaged in racial profiling, sometimes with the use of machine-learning and facial-recognition technologies. Ancestry-testing services also purport to tell us \u201cwhat\u201d we are and to insist that this information is \u201cwritten\u201d in our genes. Such advertising campaigns obscure the nuances of genetic variation with the primary motive of tapping into people\u2019s desire to \u201cknow themselves\u201d and driving up profits for their businesses. Commercial genetic testing reinforces the idea that genes map neatly onto race, all while generating massive stores of data in DNA databases. In Roberts\u2019s view, the myth of the biological concept of race being perpetuated in these ways undermines a just society and reproduces racial inequalities.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"593\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image12-6.png\" alt=\"Book cover with two DNA strands and next to the smiling portrait of the author.\" width=\"593\" height=\"305\" \/> Figure 14.23: Professor Dorothy E. Roberts is a sociologist, legal scholar, and expert on the relationships among technology, medicine, bioethics, policymaking, race, and racism. Credit: <a class=\"rId109\" href=\"https:\/\/kpfa.org\/episode\/talkies-august-23-2016\/\">Dorothy Roberts author of Fatal Invention<\/a> by <a class=\"rId110\" href=\"https:\/\/kpfa.org\/\">https:\/\/kpfa.org\/<\/a> is copyrighted and used with permission.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The COVID-19 pandemic has had a significant impact on the world\u2019s population, particularly people living in the economic Global South and many Black, Indigenous and communities of color residing in the Global North. We have witnessed disproportionately high numbers of COVID-related deaths and infection cases among marginalized groups. Many immigrants and ethnic minorities in various societies have also experienced scapegoating and blame directed at them for being the source of COVID-19 spread.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To inform us on how to interpret this current worldwide pandemic, historians and anthropologists are looking back at the lessons learned from past instances of racist medicine (discriminatory practices based on broader social discrimination) and medical racism (application of discriminatory practices justified on medical grounds). Historically, who could become doctors and medical professionals was often racialized, gendered, and class specific. This made it difficult for many to overcome prejudices against women, Black people, Indigenous individuals, or other people of color from becoming doctors and clinical researchers in places such as South Africa and the United States. This, in turn, affects the sorts of information we know about health levels and health outcomes among these very groups. In the past decade, long-overdue attention is finally being paid to how race affects biological outcomes. For instance, researchers have focused on the negative legacies of racial discrimination and racism-induced stress on hormone (im)balances, mental health disorders, cardiovascular disease prevalence, and other health outcomes (Kuzawa and Sweet 2009; Shonkoff, Slopen, and WIlliams 2021; Williams 2018). The technology and standards of protocol in medical testing have been scrutinized (for more on how pulse oximeters were not designed with nonwhite patients in mind, for example, see Sjoding et al. 2020). Scholars of race and medicine have also written on how illness and disease spread have often been used to perpetuate societal prejudices. This manifests as xenophobic tendencies at a societal level, such as the blaming of \u201coutgroups\u201d and increased \u201cin-group\u201d protectiveness. Overreliance on the idea that people are \u201cinherently\u201d disease carriers due to genetic or biological reasons leads to improper accounting for socioeconomic or infrastructural issues that lead to differential disease prevalence amongst minority communities. (For more on race and COVID, see Tsai 2021 as well as this textbook\u2019s Chapter 16: Contemporary Topics: Human Biology and Health.)<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">It is important to remember that while it is possible to look for clues about one\u2019s ancestry or geographic origin based on skull morphology, again, the amount of distinctiveness in any given sample makes it impossible to distinguish whether a cranium belongs to one group (Relethford 2009). Individuals can vary in their skeletal dimensions by continental origin, country origin, regional origin, sex, age, environmental factors, and the time period in which they lived, making it difficult to assign individuals to particular categories in a completely meaningful way (Ousley, Jantz, and Freid 2009). When forensic reports and scientific journal articles give an estimation of ancestry, it is crucial to keep in mind that responsible assignments of ancestry will be done through robust statistical testing and stated as a probability estimate. Today, we also live in a more globalized world where a skeletal individual may have been born originally to parents of two separate traditional racial categories. In contexts of great heterogeneity within populations, this definitely adds difficulty to the work of forensic scientists and anthropologists preparing results for the courtroom (genetic testing may be comparatively more helpful in such situations).<\/p>\r\n\r\n<\/div>\r\n<div class=\"textbox\">\r\n<h2 class=\"import-Normal\">Dig Deeper: Measuring F<sub>ST<\/sub><\/h2>\r\n<p class=\"import-Normal\">Richard Lewontin (1929\u2012) is a biologist and evolutionary geneticist who authored an article evaluating where the total genetic variation in humans lies. Titled \u201cThe Apportionment of Human Diversity\u201d (Lewontin 1972), the article addressed the following question: On average, how genetically similar are two randomly chosen people from the same group when compared to two randomly chosen people from different groups?<\/p>\r\n<p class=\"import-Normal\">Lewontin studied this problem by using genetic data. He obtained data for a large number of different human populations worldwide using 17 genetic markers (including alleles that code for various important enzymes and proteins, such as blood-group proteins). The statistical analysis he ran used a measure of human genetic differences in and among populations known as the fixation index (F<sub>ST<\/sub>).<\/p>\r\n<p class=\"import-Normal\">Technically, F<sub>ST<\/sub> can be defined as the proportion of total genetic variance within a <em>subpopulation<\/em> relative to the total genetic variance from an <em>entire population<\/em>. Therefore, F<sub>ST<\/sub> values range from 0 to 1 (or, sometimes you will see this stated as a percentage between 0% and 100%). The closer the F<sub>ST<\/sub> value of a population (e.g., the world\u2019s population) approaches 1, the higher the degree of genetic differentiation among subpopulations relative to the overall population (see Figure 14.24 for a detailed illustration).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"561\"]<img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image4-5.jpg\" alt=\"Three cases each illustrate two populations with a mix of two types of alleles.\" width=\"561\" height=\"473\" \/> Figure 14.24: This diagram shows a range of different case studies with which we may understand how FST is calculated in different populations. In Case 1, the gene pools of Populations 1 and 2 are 100% different from each other but possess 0% variation within themselves, so FST has a value of 1. When there is no genetic variation at all between two populations and 100% variation within them, as in Case 2, we see that FST is calculated as 0. When we look at Case 3, where variation between and within are some values between 0% and 100%, we will get a decimal figure for FST dependent upon how much variation there is between and within populations. It is through such comparisons of population genetic data that we may quantify the relative similarities or differences between and within populations, and we may thus speak to the nonexistence of \u201cracial groups\u201d that divide up our species into broad continental or racial categories. Credit: F<sub>ST<\/sub> original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Katie Nelson is under a <a class=\"rId112\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\n&nbsp;\r\n\r\nIn his article, Lewontin (1972) identified that most of human genetic differences (85.4%) were found within local subpopulations (e.g., the Germans or Easter Islanders), whereas 8.3% were found between populations within continental human groups, and 6.3% were attributable to traditional \u201crace\u201d groups (e.g., \u201cCaucasian\u201d or \u201cAmerind\u201d). These findings have been important for scientifically rejecting the existence of biological races (Long and Kittles 2003).\r\n\r\n<\/div>\r\n<div class=\"__UNKNOWN__\">\r\n<h2 class=\"import-Normal\">Talking About Human Biological Variation Going Forward<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To conclude, utilizing the term <em>races<\/em> to describe human biological variation is not accurate or productive. Using a select few hundred genetic loci, or perhaps a number of phenotypic traits, it may be possible to assign individuals to a geographic ancestry, but what constitutes a bounded genetic or geographical grouping is both arbitrary and potentially harmful owing to ethical and historical reasons. The discipline of biological anthropology has moved past typological frameworks that shoehorn continuously variable human populations into discrete and socially constructed subsets. Improvements in the number of markers, the genetic technologies used to study variation, and the number of worldwide populations sampled have led to more nuanced understandings of human variation. It is of utmost importance that scientists make the following points clear to the public:<\/p>\r\n\r\n<ul>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt\">Today, we refer to different local human groups as \u201cpopulations.\u201d What constitutes a population should be carefully defined in scientific reports based on some geographical, linguistic, or cultural criteria and some degree of relativity to other closely or distantly related human groups.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt\">Humans have significantly less genetic variation than other primates and mammals, and all human beings on Earth share 99.9% of their overall DNA. Some of the remaining 0.1% of human variation varies on a clinal or continuous basis, such as can be seen when looking at ABO blood-type [pb_glossary id=\"2125\"]<strong>polymorphisms<\/strong>[\/pb_glossary] worldwide.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt\">Many biological characteristics in humans are actually determined nonconcordantly and\/or polygenically. Therefore, superiority or inferiority in human behavior or body form cannot justifiably be linked to fixed and innate differences between groups.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt\">Genetic distances are correlated with geographic distances among the global human population. This is especially apparent when we consider that genetic variation is highest in sub-Saharan Africa, and average genetic heterogeneity decreases in populations further away from the African continent in accordance with the migratory history of anatomically modern <em>Homo sapiens<\/em>.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt\">The effects of gene flow, genetic drift, and population bottlenecking are reflected in some phenotypic traits, such as cranial shape.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt\">We recognize other traits, like skin color and lactase persistence, to be the products of many millennia of natural selective pressures influencing human biology from the external environment.<\/li>\r\n<\/ul>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Taken together, genetic analyses of human variation do not support 20th-century (or even-earlier) concepts of race. In discussions about human variation, these genomic results help clarify how biological variation is distributed across the human population today. Taking care to think about and debate the nature of human variation is important, because although the effects and events that produced genetic differences among groups occurred in the ancient past, sociocultural concepts about race and ethnicity continue to have real social, economic, and political consequences.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Beyond talking about variation in the university setting, it is important that teachers, researchers, and students of anthropology recognize and assume the responsibility of influencing public perspectives of human variation. Race-based classification systems were developed during the colonial era, the transatlantic trafficking of kidnapped Africans and the so-called \u201cScientific Revolution\u201d by the first \u201canthropologists\u201d and scholars of humankind\u2019s variation. Unfortunately, some of their early ideas have persisted and evolved into present-day lived realities. Some of today\u2019s politicians and socioeconomic bodies have racially charged agendas that promote racism or certain kinds of economic or racial inequalities. As anthropologists, we must acknowledge that while human \u201craces\u201d are not a biological reality, their status as a (misguided) social construction does have real consequences for many people (Antrosio 2011).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">In other words, while \u201crace\u201d is a sociocultural invention, the treatment different individuals receive due to their perceived \u201crace\u201d can have significant financial, emotional, sociopolitical, and physiological costs. However\u2014and importantly assuming a \u201ccolor-blind\u201d position when it comes to the topics of \u201crace\u201d and ethnicity (especially in political discussions) is actually counterproductive, because the negative social consequences of modern \u201crace\u201d ideas could be ignored, making it harder to examine and address instances of discrimination properly (Wise 2010). Rather than shy away from these topics, we can use our scientific findings to establish socially relevant and biologically accurate ideas concerning human diversity. Today, research into genetic and phenotypic differentiation among and within various human populations continues to expand in its scope, its technological capabilities, its sample sizes, and its ethical concerns. It is thanks to such scientific work done in the past few decades that we now have a deeper understanding not only of how humans vary but also of how we are biologically a rather homogenous, intermixing world population.<\/p>\r\n\r\n<h2>Summary<\/h2>\r\nHistorically, most concepts of race were shaped by religious and early \u2018scientific\u2019 attempts to classify people, many of which justified inequality and racism. Today, biological anthropology emphasizes that human variation is continuous (clinal), polygenic, and shaped by both evolutionary pressures and neutral processes. Misunderstandings of race, however, continue to have serious social and medical consequences; evident in systemic racism and inequities in health care.\r\n\r\nBiological anthropologists now play a critical role in discrediting myths about race. By studying\u00a0 human variation, we can begin to understand evolutionary processes, adaptation, and the social implications of differences among human populations. Modern research shows that that humans are far more genetically homogenous than many other species, reinforcing a conclusion that \u2018race\u2019 is not a biological reality but a powerful social construct with real effects. Through evolutionary history and genetics, human diversity can be researched and understood, rather than than through racial categories.\r\n<div class=\"textbox shaded\">\r\n<h2 class=\"import-Normal\">Review Questions<\/h2>\r\n<ul>\r\n \t<li class=\"import-Normal\">How is the genetic variation of the human species distributed worldwide?<\/li>\r\n \t<li class=\"import-Normal\">What evolutionary processes are responsible for producing genotypic\/phenotypic variation within and between human populations?<\/li>\r\n \t<li class=\"import-Normal\">Should we continue to attribute any value to \u201crace\u201d concepts older than 1950, based on our current understandings of human biological variation?<\/li>\r\n \t<li class=\"import-Normal\">How should we communicate scientific findings about human biological variation more accurately and responsibly to those outside the anthropological discipline?<\/li>\r\n<\/ul>\r\n<\/div>\r\n<h2 class=\"import-Normal\">Key Terms<strong>\r\n<\/strong><\/h2>\r\n<p class=\"import-Normal\"><strong>Age of Discovery<\/strong>: A period between the late 1400s and late 1700s when European explorers and ships sailed extensively across the globe in pursuit of new trading routes and territorial conquest.<\/p>\r\n<p class=\"import-Normal\"><strong>Ancestry<\/strong>: Biogeographical information about an individual, traced either through the study of an individual\u2019s genome, skeletal characteristics, or some other form of forensic\/archaeological evidence. Anthropologists carry out probabilistic estimates of ancestry. They attribute sets of human remains to distinctive \u201cancestral\u201d groups using careful statistical testing and should report ancestry estimations with statistical probability values.<\/p>\r\n<p class=\"import-Normal\"><strong>Binomial nomenclature<\/strong>: A system of naming living things developed by Linnaeus in the 1700s. It employs a scientific name made up of two italicized Latin or Greek words, with the first word capitalized and representative of an organism\u2019s genus and the second word indicating an organism\u2019s species (e.g., <em>Homo sapiens<\/em>, <em>Australopithecus afarensis<\/em>, <em>Pongo tapanuliensis<\/em>, etc.).<\/p>\r\n<p class=\"import-Normal\"><strong>Biological anthropology<\/strong>: A branch of study under anthropology (the study of humankind) that focuses on when and where humans and our human ancestors first originated, how we have evolved and adapted globally over time, and the reasons why we see biological variation among humans worldwide today.<\/p>\r\n<p class=\"import-Normal\"><strong>Biological determinism<\/strong>: The erroneous concept that an individual\u2019s behavioral characteristics are innate and determined by genes, brain size, or other physiological attributes\u2014and, notably, without the influence of social learning or the environment around the individual during development.<\/p>\r\n<p class=\"import-Normal\"><strong>Bony labyrinth<\/strong>: A system of interconnected canals within the auditory (ear- or hearing-related) apparatus, located in the inner ear and responsible for balance and the reception of sound waves.<\/p>\r\n<p class=\"import-Normal\"><strong>Cline<\/strong>: A gradient of physiological or morphological change in a single character or allele frequency among a group of species across environmental or geographical lines (e.g., skin color varies clinally, as, over many generations, human groups living nearer the equator have adapted to have more skin pigmentation).<\/p>\r\n<p class=\"import-Normal\"><strong>Continuous variation<\/strong>: This term refers to variation that exists between individuals and cannot be measured using distinct categories. Instead, differences between individuals within a population in relation to one particular trait are measurable along a smooth, continuous gradient.<\/p>\r\n<p class=\"import-Normal\"><strong>Cystic fibrosis<\/strong>: A genetic disorder in which one defective gene causes overproduction and buildup of mucus in the lungs and other bodily organs. It is most common in northern Europeans (but also occurs in other world populations).<\/p>\r\n<p class=\"import-Normal\"><strong>Ecological niche<\/strong>: The position or status of an organism within its community and\/or ecosystem, resulting from the organism\u2019s structural and functional adaptations (e.g., bipedalism, omnivorous diets, lactose digestion, etc.).<\/p>\r\n<p class=\"import-Normal\"><strong>Essentialism<\/strong>: A belief or view that an entity, organism, or human grouping has a specific set of characteristics that are fundamentally necessary to its being and classification into definitive categories.<\/p>\r\n<p class=\"import-Normal\"><strong>Ethnicity<\/strong>: A term used commonly in an interchangeable way with the term <em>race<\/em>, complicated because how different people define this term depends on the qualities and characteristics they use to assign a label or identity to themselves and\/or others (which may include aspects of family background, skin color, language(s) spoken, religion, physical proportions, behavior and temperament, etc.).<\/p>\r\n<p class=\"import-Normal\"><strong>Eugenics<\/strong>: A set of beliefs and practices that involves the controlled selective breeding of human populations with the hope of improving their heritable qualities, especially through surgical procedures like sterilization and legal rulings that affect marriage rights for interracial couples.<\/p>\r\n<p class=\"import-Normal\"><strong>Gene flow<\/strong>: A neutral (or nonselective) evolutionary process that occurs when genes get shared between populations.<\/p>\r\n<p class=\"import-Normal\"><strong>Genetic drift<\/strong>: A neutral evolutionary process in which allele frequencies change from generation to generation due to random chance.<\/p>\r\n<p class=\"import-Normal\"><strong>Heterogeneity<\/strong>: The quality of being diverse genetically.<\/p>\r\n<p class=\"import-Normal\"><strong>Homog<\/strong><strong>enous<\/strong>: The quality of being uniform genetically.<\/p>\r\n<p class=\"import-Normal\"><strong>Human diversity<\/strong>: Human diversity is a measure of variation that may describe how many different forms of human there are, separated or clustered into groups according to some genetic, phenotypic, or cultural trait(s). The term can be applied to culture (in which case humans can be described as significantly diverse) or genetics (in which case humans are not diverse because all humans on Earth share a majority of their genes).<\/p>\r\n<p class=\"import-Normal\"><strong>Human variation<\/strong>: Differences in biology, physiology, body chemistry, behavior, and culture. By measuring these differences, we understand the degrees of variation between individuals, groups, populations, or species.<\/p>\r\n<p class=\"import-Normal\"><strong>Isolation-by-distance model<\/strong>: A model that predicts a positive relationship between genetic distances and geographical distances between pairs of populations.<\/p>\r\n<p class=\"import-Normal\"><strong>Monogenetic<\/strong>: Pertaining to the idea that the origin of a species is situated in one geographic region or time (as opposed to <em>polygenetic<\/em>).<\/p>\r\n<p class=\"import-Normal\"><strong>Mutation<\/strong>: A gene alteration in the DNA sequence of an organism. As a random, neutral evolutionary process that occurs over the course of meiosis and early cell development, gene mutations are possible sources of variation in any given human gene pool. Genetic mutations that occur in more than 1% of a population are termed <em>polymorphisms<\/em>.<\/p>\r\n<p class=\"import-Normal\"><strong>Natural selection<\/strong>: An evolutionary process whereby certain traits are perpetuated through successive generations, likely owing to the advantages they give organisms in terms of chances of survival and\/or reproduction.<\/p>\r\n<p class=\"import-Normal\"><strong>Nonconcordance<\/strong>: The fact of genes or traits not varying with one another and instead being inherited independently.<\/p>\r\n<p class=\"import-Normal\"><strong>Otherness<\/strong>: In postcolonial anthropology, we now understand \u201cothering\u201d to mean any action by someone or some group that establishes a division between \u201cus\u201d and \u201cthem\u201d in relation to other individuals or populations. This could be based on linguistic or cultural differences, and it has largely been based on external characteristics throughout history.<\/p>\r\n<p class=\"import-Normal\"><strong>Out-of-Africa model<\/strong>: A model that suggests that all humans originate from one single group of <em>Homo sapiens<\/em> in (sub-Saharan) Africa who lived between 100,000 and 315,000 years ago and who subsequently diverged and migrated to other regions across the globe.<\/p>\r\n<p class=\"import-Normal\"><strong>Physical anthropology<\/strong>: This used to be the more common name given to the subdiscipline of anthropology centered upon the study of human origins, evolution and variation (also see <em>biological anthropology<\/em> above). This name for the field has gradually become less popular due to two reasons: first, it may not reflect our interests in other aspects of humankind that are not physical (such as those behavioral, cultural and spiritual), and second, using this term popular in the early decades of our field may be viewed by some as harkening back to a time when biological anthropologists conducted their work in unethical ways.<\/p>\r\n<p class=\"import-Normal\"><strong>Polygenetic<\/strong>: Having many different ancestries, as in older theories about human origins that involved multiple traditional groupings of humans evolving concurrently in different parts of the world before they merged into one species through interbreeding and\/or intergroup warfare. These earlier suggestions have now been overwhelmed by insurmountable evidence for a single origin of the human species in Africa (see the \u201cOut-of-Africa model\u201d).<\/p>\r\n<p class=\"import-Normal\"><strong>Polymorphism<\/strong>: A genetic variant within a population (caused either by a single gene or multiple genes) that occurs at a rate of over 1% among the population. Polymorphisms are responsible for variation in phenotypic traits such as blood type and skin color.<\/p>\r\n<p class=\"import-Normal\"><strong>Population<\/strong>: A group of humans living in a particular geographical area, with more local interbreeding within-group than interbreeding with other groups. A limited or restricted amount of gene flow between populations can occur due to geographical, cultural, linguistic, or environmental factors.<\/p>\r\n<p class=\"import-Normal\"><strong>Population bottlenecking<\/strong>: An event in which genetic variation is significantly reduced owing to a sharp reduction in population size. This can occur when environmental disaster strikes or as a result of human activities (e.g., genocides or group migrations). An important example of this loss in genetic variation occurred over the first human migrations out of Africa and into other continental regions.<\/p>\r\n<p class=\"import-Normal\"><strong>Prejudice<\/strong>: An unjustified attitude toward an individual or group that is not based on reason, whether positive (and showing preference for one group of people over another) or negative (and resulting in harm or injury to others).<\/p>\r\n<p class=\"import-Normal\"><strong>Race<\/strong>: The identification of a group based on a perceived distinctiveness that makes that group more similar to each other than they are to others outside the group. This may be based on cultural differences, genetic parentage, physical characteristics, behavioral attributes, or something arbitrarily and socially constructed. As a social or demographic category, perceptions of \u201crace\u201d can have real and serious consequences for different groups of people. This is despite the fact that biological anthropologists and geneticists have demonstrated that all humans are genetically homogenous and that more differences can be found within populations than between them in the overall apportionment of human biological variation. This term is sometimes used interchangeably with <em>ethnicity<\/em>.<\/p>\r\n<p class=\"import-Normal\"><strong>Racism<\/strong>: Any action or belief that discriminates against someone based on perceived differences in race or ethnicity.<\/p>\r\n<p class=\"import-Normal\"><strong>Scientific Revolution<\/strong>: A period between the 1400s and 1600s when substantial shifts occurred in the social, technological, and philosophical sense, when a scientific method based on the collection of empirical evidence through experimentation was emphasized and inductive reasoning was used to test hypotheses and interpret their results.<\/p>\r\n<p class=\"import-Normal\"><strong>Typolog<\/strong><strong>ical<\/strong>: Of or describing an assortment system that relies on the interpretation of qualitative similarities or differences in the study of variation among objects or people. The categorization of cultures or human groups according to \u201crace\u201d was performed with a typological approach in the earliest practice of anthropology, but this practice has since been discredited and abandoned.<\/p>\r\n<p class=\"import-Normal\"><strong>Variance<\/strong>: In statistics, variance measures the dispersal of a set of data around the mean or average value.<\/p>\r\n\r\n<h2 class=\"import-Normal\">For Further Exploration<strong>\r\n<\/strong><\/h2>\r\n<h3 class=\"import-Normal\"><strong>Videos<\/strong><\/h3>\r\nAmerican Medical Association (AMA). 2020. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=tqA3KvvscYc\" target=\"_blank\" rel=\"noopener\">Examining Race-Based Medicine<\/a>.\u201d YouTube, October 29. Accessed June 4, 2023.\r\n\r\nCrenshaw, Kimberl\u00e9. 2016. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=akOe5-UsQ2o\" target=\"_blank\" rel=\"noopener\">The Urgency of Intersectionality<\/a>.\u201d YouTube, December 7. Accessed June 4, 2023.\r\n\r\nGolash-Boza, Tanya. 2018. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=NQOimokvJXo\" target=\"_blank\" rel=\"noopener\">What Is Race? What Is Ethnicity? Is There a Difference?<\/a>.\u201d YouTube, October 28. Accessed June 4, 2023.\r\n\r\nLasisi, Tina. 2020. \u201c<a href=\"https:\/\/naturalhistory.si.edu\/education\/teaching-resources\/social-studies\/webinar-how-hair-reveals-futility-race-categories\" target=\"_blank\" rel=\"noopener\">How Hair Reveals the Futility of Race Categories<\/a>.\u201d National Museum of Natural History webinar, October 21.\r\n\r\nLasisi, Tina. 2022. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=_BEJvVFxKV4\" target=\"_blank\" rel=\"noopener\">Where Does My Skin Color Come From?<\/a>.\u201d PBS Terra, August 18. Accessed June 4, 2023.\r\n\r\nPBS Origins. 2018. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=CVxAlmAPHec\" target=\"_blank\" rel=\"noopener\">The Origin of Race in the USA<\/a>.\u201d YouTube, April 3. Accessed June 4, 2023.\r\n\r\nRoberts, Dorothy. 2016. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=KxLMjn4WPBY\" target=\"_blank\" rel=\"noopener\">The Problem with Race-Based Medicine<\/a>.\u201d YouTube, March 4. Accessed June 4, 2023.\r\n\r\nVox. 2015. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=VnfKgffCZ7U\" target=\"_blank\" rel=\"noopener\">The Myth of Race, Debunked in 3 Minutes<\/a>.\u201d YouTube, January 13. Accessed June 4, 2023.\r\n<h3 class=\"import-Normal\"><strong>Podcast Episodes<\/strong><\/h3>\r\nKwong, Emily, and Rebecca Ramirez. 2021. \u201c<a href=\"https:\/\/www.npr.org\/2021\/10\/05\/1043391809\/heres-a-better-way-to-talk-about-hair\" target=\"_blank\" rel=\"noopener\">Here\u2019s a Better Way to Talk about Hair: A 16 Minute Listen with Tina, Lasisi<\/a>\u201d NPR Short Wave, October 6. Accessed June 4, 2023.\r\n\r\nSpeaking of Race. 2020. \u201c<a href=\"https:\/\/soundcloud.com\/user-88955638\/sets\/race-and-health?fbclid=IwAR2U1jdQL3XYFS5llGvYZ6uSrvPikuakmbxUZb--8voxgAMKrLbu7Ym7LGU\" target=\"_blank\" rel=\"noopener\">Race and Health series<\/a>.\u201d Speaking of Race, April 10. Accessed June 4, 2023.\r\n<h3 class=\"import-Normal\"><strong>Websites<\/strong><\/h3>\r\nChoices Program. 2023. \u201c<a href=\"https:\/\/www.choices.edu\/teaching-news-lesson\/an-interactive-timeline-black-activism-and-the-long-fight-for-racial-justice\/\" target=\"_blank\" rel=\"noopener\">An Interactive Timeline: Black Activism and the Long Fight for Racial Justice<\/a>.\u201d <em>Choices Program, Brown University<\/em> [Interactive Timeline], Updated February, 2023.\r\n<h2 class=\"import-Normal\">References<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">American Association of Biological Anthropologists. 2020. \u201c<a href=\"https:\/\/bioanth.org\/about\/position-statements\/open-letter-our-community-response-police-brutality-against-african-americans-and-call-antiracist-action\/\" target=\"_blank\" rel=\"noopener\">An Open Letter to Our Community in Response to Police Brutality against African-Americans and a Call to Antiracist Action<\/a>\u201d. <em>American Association of Biological Anthropologists<\/em>, June 10, 2020. Accessed June 4, 2023.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Antrosio, Jason. 2011. \u201c\u2018<a href=\"https:\/\/www.livinganthropologically.com\/biological-anthropology\/race-reconciled-debunks-race\/\" target=\"_blank\" rel=\"noopener\">Race Reconciled\u2019: Race Isn\u2019t Skin Color, Biology, or Genetics<\/a>.\u201d <em>Living Anthropologically <\/em>(website), June 5, 2011; updated May 20, 2020. Accessed June 4, 2023.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Beals, Kenneth L., Courtland L. Smith, Stephen M. Dodd, J. Lawrence Angel, Este Armstrong, Bennett Blumenberg, Fakhry G. Girgis, et al. 1984. \u201cBrain Size, Cranial Morphology, Climate, and Time Machines [and Comments and Reply].\u201d <em>Current Anthropology<\/em> 25 (3): 301\u2012330.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Fran\u00e7ois Balloux, Tsunehiko Hanihara, and Andrea Manica. 2010. \u201cThe Relative Role of Drift and Selection in Shaping the Human Skull.\u201d <em>American Journal of Physical Anthropology<\/em> 141 (1): 76\u201282. https:\/\/doi.org\/10.1002\/ajpa.21115.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Fran\u00e7ois Balloux, William Amos, Tsunehiko Hanihara, and Andrea Manica. 2009. \u201cDistance from Africa, Not Climate, Explains Within-Population Phenotypic Diversity in Humans.\u201d <em>Proceedings: Biological Sciences<\/em> 276 (1658): 809\u2012814. https:\/\/doi.org\/10.1098\/rspb.2008.1563.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Noreen von Cramon-Taubadel, Andrea Manica, and Stephen J. Lycett. 2013. \u201cGlobal Geometric Morphometric Analyses of the Human Pelvis Reveal Substantial Neutral Population History Effects, Even across Sexes.\u201d <em>PloS ONE<\/em> 8 (2): e55909. https:\/\/doi.org\/10.1371\/journal.pone.0055909.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Noreen von Cramon-Taubadel, Andrea Manica, and Stephen J. Lycett. 2014. \u201cThe Interaction of Neutral Evolutionary Processes with Climatically Driven Adaptive Changes in the 3D Shape of the Human Os Coxae.\u201d <em>Journal of Human Evolution<\/em> 73 (August): 64\u201274. https:\/\/doi.org\/10.1016\/j.jhevol.2014.02.021.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Boas, Franz. 1931. \u201cRace and Progress.\u201d <em>Science<\/em> 74 1905): 1\u20128.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Bowden, Rory, Tammie S. MacFie, Simon Myers, Garrett Hellenthal, Eric Nerrienet, Ronald E. Bontrop, Colin Freeman, Peter Donnelly, and Nicholas I. Mundy. 2012. \u201cGenomic Tools for Evolution and Conservation in the Chimpanzee: <em>Pan troglodytes ellioti<\/em> Is a Genetically Distinct Population.\u201d <em>PLoS Genetics<\/em> 8 (3): e1002504. https:\/\/doi.org\/10.1371\/journal.pgen.1002504.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Campbell, Michael C., and Sarah A. Tishkoff. 2008. \u201cAfrican Genetic Diversity: Implications for Human Demographic History, Modern Human Origins, and Complex Disease Mapping.\u201d <em>Annual Review of Genomics and Human Genetics<\/em> 9: 403\u2012433.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Clee, Paul R. Sesink, Ekwoge E. Abwe, Ruffin D. Ambahe, Nicola M. Anthony, Roger Forso, Sabrina Locatelli, Fiona Maisels, et al. 2015. \u201cChimpanzee Population Structure in Cameroon and Nigeria Is Associated with Habitat Variation That May Be Lost Under Climate Change.\u201d <em>BMC Evolutionary Biology<\/em> 15: 2. https:\/\/doi.org\/10.1186\/s12862-014-0275-z.<\/p>\r\n<p class=\"import-Normal\">Cullors, Patrisse. 2016. \u201cAn Interview with the Founders of Black Lives Matter.\u201d TED Talks 2016, October 26\u201228. Accessed June 15, 2023. https:\/\/www.ted.com\/talks\/alicia_garza_patrisse_cullors_and_opal_tometi_an_interview_with_the_founders_of_black_lives_matter\/up-next.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Fuentes, Agust\u00edn, Rebecca Rogers Ackermann, Sheela Athreya, Deborah Bolnick, Tina Lasisi, Sang-Hee Lee, Shay-Akil McLean, and Robin Nelson. 2019. \u201cAAPA Statement on Race and Racism.\u201d <em>American Journal of Physical Anthropology<\/em> 169 (3): 400\u2012402.<\/p>\r\n<p class=\"import-Normal\">Garza, Alicia. 2016. \u201cAn Interview with the Founders of Black Lives Matter.\u201d TED Talks 2016, October 26\u201228. Accessed June 15, 2023. https:\/\/www.ted.com\/talks\/alicia_garza_patrisse_cullors_and_opal_tometi_an_interview_with_the_founders_of_black_lives_matter\/up-next.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Gerbault, Pascale, Anke Liebert, Yuval Itan, Adam Powell, Mathias Currat, Joachim Burger, Dallas M. Swallow, and Mark G. Thomas. 2011. \u201cEvolution of Lactase Persistence: An Example of Human Niche Construction.\u201d <em>Philosophical Transactions of the Royal Society B<\/em> 366 (1566): 863\u2012877. https:\/\/doi.org\/10.1098\/rstb.2010.0268.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Hooton, Earnest A. 1936. \u201cPlain Statements about Race.\u201d <em>Science<\/em> 83 (2161): 511\u2012513.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Hrdli\u010dka, Ale\u0161. 1918. \u201cPhysical Anthropology: Its Scope and Aims; Its History and Present Status in America. A: Physical Anthropology; Its Scopes and Aims.\u201d <em>American Journal of Physical Anthropology<\/em> 1 (1): 3\u201223.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Huxley, Julian. 1942. <em>Evolution: The Modern Synthesis<\/em>. London: Allen and Unwin.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ingram, Catherine J. E., Charlotte A. Mulcare, Yuval Itan, Mark G. Thomas, and Dallas M. Swallow. 2009. \u201cLactose Digestion and the Evolutionary Genetics of Lactase Persistence.\u201d <em>Human Genetics<\/em> 124 (6): 579\u2012591. https:\/\/doi.org\/10.1007\/s00439-008-0593-6.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Jablonski, Nina G. 2004. \u201cThe Evolution of Human Skin and Skin Color.\u201d <em>Annual Review of Anthropology<\/em> 33: 585\u2012623. https:\/\/doi.org\/10.1146\/annurev.anthro.33.070203.143955.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Jablonski, Nina G., and George Chaplin. 2000. \u201cThe Evolution of Human Skin Coloration.\u201d <em>Journal of Human Evolution<\/em> 39 (1): 57\u2012106. https:\/\/doi.org\/10.1006\/jhev.2000.0403.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Kanitz, Ricardo, Elsa G. Guillot, Sylvain Antoniazza, Samuel Neuenschwander, and J\u00e9r\u00f4me Gedout. 2018. \u201cComplex Genetic Patterns in Human Arise from a Simple Range-Expansion Model over Continental Landmasses.\u201d <em>PLoS ONE<\/em> 13 (2): e0192460.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Kronenberg, Zev N., Ian T. Fiddes, David Gordon, Shwetha Murali, Stuart Cantsilieris, Olivia S. Meyerson, Jason G. Underwood, et al. 2018. \u201cHigh-Resolution Comparative Analysis of Great Ape Genomes.\u201d <em>Science<\/em> 360 (6393): eaar6343. https:\/\/doi.org\/10.1126\/science.aar6343.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Kuzawa, Christopher W., and Elizabeth Sweet. 2009. \u201cEpigenetics and the Embodiment of Race: Development Origins of US Racial Disparities in Cardiovascular Health.\u201d <em>American Journal of Human Biology<\/em> 21 (1) : 2\u201215.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Lasisi, Tina, and Mark D. Shriver. 2018. \u201cFocus on African Diversity Confirms Complexity of Skin Pigmentation Genetics.\u201d <em>Genomic Biology<\/em> 19: 13.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Lewontin, Richard. 1972. \u201cThe Apportionment of Human Diversity.\u201d In <em>Evolutionary Biology<\/em>, vol. 6, edited by Theodosius Dobzhansky, Max K. Hecht, and William C. Steere, 381\u2012398. New York: Springer.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Linnaeus, Carl. 1758. <em>Systema Naturae<\/em>. Stockholm: Laurentius Salvius. <a class=\"rId128\" href=\"https:\/\/www.cabdirect.org\/abstracts\/20057000018.html\">https:\/\/www.cabdirect.org\/abstracts\/20057000018.html<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Liu, Hua, Franck Prugnolle, Andrea Manica, and Fran\u00e7ois Balloux. 2006. \u201cA Geographically Explicit Genetic Model of Worldwide Human-Settlement History.\u201d <em>American Journal of Human Genetics<\/em> 79 (2): 230\u2012237.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Livingstone, Frank B. 1962. \u201cOn the Nonexistence of Human Races.\u201d <em>Current Anthropology<\/em> 3 (3): 279\u2012281.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Long, Jeffery C., and Rick A. Kittles. 2003. \u201cHuman Genetic Diversity and the Nonexistence of Biological Races.\u201d <em>Human Biology<\/em> 75 (4): 449\u2012471.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Luzzatto, Lucio. 2012. \u201cSickle Cell Anaemia and Malaria.\u201d <em>Mediterranean Journal of Hematology and Infectious Diseases<\/em> 4 (1). https:\/\/doi.org\/10.4084\/MJHID.2012.065.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Manica, Andrea, William Amos, Fran\u00e7ois Balloux, and Tsunehiko Hanihara. 2007. \u201cThe Effect of Ancient Population Bottlenecks on Human Phenotypic Variation.\u201d <em>Nature<\/em> 448 (7151): 346\u2012348. https:\/\/doi.org\/10.1038\/nature05951.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">McLean, Shay-Akil. 2014. \u201c\u2018Race, Ethnicity, &amp; Racism.\u201d Decolonize ALL The Things Website, Accessed January 10, 2023. https:\/\/decolonizeallthethings.com\/learning-tools\/race-ethnicity-racism\/.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Morton, Samuel George. 1839. <em>Crania Americana, or, A Comparative View of the Skulls of Various Aboriginal Nations of North and South America.<\/em> Philadelphia: J. Dobson.<\/p>\r\n<p class=\"import-Normal\">Mourant, A. E., Ada C. Kope\u0107, and Kazimiera Domaniewska-Sobczak. 1976. <em>The Distribution of the Human Blood Groups and Other Polymorphisms<\/em>, 2nd edition. Oxford: Oxford University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">National Research Council (U.S.) Committee on Human Genome Diversity. 1997. <em>Evaluating Human Genetic Diversity.<\/em> Washington, D.C.: National Academies Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Omi, Michael, and Howard Winant. 2014. \u201cThe Theory of Racial Formation.\u201d In <em>Racial Formation in the United States<\/em>,3rd edition, edited by Michael Omi and Howard Winant, 105\u2012126. Routledge: New York.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Osada, Naoki. 2015. \u201cGenetic Diversity in Humans and Non-Human Primates and Its Evolutionary Consequences.\u201d <em>Genes and Genetic Systems<\/em> 90 (3): 133\u2012145.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ousley, Stephen D., Richard L. Jantz, and Donna Freid. 2009. \u201cUnderstanding Race and Human Variation: Why Forensic Anthropologists Are Good at Identifying Race.\u201d <em>American Journal of Physical Anthropology<\/em> 139 (1): 68\u201276. https:\/\/doi.org\/10.1002\/ajpa.21006.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ponce de Le\u00f3n, Marcia S., Toetik Koesbardiati, John David Weissmann, Marco Millela, Carlos S. Reyna-Blanco, Gen Suwa, Osamu Kondo, Anna-Sapfo Malaspinas, Tim D. White, and Christoph P. E. Zollikofer. 2018. \u201cHuman Bony Labyrinth Is an Indicator of Population History and Dispersal from Africa.\u201d <em>Proceedings of the National Academy of Sciences<\/em> 115 (16): 4128\u20124133. https:\/\/doi.org\/10.1073\/pnas.1808125115.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Prado-Martinez, Javier, Peter H. Sudmant, Jeffrey M. Kidd, Heng Li, Joanna L. Kelley, Belen Lorente-Galdos, Krishna R. Veeramah, et al. 2013. \u201cGreat Ape Genetic Diversity and Population History.\u201d <em>Nature<\/em> 499 (7459): 471\u2013475. https:\/\/doi.org\/10.1038\/nature12228.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Prugnolle, Franck, Andrea Manica, and Fran\u00e7ois Balloux. 2005. \u201cGeography Predicts Neutral Genetic Diversity of Human Populations.\u201d <em>Current Biology<\/em> 15 (5): 159\u2012160.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Quillen, Ellen E., Heather L. Norton, Esteban J. Parra, Frida Lona-Durazo, Khai C. Ang, Florin Mircea Illiescu, Laurel N. Pearson, et al. 2018. \u201cShades of Complexity: New Perspectives on the Evolution and Genetic Architecture of Human Skin.\u201d <em>American Journal of Physical Anthropology<\/em> 168 (S67): 4\u201326.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Rathmann, Hannes, Hugo Reyes-Centeno, Silvia Ghirotto, Nicole Creanza, Tsunehiko Hanihara, and Katerina Harvati. 2017. \u201cReconstructing Human Population History from Dental Phenotypes.\u201d <em>Scientific Reports<\/em> 7: 12495. https:\/\/doi.org\/10.1038\/s41598-017-12621-y.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2001. \u201cGlobal Analysis of Regional Differences in Craniometric Diversity and Population Substructure.\u201d <em>Human Biology<\/em> 73 (5): 629\u2012636. https:\/\/doi.org\/10.1353\/hub.2001.0073.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2002. \u201cApportionment of Global Human Genetic Diversity Based on Craniometrics and Skin Color.\u201d <em>American Journal of Physical Anthropology<\/em> 118 (4): 393\u2012398. https:\/\/doi.org\/10.1002\/ajpa.10079.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2004. \u201cGlobal Patterns of Isolation by Distance Based on Genetic and Morphological Data.\u201d <em>Human Biology<\/em> 76 (4): 499\u2012513. https:\/\/doi.org\/10.1353\/hub.2004.0060.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2009. \u201cRace and Global Patterns of Phenotypic Variation.\u201d <em>American Journal of Physical Anthropology<\/em> 139 (1): 16\u201222. https:\/\/doi.org\/10.1002\/ajpa.20900.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Roberts, Dorothy. 2013. <em>Fatal Invention: How Science, Politics, and Big Business Re-Create Race in the Twenty-First Century<\/em>. New York: The New Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Rosenberg, Noah A., Saurabh Mahajan, Sohini Ramachandran, Chengfeng Zhao, Jonathan K. Pritchard, and Marcus W. Feldman. 2005. \u201cClines, Clusters, and the Effect of Study Design on the Inference of Human Population Structure.\u201d <em>PLoS Genetics<\/em> 1 (6): e70. https:\/\/doi.org\/10.1371 \/journal.pgen.0010070.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Rosenberg, Noah A., Jonathan K. Pritchard, James L. Weber, Howard M. Cann, Kenneth K. Kidd, Lev A. Zhivotovsky, and Marcus W. Feldman. 2002. \u201cGenetic Structure of Human Populations.\u201d <em>Science<\/em> 298 (5602): 2381\u20122385.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Sauer, Norman J. 1992. \u201cForensic Anthropology and the Concept of Race: If Races Don\u2019t Exist, Why Are Forensic Anthropologists So Good at Identifying Them?\u201d <em>Social Science and Medicine<\/em> 34 (2): 107\u2012111. https:\/\/doi.org\/10.1016\/0277-9536(92)90086-6.<\/p>\r\n<p class=\"import-Normal\">Shonkoff, Jack P., Natalie Slopen, and David R. Williams. 2021. \u201cEarly Childhood Adversity, Toxic Stress, and the Impacts of Racism on the Foundations of Health.\u201d <em>Annual Review of Public Health<\/em> 42: 115\u2012134.<\/p>\r\n<p class=\"import-Normal\">Sjoding, Michael W., Robert P. Dickson, Theodore J. Iwashyna, Steven E. Gay, and Thomas S. Valley. 2020. \u201cRacial Bias in Pulse Oximetry Measurement.\u201d <em>The New England Journal of Medicine<\/em> 383: 2477-2478.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Staes, Nicky, Chet C. Sherwood, Katharine Wright, Marc de Manuel, Elaine E. Guevara, Tomas Marques-Bonet, Michael Kr\u00fctzen, et al. 2017. \u201cFOXP2 Variation in Great Ape Populations Offers Insight into the Evolution of Communication Skills.\u201d <em>Scientific Reports<\/em> 7 (1): 1\u201210. https:\/\/doi.org\/10.1038\/s41598-017-16844-x.<\/p>\r\n<p class=\"import-Normal\">Tomati, Opal. 2016. \u201cAn Interview with the Founders of Black Lives Matter.\u201d TED Talks 2016, October 26\u201228. Accessed June 15, 2023. https:\/\/www.ted.com\/talks\/alicia_garza_patrisse_cullors_and_opal_tometi_an_interview_with_the_founders_of_black_lives_matter\/up-next.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Tsai, Jennifer. 2021. \u201cCOVID-19 Is Not a Story of Race, but a Record of Racism\u2014Our Scholarship Should Reflect That Reality.\u201d <em>The American Journal of Bioethics<\/em> 21 (2): 43\u201247. https:\/\/doi.org\/10.1080\/15265161.2020.1861377.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">von Cramon-Taubadel, Noreen, and Stephen J. Lycett. 2008. \u201cBrief Communication: Human Cranial Variation Fits Iterative Founder Effect Model with African Origin.\u201d <em>American Journal of Physical Anthropology<\/em> 136 (1): 108\u2012113. https:\/\/doi.org\/10.1002\/ajpa.20775.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Weiss, Kenneth M., and Jeffrey C. Long. 2009. \u201cNon-Darwinian Estimation: My Ancestors, My Genes\u2019 Ancestors.\u201d <em>Genome Research<\/em> 19: 703\u2012710. https:\/\/doi.org\/10.1101\/gr.076539.108.19.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Williams, David W. 2018. \u201cStress and the Mental Health of Populations of Color: Advancing Our Understanding of Race-related Stressors.\u201d <em>Journal of Health and Social Behavior<\/em> 59 (4): 466\u2012485.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Wise, Tim. 2010. <em>Colorblind: The Rise of Post-Racial Politics and the Retreat from Racial Equity<\/em>. San Francisco: City Lights.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Yudell, Michael, Dorothy Roberts, Rob DeSalle, and Sarah Tishkoff. 2016. \u201cTaking Race out of Human Genetics.\u201d <em>Science<\/em> 351 (6273): 564\u2012565. https:\/\/doi.org\/10.1126\/science.aac4951.<\/p>\r\n\r\n<\/div>","rendered":"<div class=\"__UNKNOWN__\">\n<p class=\"import-Normal\">Michael B. C. Rivera, Ph.D., University of Cambridge<\/p>\n<p class=\"import-Normal\"><em>This chapter is a revision from <\/em><em>&#8220;<\/em><a class=\"rId7\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-12\/\"><em>Chapter 13: Race and Human Variation<\/em><\/a><em>\u201d by Michael B. C. Rivera. In <\/em><a class=\"rId8\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\"><em>Explorations: An Open Invitation to Biological Anthropology, first edition<\/em><\/a><em>, edited by Beth Shook, Katie Nelson, Kelsie Aguilera, and Lara Braff, which is licensed under <\/em><a class=\"rId9\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\"><em>CC BY-NC 4.0<\/em><\/a><em>. <\/em><\/p>\n<div class=\"textbox textbox--learning-objectives\">\n<header class=\"textbox__header\">\n<h2 class=\"textbox__title\"><span style=\"color: #000000\">Learning Objectives<\/span><\/h2>\n<\/header>\n<div class=\"textbox__content\">\n<ul>\n<li>Illustrate the troubling history of \u201crace\u201d concepts.<\/li>\n<li>Explain human variation and evolution as the thematic roots of biological anthropology as a discipline.<\/li>\n<li>Critique earlier \u201crace\u201d concepts based on a contemporary understanding of the apportionment of human genetic variation.<\/li>\n<li>Explain how biological variation in humans is distributed clinally and in accordance with both isolation-by-distance and Out-of-Africa models.<\/li>\n<li>Identify phenotypic traits that reflect selective and neutral evolution.<\/li>\n<li>Extend this more-nuanced view of human variation to today\u2019s research, the implications for biomedical studies, applications in forensic anthropology, and other social\/cultural\/political concerns.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<p>Humans exhibit biological variation. Humans also have a universal desire to categorize other humans in order to make sense of the world around them. Since the birth of the discipline of <strong>biological anthropology, <\/strong>we have been interested in studying how humans vary biologically and what the sources of this variation are. Before we tackle these big problems, first consider this question: Why <em>should<\/em> we study human variation?<\/p>\n<figure style=\"width: 429px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2023\/06\/image26-3.png\" alt=\"Culturally and biologically diverse humans.\" width=\"429\" height=\"429\" \/><figcaption class=\"wp-caption-text\">Figure 14.1: Humans are culturally diverse (in that cultural differences contribute to a great degree of variation between individuals), but those shown are genetically undiverse. (Top left: Hadzabe members in Tanzania; top right: Inuit family; bottom left: Andean man in Peru; bottom right: English woman.) Credit: <a class=\"rId11\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-12\/\">Humans are diverse (Figure 13.1)<\/a> original to <a class=\"rId12\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Michael Rivera is a collective work under a <a class=\"rId13\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc-sa\/4.0\/\">CC BY-NC-SA 4.0<\/a> license. [Includes <a class=\"rId14\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Tanzania_-_Hadzabe_hunter_(14533536392).jpg\">Tanzania &#8211; Hadzabe hunter (14533536392)<\/a> by <a class=\"rId15\" href=\"https:\/\/www.flickr.com\/people\/67947877@N06\">A_Peach<\/a>, <a class=\"rId16\" href=\"https:\/\/creativecommons.org\/licenses\/by\/2.0\/legalcode\">CC BY 2.0<\/a>; <a class=\"rId17\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Inuit-Kleidung_1.jpg\">Inuit-Kleidung 1<\/a> by Ansgar Walk, <a class=\"rId18\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0<\/a>; <a class=\"rId19\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Andean_Man.jpg\">Andean Man<\/a> by <a class=\"rId20\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Cacophony\">Cacophony<\/a>, <a class=\"rId21\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0<\/a>; <a class=\"rId22\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Jane_Goodall_GM.JPG\">Jane Goodall GM<\/a> by <a class=\"rId23\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Floatjon\">Floatjon<\/a>, <a class=\"rId24\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">There are certainly academic reasons for studying human variation. First, it is highly interesting and important to consider the evolution of our species (see Chapters 9\u201312) and how our biological variation may be similar to (or different from) that of other species (e.g., other primates and apes; see Chapters 5 and 6). Second, anthropologists study modern human variation to understand how different biological traits developed over evolutionary time (see Figure 14.1). Suppose we are able to grasp the evolutionary processes that produce the differences in biology, physiology, body chemistry, behavior, and culture (<strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_410_804\">human variation<\/a><\/strong>). In that case, we can make more accurate inferences about evolution and adaptation among our hominin ancestors, complementing our study of fossil evidence and the archaeological record. Third, as will be discussed in more detail later on, it is important to consider that biological variation among humans has biomedical, forensic, and sociopolitical implications. For these reasons, the study of human variation and evolution has formed the basis of anthropological inquiry for centuries and continues to be a major source of intrigue and inspiration for scientific research conducted today.<\/p>\n<p class=\"import-Normal\">An even-more-important role of the biological anthropologist is to improve public understanding of human evolution and variation\u2014outside of academic circles. Terms such as <strong>race<\/strong> and <strong>ethnicity<\/strong> are used in everyday conversations and in formal settings within and outside academia. The division of humankind into smaller, discrete categories is a regular occurrence in day-to-day life. This can be seen regularly when governments acquire census data with a heading like \u201cgeographic origin\u201d or \u201cethnicity.\u201d Furthermore, such checkboxes and drop-down lists are commonly seen as part of the identifying information required for surveys and job applications.<\/p>\n<p class=\"import-Normal\">According to professors of anthropology, ethnic studies, and sociology, race is often understood as rooted in biological differences, ranging from such familiar traits as skin color or eye shape to variations at the genetic level. However, race can also be studied as an \u201cideological construct\u201d that goes beyond biological and genetic bases (Fuentes et al. 2019), at different times relating to our ethnicities, languages, religious beliefs, and cultural practices. Sometimes people associate racial identity with the concept of socioeconomic status or position, or they link ideas about race to what passport someone has, how long they have been in a country, or how well they have \u201cintegrated\u201d into a population.<\/p>\n<p class=\"import-Normal\">Some of these ideas about ethnicity have huge social and political impacts, and notions of race have been part of the motivation behind various forms of racism and prejudice today, as well as many wars and genocides throughout history. <strong>Racism<\/strong> manifests in many ways\u2014from instances of bullying between kids on school playgrounds to underpaid minorities in the workforce, and from verbal abuse hurled at people of color to violent physical behaviors against those of a certain race. <strong>Prejudice<\/strong> can be characterized as negative views toward another group based on some perceived characteristic that makes all members of that group worthy of disdain, disrespect, or exclusion (not solely along racial lines but also according to [dis]ability, gender, sexual orientation, or socioeconomic background, for example). According to Shay-Akil McLean (2014), \u201cRacism is not something particular to the United States and race is not the same everywhere in the world. Racial categories serve particular contextual purposes depending on the society they are used in, but generally follow the base logic of the supremacy of one type of human body over all others (ordering these human bodies in a hierarchical fashion).\u201d Choosing which biological or nonbiological features to use when discussing race is always a social process (Omi and Winant 2014). Race concepts have no validity to them unless people continue to use them in their daily lives\u2014and, in the worst cases, to use them to justify racist behaviors and problematic ideas about racial difference or superiority\/inferiority. Recent work in anthropological genetics has revealed the similarities amongst humans on a molecular level and the relatively few differences that exist between populations (Omi and Winant 2014).<\/p>\n<p class=\"import-Normal\">The role of the biological anthropologist becomes crucial in the public sphere, because we may be able to debunk myths surrounding human variation and shed light, for the nonanthropologists around us, on how human variation is actually distributed worldwide (see Figure 14.1). Rooted in scientific observations, our work can help nonanthropologists recognize how common ideas about \u201crace\u201d often have no biological or genetic basis. Many anthropologists work hard to educate students on the history of where race concepts come from, why and how they last in public consciousness, and how we become more conscious of racial issues and the need to fight against racism in our societies. Throughout this chapter, I will highlight how humans cannot actually be divided into discrete \u201craces,\u201d because most traits vary on a continuous basis and human biology is, in fact, very <strong>homogenous<\/strong> compared to the greater genetic variation we observe in closely related species. Molecular anthropology, or anthropological genetics, continues to add new layers to our understanding of human biological variation and the evolutionary processes that gave rise to the contemporary patterns of human variation. The study of human variation has not always been unbiased, and thinkers and scientists have always worked in their particular sociohistorical context. For this reason, this chapter opens with a brief overview of race concepts throughout history, many of which relied on unethical and unscientific notions about different human groups.<\/p>\n<\/div>\n<div class=\"textbox\">\n<h2 class=\"import-Normal\">Special Topic: My Experiences as an Asian Academic<\/h2>\n<figure style=\"width: 578px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image10-4.jpg\" alt=\"Outdoor photo of this chapter\u2019s author.\" width=\"578\" height=\"433\" \/><figcaption class=\"wp-caption-text\">Figure 14.2: Michael B. C. Rivera in Hong Kong. Credit: Michael B. C. Rivera in Hong Kong original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) is under a <a class=\"rId26\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p>My name is Michael, and I am a biological anthropologist and archaeologist (Figure 14.2). What strikes me as most interesting to investigate is human biological variation today and the study of past human evolution. For instance, some of my research on ancient coastal populations has revealed positive effects of coastal living on dietary health and many unique adaptations in bones and teeth when living near rivers and beaches. I love talking to students and nonscientists about bioanthropologists\u2019 work, through teaching, science communication events, and writing book chapters like this one. I grew up in Hong Kong, a city in southern China. My father is from the Philippines and my mother is from Hong Kong, which makes me a mixed Filipino-Chinese academic. Growing up, I noticed that people came in all shapes, sizes, and colors. My life is very different now in that I have gained the expertise to explain those differences, and I feel a great responsibility to guide those new to anthropology toward their own understandings of diversity.<\/p>\n<p class=\"import-Normal\">Biological anthropology is not taught extensively in Hong Kong, so I moved to the United Kingdom to earn my bachelor\u2019s, master\u2019s, and doctorate degrees. It was fascinating to me that we could answer important questions about human variation and history using scientific methods. However, I did not have many minority academic role models to look up to while I was at university. My department was made up almost exclusively of white westerner faculty, and it was hard to imagine I could one day get a job at these western institutions. While pursuing my degrees, I also remember several instances of my research contributions being overlooked or dismissed. Sometimes professors and fellow students would make racist comments toward Asian scholars (including me) and other Black, Indigenous and researchers of color, making us greatly uncomfortable in those spaces. When one of us would work up the courage to tell university leaders our experiences of being stereotyped, dismissed, or insulted, we received little support and were further excluded from research and teaching activities. This is a common experience for Black, Indigenous, and other people of color who pursue biological anthropology, and we face the difficult choice between leaving the field or bearing with such unsafe spaces.<\/p>\n<p class=\"import-Normal\">It became important to me at that time to find other academics of color with whom to share experiences and form community. I feel inspired by all my colleagues who advocate for greater representation and diversity in universities (whether they are minority academics or not). I admire many of my fellow researchers who are underrepresented and do a great job of representing minority groups through their cutting-edge research and quality teaching at the undergraduate and graduate levels. Although I no longer work in the West, it has remained my great hope that those in the West and the \u201cGlobal North\u201d will continue to improve university culture, and I support any efforts there to welcome all scholars.<\/p>\n<p class=\"import-Normal\">My current work is based in Hong Kong, where I am deeply dedicated to helping develop biological anthropology in East and Southeast Asia and promoting research from our home regions on the international scene. The study of anthropology really highlights how we share a common humanity and history. Being somebody who is \u201cmixed race\u201d and Asian likely played a key role in steering me toward the study of human variation. As this chapter hopefully shows, there is a lot to discuss about race and ethnicity regarding the discipline\u2019s history and current understandings of <strong>human diversity<\/strong>. Some scientific and technological advancements today are misused for reasons to do with money, politics, or the continuation of antiquated ideas. It is my belief, alongside many of my friends and fellow anthropologists, that science should be more about empathy toward all members of our species and contributing to the intellectual and technological nourishment of society. After speaking to many members of the public, as well as my own undergraduate students, I have received lovely messages from other individuals of color expressing thanks and appreciation for my presence and understanding as a minority scientist and mentor figure. Anthropology needs much more diversity as well as to make room for those who have traveled different routes into the discipline. All paths taken into anthropology are valid and valuable. I would encourage everyone to study anthropology\u2014it is a field for understanding and celebrating the intricacies of human diversity.<\/p>\n<\/div>\n<div class=\"__UNKNOWN__\">\n<h2 class=\"import-Normal\">The History of &#8220;Race&#8221; Concepts<\/h2>\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d in the Classical Era<\/strong><\/h3>\n<figure style=\"width: 435px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image11-8.png\" alt=\"Painting of four individuals with varied skin colors, head hair, facial hair, and clothing styles.\" width=\"435\" height=\"331\" \/><figcaption class=\"wp-caption-text\">Figure 14.3: (From left to right) Depicting a Berber (Libyan), a Nubian, an Asiatic (Levantine), and an Egyptian, copied from a mural on the tomb of Seti I. Credit: Egyptian races drawing by Heinrich von Minutoli (1820) of a mural by an unknown artist from the tomb of Seti I is in the public domain.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The earliest classification systems used to understand human variation are evidenced by ancient manuscripts, scrolls, and stone tablets recovered through archaeological, historical, and literary research. The Ancient Egyptians had the <em>Book of Gates<\/em>, dated to the New Kingdom between 1550 B.C.E. and 1077 B.C.E (Figure 14.3). In one part of this tome dedicated to depictions of the underworld, scribes used pictures and hieroglyphics to illustrate a division of Egyptian people into the four categories known to them at the time: the Aamu (Asiatics), the Nehesu (Nubians), the Reth (Egyptians), and the Themehu (Libyans). Though not rooted in any scientific basis like our current understandings of human variation today, the Ancient Egyptians believed that each of these groups were made of a distinctive category of people, distinguishable by their skin color, place of origin, and even behavioral traits.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Another well-known early document is the Bible, where it is written that all humankind descends from one of three sons of Noah: Shem (the ancestor to all olive-skinned Asians), Japheth (the ancestor to pale-skinned Europeans), and Ham (the ancestor to darker-skinned Africans). Similar to the Ancient Egyptians, these distinctions were based on behavioral traits and skin color. More recent work in historiography and linguistics suggest that the branches of \u201cHamites,\u201d \u201cJaphethites,\u201d and \u201cShemites\u201d may also relate to the formation of three independent language groups some time between 1000 and 3000 B.C.E. With the continued proliferation of Christianity, this concept of approximately three racial groupings lasted until the Middle Ages and spread as far across Eurasia as crusaders and missionaries ventured at the time.<\/p>\n<figure style=\"width: 309px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image9-9.png\" alt=\"Rows of organisms, with plants and animals at the bottom and humans, angels, and God at top.\" width=\"309\" height=\"449\" \/><figcaption class=\"wp-caption-text\">Figure 14.4: The Great Chain of Being from the Rhetorica Christiana by Fray Diego de Valades (1579). Credit: Great Chain of Being 2 by Didacus Valades (Diego Valades 1579) and photographed by Rhetorica Christiana (via Getty Research) is in the public domain.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">There is also the \u201cGreat Chain of Being,\u201d conceived by ancient Greek philosophers like Plato (427\u2012348 B.C.E.) and Aristotle (384\u2012322 B.C.E.). They played a key role in laying the foundations of empirical science, whereby observations of everything from animals to humans were noted with the aim of creating taxonomic categories. Aristotle describes the Great Chain of Being as a ladder along which all objects, plants, animals, humans, and celestial bodies can be mapped in an overall hierarchy (in the order of existential importance, with humans placed near the top, just beneath divine beings; see Figure 14.4). When he writes about humans, Aristotle expressed the belief that certain people are inherently (or genetically) more instinctive rulers, while others are more natural fits for the life of a worker or enslaved person. Based on research by biological anthropologists, we currently recognize that these early systems of classification and hierarchization are unhelpful in studying human biological variation. Both behavioral traits and physical traits are coded for by multiple genes each, and how we exhibit those traits based on our genetics can vary significantly even between individuals of the same population.<\/p>\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d during the Scientific Revolution<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The 1400s to 1600s saw the beginnings of the <strong>Scientific Revolution<\/strong> in Western societies, with thinkers like Nicholas Copernicus, Galileo Galilei, and Leonardo Da Vinci publishing some of their most important findings. While by no means the first or only scholars globally to use observation and experimentation to understand the world around them, early scientists living at the end of the medieval period in Europe increasingly employed more experimentation, quantification, and rational thought in their work. This is the main difference between the work of the ancient Egyptians, Romans, and Greeks and that of later scientists such as Isaac Newton and Carl Linnaeus in the 1600s and 1700s.<\/p>\n<figure style=\"width: 215px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image24-2.png\" alt=\"Historic painting of a man in 18th-century wig and garments.\" width=\"215\" height=\"259\" \/><figcaption class=\"wp-caption-text\">Figure 14.5: Carl Linnaeus. Credit: <a class=\"rId35\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Carl_von_Linn%C3%A9.png\">Carl von Linn\u00e9<\/a> by <a class=\"rId36\" href=\"https:\/\/en.wikipedia.org\/wiki\/en:Alexander_Roslin\">Alexander Roslin<\/a> (1718-1793) is in the <a class=\"rId37\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Linnaeus is the author of <em>Systema Naturae<\/em> (1758), in which he classified all plants and animals under the formalized naming system known as <strong>binomial nomenclature<\/strong> (Figure 14.5). This system is <strong>typological<\/strong>, in that organisms are placed into groups according to how they are similar or different to others under study. What was most anthropologically notable about Linnaeus\u2019s typological system was that he was one of the first to group humans with apes and monkeys, based on the anatomical similarities between humans and nonhuman primates. However, Linnaeus viewed the world in line with <strong>essentialism<\/strong>, a problematic concept that dictates that there are a unique set of characteristics that organisms of a specific kind <em>must<\/em> have and that would remove organisms from taxonomic categorizations if they lacked any of the required criteria.<\/p>\n<p>Linnaeus subdivided the human species into four varieties, with overtly racist categories based on skin color and \u201cinherent\u201d behaviors. Some European scientists during this period were not aware of their own biases skewing their interpretations of biological variation, while others deliberately worked to shape public perceptions of human variation in ways that established \u201c<strong>otherness<\/strong>\u201d and enforced European domination and the subordination of non-European people. The conclusions and claims at which they arrived, consciously or subconsciously, often fit the times they were living through\u2014the so-called <strong>Age of Discovery<\/strong>, when the superiority of European cultures over others was a pervasive idea throughout people\u2019s social and political lives. Although much of Eurasia was linked by spice- and silk-trading routes, the European colonial period between the 1400s and 1700s was marked by many new and unfortunately violent encounters overseas (Figure 14.6). When Europeans arrived by ship on the shores of continents that were already inhabited, it was their first meeting with the Indigenous peoples of the Americas and Australasia, who looked, spoke, and behaved differently from peoples with whom they were familiar. Building on the idea of species and \u201csubspecies,\u201d natural historians of this time invented the term <em>race<\/em>, from the French <em>rasse<\/em> meaning \u201clocal strain.\u201d<\/p>\n<figure style=\"width: 421px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image25-4.png\" alt=\"Spanish explorers with their military and religious gear surrounding indigenous people.\" width=\"421\" height=\"273\" \/><figcaption class=\"wp-caption-text\">Figure 14.6: A painting depicting the colonization of the Mississippi River environs by Spaniard Hernando DeSoto in 1541 (painted in 1853 by William H. Powell). Credit: <a class=\"rId39\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Discovery_of_the_Mississippi.jpg\">Discovery of the Mississippi<\/a> by <a class=\"rId40\" href=\"https:\/\/en.wikipedia.org\/wiki\/en:William_Henry_Powell\">William Henry Powell<\/a> (photograph courtesy of <a class=\"rId41\" href=\"https:\/\/en.wikipedia.org\/wiki\/Architect_of_the_Capitol\">Architect of the Capitol<\/a>) is in the <a class=\"rId42\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">Another scientist of the times, Johann Friedrich Blumenbach (1752\u20121840), classified humans into five races based on his observations of cranial form variation as well as skin color. He thus dubbed the \u201coriginal\u201d form of the human cranium the \u201cCaucasian\u201d form, with the idea that the ideal climate conditions for early humans would have been in the Caucasus region near the Caspian Sea. The key insight Blumenbach presented was that human variation in any particular trait should be more accurately viewed as falling along a gradation (Figure 14.7). While some of his theories were correct according to what we observe today with more knowledge in genetics, they erroneously believed that human \u201csubspecies\u201d were \u201cdegenerated\u201d or \u201ctransformed\u201d varieties of an ancestral Caucasian or European race. According to them, the Caucasian cranial dimensions were the least changed over human evolutionary time, while the other skull forms represented geographic variants of this \u201coriginal.\u201d As will be discussed in greater detail later in this chapter, we have genetic and craniometric evidence for sub-Saharan Africa being the origin of the human species instead (see Chapter 12 on the fossil record that places the origins of modern <em>Homo sapiens<\/em> in north and east Africa). Based on work that shows how most biological characteristics are coded for by nonassociated genes, it is not reasonable to draw links between individuals\u2019 personalities and their skull shapes.<\/p>\n<figure style=\"width: 686px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image7-10.png\" alt=\"Historic drawing of five skulls.\" width=\"686\" height=\"259\" \/><figcaption class=\"wp-caption-text\">Figure 14.7: Five skull drawings representing specimens for Blumenbach\u2019s \u201cMongolian,\u201d \u201cAmerican,\u201d \u201cCaucasian,\u201d \u201cMalayan,\u201d and \u201cAethiopian\u201d races. Credit: <a class=\"rId44\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Blumenbach's_five_races.JPG\">Blumenbach&#8217;s five races<\/a> by Johann Friedrich Blumenbach is in the <a class=\"rId45\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>. Original in the 1795 Treatise on &#8220;De generis humani varietate nativa,&#8221; unnumbered page at the end of the book titled &#8220;Tab II&#8221;.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d and the Dawn of Scientific Racism<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Between the 1800s and mid-1900s, and contrary to what you might expect, an increased use of scientific methods to justify racial schemes developed in scholarship. Differing from earlier views, which saw all humans as environmentally deviated from one \u201coriginal\u201d humankind, classification systems after 1800 became more <strong>polygenetic<\/strong> (viewing all people as having separate origins) rather than <strong>monogenetic<\/strong> (viewing all people as having a single origin). Instead of moving closer to our modern-day understandings of human variation, there was increased support for the notion that each race was created separately and with different attributes (intelligence, temperament, and appearance).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The 1800s were an important precursor to modern biological anthropology as we know it, given that this was when the scientific measurement of human physical features (anthropometry) truly became popularized. However, empirical studies in the 1800s pushed even further the idea that Europeans were culturally and biologically superior to others. While considered one of the pioneers of American \u201cphysical\u201d anthropology, Samuel George Morton (1799\u20121851) was a scholar who had a large role in perpetuating 1800s scientific racism. By measuring cranial size and shape, he calculated that \u201cCaucasians,\u201d on average, have greater cranial volumes than other groups, such as the Indigenous peoples of the Americas and peoples Morton referred to collectively as \u201cNegros.\u201d Today, we know that cranial size variation depends on such factors as Allen\u2019s and Bergmann\u2019s rules, which give a more likely explanation: in colder environments, it is advantageous for those living there to have larger and rounder heads because they conserve heat more effectively than more slender heads (Beals et al. 1984). The leading figures in craniometry during the 1800s instead were linked heavily with powerful individuals and wealthy sociopolitical institutions and financial bodies. Theories in support of hierarchical racial schemes using \u201cscientific\u201d bases certainly helped continue the exploitative and unethical trafficking and enslavement of Africans between the 1500s and 1800s.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Morton went on to write in his publication <em>Crania Americana<\/em> (1839) a number of views that fit with a concept called <strong>biological determinism<\/strong>. The idea behind biological determinism is that an association exists between people\u2019s physical characteristics and their behavior, intelligence, ability, values, and morals. If the idea is that some groups of people are essentially superior to others in cognitive ability and temperament, then it is easier to justify the unequal treatment of certain groups based on outward appearances. Another such problematic thinker was Paul Broca (1824\u20121880), after whom a region of the frontal lobe related to language use is named (Broca\u2019s area). Influenced by Morton, Broca likewise claimed that internal skull capacities could be linked with skin color and cognitive ability. He went on to justify the European colonization of other global territories by purporting it was noble for a biologically more \u201ccivilized\u201d population to improve the \u201chumanity\u201d of more \u201cbarbaric\u201d populations. Today, these theories of Morton, Broca, and others like them are known to have no scientific basis. If we could speak with them today, they would likely try to emphasize that their conclusions were based on empirical evidence and not <em>a priori<\/em> reasoning. However, we now can clearly see that their reasoning was biased and affected by prevailing societal views at the time.<\/p>\n<h3 class=\"import-Normal\"><strong>\u201cRace\u201d and the Beginnings of Physical Anthropology<\/strong><\/h3>\n<p class=\"import-Normal\">In the early 20th century, we saw a number of new figures coming into the science of human variation and shifting the theoretical focus within. Most notably, these included Ale\u0161 Hrdli\u010dka and Franz Boas.<\/p>\n<figure style=\"width: 430px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image19-4.jpg\" alt=\"Historic photo of a middle-aged person in suit and bowtie.\" width=\"430\" height=\"558\" \/><figcaption class=\"wp-caption-text\">Figure 14.8: Ale\u0161 Hrdli\u010dka (1869\u00ad\u20121943), a Czech anthropologist who founded the American Journal of Physical Anthropology. Credit: <a class=\"rId47\" href=\"https:\/\/siarchives.si.edu\/collections\/siris_sic_10822?back=%2Fcollections%2Fsearch%3Fquery%3Dczech%26online%3Dtrue%26page%3D1%26perpage%3D10%26sort%3Drelevancy%26view%3Dlist#\">(Ales Hrdlicka) SIA2009-4246<\/a> (1903) by an unknown photographer <a class=\"rId48\" href=\"https:\/\/www.si.edu\/termsofuse\">is used for educational and non-commercial purposes as outlined by the Smithsonian.<\/a>. [<a class=\"rId49\" href=\"https:\/\/www.si.edu\/\">Smithsonian Institution<\/a> Archives, Record Unit 9521, Box 1, T. Dale Stewart Oral History Interview; and Record Unit 9528, Box 1, Henry B. Collins Oral History Interview.]<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ale\u0161 Hrdli\u010dka (1869\u00ad\u20121943) was a Czech anthropologist who moved to the United States. In 1903, he established the physical anthropology section of the National Museum of Natural History (Figure 14.8). In 1918, he founded the <em>American Journal of Physical Anthropology<\/em>, which remains one of the foremost scientific journals disseminating bioanthropological research. As part of his work and the scope of the journal, he differentiated \u201c<strong>physical anthropology<\/strong>\u201d from other kinds of anthropology: he wrote that physical anthropology is \u201cthe study of racial anatomy, physiology, and pathology\u201d and \u201cthe study of man\u2019s variation\u201d (Hrdli\u010dka 1918). In some ways, although the scope and technological capabilities of biological anthropologists have changed significantly, Hrdli\u010dka established an area of inquiry that has continued and prospered for over a hundred years.<\/p>\n<p class=\"import-Normal\">Franz Boas (1858\u20121942) was a German American anthropologist who established the four-field anthropology system in the United States and founded the American Anthropological Association in 1902. He argued that the scientific method should be used in the study of human cultures and the comparative method for looking at human biology worldwide. One of Boas\u2019s significant contributions to biological anthropology was the study of skull dimensions with respect to race. After a long-term research project, he demonstrated how cranial form was highly dependent on cultural and environmental factors and that human behaviors were influenced primarily not by genes but by social learning. He wrote in one essay for the journal <em>Science<\/em>: \u201cWhile individuals differ, biological differences between races are small. There is no reason to believe that one race is by nature so much more intelligent, endowed with great willpower, or emotionally more stable than another, that the difference would materially influence its culture\u201d (Boas 1931:6). This conclusion directly contrasted with the theories of the past that relied on biological determinism. Biological anthropologists today have found evidence that corroborates Boas\u2019s explanations: societies do not exist on a hierarchy or gradation of \u201ccivilizedness\u201d but instead are shaped by the world around them, their demographic histories, and the interactions they have with other groups.<\/p>\n<figure style=\"width: 358px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image2-7.png\" alt=\"Black-and-white sketch of tree labeled \u201cEugenics.\u201d\" width=\"358\" height=\"275\" \/><figcaption class=\"wp-caption-text\">Figure 14.9: Logo of the Second International Exhibition of Eugenics, held in 1921. The text of the logo states: &#8220;Eugenics is the self-direction of human evolution. Like a tree, eugenics draws its materials from many sources and organizes them into an harmonious entity.&#8221; Credit: <a class=\"rId51\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Eugenics_congress_logo.png\">Eugenics congress logo<\/a> scanned from <a class=\"rId52\" href=\"https:\/\/en.wikipedia.org\/wiki\/Harry_H._Laughlin\">Harry H. Laughlin<\/a>, The Second International Exhibition of Eugenics held September 22 to October 22, 1921, is in the <a class=\"rId53\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The first half of the 1900s still involved some research that was essentialist and focused on proving racial determinism. Anthropologists like Francis Galton (1822\u20121911) and Earnest A. Hooton (1887\u20121954) created the field of <strong>eugenics<\/strong> as an attempt to formalize the social scientific study of \u201cfitness\u201d and \u201csuperiority\u201d among members of 19th-century Europe. As a way of \u201cdealing with\u201d criminals, diseased individuals, and \u201cuncivilized\u201d people, eugenicists recommended prohibiting parts of the population from being married or sterilizing these members of society so they could no longer procreate (Figure 14.9). They instead encouraged \u201creproduction in individual families with sound physiques, good mental endowments, and demonstrable social and economic capability\u201d (Hooton 1936). In the 1930s, Nazi Germany used this false idea of there being \u201cpure races\u201d to highly destructive effect. The need to be protected against admixture from \u201cunfit\u201d groups was their justification for their blatant racism and purging of citizens that fell under their subjective criteria.<\/p>\n<p class=\"import-Normal\">It should be noted that eugenicist ideas were popularly discussed and debated in many non-European contexts, as in the U.S., China, and South Africa, too. The Immigration Restriction Act of 1924 was passed in the United States, with the explicit aim of reducing the country\u2019s \u201cburden\u201d of people considered inferior by restricting immigration of eastern European Jews, Italians, Africans, Arabs, and Asians. In the early 1900s, Chinese scientists and politicians showed great interest in eugenic ideologies, which came to dictate decisions in law-making, family life, and the medical field. Noted American anthropologist Ruth Benedict wrote extensively on Japanese culture and society during and after World War II. Her essentialist portrayals of Japanese people were heavily cited in popular discourse at the time. In 1950s South Africa, interracial marriages and sexual relations were banned by law; antimiscegenation became one of the huge focuses of apartheid resistance activists in later years. We still see the continuation of eugenics-based logic today around the world\u2014in exclusionary immigration laws, cases of incarcerated prison inmates being forcibly sterilized, and the persistence of intelligence testing as a form of measuring people\u2019s \u201cfitness\u201d in a society.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Shortly after World War II and the Nazi Holocaust, the full extent of essentialist, eugenicist thinking became clear. Social constructions of race, and the notion that one can predict psychological or behavioral traits based on external appearance, had become unpopular both within and outside the discipline. It was up to those in the field of physical anthropology at the time to separate physical anthropology from race concepts that supported unscientific and socially damaging agendas. This does not mean that there are no physiological or behavioral differences between different members of the human species. However, going forward, a number of physical anthropologists saw human biological variation as more complicated than simple typologies could describe.<\/p>\n<h3 class=\"import-Normal\"><strong>\u201cThe New Physical Anthropology\u201d<\/strong><\/h3>\n<figure style=\"width: 219px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image14-6.png\" alt=\"Black-and-white photo of a person with short hair in a white shirt and tie.\" width=\"219\" height=\"291\" \/><figcaption class=\"wp-caption-text\">Figure 14.10: Theodosius Dobzhansky, an important scientist who formulated the 20th-century \u201cmodern synthesis\u201d reconciling Charles Darwin\u2019s theory of evolution and Gregor Mendel\u2019s ideas on heredity. Credit: <a class=\"rId55\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Dobzhansky_no_Brasil_em_1943.jpg\">Dobzhansky no Brasil em 1943<\/a> by unknown photographer via <a class=\"rId56\" href=\"https:\/\/www.flickr.com\/photos\/celycarmo\/\">Flickr user Cely Carmo<\/a> is in the <a class=\"rId57\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">After 1950, focus steered away from the concept of \u201crace\u201d as a unit of variation and toward understanding why variation exists in <strong>population<\/strong><strong>s<\/strong> from an evolutionary perspective. This was outlined by those pioneering the \u201cnew physical anthropology,\u201d such as Sherwood Washburn, Theodosius Dobzhansky (Figure 14.10), and Julian Huxley, who borrowed this approach from contemporary population geneticists. Whether using genetic or phenotypic markers as the units of study, \u201cgroups\u201d or \u201cclusters\u201d of humans differentiated by these became defined as populations that differ in the frequency of some gene or genes. Anthropologists consider what \u201cmakes\u201d a population\u2014a group of individuals potentially capable of or actually interbreeding due to shared geographic proximity, language, ethnicity, culture, and\/or values. Put another way, a population is a local interbreeding group with reduced gene flow between themselves and other groups of humans. Members of the same population may be expected to share many genetic traits (and, as a result, many phenotypic traits that may or may not be visible outwardly).<\/p>\n<figure style=\"width: 240px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image15-6.png\" alt=\"Black-and-white photo of smiling person in a suit and tie in front of a building.\" width=\"240\" height=\"300\" \/><figcaption class=\"wp-caption-text\">Figure 14.11: Julian Huxley (1942). Credit: <a class=\"rId59\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Julian_Huxley_1-2.jpg\">Julian Huxley 1-2<\/a> by unknown photographer is in the <a class=\"rId60\" href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">Thinking of humans in terms of populations was part of Julian Huxley\u2019s (1942) \u201cModern Synthesis\u201d\u2014so named because it helped to reconcile two fundamental principles about evolution that had not been made sense of together before (Figure 14.11). As discussed in Chapter 3, Gregor Mendel (1822\u20121884) was able to show that inheritance was mediated by discrete particles (or genes) and not blended in the offspring. However, it was difficult for some 19th-century scientists to accept this model of genetic inheritance at the time because much of biological variation appeared to be continuous and not particulate (take skin color or height as examples). In the 1930s, it was demonstrated that traits could be polygenic and that multiple alleles could be responsible for any one phenotypic trait, thus producing the continuous variation in traits such as eye color that we see today. Thus, Huxley\u2019s \u201cModern Synthesis\u201d outlines not only how human populations are capable of exchanging genes at the microevolutionary level but also how multiple alleles for one trait (polygenic exchanges) can cause gradual macroevolutionary changes.<\/p>\n<h2 class=\"import-Normal\">Human Variation in Biological Anthropology Today<\/h2>\n<h3 class=\"import-Normal\"><strong>Many Human Traits Are Nonconcordant<\/strong><\/h3>\n<p class=\"import-Normal\">In our studies of human (genetic) variation today, we understand most human traits to be nonconcordant (Figure 14.12). \u201c<strong>Nonconcordance<\/strong>\u201d is a term used to describe how biological traits vary independent of each other\u2014that is, they do not get inherited in a correlative manner with other genetically controlled traits. For example, if you knew an individual had genes that coded for tall height, you would not be able to predict if they are lighter-skinned or have red hair. This is different from earlier essentialist views of human variation: the idea that skin color could predict one\u2019s brain function or even \u201ctemperament\u201d and tendencies toward criminal behavior.<\/p>\n<figure style=\"width: 594px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image17-2-1.jpg\" alt=\"World map with human silhouettes scattered across the continents.\" width=\"594\" height=\"304\" \/><figcaption class=\"wp-caption-text\">Figure 14.12: Most human biological traits are non-concordant, meaning traits vary independently and each trait has its own pattern of distribution around the world. In this image, different colors and patterns represent trait varieties. For example, the color and pattern of the head may represent hair color (dark to light), but sharing dark hair with another person does not mean you will share other traits (e.g. ability to digest lactose or ABO blood type). Credit: Nonconcordance original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Katie Nelson is under a <a class=\"rId62\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Human Variation Is Clinal\/Continuous (Not Discrete)<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Frank B. Livingstone (1928\u20122005) wrote: \u201cThere are no races, only clines\u201d (1962: 279). A <strong>cline<\/strong> is a gradation in the frequency of an allele\/trait between populations living in different geographic regions. Human variation cannot be broken into discrete \u201craces,\u201d because most physical traits vary on a continuous or \u201cclinal\u201d basis. One obvious example of this is how human height does not only come in three values (\u201cshort,\u201d \u201cmedium,\u201d and \u201ctall\u201d) but instead varies across a spectrum of vertical heights achievable by humans all over the world. On the one hand, we can describe human height as exhibiting <strong>continuous <\/strong><strong>variation<\/strong>, forming a continuous pattern, but height does not vary according to where people live across the globe and does not exhibit a clinal pattern. On the other hand, skin color variation between populations does show patterning that fits quite well on to how near or far they are from each other on a world map. This makes a trait like skin color clinally distributed worldwide. When large numbers of genetic loci for large numbers of samples were sampled from human populations distributed worldwide during the 1960s and 1970s, the view that certain facets of human diversity were clinally distributed was further supported by genetic data.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To study human traits that are clinally distributed, genetic tests must be performed to uncover the true frequencies of an allele or trait across a certain geographic space. One easily visible example of a clinal distribution seen worldwide is the patterning of human variation in skin color. Whether in southern Asia, sub-Saharan Africa, or Australia, dark brown skin is found. Paler skin tones are found in higher-latitude populations such as those who have lived in areas like Europe, Siberia, and Alaska for millennia. Skin color is easily observable as a phenotypic trait exhibiting continuous variation.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">A clinal distribution still derives from genetic inheritance; however, clines often correspond to some gradually changing environmental factor. Clinal patterns arise when selective pressures in one geographic area differ from those in another as well as when people procreate and pass on genes together with their most immediate neighbors. There are several mechanisms, selective and neutral, that can lead to the clinal distribution of an allele or a biological trait. <strong>Natural selection<\/strong> is the mechanism that produced a global cline of skin color, whereby darker skin color protects equatorial populations from high amounts of UV radiation; there is a transition of lessening pigmentation in individuals that reside further and further away from the tropics (Jablonski 2004; Jablonski and Chaplin 2000; see Figure 14.13). The ability and inability to digest lactose (milk sugar) among different world communities varies according to differential practices and histories of milk and dairy-product consumption (Gerbault et al. 2011; Ingram et al. 2009). Where malaria seems to be most prevalent as a disease stressor on human populations, a clinal gradient of increasing sickle cell anemia experience toward these regions has been studied extensively by genetic anthropologists (Luzzatto 2012). Sometimes, culturally defined mate selection based on some observable trait can lead to clinal variation between populations as well.<\/p>\n<figure style=\"width: 676px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image22-6.png\" alt=\"A global map shaded representing skin colors.\" width=\"676\" height=\"370\" \/><figcaption class=\"wp-caption-text\">Figure 14.13: A global map of skin colors shows that dark skin pigmentation is more common in areas that receive more UV radiation (near the equator and in high altitude areas). Light skin is more common at northern and southern latitudes. It is worth bearing in mind, though, that these do not tell the full story of how human skin pigmentation varies worldwide. Each region will contain populations that exhibit a range of skin tones. In this way, this map is not perfect as an illustration of skin-color distribution. Credit: Mercator style projection map showing human skin color according to Biasutti 1940.png by Dark Tichondrias at English Wikipedia, modified (cropped) by Tuvalkin, is under a CC BY-SA 4.0 License.<\/figcaption><\/figure>\n<p class=\"import-Normal\">Two neutral microevolutionary processes that may produce a cline in a human allele or trait are <strong>gene flow<\/strong> and <strong>genetic drift <\/strong>(see Chapter 4). The ways in which neutral processes can produce clinal distributions is seen clearly when looking at clinal maps for different blood groups in the human ABO blood group system (Figure 14.14). For instance, scientists have identified an East-to-West cline in the distribution of the blood type <em>B<\/em> allele across Eurasia. The frequency of <em>B<\/em> allele carriers decreases gradually westward when we compare the blood groups of East and Southeast Asian populations with those in Europe. This shows how populations residing nearer to one another are more likely to interbreed and share genetic material (i.e., undergo gene flow). We also see 90%\u2012100% of native South American individuals, as well as between 70%\u201290% of Aboriginal Australian groups, carrying the <em>O<\/em> allele (Mourant, \u200b\u200bKope\u0107, and Domaniewska-Sobczak 1976). These high frequencies are likely due to random genetic drift and founder effects, in which population sizes were severely reduced by the earliest <em>O<\/em> allele-carrying individuals migrating into those areas. Over time, the <em>O<\/em> blood type has remained predominant.<\/p>\n<p class=\"import-Normal\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image8.gif\" alt=\"World map showing varying frequencies of blood type A.\" width=\"516\" height=\"284\" \/><\/p>\n<p class=\"import-Normal\"><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image5.gif\" alt=\"World map shows the highest frequencies of blood type B in parts of Asia.\" width=\"518\" height=\"283\" \/><\/p>\n<figure style=\"width: 516px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image13.gif\" alt=\"World map shows the highest frequencies of blood type O.\" width=\"516\" height=\"284\" \/><figcaption class=\"wp-caption-text\">Figure 14.14a\u2013c: a. Global distribution of blood type A. b. Global distribution of blood type B. c. Global distribution of blood type O. <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\" target=\"_blank\" rel=\"noopener\">A text description of this image is available<\/a>. Credit: a. <a class=\"rId69\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Map_of_blood_group_a.gif\">Map of blood group a<\/a> by <a class=\"rId70\" href=\"https:\/\/en.wikipedia.org\/wiki\/User:Muntuwandi\">Muntuwandi<\/a> at <a class=\"rId71\" href=\"https:\/\/en.wikipedia.org\/\">en.wikipedia<\/a> is under a <a class=\"rId72\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>. b. <a class=\"rId73\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Map_of_blood_group_b.gif\">Map of blood group b<\/a> by <a class=\"rId74\" href=\"https:\/\/en.wikipedia.org\/wiki\/User:Muntuwandi\">Muntuwandi<\/a> at <a class=\"rId75\" href=\"https:\/\/en.wikipedia.org\/\">en.wikipedia<\/a> is under a <a class=\"rId76\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>. c. <a class=\"rId77\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Map_of_blood_group_o.gif\">Map of blood group o<\/a> is based on diagrams from <a class=\"rId78\" href=\"https:\/\/anthro.palomar.edu\/vary\/vary_3.htm\">https:\/\/anthro.palomar.edu\/vary\/vary_3.htm<\/a>, reproduced from A. E. Mourant et al. (1976), and is under a <a class=\"rId79\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Genetic Variation Is Greater Within Group than Between Groups<\/strong><\/h3>\n<figure style=\"width: 295px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image27-2.jpg\" alt=\"Two medium-sized circles labeled Asian and European largely overlap. A larger circle labeled African surrounds both.\" width=\"295\" height=\"274\" \/><figcaption class=\"wp-caption-text\">Figure 14.15: Circles represent human genetic variation. Most variants are shared among individuals on all continents. There are more variants in Africa, some of which are not found in Europe or Asia. Credit: Human Genetic Variation original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Katie Nelson is under a <a class=\"rId81\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p>One problem with race-based classifications is they relied on an erroneous idea that individuals with particular characteristics would share more similar genes with each other within a particular \u201crace\u201d and share less with individuals of other \u201craces\u201d possessing different traits and genetic makeups. However, since around 50 years ago, scientific studies have shown that the majority of human genetic differences worldwide exist <em>within<\/em> groups (or \u201craces\u201d) individually rather than <em>between<\/em> groups. Indeed, most genetic variation we see occurs in Africa, and many variants are shared among individuals on all continents (Figure 14.15).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">In 2002, a landmark article by Noah Rosenberg and colleagues explored worldwide human genetic variation using an even-greater genetic data set. They used 377 highly variable markers in the human genome and sampled from 1,056 individuals representative of 52 populations. The markers chosen for study were not ones that code for any expressed genes. Because these regions of the human genome were made of unexpressed genes, we may understand these markers as neutrally derived (as opposed to selectively derived) because they do not code for functional advantages or disadvantages. These neutral genetic markers likely reflect an intricate combination of regional founder effects and population histories. Analyses of these neutral markers allowed scientists to identify that 93%\u201295% of global genetic differences, referred to as <strong>variance<\/strong>, can be accounted for by within-population differences, while only a small proportion of genetic variance (3%\u20125%) can be attributed to differences among major groups (Rosenberg et al. 2002). This research supports the theory that distinct biological races do not exist, even though misguided concepts of race may still have real social and political consequences.<\/p>\n<h3 class=\"import-Normal\"><strong>Biological Data Fit Isolation-By-Distance and Out-of-Africa Models<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">One further note is that the world\u2019s population may be genetically divided into \u201cgroups,\u201d \u201csubsets,\u201d \u201cclumps,\u201d or \u201cclusters\u201d that reflect some degree of genetic similarity. These identifiable clusters reflect genetic or geographic distances\u2014either with gene flow facilitated by proximity between populations or impeded by obstacles like oceans or environmentally challenging habitats (Rosenberg et al. 2005). Sometimes, inferred clusters using multiple genetic loci are interpreted by nongeneticists literally as \u201cancestral populations.\u201d However, it would be wrong to assume from these genetic results that highly differentiated and \u201cpure\u201d ancestral groups ever existed. These groupings reflect differences that have arisen over time due to clinal patterning, genetic drift, and\/or restricted or unrestricted gene flow (Weiss and Long 2009). The clusters identified by scientists are arbitrary and the parameters used to split up the global population into groups is subjective and dependent on the particular questions or distinctions being brought into focus (Relethford 2009).<\/p>\n<figure style=\"width: 341px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image6-7.png\" alt=\"Map of the continent of Africa with the lower two-thirds shaded.\" width=\"341\" height=\"341\" \/><figcaption class=\"wp-caption-text\">Figure 14.16: Sub-Saharan Africa (shaded dark\/green). Credit: <a class=\"rId83\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Sub-Saharan-Africa.png\">Sub-Saharan Africa<\/a> by <a class=\"rId84\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Ezeu\">Ezeu<\/a> has been designated to the <a class=\"rId85\" href=\"https:\/\/creativecommons.org\/share-your-work\/public-domain\/cc0\/\">public domain (CC0)<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Additionally, research on worldwide genetic variation has shown that human variation decreases with increasing distance from sub-Saharan Africa, where there is evidence for this vast region being the geographical origin of anatomically modern humans (Liu et al. 2006; Prugnolle, Manica, and Balloux 2005; see Figures 14.16 and 14.17). Genetic differentiation decreases in human groups the further you sample data from relative to sub-Saharan Africa because of serial founder effects (Relethford 2004). Over the course of human colonization of the rest of the world outside Africa, populations broke away in expanding waves across continents into western Asia, then Europe and eastern Asia, followed by Oceania and the Americas. As a result, founder events occurred whereby genetic variation was lost, as the colonization of each new geographical region involved a smaller number of individuals moving from the original larger population to establish a new one (Relethford 2004). The most genetic variation is found across populations residing in different parts of sub-Saharan Africa, while other current populations in places like northern Europe and the southern tip of South America exhibit some of the least genetic differentiation relative to all global populations (Campbell and Tishkoff 2008).<\/p>\n<figure style=\"width: 469px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image3-6.png\" alt=\"Two scatterplots.\" width=\"469\" height=\"516\" \/><figcaption class=\"wp-caption-text\">Figure 14.17: Comparison of the genetic distance and geographical distance between populations. In the top graph, the pattern reveals that genetic variation conforms to an Out-of-Africa model, as those populations further away from Addis Ababa in Ethiopia share a smaller number of alleles; in the bottom graph, we see the populations follow an isolation-by-distance model, as pairs of populations further apart geographically seem to have greater genetic distance (Kanitz et al. 2018). Credit: <a class=\"rId87\" href=\"https:\/\/journals.plos.org\/plosone\/article?id=10.1371\/journal.pone.0192460\">Complex genetic patterns (figure 1)<\/a> by Kanitz et al. (2018) is under a <a class=\"rId88\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY 4.0 License<\/a>.<\/figcaption><\/figure>\n<\/div>\n<div class=\"__UNKNOWN__\">\n<figure style=\"width: 377px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image1-9.png\" alt=\"Two large circles connected by a small area.\" width=\"377\" height=\"309\" \/><figcaption class=\"wp-caption-text\">Figure 14.18: The founder effect is a change in a small population\u2019s gene pool due to a limited number of individuals breaking away from a parent population. Credit: <a class=\"rId90\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Bottleneck_effect.jpg\">Bottleneck effect<\/a> by <a class=\"rId91\" href=\"https:\/\/wikieducator.org\/User:Tsaneda\">Tsaneda<\/a> is under a <a class=\"rId92\" href=\"https:\/\/creativecommons.org\/licenses\/by\/3.0\/legalcode\">CC BY 3.0 License<\/a>.<\/figcaption><\/figure>\n<p>Besides fitting nicely into the <strong>Out-of-Africa model<\/strong>, worldwide human genetic variation conforms to an <strong>isolation-by-distance model<\/strong>, which predicts that genetic similarity between groups will decrease exponentially as the geographic distance between them increases (Kanitz et al. 2018). This is because of the greater and greater restrictions to gene flow presented by geographic distance, as well as cultural and linguistic differences that occur as a result of certain degrees of isolation. Since genetic data conform to isolation-by-distance and Out-of-Africa models, these findings support the abolishment of \u201crace\u201d groupings. This research demonstrates that human variation is continuous and cannot be differentiated into geographically discrete categories. There are no \u201cinherent\u201d or \u201cinnate\u201d differences between human groups; instead, variation derives from some degree of natural selection, as well as neutral processes like <strong>population bottle-necking<\/strong> (Figure 14.18), random <strong>mutations<\/strong> in the DNA, genetic drift, and gene flow through between-mate interbreeding.<\/p>\n<h3 class=\"import-Normal\"><strong>Humans Have Higher Homogeneity Compared to Many Other Species<\/strong><\/h3>\n<p class=\"import-Normal\">An important fact to bear in mind is that humans are 99.9% identical to one another. This means that the apportionments of human variation discussed above only concern that tiny 0.1% of difference that exists between all humans globally. Compared to other mammalian species, including the other great apes, human variation is remarkably lower. This may be surprising given that the worldwide human population has already exceeded seven billion, and, at least on the surface level, we appear to be quite phenotypically diverse. Molecular approaches to human and primate genetics tells us that external differences are merely superficial. For a proper appreciation of human variation, we have to look at our closest relatives in the primate order and mammalian class. Compared to chimpanzees, bonobos, gorillas and other primates, humans have remarkably low average genome-wide <strong>heterogeneity<\/strong> (Osada 2005).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">When we look at chimpanzee genetic variation, it is fascinating that western, central, eastern, and Cameroonian chimpanzee groups have substantially more genetic variation between them than large global samples of human DNA (Bowden et al. 2012; Figure 14.19). This is surprising given that all of these chimpanzee groups live relatively near one another in Africa, while measurements of human genetic variation have been conducted using samples from entirely different continents. First, geneticists suppose that this could reflect differential experiences of the founder effect between humans and chimpanzees. As it has been argued that all non-African human populations descended from a small number of anatomically modern humans who left Africa, it would be expected that all groups descended from that smaller ancestral group would be similar genetically. Second, our species is really young, given that we have only existed on the planet for around 150,000 to 300,000 years. This gave humans little time for random genetic mutations to occur as genes get passed down through genetic interbreeding and meiosis. Chimpanzees, however, have inhabited different <strong>ecological niches<\/strong>, and less interbreeding has occurred between the four chimpanzee groups over the past six to eight million years compared to the amount of gene flow that occurred between worldwide human populations (Bowden et al. 2012).<\/p>\n<figure style=\"width: 648px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image16-7.png\" alt=\"Map of Africa showing the ranges of chimpanzees from west to east.\" width=\"648\" height=\"339\" \/><figcaption class=\"wp-caption-text\">Figure 14.19: Distribution of the genus Pan, including bonobos and the four subspecies of chimpanzee, across western and central Africa (Clee et al. 2015). <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\" target=\"_blank\" rel=\"noopener\">A text description of this image is available<\/a>. Credit: <a class=\"rId94\" href=\"https:\/\/bmcecolevol.biomedcentral.com\/articles\/10.1186\/s12862-014-0275-z\">Chimpanzee subspecies ranges (Figure 1)<\/a> by Clee et al. 2015 is under a <a class=\"rId95\" href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Recent advances have now enabled the attainment of genetic samples from the larger family of great apes and the evaluation of genetic variation among bonobos, orangutans, and gorillas alongside that of chimpanzees and humans (Prado-Martinez et al. 2013). Collecting such data and analyzing primate genetic variation has been important not only to elucidate how different ecological, demographic, and climatic factors have shaped our evolution but also to inform upon conservation efforts and medical research. Genes that may code for genetic susceptibilities to tropical diseases that affect multiple primates can be studied through genome-wide methods. Species differences in the genomes associated with speech, behavior, and cognition could tell us more about how human individuals may be affected by genetically derived neurological or speech-related disorders and conditions (Prado-Martinez et al. 2013; Staes et al. 2017). In 2018, a great ape genomic study also reported genetic differences between chimpanzees and humans related to brain cell divisions (Kronenberg et al. 2018). From these results, it may be inferred that cognitive or behavioral variation between humans and the great apes might relate to an increased number of cortical neurons being formed during human brain development (Kronenberg et al. 2018). Comparative studies of human and nonhuman great ape genetic variation highlight the complex interactions of population histories, environmental changes, and natural selection between and within species. When viewed in the context of overall great ape variation, we may reconsider how variable the human species is relatively and how unjustified previous \u201crace\u201d concepts really were.<\/p>\n<h3 class=\"import-Normal\"><strong>Phenotypic Traits That Reflect Neutral Evolution<\/strong><\/h3>\n<p class=\"import-Normal\">Depending on the trait being observed, different patterns of phenotypic variation may be found within and among groups worldwide. In this subsection, some phenotypic traits that reflect the aforementioned patterns of genetic variation will be discussed.<\/p>\n<figure style=\"width: 301px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image18-4.jpg\" alt=\"Illustration of one anthropologist studying teeth, and another looking into a microscope.\" width=\"301\" height=\"301\" \/><figcaption class=\"wp-caption-text\">Figure 14.20: Contemporary anthropologists who use many types of skeletal markers have demonstrated that a majority of cranial variation occurs within populations rather than between populations and that there is a decrease in variation with distance from Africa. Credit: <a class=\"rId97\" href=\"https:\/\/img1.wsimg.com\/isteam\/ip\/0f6c1c17-41ea-4caf-b839-73c676d69f01\/DentalHeartNecklace.jpg\/:\/rs=w:1280,h:1280\">Dental Anthropologist Heart Necklace<\/a> by <a class=\"rId98\" href=\"https:\/\/anthroillustrated.com\/\">Anthro Illustrated<\/a> is under a <a class=\"rId99\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Looking beyond genetic variation briefly, recent studies have revisited biological anthropology\u2019s earlier themes of externally observable traits, such as skull shape. In the last 20 or so years, anthropologists have evaluated the level to which human cranial shape variation reflects the results from genetic markers, such as those used previously to fit against Out-of-Africa models (Relethford 2004) or those used in the apportionment of human variation between and within groups (Lewontin 1972; Rosenberg et al. 2002). Using larger sample sizes of cranial data collected from thousands of skulls worldwide and a long list of cranial measurements, studies demonstrate a similar decrease in variation with distance from Africa and show that a majority of cranial variation occurs within populations rather than between populations (Betti et al. 2009; Betti et al. 2010; Manica et al. 2007; Relethford 2001; von Cramon-Taubadel and Lycett 2008; see Figure 14.20). The greatest cranial variation is found among skulls of sub-Saharan African origin, while the least variation is found among populations inhabiting places like Tierra del Fuego at the southern tip of Argentina and Chile. While ancient and historical thinkers previously thought \u201crace\u201d categories could reasonably be determined based on skull dimensions, modern-day analyses using more informative sets of cranial traits simply show that migrations out of Africa and the relative distances between populations can explain a majority of worldwide cranial variation (Betti et al. 2009).<\/p>\n<figure style=\"width: 250px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image21-6.png\" alt=\"Sketch of bone with bony loops at the top and coil at the bottom.\" width=\"250\" height=\"208\" \/><figcaption class=\"wp-caption-text\">Figure 14.21: Diagram of the bony labyrinth in the inner ear. Credit: <a class=\"rId101\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Bony_labyrinth.png\">Bony labyrinth<\/a> by <a class=\"rId102\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Selket\">Selket<\/a> has been designated to the <a class=\"rId103\" href=\"https:\/\/creativecommons.org\/share-your-work\/public-domain\/cc0\/\">public domain (CC0)<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">This same patterning in phenotypic variation has even been found in studies examining shape variation of the pelvis (Betti et al. 2013; Betti et al. 2014), the teeth (Rathmann et al. 2017), and the human <strong>bony labyrinth<\/strong> of the ear (Ponce de Le\u00f3n et al. 2018;Figure 14.21). The skeletal morphology of these bones still varies worldwide, but a greater proportion of that variation can still be attributed to the ways in which human populations migrated across the world and exchanged genes with those closer to them rather than those further away. Human skeletal variation in these parts of the body is continuous and nondiscrete. Given the important functions of the cranium and these other skeletal parts, we may infer that the genes that underpin their development have been relatively conserved by neutral evolutionary processes such as genetic drift and gene flow. It is also important to note that while some traits such as height, weight, cranial dimensions, and body composition are determined, in part, by genes, the underlying developmental processes behind these traits are underpinned by complex polygenic mechanisms that have led to the continuous spectrum of variation in such variables among modern-day human populations.<\/p>\n<h3 class=\"import-Normal\"><strong>Phenotypic Traits That Reflect Natural Selection<\/strong><\/h3>\n<p class=\"import-Normal\">Even though 99.9% of our DNA is the same across all humans worldwide, and many traits reflect neutral processes, there are parts of that remaining 0.1% of the human genome that code for individual and regional differences. Similarly to craniometric analyses that have been conducted in recent decades, human variation in skin color has also been reassessed using new methods and in light of greater knowledge of biological evolution.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">New technologies allow scientists to use color photometry to sample and quantify the visible wavelength of skin color, in a way 19th- and 20th-century readers could not. In one report, it was found that 87.9% of global skin color variation can be attributed to genetic differences <em>between<\/em> groups, 3.2% to those among local populations within regions, and 8.9% <em>within<\/em> local populations (Relethford 2002). This apportionment differs significantly and is the reverse situation found in the distribution of genetic differences we see when we examine genetic markers such as blood type\u2013related alleles. However, this pattern of human skin color worldwide is not surprising, given that we now understand that past selection has occurred for darker skin near the equator and lighter skin at higher latitudes (Jablonski 2004; Jablonski and Chaplin 2000). While most genetic variation reflects neutral variation due to population migrations, geographic isolation, and restricted gene flow dynamics, some human genetic\/phenotypic variation is best explained as local adaptation to environmental conditions (i.e., selection). Given that skin color variation is atypical compared to other genetic markers and biological traits, this, in fact, goes against earlier \u201crace\u201d typologies. This is because recent studies ironically show how so much of genetic variation relates to neutral processes, while skin color does not. It follows that skin color <em>cannot<\/em> be viewed as useful in making inferences about other human traits.<\/p>\n<figure style=\"width: 580px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image23-3.jpg\" alt=\"Person standing at podium in front of a screen with arms partly raised.\" width=\"580\" height=\"384\" \/><figcaption class=\"wp-caption-text\">Figure 14.22: Genomicists and biological anthropologists have dedicated efforts to improving quantitative methods of measuring hair and skin variation over the last twenty years. Dr. Nina Jablonski is one such biological anthropologist specializing in the evolution and variation of human skin pigmentation. Credit: <a class=\"rId105\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Nina_Jablonski_2016_The_Skin_of_Homo_sapiens_01_%28cropped%29.jpg\">Nina Jablonski 2016 The Skin of Homo sapiens 01 (cropped)<\/a> by <a class=\"rId106\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Ptolusque\">Ptolusque<\/a> is under a <a class=\"rId107\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\">CC BY-SA 4.0 license<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">It is also true that some populations have not been studied extensively in skin pigmentation genetics (e.g., African, Austronesian, Melanesian, Southeast Asian, Indigenous American, and Pacific Islander populations, according to Lasisi and Shriver 2018). Earlier dispersals of these populations, and their local genetic varition, will have contributed to worldwide genetic variation, inclusive of skin pigmentation variation. Gene loci we did not previously appreciate as being linked to pigmentation are now being recognized thanks to better tools, more diverse genetic samples, and more accessible datasets (Quillen et al. 2018). Biological anthropologists look forward to further discoveries elucidating the different selective pressures and population dynamics that influence skin pigmentation evolution.<\/p>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Social Implications<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To finish this chapter, we will consider the social, economic, political, and biological implications of poor understandings of race and the deliberate perpetuation of social and medical racism.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The Black Lives Matter movement (BLM) of 2013 began with the work of racial justice activists and community organizers Alicia Garza, Opal Tometi, and Patrissa Cullors. First incited by the murder of Trayvon Martin, a 17-year-old African American, and the acquittal of the man who shot him, BLM went on to protest against the deaths of numerous Black individuals, most of whom were killed by police officers (for example, Ahmaud Arbery was killed in February of 2020 by two white non-police officers). Some key characteristics of BLM from the start were its decentralized grassroots structure, the role of university students and social media in spreading awareness of the movement, and its embrace of other movements (e.g., climate justice, ending police brutality, feminist campaigns, queer activism, immigration reform, etc.). When George Floyd was murdered by a white police officer on May 25, 2020, the BLM gained new momentum, across 2,000-plus cities in the United States, and among many protesting against historic racism and police brutality in other contexts around the globe. Many in the biological anthropology community have responded to these events with a great dedication to working against systemic racism in society and institutions (American Association of Biological Anthropologists 2020).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">BLM continues to be an important movement, as is evidenced in the degree of community organizing, mutual aid efforts, calls for political reform, progress toward curriculum reform and equality, inclusion and diversity (EDI) work in businesses and universities, the removal of monuments honoring historical figures associated with slavery and racism, and many other important actions. Garza (2016) writes: \u201cThe reality is that race in the United States operates on a spectrum from black to white \u2026 the closer you are to white on that spectrum, the better off you are.\u201d Tometi (2016) has stated: \u201cWe need [a human rights movement that challenges systemic racism] because the global reality is that Black people are subject to all sorts of disparities in most of our challenging issues of our day. I think about climate change, and how six of the ten worst impacted nations by climate change are actually on the continent of Africa.\u201d In the words of Cullors (2016), \u201cBlack Lives Matter is our call to action. It is a tool to reimagine a world where Black people are free to exist, free to live. It is a tool for our allies to show up differently for us.\u201d We gather from their words the importance of learning from the egregious role that anthropologists have played in the past, recognizing the legacies of \u201cscientific\u201d justifications for eugenics and racism in our society today, and proactively working toward environmental and social equity.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Another major industry that engages in the quantification and interpretation of human variation is medical and clinical work (National Research Council [U.S.] Committee on Human Genome Diversity 1997). Large-scale genomic studies sampling from human populations distributed worldwide have produced detailed knowledge on variation in disease resistance or susceptibility between and within populations. Let\u2019s think about drug companies who develop medicines for Black patients particularly. The predispositions to particular diseases are higher among people of African descent than some pharmaceutical businesses have taken into account. Through targeted sampling of various world groups, clinical geneticists may also identify genetic risk factors of certain common disorders such as chronic heart disease, asthma, diabetes, autoimmune diseases, and behavioral disorders. Having an understanding of population-specific biology is crucial in the development of therapies, medicines, and vaccinations, as not all treatments may be suitable for every human, depending on their genotype. During diagnosis and treatment, it is important to have an evolutionary perspective on gene-environment relationships in patients. Typological concepts of \u201crace\u201d are not useful, given that most racial groups (whether self-identified or not) popularly recognized lack homogeneity and are, in fact, variable. <strong>Cystic fibrosis<\/strong>, for instance, occurs in all world populations but can often be underdiagnosed in populations with African ancestry because it is thought of as a \u201cwhite\u201d disease (Yudell et al. 2016).<\/p>\n<p class=\"import-Normal\">Sociologists, law scholars, and professors of race studies have written extensively on how genetic\/technological\/medical revolutions impact people of color. In her book, <em>Fatal Invention: How Science, Politics, and Big Business Re-create Race in the Twenty-First Century <\/em>(2013), Professor Dorothy E. Roberts writes about how technological advances have been used in resuscitating race as a biological category for dividing humans in essentialist ways (Figure 14.23). She notes how members of law enforcement have engaged in racial profiling, sometimes with the use of machine-learning and facial-recognition technologies. Ancestry-testing services also purport to tell us \u201cwhat\u201d we are and to insist that this information is \u201cwritten\u201d in our genes. Such advertising campaigns obscure the nuances of genetic variation with the primary motive of tapping into people\u2019s desire to \u201cknow themselves\u201d and driving up profits for their businesses. Commercial genetic testing reinforces the idea that genes map neatly onto race, all while generating massive stores of data in DNA databases. In Roberts\u2019s view, the myth of the biological concept of race being perpetuated in these ways undermines a just society and reproduces racial inequalities.<\/p>\n<figure style=\"width: 593px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image12-6.png\" alt=\"Book cover with two DNA strands and next to the smiling portrait of the author.\" width=\"593\" height=\"305\" \/><figcaption class=\"wp-caption-text\">Figure 14.23: Professor Dorothy E. Roberts is a sociologist, legal scholar, and expert on the relationships among technology, medicine, bioethics, policymaking, race, and racism. Credit: <a class=\"rId109\" href=\"https:\/\/kpfa.org\/episode\/talkies-august-23-2016\/\">Dorothy Roberts author of Fatal Invention<\/a> by <a class=\"rId110\" href=\"https:\/\/kpfa.org\/\">https:\/\/kpfa.org\/<\/a> is copyrighted and used with permission.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">The COVID-19 pandemic has had a significant impact on the world\u2019s population, particularly people living in the economic Global South and many Black, Indigenous and communities of color residing in the Global North. We have witnessed disproportionately high numbers of COVID-related deaths and infection cases among marginalized groups. Many immigrants and ethnic minorities in various societies have also experienced scapegoating and blame directed at them for being the source of COVID-19 spread.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To inform us on how to interpret this current worldwide pandemic, historians and anthropologists are looking back at the lessons learned from past instances of racist medicine (discriminatory practices based on broader social discrimination) and medical racism (application of discriminatory practices justified on medical grounds). Historically, who could become doctors and medical professionals was often racialized, gendered, and class specific. This made it difficult for many to overcome prejudices against women, Black people, Indigenous individuals, or other people of color from becoming doctors and clinical researchers in places such as South Africa and the United States. This, in turn, affects the sorts of information we know about health levels and health outcomes among these very groups. In the past decade, long-overdue attention is finally being paid to how race affects biological outcomes. For instance, researchers have focused on the negative legacies of racial discrimination and racism-induced stress on hormone (im)balances, mental health disorders, cardiovascular disease prevalence, and other health outcomes (Kuzawa and Sweet 2009; Shonkoff, Slopen, and WIlliams 2021; Williams 2018). The technology and standards of protocol in medical testing have been scrutinized (for more on how pulse oximeters were not designed with nonwhite patients in mind, for example, see Sjoding et al. 2020). Scholars of race and medicine have also written on how illness and disease spread have often been used to perpetuate societal prejudices. This manifests as xenophobic tendencies at a societal level, such as the blaming of \u201coutgroups\u201d and increased \u201cin-group\u201d protectiveness. Overreliance on the idea that people are \u201cinherently\u201d disease carriers due to genetic or biological reasons leads to improper accounting for socioeconomic or infrastructural issues that lead to differential disease prevalence amongst minority communities. (For more on race and COVID, see Tsai 2021 as well as this textbook\u2019s Chapter 16: Contemporary Topics: Human Biology and Health.)<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">It is important to remember that while it is possible to look for clues about one\u2019s ancestry or geographic origin based on skull morphology, again, the amount of distinctiveness in any given sample makes it impossible to distinguish whether a cranium belongs to one group (Relethford 2009). Individuals can vary in their skeletal dimensions by continental origin, country origin, regional origin, sex, age, environmental factors, and the time period in which they lived, making it difficult to assign individuals to particular categories in a completely meaningful way (Ousley, Jantz, and Freid 2009). When forensic reports and scientific journal articles give an estimation of ancestry, it is crucial to keep in mind that responsible assignments of ancestry will be done through robust statistical testing and stated as a probability estimate. Today, we also live in a more globalized world where a skeletal individual may have been born originally to parents of two separate traditional racial categories. In contexts of great heterogeneity within populations, this definitely adds difficulty to the work of forensic scientists and anthropologists preparing results for the courtroom (genetic testing may be comparatively more helpful in such situations).<\/p>\n<\/div>\n<div class=\"textbox\">\n<h2 class=\"import-Normal\">Dig Deeper: Measuring F<sub>ST<\/sub><\/h2>\n<p class=\"import-Normal\">Richard Lewontin (1929\u2012) is a biologist and evolutionary geneticist who authored an article evaluating where the total genetic variation in humans lies. Titled \u201cThe Apportionment of Human Diversity\u201d (Lewontin 1972), the article addressed the following question: On average, how genetically similar are two randomly chosen people from the same group when compared to two randomly chosen people from different groups?<\/p>\n<p class=\"import-Normal\">Lewontin studied this problem by using genetic data. He obtained data for a large number of different human populations worldwide using 17 genetic markers (including alleles that code for various important enzymes and proteins, such as blood-group proteins). The statistical analysis he ran used a measure of human genetic differences in and among populations known as the fixation index (F<sub>ST<\/sub>).<\/p>\n<p class=\"import-Normal\">Technically, F<sub>ST<\/sub> can be defined as the proportion of total genetic variance within a <em>subpopulation<\/em> relative to the total genetic variance from an <em>entire population<\/em>. Therefore, F<sub>ST<\/sub> values range from 0 to 1 (or, sometimes you will see this stated as a percentage between 0% and 100%). The closer the F<sub>ST<\/sub> value of a population (e.g., the world\u2019s population) approaches 1, the higher the degree of genetic differentiation among subpopulations relative to the overall population (see Figure 14.24 for a detailed illustration).<\/p>\n<figure style=\"width: 561px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image4-5.jpg\" alt=\"Three cases each illustrate two populations with a mix of two types of alleles.\" width=\"561\" height=\"473\" \/><figcaption class=\"wp-caption-text\">Figure 14.24: This diagram shows a range of different case studies with which we may understand how FST is calculated in different populations. In Case 1, the gene pools of Populations 1 and 2 are 100% different from each other but possess 0% variation within themselves, so FST has a value of 1. When there is no genetic variation at all between two populations and 100% variation within them, as in Case 2, we see that FST is calculated as 0. When we look at Case 3, where variation between and within are some values between 0% and 100%, we will get a decimal figure for FST dependent upon how much variation there is between and within populations. It is through such comparisons of population genetic data that we may quantify the relative similarities or differences between and within populations, and we may thus speak to the nonexistence of \u201cracial groups\u201d that divide up our species into broad continental or racial categories. Credit: F<sub>ST<\/sub> original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Katie Nelson is under a <a class=\"rId112\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p>&nbsp;<\/p>\n<p>In his article, Lewontin (1972) identified that most of human genetic differences (85.4%) were found within local subpopulations (e.g., the Germans or Easter Islanders), whereas 8.3% were found between populations within continental human groups, and 6.3% were attributable to traditional \u201crace\u201d groups (e.g., \u201cCaucasian\u201d or \u201cAmerind\u201d). These findings have been important for scientifically rejecting the existence of biological races (Long and Kittles 2003).<\/p>\n<\/div>\n<div class=\"__UNKNOWN__\">\n<h2 class=\"import-Normal\">Talking About Human Biological Variation Going Forward<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">To conclude, utilizing the term <em>races<\/em> to describe human biological variation is not accurate or productive. Using a select few hundred genetic loci, or perhaps a number of phenotypic traits, it may be possible to assign individuals to a geographic ancestry, but what constitutes a bounded genetic or geographical grouping is both arbitrary and potentially harmful owing to ethical and historical reasons. The discipline of biological anthropology has moved past typological frameworks that shoehorn continuously variable human populations into discrete and socially constructed subsets. Improvements in the number of markers, the genetic technologies used to study variation, and the number of worldwide populations sampled have led to more nuanced understandings of human variation. It is of utmost importance that scientists make the following points clear to the public:<\/p>\n<ul>\n<li class=\"import-Normal\" style=\"text-indent: 0pt\">Today, we refer to different local human groups as \u201cpopulations.\u201d What constitutes a population should be carefully defined in scientific reports based on some geographical, linguistic, or cultural criteria and some degree of relativity to other closely or distantly related human groups.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt\">Humans have significantly less genetic variation than other primates and mammals, and all human beings on Earth share 99.9% of their overall DNA. Some of the remaining 0.1% of human variation varies on a clinal or continuous basis, such as can be seen when looking at ABO blood-type <strong>polymorphisms<\/strong> worldwide.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt\">Many biological characteristics in humans are actually determined nonconcordantly and\/or polygenically. Therefore, superiority or inferiority in human behavior or body form cannot justifiably be linked to fixed and innate differences between groups.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt\">Genetic distances are correlated with geographic distances among the global human population. This is especially apparent when we consider that genetic variation is highest in sub-Saharan Africa, and average genetic heterogeneity decreases in populations further away from the African continent in accordance with the migratory history of anatomically modern <em>Homo sapiens<\/em>.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt\">The effects of gene flow, genetic drift, and population bottlenecking are reflected in some phenotypic traits, such as cranial shape.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt\">We recognize other traits, like skin color and lactase persistence, to be the products of many millennia of natural selective pressures influencing human biology from the external environment.<\/li>\n<\/ul>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Taken together, genetic analyses of human variation do not support 20th-century (or even-earlier) concepts of race. In discussions about human variation, these genomic results help clarify how biological variation is distributed across the human population today. Taking care to think about and debate the nature of human variation is important, because although the effects and events that produced genetic differences among groups occurred in the ancient past, sociocultural concepts about race and ethnicity continue to have real social, economic, and political consequences.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Beyond talking about variation in the university setting, it is important that teachers, researchers, and students of anthropology recognize and assume the responsibility of influencing public perspectives of human variation. Race-based classification systems were developed during the colonial era, the transatlantic trafficking of kidnapped Africans and the so-called \u201cScientific Revolution\u201d by the first \u201canthropologists\u201d and scholars of humankind\u2019s variation. Unfortunately, some of their early ideas have persisted and evolved into present-day lived realities. Some of today\u2019s politicians and socioeconomic bodies have racially charged agendas that promote racism or certain kinds of economic or racial inequalities. As anthropologists, we must acknowledge that while human \u201craces\u201d are not a biological reality, their status as a (misguided) social construction does have real consequences for many people (Antrosio 2011).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">In other words, while \u201crace\u201d is a sociocultural invention, the treatment different individuals receive due to their perceived \u201crace\u201d can have significant financial, emotional, sociopolitical, and physiological costs. However\u2014and importantly assuming a \u201ccolor-blind\u201d position when it comes to the topics of \u201crace\u201d and ethnicity (especially in political discussions) is actually counterproductive, because the negative social consequences of modern \u201crace\u201d ideas could be ignored, making it harder to examine and address instances of discrimination properly (Wise 2010). Rather than shy away from these topics, we can use our scientific findings to establish socially relevant and biologically accurate ideas concerning human diversity. Today, research into genetic and phenotypic differentiation among and within various human populations continues to expand in its scope, its technological capabilities, its sample sizes, and its ethical concerns. It is thanks to such scientific work done in the past few decades that we now have a deeper understanding not only of how humans vary but also of how we are biologically a rather homogenous, intermixing world population.<\/p>\n<h2>Summary<\/h2>\n<p>Historically, most concepts of race were shaped by religious and early \u2018scientific\u2019 attempts to classify people, many of which justified inequality and racism. Today, biological anthropology emphasizes that human variation is continuous (clinal), polygenic, and shaped by both evolutionary pressures and neutral processes. Misunderstandings of race, however, continue to have serious social and medical consequences; evident in systemic racism and inequities in health care.<\/p>\n<p>Biological anthropologists now play a critical role in discrediting myths about race. By studying\u00a0 human variation, we can begin to understand evolutionary processes, adaptation, and the social implications of differences among human populations. Modern research shows that that humans are far more genetically homogenous than many other species, reinforcing a conclusion that \u2018race\u2019 is not a biological reality but a powerful social construct with real effects. Through evolutionary history and genetics, human diversity can be researched and understood, rather than than through racial categories.<\/p>\n<div class=\"textbox shaded\">\n<h2 class=\"import-Normal\">Review Questions<\/h2>\n<ul>\n<li class=\"import-Normal\">How is the genetic variation of the human species distributed worldwide?<\/li>\n<li class=\"import-Normal\">What evolutionary processes are responsible for producing genotypic\/phenotypic variation within and between human populations?<\/li>\n<li class=\"import-Normal\">Should we continue to attribute any value to \u201crace\u201d concepts older than 1950, based on our current understandings of human biological variation?<\/li>\n<li class=\"import-Normal\">How should we communicate scientific findings about human biological variation more accurately and responsibly to those outside the anthropological discipline?<\/li>\n<\/ul>\n<\/div>\n<h2 class=\"import-Normal\">Key Terms<strong><br \/>\n<\/strong><\/h2>\n<p class=\"import-Normal\"><strong>Age of Discovery<\/strong>: A period between the late 1400s and late 1700s when European explorers and ships sailed extensively across the globe in pursuit of new trading routes and territorial conquest.<\/p>\n<p class=\"import-Normal\"><strong>Ancestry<\/strong>: Biogeographical information about an individual, traced either through the study of an individual\u2019s genome, skeletal characteristics, or some other form of forensic\/archaeological evidence. Anthropologists carry out probabilistic estimates of ancestry. They attribute sets of human remains to distinctive \u201cancestral\u201d groups using careful statistical testing and should report ancestry estimations with statistical probability values.<\/p>\n<p class=\"import-Normal\"><strong>Binomial nomenclature<\/strong>: A system of naming living things developed by Linnaeus in the 1700s. It employs a scientific name made up of two italicized Latin or Greek words, with the first word capitalized and representative of an organism\u2019s genus and the second word indicating an organism\u2019s species (e.g., <em>Homo sapiens<\/em>, <em>Australopithecus afarensis<\/em>, <em>Pongo tapanuliensis<\/em>, etc.).<\/p>\n<p class=\"import-Normal\"><strong>Biological anthropology<\/strong>: A branch of study under anthropology (the study of humankind) that focuses on when and where humans and our human ancestors first originated, how we have evolved and adapted globally over time, and the reasons why we see biological variation among humans worldwide today.<\/p>\n<p class=\"import-Normal\"><strong>Biological determinism<\/strong>: The erroneous concept that an individual\u2019s behavioral characteristics are innate and determined by genes, brain size, or other physiological attributes\u2014and, notably, without the influence of social learning or the environment around the individual during development.<\/p>\n<p class=\"import-Normal\"><strong>Bony labyrinth<\/strong>: A system of interconnected canals within the auditory (ear- or hearing-related) apparatus, located in the inner ear and responsible for balance and the reception of sound waves.<\/p>\n<p class=\"import-Normal\"><strong>Cline<\/strong>: A gradient of physiological or morphological change in a single character or allele frequency among a group of species across environmental or geographical lines (e.g., skin color varies clinally, as, over many generations, human groups living nearer the equator have adapted to have more skin pigmentation).<\/p>\n<p class=\"import-Normal\"><strong>Continuous variation<\/strong>: This term refers to variation that exists between individuals and cannot be measured using distinct categories. Instead, differences between individuals within a population in relation to one particular trait are measurable along a smooth, continuous gradient.<\/p>\n<p class=\"import-Normal\"><strong>Cystic fibrosis<\/strong>: A genetic disorder in which one defective gene causes overproduction and buildup of mucus in the lungs and other bodily organs. It is most common in northern Europeans (but also occurs in other world populations).<\/p>\n<p class=\"import-Normal\"><strong>Ecological niche<\/strong>: The position or status of an organism within its community and\/or ecosystem, resulting from the organism\u2019s structural and functional adaptations (e.g., bipedalism, omnivorous diets, lactose digestion, etc.).<\/p>\n<p class=\"import-Normal\"><strong>Essentialism<\/strong>: A belief or view that an entity, organism, or human grouping has a specific set of characteristics that are fundamentally necessary to its being and classification into definitive categories.<\/p>\n<p class=\"import-Normal\"><strong>Ethnicity<\/strong>: A term used commonly in an interchangeable way with the term <em>race<\/em>, complicated because how different people define this term depends on the qualities and characteristics they use to assign a label or identity to themselves and\/or others (which may include aspects of family background, skin color, language(s) spoken, religion, physical proportions, behavior and temperament, etc.).<\/p>\n<p class=\"import-Normal\"><strong>Eugenics<\/strong>: A set of beliefs and practices that involves the controlled selective breeding of human populations with the hope of improving their heritable qualities, especially through surgical procedures like sterilization and legal rulings that affect marriage rights for interracial couples.<\/p>\n<p class=\"import-Normal\"><strong>Gene flow<\/strong>: A neutral (or nonselective) evolutionary process that occurs when genes get shared between populations.<\/p>\n<p class=\"import-Normal\"><strong>Genetic drift<\/strong>: A neutral evolutionary process in which allele frequencies change from generation to generation due to random chance.<\/p>\n<p class=\"import-Normal\"><strong>Heterogeneity<\/strong>: The quality of being diverse genetically.<\/p>\n<p class=\"import-Normal\"><strong>Homog<\/strong><strong>enous<\/strong>: The quality of being uniform genetically.<\/p>\n<p class=\"import-Normal\"><strong>Human diversity<\/strong>: Human diversity is a measure of variation that may describe how many different forms of human there are, separated or clustered into groups according to some genetic, phenotypic, or cultural trait(s). The term can be applied to culture (in which case humans can be described as significantly diverse) or genetics (in which case humans are not diverse because all humans on Earth share a majority of their genes).<\/p>\n<p class=\"import-Normal\"><strong>Human variation<\/strong>: Differences in biology, physiology, body chemistry, behavior, and culture. By measuring these differences, we understand the degrees of variation between individuals, groups, populations, or species.<\/p>\n<p class=\"import-Normal\"><strong>Isolation-by-distance model<\/strong>: A model that predicts a positive relationship between genetic distances and geographical distances between pairs of populations.<\/p>\n<p class=\"import-Normal\"><strong>Monogenetic<\/strong>: Pertaining to the idea that the origin of a species is situated in one geographic region or time (as opposed to <em>polygenetic<\/em>).<\/p>\n<p class=\"import-Normal\"><strong>Mutation<\/strong>: A gene alteration in the DNA sequence of an organism. As a random, neutral evolutionary process that occurs over the course of meiosis and early cell development, gene mutations are possible sources of variation in any given human gene pool. Genetic mutations that occur in more than 1% of a population are termed <em>polymorphisms<\/em>.<\/p>\n<p class=\"import-Normal\"><strong>Natural selection<\/strong>: An evolutionary process whereby certain traits are perpetuated through successive generations, likely owing to the advantages they give organisms in terms of chances of survival and\/or reproduction.<\/p>\n<p class=\"import-Normal\"><strong>Nonconcordance<\/strong>: The fact of genes or traits not varying with one another and instead being inherited independently.<\/p>\n<p class=\"import-Normal\"><strong>Otherness<\/strong>: In postcolonial anthropology, we now understand \u201cothering\u201d to mean any action by someone or some group that establishes a division between \u201cus\u201d and \u201cthem\u201d in relation to other individuals or populations. This could be based on linguistic or cultural differences, and it has largely been based on external characteristics throughout history.<\/p>\n<p class=\"import-Normal\"><strong>Out-of-Africa model<\/strong>: A model that suggests that all humans originate from one single group of <em>Homo sapiens<\/em> in (sub-Saharan) Africa who lived between 100,000 and 315,000 years ago and who subsequently diverged and migrated to other regions across the globe.<\/p>\n<p class=\"import-Normal\"><strong>Physical anthropology<\/strong>: This used to be the more common name given to the subdiscipline of anthropology centered upon the study of human origins, evolution and variation (also see <em>biological anthropology<\/em> above). This name for the field has gradually become less popular due to two reasons: first, it may not reflect our interests in other aspects of humankind that are not physical (such as those behavioral, cultural and spiritual), and second, using this term popular in the early decades of our field may be viewed by some as harkening back to a time when biological anthropologists conducted their work in unethical ways.<\/p>\n<p class=\"import-Normal\"><strong>Polygenetic<\/strong>: Having many different ancestries, as in older theories about human origins that involved multiple traditional groupings of humans evolving concurrently in different parts of the world before they merged into one species through interbreeding and\/or intergroup warfare. These earlier suggestions have now been overwhelmed by insurmountable evidence for a single origin of the human species in Africa (see the \u201cOut-of-Africa model\u201d).<\/p>\n<p class=\"import-Normal\"><strong>Polymorphism<\/strong>: A genetic variant within a population (caused either by a single gene or multiple genes) that occurs at a rate of over 1% among the population. Polymorphisms are responsible for variation in phenotypic traits such as blood type and skin color.<\/p>\n<p class=\"import-Normal\"><strong>Population<\/strong>: A group of humans living in a particular geographical area, with more local interbreeding within-group than interbreeding with other groups. A limited or restricted amount of gene flow between populations can occur due to geographical, cultural, linguistic, or environmental factors.<\/p>\n<p class=\"import-Normal\"><strong>Population bottlenecking<\/strong>: An event in which genetic variation is significantly reduced owing to a sharp reduction in population size. This can occur when environmental disaster strikes or as a result of human activities (e.g., genocides or group migrations). An important example of this loss in genetic variation occurred over the first human migrations out of Africa and into other continental regions.<\/p>\n<p class=\"import-Normal\"><strong>Prejudice<\/strong>: An unjustified attitude toward an individual or group that is not based on reason, whether positive (and showing preference for one group of people over another) or negative (and resulting in harm or injury to others).<\/p>\n<p class=\"import-Normal\"><strong>Race<\/strong>: The identification of a group based on a perceived distinctiveness that makes that group more similar to each other than they are to others outside the group. This may be based on cultural differences, genetic parentage, physical characteristics, behavioral attributes, or something arbitrarily and socially constructed. As a social or demographic category, perceptions of \u201crace\u201d can have real and serious consequences for different groups of people. This is despite the fact that biological anthropologists and geneticists have demonstrated that all humans are genetically homogenous and that more differences can be found within populations than between them in the overall apportionment of human biological variation. This term is sometimes used interchangeably with <em>ethnicity<\/em>.<\/p>\n<p class=\"import-Normal\"><strong>Racism<\/strong>: Any action or belief that discriminates against someone based on perceived differences in race or ethnicity.<\/p>\n<p class=\"import-Normal\"><strong>Scientific Revolution<\/strong>: A period between the 1400s and 1600s when substantial shifts occurred in the social, technological, and philosophical sense, when a scientific method based on the collection of empirical evidence through experimentation was emphasized and inductive reasoning was used to test hypotheses and interpret their results.<\/p>\n<p class=\"import-Normal\"><strong>Typolog<\/strong><strong>ical<\/strong>: Of or describing an assortment system that relies on the interpretation of qualitative similarities or differences in the study of variation among objects or people. The categorization of cultures or human groups according to \u201crace\u201d was performed with a typological approach in the earliest practice of anthropology, but this practice has since been discredited and abandoned.<\/p>\n<p class=\"import-Normal\"><strong>Variance<\/strong>: In statistics, variance measures the dispersal of a set of data around the mean or average value.<\/p>\n<h2 class=\"import-Normal\">For Further Exploration<strong><br \/>\n<\/strong><\/h2>\n<h3 class=\"import-Normal\"><strong>Videos<\/strong><\/h3>\n<p>American Medical Association (AMA). 2020. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=tqA3KvvscYc\" target=\"_blank\" rel=\"noopener\">Examining Race-Based Medicine<\/a>.\u201d YouTube, October 29. Accessed June 4, 2023.<\/p>\n<p>Crenshaw, Kimberl\u00e9. 2016. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=akOe5-UsQ2o\" target=\"_blank\" rel=\"noopener\">The Urgency of Intersectionality<\/a>.\u201d YouTube, December 7. Accessed June 4, 2023.<\/p>\n<p>Golash-Boza, Tanya. 2018. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=NQOimokvJXo\" target=\"_blank\" rel=\"noopener\">What Is Race? What Is Ethnicity? Is There a Difference?<\/a>.\u201d YouTube, October 28. Accessed June 4, 2023.<\/p>\n<p>Lasisi, Tina. 2020. \u201c<a href=\"https:\/\/naturalhistory.si.edu\/education\/teaching-resources\/social-studies\/webinar-how-hair-reveals-futility-race-categories\" target=\"_blank\" rel=\"noopener\">How Hair Reveals the Futility of Race Categories<\/a>.\u201d National Museum of Natural History webinar, October 21.<\/p>\n<p>Lasisi, Tina. 2022. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=_BEJvVFxKV4\" target=\"_blank\" rel=\"noopener\">Where Does My Skin Color Come From?<\/a>.\u201d PBS Terra, August 18. Accessed June 4, 2023.<\/p>\n<p>PBS Origins. 2018. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=CVxAlmAPHec\" target=\"_blank\" rel=\"noopener\">The Origin of Race in the USA<\/a>.\u201d YouTube, April 3. Accessed June 4, 2023.<\/p>\n<p>Roberts, Dorothy. 2016. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=KxLMjn4WPBY\" target=\"_blank\" rel=\"noopener\">The Problem with Race-Based Medicine<\/a>.\u201d YouTube, March 4. Accessed June 4, 2023.<\/p>\n<p>Vox. 2015. \u201c<a href=\"https:\/\/www.youtube.com\/watch?v=VnfKgffCZ7U\" target=\"_blank\" rel=\"noopener\">The Myth of Race, Debunked in 3 Minutes<\/a>.\u201d YouTube, January 13. Accessed June 4, 2023.<\/p>\n<h3 class=\"import-Normal\"><strong>Podcast Episodes<\/strong><\/h3>\n<p>Kwong, Emily, and Rebecca Ramirez. 2021. \u201c<a href=\"https:\/\/www.npr.org\/2021\/10\/05\/1043391809\/heres-a-better-way-to-talk-about-hair\" target=\"_blank\" rel=\"noopener\">Here\u2019s a Better Way to Talk about Hair: A 16 Minute Listen with Tina, Lasisi<\/a>\u201d NPR Short Wave, October 6. Accessed June 4, 2023.<\/p>\n<p>Speaking of Race. 2020. \u201c<a href=\"https:\/\/soundcloud.com\/user-88955638\/sets\/race-and-health?fbclid=IwAR2U1jdQL3XYFS5llGvYZ6uSrvPikuakmbxUZb--8voxgAMKrLbu7Ym7LGU\" target=\"_blank\" rel=\"noopener\">Race and Health series<\/a>.\u201d Speaking of Race, April 10. Accessed June 4, 2023.<\/p>\n<h3 class=\"import-Normal\"><strong>Websites<\/strong><\/h3>\n<p>Choices Program. 2023. \u201c<a href=\"https:\/\/www.choices.edu\/teaching-news-lesson\/an-interactive-timeline-black-activism-and-the-long-fight-for-racial-justice\/\" target=\"_blank\" rel=\"noopener\">An Interactive Timeline: Black Activism and the Long Fight for Racial Justice<\/a>.\u201d <em>Choices Program, Brown University<\/em> [Interactive Timeline], Updated February, 2023.<\/p>\n<h2 class=\"import-Normal\">References<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">American Association of Biological Anthropologists. 2020. \u201c<a href=\"https:\/\/bioanth.org\/about\/position-statements\/open-letter-our-community-response-police-brutality-against-african-americans-and-call-antiracist-action\/\" target=\"_blank\" rel=\"noopener\">An Open Letter to Our Community in Response to Police Brutality against African-Americans and a Call to Antiracist Action<\/a>\u201d. <em>American Association of Biological Anthropologists<\/em>, June 10, 2020. Accessed June 4, 2023.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Antrosio, Jason. 2011. \u201c\u2018<a href=\"https:\/\/www.livinganthropologically.com\/biological-anthropology\/race-reconciled-debunks-race\/\" target=\"_blank\" rel=\"noopener\">Race Reconciled\u2019: Race Isn\u2019t Skin Color, Biology, or Genetics<\/a>.\u201d <em>Living Anthropologically <\/em>(website), June 5, 2011; updated May 20, 2020. Accessed June 4, 2023.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Beals, Kenneth L., Courtland L. Smith, Stephen M. Dodd, J. Lawrence Angel, Este Armstrong, Bennett Blumenberg, Fakhry G. Girgis, et al. 1984. \u201cBrain Size, Cranial Morphology, Climate, and Time Machines [and Comments and Reply].\u201d <em>Current Anthropology<\/em> 25 (3): 301\u2012330.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Fran\u00e7ois Balloux, Tsunehiko Hanihara, and Andrea Manica. 2010. \u201cThe Relative Role of Drift and Selection in Shaping the Human Skull.\u201d <em>American Journal of Physical Anthropology<\/em> 141 (1): 76\u201282. https:\/\/doi.org\/10.1002\/ajpa.21115.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Fran\u00e7ois Balloux, William Amos, Tsunehiko Hanihara, and Andrea Manica. 2009. \u201cDistance from Africa, Not Climate, Explains Within-Population Phenotypic Diversity in Humans.\u201d <em>Proceedings: Biological Sciences<\/em> 276 (1658): 809\u2012814. https:\/\/doi.org\/10.1098\/rspb.2008.1563.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Noreen von Cramon-Taubadel, Andrea Manica, and Stephen J. Lycett. 2013. \u201cGlobal Geometric Morphometric Analyses of the Human Pelvis Reveal Substantial Neutral Population History Effects, Even across Sexes.\u201d <em>PloS ONE<\/em> 8 (2): e55909. https:\/\/doi.org\/10.1371\/journal.pone.0055909.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Betti, Lia, Noreen von Cramon-Taubadel, Andrea Manica, and Stephen J. Lycett. 2014. \u201cThe Interaction of Neutral Evolutionary Processes with Climatically Driven Adaptive Changes in the 3D Shape of the Human Os Coxae.\u201d <em>Journal of Human Evolution<\/em> 73 (August): 64\u201274. https:\/\/doi.org\/10.1016\/j.jhevol.2014.02.021.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Boas, Franz. 1931. \u201cRace and Progress.\u201d <em>Science<\/em> 74 1905): 1\u20128.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Bowden, Rory, Tammie S. MacFie, Simon Myers, Garrett Hellenthal, Eric Nerrienet, Ronald E. Bontrop, Colin Freeman, Peter Donnelly, and Nicholas I. Mundy. 2012. \u201cGenomic Tools for Evolution and Conservation in the Chimpanzee: <em>Pan troglodytes ellioti<\/em> Is a Genetically Distinct Population.\u201d <em>PLoS Genetics<\/em> 8 (3): e1002504. https:\/\/doi.org\/10.1371\/journal.pgen.1002504.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Campbell, Michael C., and Sarah A. Tishkoff. 2008. \u201cAfrican Genetic Diversity: Implications for Human Demographic History, Modern Human Origins, and Complex Disease Mapping.\u201d <em>Annual Review of Genomics and Human Genetics<\/em> 9: 403\u2012433.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Clee, Paul R. Sesink, Ekwoge E. Abwe, Ruffin D. Ambahe, Nicola M. Anthony, Roger Forso, Sabrina Locatelli, Fiona Maisels, et al. 2015. \u201cChimpanzee Population Structure in Cameroon and Nigeria Is Associated with Habitat Variation That May Be Lost Under Climate Change.\u201d <em>BMC Evolutionary Biology<\/em> 15: 2. https:\/\/doi.org\/10.1186\/s12862-014-0275-z.<\/p>\n<p class=\"import-Normal\">Cullors, Patrisse. 2016. \u201cAn Interview with the Founders of Black Lives Matter.\u201d TED Talks 2016, October 26\u201228. Accessed June 15, 2023. https:\/\/www.ted.com\/talks\/alicia_garza_patrisse_cullors_and_opal_tometi_an_interview_with_the_founders_of_black_lives_matter\/up-next.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Fuentes, Agust\u00edn, Rebecca Rogers Ackermann, Sheela Athreya, Deborah Bolnick, Tina Lasisi, Sang-Hee Lee, Shay-Akil McLean, and Robin Nelson. 2019. \u201cAAPA Statement on Race and Racism.\u201d <em>American Journal of Physical Anthropology<\/em> 169 (3): 400\u2012402.<\/p>\n<p class=\"import-Normal\">Garza, Alicia. 2016. \u201cAn Interview with the Founders of Black Lives Matter.\u201d TED Talks 2016, October 26\u201228. Accessed June 15, 2023. https:\/\/www.ted.com\/talks\/alicia_garza_patrisse_cullors_and_opal_tometi_an_interview_with_the_founders_of_black_lives_matter\/up-next.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Gerbault, Pascale, Anke Liebert, Yuval Itan, Adam Powell, Mathias Currat, Joachim Burger, Dallas M. Swallow, and Mark G. Thomas. 2011. \u201cEvolution of Lactase Persistence: An Example of Human Niche Construction.\u201d <em>Philosophical Transactions of the Royal Society B<\/em> 366 (1566): 863\u2012877. https:\/\/doi.org\/10.1098\/rstb.2010.0268.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Hooton, Earnest A. 1936. \u201cPlain Statements about Race.\u201d <em>Science<\/em> 83 (2161): 511\u2012513.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Hrdli\u010dka, Ale\u0161. 1918. \u201cPhysical Anthropology: Its Scope and Aims; Its History and Present Status in America. A: Physical Anthropology; Its Scopes and Aims.\u201d <em>American Journal of Physical Anthropology<\/em> 1 (1): 3\u201223.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Huxley, Julian. 1942. <em>Evolution: The Modern Synthesis<\/em>. London: Allen and Unwin.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ingram, Catherine J. E., Charlotte A. Mulcare, Yuval Itan, Mark G. Thomas, and Dallas M. Swallow. 2009. \u201cLactose Digestion and the Evolutionary Genetics of Lactase Persistence.\u201d <em>Human Genetics<\/em> 124 (6): 579\u2012591. https:\/\/doi.org\/10.1007\/s00439-008-0593-6.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Jablonski, Nina G. 2004. \u201cThe Evolution of Human Skin and Skin Color.\u201d <em>Annual Review of Anthropology<\/em> 33: 585\u2012623. https:\/\/doi.org\/10.1146\/annurev.anthro.33.070203.143955.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Jablonski, Nina G., and George Chaplin. 2000. \u201cThe Evolution of Human Skin Coloration.\u201d <em>Journal of Human Evolution<\/em> 39 (1): 57\u2012106. https:\/\/doi.org\/10.1006\/jhev.2000.0403.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Kanitz, Ricardo, Elsa G. Guillot, Sylvain Antoniazza, Samuel Neuenschwander, and J\u00e9r\u00f4me Gedout. 2018. \u201cComplex Genetic Patterns in Human Arise from a Simple Range-Expansion Model over Continental Landmasses.\u201d <em>PLoS ONE<\/em> 13 (2): e0192460.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Kronenberg, Zev N., Ian T. Fiddes, David Gordon, Shwetha Murali, Stuart Cantsilieris, Olivia S. Meyerson, Jason G. Underwood, et al. 2018. \u201cHigh-Resolution Comparative Analysis of Great Ape Genomes.\u201d <em>Science<\/em> 360 (6393): eaar6343. https:\/\/doi.org\/10.1126\/science.aar6343.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Kuzawa, Christopher W., and Elizabeth Sweet. 2009. \u201cEpigenetics and the Embodiment of Race: Development Origins of US Racial Disparities in Cardiovascular Health.\u201d <em>American Journal of Human Biology<\/em> 21 (1) : 2\u201215.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Lasisi, Tina, and Mark D. Shriver. 2018. \u201cFocus on African Diversity Confirms Complexity of Skin Pigmentation Genetics.\u201d <em>Genomic Biology<\/em> 19: 13.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Lewontin, Richard. 1972. \u201cThe Apportionment of Human Diversity.\u201d In <em>Evolutionary Biology<\/em>, vol. 6, edited by Theodosius Dobzhansky, Max K. Hecht, and William C. Steere, 381\u2012398. New York: Springer.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Linnaeus, Carl. 1758. <em>Systema Naturae<\/em>. Stockholm: Laurentius Salvius. <a class=\"rId128\" href=\"https:\/\/www.cabdirect.org\/abstracts\/20057000018.html\">https:\/\/www.cabdirect.org\/abstracts\/20057000018.html<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Liu, Hua, Franck Prugnolle, Andrea Manica, and Fran\u00e7ois Balloux. 2006. \u201cA Geographically Explicit Genetic Model of Worldwide Human-Settlement History.\u201d <em>American Journal of Human Genetics<\/em> 79 (2): 230\u2012237.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Livingstone, Frank B. 1962. \u201cOn the Nonexistence of Human Races.\u201d <em>Current Anthropology<\/em> 3 (3): 279\u2012281.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Long, Jeffery C., and Rick A. Kittles. 2003. \u201cHuman Genetic Diversity and the Nonexistence of Biological Races.\u201d <em>Human Biology<\/em> 75 (4): 449\u2012471.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Luzzatto, Lucio. 2012. \u201cSickle Cell Anaemia and Malaria.\u201d <em>Mediterranean Journal of Hematology and Infectious Diseases<\/em> 4 (1). https:\/\/doi.org\/10.4084\/MJHID.2012.065.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Manica, Andrea, William Amos, Fran\u00e7ois Balloux, and Tsunehiko Hanihara. 2007. \u201cThe Effect of Ancient Population Bottlenecks on Human Phenotypic Variation.\u201d <em>Nature<\/em> 448 (7151): 346\u2012348. https:\/\/doi.org\/10.1038\/nature05951.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">McLean, Shay-Akil. 2014. \u201c\u2018Race, Ethnicity, &amp; Racism.\u201d Decolonize ALL The Things Website, Accessed January 10, 2023. https:\/\/decolonizeallthethings.com\/learning-tools\/race-ethnicity-racism\/.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Morton, Samuel George. 1839. <em>Crania Americana, or, A Comparative View of the Skulls of Various Aboriginal Nations of North and South America.<\/em> Philadelphia: J. Dobson.<\/p>\n<p class=\"import-Normal\">Mourant, A. E., Ada C. Kope\u0107, and Kazimiera Domaniewska-Sobczak. 1976. <em>The Distribution of the Human Blood Groups and Other Polymorphisms<\/em>, 2nd edition. Oxford: Oxford University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">National Research Council (U.S.) Committee on Human Genome Diversity. 1997. <em>Evaluating Human Genetic Diversity.<\/em> Washington, D.C.: National Academies Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Omi, Michael, and Howard Winant. 2014. \u201cThe Theory of Racial Formation.\u201d In <em>Racial Formation in the United States<\/em>,3rd edition, edited by Michael Omi and Howard Winant, 105\u2012126. Routledge: New York.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Osada, Naoki. 2015. \u201cGenetic Diversity in Humans and Non-Human Primates and Its Evolutionary Consequences.\u201d <em>Genes and Genetic Systems<\/em> 90 (3): 133\u2012145.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ousley, Stephen D., Richard L. Jantz, and Donna Freid. 2009. \u201cUnderstanding Race and Human Variation: Why Forensic Anthropologists Are Good at Identifying Race.\u201d <em>American Journal of Physical Anthropology<\/em> 139 (1): 68\u201276. https:\/\/doi.org\/10.1002\/ajpa.21006.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Ponce de Le\u00f3n, Marcia S., Toetik Koesbardiati, John David Weissmann, Marco Millela, Carlos S. Reyna-Blanco, Gen Suwa, Osamu Kondo, Anna-Sapfo Malaspinas, Tim D. White, and Christoph P. E. Zollikofer. 2018. \u201cHuman Bony Labyrinth Is an Indicator of Population History and Dispersal from Africa.\u201d <em>Proceedings of the National Academy of Sciences<\/em> 115 (16): 4128\u20124133. https:\/\/doi.org\/10.1073\/pnas.1808125115.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Prado-Martinez, Javier, Peter H. Sudmant, Jeffrey M. Kidd, Heng Li, Joanna L. Kelley, Belen Lorente-Galdos, Krishna R. Veeramah, et al. 2013. \u201cGreat Ape Genetic Diversity and Population History.\u201d <em>Nature<\/em> 499 (7459): 471\u2013475. https:\/\/doi.org\/10.1038\/nature12228.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Prugnolle, Franck, Andrea Manica, and Fran\u00e7ois Balloux. 2005. \u201cGeography Predicts Neutral Genetic Diversity of Human Populations.\u201d <em>Current Biology<\/em> 15 (5): 159\u2012160.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Quillen, Ellen E., Heather L. Norton, Esteban J. Parra, Frida Lona-Durazo, Khai C. Ang, Florin Mircea Illiescu, Laurel N. Pearson, et al. 2018. \u201cShades of Complexity: New Perspectives on the Evolution and Genetic Architecture of Human Skin.\u201d <em>American Journal of Physical Anthropology<\/em> 168 (S67): 4\u201326.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Rathmann, Hannes, Hugo Reyes-Centeno, Silvia Ghirotto, Nicole Creanza, Tsunehiko Hanihara, and Katerina Harvati. 2017. \u201cReconstructing Human Population History from Dental Phenotypes.\u201d <em>Scientific Reports<\/em> 7: 12495. https:\/\/doi.org\/10.1038\/s41598-017-12621-y.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2001. \u201cGlobal Analysis of Regional Differences in Craniometric Diversity and Population Substructure.\u201d <em>Human Biology<\/em> 73 (5): 629\u2012636. https:\/\/doi.org\/10.1353\/hub.2001.0073.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2002. \u201cApportionment of Global Human Genetic Diversity Based on Craniometrics and Skin Color.\u201d <em>American Journal of Physical Anthropology<\/em> 118 (4): 393\u2012398. https:\/\/doi.org\/10.1002\/ajpa.10079.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2004. \u201cGlobal Patterns of Isolation by Distance Based on Genetic and Morphological Data.\u201d <em>Human Biology<\/em> 76 (4): 499\u2012513. https:\/\/doi.org\/10.1353\/hub.2004.0060.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Relethford, John H. 2009. \u201cRace and Global Patterns of Phenotypic Variation.\u201d <em>American Journal of Physical Anthropology<\/em> 139 (1): 16\u201222. https:\/\/doi.org\/10.1002\/ajpa.20900.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Roberts, Dorothy. 2013. <em>Fatal Invention: How Science, Politics, and Big Business Re-Create Race in the Twenty-First Century<\/em>. New York: The New Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Rosenberg, Noah A., Saurabh Mahajan, Sohini Ramachandran, Chengfeng Zhao, Jonathan K. Pritchard, and Marcus W. Feldman. 2005. \u201cClines, Clusters, and the Effect of Study Design on the Inference of Human Population Structure.\u201d <em>PLoS Genetics<\/em> 1 (6): e70. https:\/\/doi.org\/10.1371 \/journal.pgen.0010070.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Rosenberg, Noah A., Jonathan K. Pritchard, James L. Weber, Howard M. Cann, Kenneth K. Kidd, Lev A. Zhivotovsky, and Marcus W. Feldman. 2002. \u201cGenetic Structure of Human Populations.\u201d <em>Science<\/em> 298 (5602): 2381\u20122385.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Sauer, Norman J. 1992. \u201cForensic Anthropology and the Concept of Race: If Races Don\u2019t Exist, Why Are Forensic Anthropologists So Good at Identifying Them?\u201d <em>Social Science and Medicine<\/em> 34 (2): 107\u2012111. https:\/\/doi.org\/10.1016\/0277-9536(92)90086-6.<\/p>\n<p class=\"import-Normal\">Shonkoff, Jack P., Natalie Slopen, and David R. Williams. 2021. \u201cEarly Childhood Adversity, Toxic Stress, and the Impacts of Racism on the Foundations of Health.\u201d <em>Annual Review of Public Health<\/em> 42: 115\u2012134.<\/p>\n<p class=\"import-Normal\">Sjoding, Michael W., Robert P. Dickson, Theodore J. Iwashyna, Steven E. Gay, and Thomas S. Valley. 2020. \u201cRacial Bias in Pulse Oximetry Measurement.\u201d <em>The New England Journal of Medicine<\/em> 383: 2477-2478.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Staes, Nicky, Chet C. Sherwood, Katharine Wright, Marc de Manuel, Elaine E. Guevara, Tomas Marques-Bonet, Michael Kr\u00fctzen, et al. 2017. \u201cFOXP2 Variation in Great Ape Populations Offers Insight into the Evolution of Communication Skills.\u201d <em>Scientific Reports<\/em> 7 (1): 1\u201210. https:\/\/doi.org\/10.1038\/s41598-017-16844-x.<\/p>\n<p class=\"import-Normal\">Tomati, Opal. 2016. \u201cAn Interview with the Founders of Black Lives Matter.\u201d TED Talks 2016, October 26\u201228. Accessed June 15, 2023. https:\/\/www.ted.com\/talks\/alicia_garza_patrisse_cullors_and_opal_tometi_an_interview_with_the_founders_of_black_lives_matter\/up-next.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Tsai, Jennifer. 2021. \u201cCOVID-19 Is Not a Story of Race, but a Record of Racism\u2014Our Scholarship Should Reflect That Reality.\u201d <em>The American Journal of Bioethics<\/em> 21 (2): 43\u201247. https:\/\/doi.org\/10.1080\/15265161.2020.1861377.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">von Cramon-Taubadel, Noreen, and Stephen J. Lycett. 2008. \u201cBrief Communication: Human Cranial Variation Fits Iterative Founder Effect Model with African Origin.\u201d <em>American Journal of Physical Anthropology<\/em> 136 (1): 108\u2012113. https:\/\/doi.org\/10.1002\/ajpa.20775.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Weiss, Kenneth M., and Jeffrey C. Long. 2009. \u201cNon-Darwinian Estimation: My Ancestors, My Genes\u2019 Ancestors.\u201d <em>Genome Research<\/em> 19: 703\u2012710. https:\/\/doi.org\/10.1101\/gr.076539.108.19.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Williams, David W. 2018. \u201cStress and the Mental Health of Populations of Color: Advancing Our Understanding of Race-related Stressors.\u201d <em>Journal of Health and Social Behavior<\/em> 59 (4): 466\u2012485.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Wise, Tim. 2010. <em>Colorblind: The Rise of Post-Racial Politics and the Retreat from Racial Equity<\/em>. San Francisco: City Lights.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt;text-indent: 0pt\">Yudell, Michael, Dorothy Roberts, Rob DeSalle, and Sarah Tishkoff. 2016. \u201cTaking Race out of Human Genetics.\u201d <em>Science<\/em> 351 (6273): 564\u2012565. https:\/\/doi.org\/10.1126\/science.aac4951.<\/p>\n<\/div>\n<div class=\"glossary\"><span class=\"screen-reader-text\" id=\"definition\">definition<\/span><template id=\"term_410_2080\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2080\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_804\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_804\"><div tabindex=\"-1\"><div class=\"__UNKNOWN__\">\n<p class=\"import-Normal\">Jonathan M. G. Perry, Ph.D., Western University of Health Sciences<\/p>\n<p class=\"import-Normal\">Stephanie L. Canington, Ph.D., University of Pennsylvania<\/p>\n<p class=\"import-Normal\"><em>This chapter is a revision from \"<\/em><a class=\"rId7\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\"><em>Chapter 8: Primate Evolution<\/em><\/a><em>\u201d by Jonathan M. G. Perry and Stephanie L. Canington. In <\/em><a class=\"rId8\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\"><em>Explorations: An Open Invitation to Biological Anthropology, first edition<\/em><\/a><em>, edited by Beth Shook, Katie Nelson, Kelsie Aguilera, and Lara Braff, which is licensed under <\/em><a class=\"rId9\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\"><em>CC BY-NC 4.0<\/em><\/a><em>. <\/em><\/p>\n<div class=\"textbox textbox--learning-objectives\">\n<header class=\"textbox__header\">\n<h2 class=\"textbox__title\"><span style=\"color: #000000\">Learning Objectives<\/span><\/h2>\n<\/header>\n<div class=\"textbox__content\">\n<ul>\n<li>Understand the major trends in primate evolution from the origin of primates to the origin of our own species.<\/li>\n<li>Learn about primate adaptations and how they characterize major primate groups.<\/li>\n<li>Discuss the kinds of evidence that anthropologists use to find out how extinct primates are related to each other and to living primates.<\/li>\n<li>Recognize how the changing geography and climate of Earth have influenced where and when primates have thrived or gone extinct.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<p class=\"import-Normal\">The first fifty million years of primate evolution was a series of <strong>adaptive radiations<\/strong> leading to the diversification of the earliest lemurs, monkeys, and apes. The primate story begins in the canopy and understory of conifer-dominated forests, with our small, furtive ancestors subsisting at night, beneath the notice of day-active dinosaurs.<\/p>\n<p class=\"import-Normal\">From the ancient <strong>plesiadapiforms<\/strong> (archaic primates) to the earliest groups of true primates (<strong>euprimates<\/strong>) (Bloch and Boyer 2002), the origin of our own order is characterized by the struggle for new food sources and microhabitats in the arboreal setting. Climate change forced major extinctions as the northern continents became increasingly dry, cold, and seasonal and as tropical rainforests gave way to deciduous forests, woodlands, and eventually grasslands. Lemurs, lorises, and tarsiers\u2014once diverse groups containing many species\u2014became rare, except for lemurs in Madagascar, where there were no anthropoid competitors and perhaps few predators. Meanwhile, <strong>anthropoids<\/strong> (monkeys and apes) likely emerged in Asia and then dispersed across parts of the northern hemisphere, Africa, and ultimately South America. The movement of continents, shifting sea levels, and changing patterns of rainfall and vegetation contributed to the developing landscape of primate biogeography, morphology, and behavior. Today\u2019s primates provide modest reminders of the past diversity and remarkable adaptations of their extinct relatives. This chapter explores the major trends in primate evolution from the origin of the Order Primates to the beginnings of our own lineage, providing a window into these stories from our ancient past.<\/p>\n<h2 class=\"import-Normal\">Major Hypotheses About Primate Origins<\/h2>\n<p class=\"import-Normal\">For many groups of mammals, there is a key feature that led to their success. A good example is powered flight in bats. Primates lack a feature like this (see Chapter 5). Instead, if there is something unique about primates, it is probably a group of features rather than one single thing. Because of this, anthropologists and paleontologists struggle to describe an ecological scenario that could explain the rise and success of our own order. Three major hypotheses have been advanced to consider the origin of primates and to explain what makes our order distinct among mammals (Figure 9.1); these are described below.<\/p>\n<figure id=\"attachment_277\" aria-describedby=\"caption-attachment-277\" style=\"width: 634px\" class=\"wp-caption aligncenter\"><img class=\"wp-image-255\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2023\/03\/8.1.jpg\" alt=\"Primates swinging in tree, eating an insect, and eating fruit.\" width=\"634\" height=\"221\" \/><figcaption id=\"caption-attachment-277\" class=\"wp-caption-text\">Figure 9.1: The three major hypotheses are (a) the arboreal hypothesis, (b) the visual predation hypothesis, and (c) the angiosperm-primate coevolution hypothesis. Credit: Primate origin hypotheses original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by <a class=\"rId13\" href=\"https:\/\/marynelsonstudio.com\">Mary Nelson<\/a> is under a <a class=\"rId14\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Arboreal Hypothesis<\/strong><\/h3>\n<p class=\"import-Normal\">In the 1800s, many anthropologists viewed all animals in relation to humans. That is, animals that were more like humans were considered to be more \u201cadvanced\u201d and those lacking humanlike features were considered more \u201cprimitive.\u201d This way of thinking was particularly obvious in studies of primates. A more modern way of referring to members of a group that lack certain evolutionary innovations seen in other members is to call them <strong>plesiomorphic<\/strong> (literally \u201canciently shaped\u201d). The state of their morphological features is sometimes referred to as <strong>ancestral<\/strong><strong> traits<\/strong>.<\/p>\n<p class=\"import-Normal\">Thus, when anthropologists sought features that separate primates from other mammals, they focused on features that were least developed in lemurs and lorises, more developed in monkeys, and most developed in apes (Figure 9.2). Frederic Wood Jones, one of the leading anatomist-anthropologists of the early 1900s, is usually credited with the Arboreal Hypothesis of primate origins (Jones 1916). This hypothesis holds that many of the features of primates evolved to improve locomotion in the trees; this way of getting around is referred to as arboreal. For example, the grasping hands and feet of primates are well suited to gripping tree branches of various sizes and our flexible joints are good for reorienting the extremities in many different ways. A mentor of Jones, Grafton Elliot Smith, had suggested that the reduced olfactory system, acute vision, and forward-facing eyes of primates are adaptations for making accurate leaps and bounds through a complex, three-dimensional canopy (Smith 1912). The forward orientation of the eyes in primates causes the visual fields to overlap, enhancing depth perception, especially at close range. Evidence to support this hypothesis includes the facts that many extant primates are arboreal, and the plesiomorphic members of most primate groups are dedicated arborealists. The Arboreal Hypothesis was well accepted by most anthropologists at the time and for decades afterward.<\/p>\n<figure style=\"width: 663px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image27-2.png\" alt=\"Diagram shows primates descended from Plesiadapiforms.\" width=\"663\" height=\"543\" \/><figcaption class=\"wp-caption-text\">Figure 9.2: Primate family tree showing major groups. Disconnected lines show uncertainty about relationships. Two lines lead to tarsiers from different possible groups of origin. <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\" target=\"_blank\" rel=\"noopener\">A full text description of this image is available<\/a>. Credit: <a class=\"rId16\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Primate family tree (Figure 8.2)<\/a> by Jonathan M. G. Perry is under a <a class=\"rId17\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Visual Predation Hypothesis<\/strong><\/h3>\n<p class=\"import-Normal\">In the late 1960s and early 1970s, Matt Cartmill studied and tested the idea that the characteristic features of primates evolved in the context of arboreal locomotion. Cartmill noted that squirrels climb trees (and even vertical walls) very effectively, even though they lack some of the key adaptations of primates. As members of the Order Rodentia, squirrels also lack the hand and foot anatomy of primates. They have claws instead of flattened nails and their eyes face more laterally than those of primates. Cartmill reasoned that there must be some other explanation for the unique traits of primates. He noted that some nonarboreal animals share at least some of these traits with primates; for example, cats and predatory birds have forward-facing eyes that enable visual field overlap. Cartmill suggested that the unique suite of features in primates is an adaptation to detecting insect prey and guiding the hands (or feet) to catch insects (Cartmill 1972). His hypothesis emphasizes the primary role of vision in prey detection and capture; it is explicitly comparative, relying on form-function relationships in other mammals and nonmammalian vertebrates. According to Cartmill, many of the key features of primates evolved for preying on insects in this special manner (Cartmill 1974).<\/p>\n<h3 class=\"import-Normal\"><strong>Angiosperm-Primate Coevolution Hypothesis<\/strong><\/h3>\n<p class=\"import-Normal\">The visual predation hypothesis was unpopular with some anthropologists. One reason for this is that many primates today are not especially predatory. Another is that, whereas primates do seem well adapted to moving around in the smallest, terminal branches of trees, insects are not necessarily easier to find there. A counterargument to the visual predation hypothesis is the angiosperm-primate coevolution hypothesis. Primate ecologist Robert Sussman (Sussman 1991) argued that the few primates that eat mostly insects often catch their prey on the ground rather than in tree branches. Furthermore, predatory primates often use their ears more than their eyes to detect prey. Finally, most early primate fossils show signs of having been omnivorous rather than insectivorous. Instead, he argued, the earliest primates were probably seeking fruit. Fruit (and flowers) of angiosperms (flowering plants) often develop in the terminal branches. Therefore, any mammal trying to access those fruits must possess anatomical traits that allow them to maintain their hold on thin branches and avoid falling while reaching for the fruits. Primates likely evolved their distinctive visual traits and extremities in the Paleocene (approximately 65 million to 54 million years ago) and Eocene (approximately 54 million to 34 million years ago) epochs, just when angiosperms were going through a revolution of their own\u2014the evolution of large, fleshy fruit that would have been attractive to a small arboreal mammal. Sussman argued that, just as primates were evolving anatomical traits that made them more efficient fruit foragers, angiosperms were also evolving fruit that would be more attractive to primates to promote better seed dispersal. This mutually beneficial relationship between the angiosperms and the primates was termed coevolution or more specifically <strong>diffuse coevolution<\/strong>.<\/p>\n<p class=\"import-Normal\">At about the same time, D. Tab Rasmussen noted several parallel traits in primates and the South American woolly opossum, <em>Caluromys<\/em>. He argued that early primates were probably foraging on both fruits and insects (Rasmussen 1990). As is true of <em>Caluromys<\/em> today, early primates probably foraged for fruits in the terminal branches of angiosperms, and they probably used their visual sense to aid in catching insects. Insects are also attracted to fruit (and flowers), so these insects represent a convenient opportunity for a primarily fruit-eating primate to gather protein. This solution is a compromise between the visual predation hypothesis and the angiosperm-primate coevolution hypothesis. It is worth noting that other models of primate origins have been proposed, and these include the possibility that no single ecological scenario can account for the origin of primates.<\/p>\n<h2 class=\"import-Normal\">The Origins of Primates<\/h2>\n<h3 class=\"import-Normal\"><strong>Paleocene: Mammals in the Wake of Dinosaur Extinctions<\/strong><\/h3>\n<p class=\"import-Normal\">Placental mammals, including primates, originated in the Mesozoic Era (approximately 251 million to 65.5 million years ago), the Age of Dinosaurs. During this time, most placental mammals were small, probably nocturnal, and probably avoided predators via camouflage and slow, quiet movement. It has been suggested that the success and diversity of the dinosaurs constituted a kind of ecological barrier to Mesozoic mammals. The extinction of the dinosaurs (and many other organisms) at the end of the Cretaceous Period (approximately 145.5\u201365.5 million years ago) might have opened up these ecological niches, leading to the increased diversity and disparity in mammals of the Tertiary Period (approximately 65.5\u20132.5 million years ago).<\/p>\n<p class=\"import-Normal\">The Paleocene was the first epoch in the Age of Mammals. Soon after the Cretaceous-Tertiary (K-T) extinction event, new groups of placental mammals appear in the fossil record. Many of these groups achieved a broad range of sizes and lifestyles as well as a great number of species before declining sometime in the Eocene (or soon thereafter). These groups were ultimately replaced by the modern orders of placental mammals (Figure 9.3). It is unknown whether these replacements occurred gradually, for example by competitive exclusion, or rapidly, perhaps by sudden geographic dispersals with replacement. In some senses, the Paleocene might have been a time of recovery from the extinction event; it was cooler and more seasonal globally than the subsequent Eocene.<\/p>\n<figure style=\"width: 628px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image26.jpg\" alt=\"Person in front of a mural depicting forest animals.\" width=\"628\" height=\"511\" \/><figcaption class=\"wp-caption-text\">Figure 9.3: A mural of Eocene flora and fauna in North America. Credit: <a class=\"rId19\" href=\"https:\/\/flickr.com\/photos\/126377022@N07\/18404106406\">Image from page 27 of \"Annual report for the year ended June 30 ...\" (1951)<\/a> by <a class=\"rId20\" href=\"https:\/\/flickr.com\/photos\/internetarchivebookimages\/\">Internet Archive Book Images<\/a> has been designated to the <a class=\"rId21\" href=\"https:\/\/creativecommons.org\/publicdomain\/zero\/1.0\/\">public domain (CC0)<\/a>. This photograph of the mural \"Fauna and flora of middle Eocene in the Wyoming area\" by Jay Matternes, was originally published by the <a class=\"rId22\" href=\"https:\/\/www.si.edu\/\">Smithsonian<\/a>, and can be viewed in context in the <a class=\"rId23\" href=\"https:\/\/archive.org\/details\/annualreportfory1961united\/page\/7\/mode\/1up?view=theater\">online version of this book<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Plesiadapiforms, the Archaic Primates<\/strong><\/h3>\n<p class=\"import-Normal\">The Paleocene epoch saw the emergence of several families of mammals that have been implicated in the origin of primates. These are the plesiadapiforms, which are archaic primates, meaning they possessed some primate features and lacked others. The word <em>plesiadapiform <\/em>means \u201calmost adapiform,\u201d a reference to some similarities between some plesiadapiforms and some adapiforms (or adapoids; later-appearing true primates)\u2014mainly in the molar teeth. Because enamel fossilizes better than other parts of the body, the molar teeth are the parts most often found and first discovered for any new species. Thus, dental similarities were often the first to be noticed by early mammalian paleontologists, partly explaining why plesiadapiforms were thought to be primates. Major morphological differences between plesidapiforms and euprimates (true primates) were observed later when more parts of plesiadapiform skeletons were discovered. Many plesiadapiforms have unusual anterior teeth and most have digits possessing claws rather than nails. So far, no plesiadapiform ever discovered has a postorbital bar (seen in extant <strong>strepsirrhines<\/strong>) or septum (as seen in <strong>haplorhines<\/strong>), and whether or not the <strong>auditory bulla<\/strong> was formed by the <strong>petrosal bone<\/strong> remains unclear for many plesiadapiform specimens. Nevertheless, there are compelling reasons (partly from new skeletal material) for including plesiadapiforms within the Order Primates.<\/p>\n<h4 class=\"import-Normal\"><em>Geographic and Temporal Distribution<\/em><\/h4>\n<p class=\"import-Normal\"><em>Purgatorius<\/em> is generally considered to be the earliest primate. This Paleocene mammal is known from teeth that are very plesiomorphic for a primate. It has some characteristics that suggest it is a basal plesiadapiform, but there is very little to link it specifically with euprimates (see Clemens 2004). Its ankle bones suggest a high degree of mobility, signaling an arboreal lifestyle (Chester et al. 2015). <em>Purgatorius<\/em> is plesiomorphic enough to have given rise to all primates, including the plesiadapiforms. However, new finds suggest that this genus was more diverse and had more differing tooth morphologies than previously appreciated (Wilson Mantilla et al. 2021). Plesiadapiform families were numerous and diverse during parts of the Paleocene in western North America and western Europe, with some genera (e.g., <em>Plesiadapis<\/em>; see Figure 9.4) living on both continents (Figure 9.5). Thus, there were probably corridors for plesiadapiform dispersal between the two continents, and it stands to reason that these mammals were living all across North America, including in the eastern half of the continent and at high latitudes. A few plesiadapiforms have been described from Asia (e.g., <em>Carpocristes<\/em>), but the affinities of these remain uncertain.<\/p>\n<div style=\"text-align: left\">\n<table class=\"aligncenter\" style=\"width: 473.25pt\">\n<caption>Figure 9.4: Families of plesiadapiforms with example genera and traits: a table. Credit: Plesiadapiforms table original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Jonathan M. G. Perry and Stephanie L. Canington is under a <a class=\"rId24\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Content derived from Fleagle 2013.<\/caption>\n<thead>\n<tr style=\"height: 25pt\">\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Family<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Genera<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Morphology<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Location<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Age<\/strong><sup><strong>1<\/strong><\/sup><\/p>\n<p>&nbsp;<\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"Table1-R\" style=\"height: 17pt\">\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Paromomyidae<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Ignacius<\/em><\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Long, dagger-like, lower incisor.<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">North America and Europe<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Early Paleocene to Late Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 18pt\">\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Carpolestidae<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Carpolestes<\/em><\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Plagiaulacoid dentition. Limb adaptations to terminal branch feeding. Grasping big toe.<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">North America, Europe, and Asia<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Middle Paleocene to Early Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 16pt\">\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Plesiadapidae<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Plesiadapis<\/em><\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Mitten-like upper incisor. Diastema. Large body size for group.<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">North America and Europe<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Middle Paleocene to Early Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 1pt\">\n<td class=\"Table1-C\" style=\"border-top: solid #000000 0.5pt;border-right: none #000000 0pt;border-bottom: none #000000 0pt;border-left: none #000000 0pt;padding: 0pt 5.4pt 0pt 5.4pt\" colspan=\"4\">\n<p class=\"import-Normal\"><sup>1<\/sup> Derived from Fleagle 2013.<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-top: solid #000000 0.5pt;border-right: none #000000 0pt;border-bottom: none #000000 0pt;border-left: none #000000 0pt;padding: 0pt 5.4pt 0pt 5.4pt\">\n<p class=\"import-Normal\">\n<\/td>\n<\/tr>\n<tr>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<figure id=\"attachment_277\" aria-describedby=\"caption-attachment-277\" style=\"width: 555px\" class=\"wp-caption aligncenter\"><img class=\"wp-image-258 \" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image5-5-e1691791897574.png\" alt=\"Global map with not fully formed continents.\" width=\"555\" height=\"308\" \/><figcaption id=\"caption-attachment-277\" class=\"wp-caption-text\">Figure 9.5: Map of the world in the Paleocene, highlighting plesiadapiform localities on lands that would become North America, southern Europe, and eastern Asia. Credit: <a class=\"rId26\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Paleocene Map with Plesiadapiform Localities (Figure 8.4)<\/a> original to<a class=\"rId27\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\"> Expl<\/a><a class=\"rId28\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">orations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a class=\"rId29\" href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a class=\"rId30\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Localities based on Fleagle 2013, 211.<\/figcaption><\/figure>\n<h4 class=\"import-Normal\"><em>General Morphological Features<\/em><\/h4>\n<p class=\"import-Normal\">Although there is much morphological variation among the families of plesiadapiforms, some common features unite the group. Most plesiadapiforms were small, the largest being about three kilograms (approximately 7 lbs.; <em>Plesiadapis cookei<\/em>). They had small brains and fairly large snouts, with eyes that faced more laterally than in euprimates. Many species show reduction and\/or loss of the canine and anterior premolars, with the resulting formation of a rodent-like <strong>diastema <\/strong>(a pronounced gap between the premolars and the incisors, with loss of at least the canine); this probably implies a herbivorous diet. Some families appear to have had very specialized diets, as suggested by unusual tooth and jaw shapes.<\/p>\n<p class=\"import-Normal\">Arguably the most interesting and unusual family of plesiadapiforms is the Carpolestidae. They are almost exclusively from North America (with a couple of possible members from Asia), and mainly from the Middle and Late Paleocene. Their molars are not very remarkable, being quite similar to those of some other plesiadapiforms (e.g., Plesiadapidae). However, their lower posterior premolars (p4) are laterally compressed and blade-like with vertical serrations topped by tiny cuspules. This unusual dental morphology is termed <strong><em>plagiaulacoid<\/em><\/strong>  (Simpson 1933). The upper premolar occlusal surfaces are broad and are covered with many small cuspules; the blade-like lower premolar might have cut across these cuspules, between them, or both.<\/p>\n<figure style=\"width: 357px\" class=\"wp-caption alignleft\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image13-5.png\" alt=\"Front view of skull with pointed teeth.\" width=\"357\" height=\"322\" \/><figcaption class=\"wp-caption-text\">Figure 9.25: Skull of Victoriapithecus macinnesi. Credit: Victoriapithecus macinnesi skull photo taken at the Musee d'Histoire Naturelle, Paris by Ghedoghedo is under a CC BY-SA 3.0 License.<\/figcaption><\/figure>\n<p class=\"import-Normal\">Many plesiadapiforms have robust limb bones with hallmarks of arboreality. Instead of having nails, most taxa had sharp claws on most or all of the digits. The extremities show grasping abilities comparable to those of primates and some arboreal marsupials. Nearly complete skeletons have yielded a tremendous wealth of information on locomotor and foraging habits. Many plesiadapiforms appear to have been able to cling to vertical substrates (like a broad tree trunk) using their sharp claws, propelling themselves upward using powerful hindlimbs, bounding along horizontal supports, grasping smaller branches, and moving head-first down tree trunks. In carpolestids in particular, the skeleton appears to have been especially well adapted to moving slowly and carefully in small terminal branches (Figure 9.6).<\/p>\n<\/div>\n<div class=\"textbox shaded\">\n<h3 class=\"import-Normal\">Dig Deeper: Debate: Relationship of Plesiadapiforms to True Primates<\/h3>\n<p class=\"import-Normal\">In the middle of the twentieth century, treeshrews (Order Scandentia) were often considered part of the Order Primates, based on anatomical similarities between some treeshrews and primates. For many people, plesiadapiforms represented intermediates between primates and treeshrews, so plesiadapiforms were included in Primates as well.<\/p>\n<p class=\"import-Normal\">Studies of reproduction and brain anatomy in treeshrews and lemurs suggested that treeshrews are not primates (e.g., Martin 1968). This was soon followed by the suggestion to also expel plesiadapiforms (Martin 1972) from the Order Primates. Like treeshrews, plesiadapiforms lack a postorbital bar, nails, and details of the ear region that characterize true primates. Many paleoanthropologists were reluctant to accept this move to banish plesiadapiforms (e.g., F. S. Szalay, P. D. Gingerich).<\/p>\n<p class=\"import-Normal\">Later, K. Christopher Beard (1990) found that in some ways, the digits of paromomyid plesiadapiforms are actually more similar to those of dermopterans (Order Dermoptera), the closest living relatives of primates, than they are to those of primates themselves (but see Krause 1991). At the same time, Richard Kay and colleagues (1990) found that cranial circulation patterns and auditory bulla morphology in the paromomyid, <em>Ignacius <\/em>(see Figure 9.4), are more like those of dermopterans than of primates.<\/p>\n<p class=\"import-Normal\">For many anthropologists, this one-two punch effectively removed plesiadapiforms from the Order Primates. In the last two decades, the tide of opinion has turned again, with many researchers reinstating plesiadapiforms as members of the Order Primates. New and more complete specimens demonstrate that the postcranial skeletons of plesiadapiforms, including the hands and feet, were primate-like, not dermorpteran-like (Bloch and Boyer 2002, 2007). New fine-grained CT scans of relatively complete plesiadapiform skulls revealed that they share some key traits with primates to the exclusion of other placental mammals (Bloch and Silcox 2006). Most significant was the suggestion that <em>Carpolestes simpsoni <\/em>possessed an auditory bulla formed by the <strong>petrosal <\/strong><strong>bone<\/strong>, like in all living primates.<\/p>\n<p class=\"import-Normal\">The debate about the status of plesiadapiforms continues, owing to a persistent lack of key bones in some species and owing to genuine complexity of the anatomical traits involved. Maybe plesiadapiforms were the ancestral stock from which all primates arose, with some plesiadapiforms (e.g., carpolestids) nearer to the primate <strong>stem<\/strong> than others.<\/p>\n<\/div>\n<div class=\"__UNKNOWN__\">\n<h3 class=\"import-Normal\"><strong>Adapoids and Omomyoids, the First True Primates<\/strong><\/h3>\n<h4 class=\"import-Normal\"><em>Geographic and Temporal Distribution<\/em><\/h4>\n<p class=\"import-Normal\">The first universally accepted fossil primates are the adapoids (Superfamily <strong>Adapoidea<\/strong>) and the omomyoids (Superfamily <strong>Omomyoidea)<\/strong>. These groups become quite distinct over evolutionary time, filling mutually exclusive niches for the most part. However, the earliest adapoids are very similar to the earliest omomyoids.<\/p>\n<p class=\"import-Normal\">The adapoids were mainly diurnal and herbivorous, with some achieving larger sizes than any plesiadapiforms (10 kg; 22 lbs.). By contrast, the omomyoids were mainly nocturnal, insectivorous and frugivorous, and small.<\/p>\n<p class=\"import-Normal\">Both groups appear suddenly at the start of the Eocene, where they are present in western North America, western Europe, and India (Figure 9.7). This wide dispersal of early primates was probably due to the presence of rainforest corridors extending far into northern latitudes.<\/p>\n<figure id=\"attachment_277\" aria-describedby=\"caption-attachment-277\" style=\"width: 539px\" class=\"wp-caption aligncenter\"><img class=\"wp-image-260\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image22-3-e1691792023503.png\" alt=\"Global map with not fully formed continents and omomyoid localities.\" width=\"539\" height=\"317\" \/><figcaption id=\"caption-attachment-277\" class=\"wp-caption-text\">Figure 9.7: Map of the world in the Eocene, highlighting adapoid and omomyoid localities on lands that would become North America, southern Europe, Africa, and Asia. Credit: <a class=\"rId36\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Eocene Map with Adapoid and Omomyoid Localities (Figure 8.6)<\/a> original to <a class=\"rId37\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a class=\"rId38\" href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a class=\"rId39\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Localities based on Fleagle 2013, 229.<\/figcaption><\/figure>\n<p class=\"import-Normal\">In North America and Europe, both groups achieved considerable diversity in the Middle Eocene, then mostly died out at the end of that epoch (Figure 9.8). In some Eocene rock formations in the western United States, adapoids and omomyoids make up a major part of the mammalian fauna. The Eocene of India has yielded a modest diversity of euprimates, some of which are so plesiomorphic that it is difficult to know whether they are adapoids or omomyoids (or even early anthropoids).<\/p>\n<div style=\"text-align: left\">\n<table class=\"aligncenter\" style=\"width: 473.25pt\">\n<caption>Figure 9.8: Families of adapoids and omomyoids with example genera and traits: a table. Credit: Adapoids and omomyoids table original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Jonathan M. G. Perry and Stephanie L. Canington is under a <a class=\"rId40\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Content derived from Fleagle 2013.<\/caption>\n<thead>\n<tr style=\"height: 25pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Family<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Genera<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Morphology<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Location<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Age<\/strong><sup><strong>1<\/strong><\/sup><\/p>\n<p>&nbsp;<\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"Table2-R\" style=\"height: 18pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Cercamoniidae<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Donrussellia<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Variable in tooth number and jaw shape.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Europe and Asia<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Early to Late Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Asiadapidae<sup>2<\/sup><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Asiadapis<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Plesiomorphic teeth and jaw resemble early Omomyids.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Asia<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Early Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Caenopithecidae<sup>3<\/sup><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Darwinius<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Robust jaws with crested molars. Fewer premolars.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Europe, Africa, North America, and Asia<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Middle to Late Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Adapidae<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Adapis<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Fused mandible. Long molar crests. Large size and large chewing muscles.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Europe<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Late Eocene to Early Oligocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Sivaladapidae<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Sivaladapis<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Some large with robust jaws.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Asia<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Middle Eocene to Late Miocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Notharctidae<sup>4<\/sup><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Notharctus<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Canine sexual dimorphism. Lemur-like skull. Clinging and leaping adaptations.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">North America and Europe<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Early to Middle Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Omomyidae<sup>5<\/sup><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Teilhardina<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Small, nocturnal, frugivorous or insectivorous. Tarsier-like skull in some.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">North America, Europe, and Asia<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Early Eocene to Early Miocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 16pt\">\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Microchoeridae<sup>6<\/sup><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Necrolemur<\/em><\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Long bony ear tubes. Tarsier-like lower limb adaptations for leaping.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Europe and Asia<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Early Eocene to Early Oligocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table2-R\" style=\"height: 1pt\">\n<td class=\"Table2-C\" style=\"border-top: solid #000000 0.5pt;border-right: none #000000 0pt;border-bottom: none #000000 0pt;border-left: none #000000 0pt;padding: 0pt 5.4pt 0pt 5.4pt\" colspan=\"4\">\n<p class=\"import-Normal\"><sup>1<\/sup> Derived from Fleagle 2013.<\/p>\n<p class=\"import-Normal\"><sup>2<\/sup> See Dunn et al. 2016 and Rose et al. 2018.<\/p>\n<p class=\"import-Normal\"><sup>3<\/sup> See Kirk and Williams 2011 and Seiffert et al. 2009.<\/p>\n<p class=\"import-Normal\"><sup>4<\/sup> See Gregory 1920.<\/p>\n<p class=\"import-Normal\"><sup>5<\/sup> See Beard and MacPhee 1994 and Strait 2001.<\/p>\n<p class=\"import-Normal\"><sup>6<\/sup> See Schmid 1979.<\/p>\n<\/td>\n<td class=\"Table2-C\" style=\"border-top: solid #000000 0.5pt;border-right: none #000000 0pt;border-bottom: none #000000 0pt;border-left: none #000000 0pt;padding: 0pt 5.4pt 0pt 5.4pt\">\n<p class=\"import-Normal\">\n<\/td>\n<\/tr>\n<tr>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"import-Normal\">Adapoids and omomyoids barely survived the Eocene-Oligocene extinctions, when colder temperatures, increased seasonality, and the retreat of rainforests to lower latitudes led to changes in mammalian biogeography. In North America, one genus (originally considered an omomyoid but recently reclassified as Adapoidea) persisted until the Miocene: <em>Ekgmowechashala<\/em> (Rose and Rensberger 1983). This taxon has highly unusual teeth and might have been a late immigrant to North America from Asia. In Asia, one family of adapoids, the Sivaladapidae, retained considerable diversity as late as the Late Miocene.<\/p>\n<h4 class=\"import-Normal\"><em>Adapoid Diversity<\/em><\/h4>\n<p class=\"import-Normal\">Adapoids were very diverse, particularly in the Eocene of North America and Europe. They can be divided into six families, with a few species of uncertain familial relationship. As a group, adapoids have some features in common, although much of what they share is plesiomorphic. Important features include the hallmarks of euprimates: postorbital bar, flattened nails, grasping extremities, and a petrosal bulla (Figures 9.9 and 9.10). In addition, some adapoids retain the ancestral dental formula of 2.1.4.3; that is, in each quadrant of the mouth, there are two incisors, one canine, four premolars, and three molars. In general, the incisors are small compared to the molars, but the canines are relatively large, with sexual dimorphism in some species. Cutting crests on the molars are well developed in some species, and the two halves of the mandible were fused at the midline in some species. Some adapoids were quite small (<em>Anchomomys <\/em>at a little over 100 g), and some were quite large (<em>Magnadapis<\/em> at 10 kg; 22 lbs.). Furthermore, the spaces and attachment features for the chewing muscles were truly enormous in some species, suggesting that these muscles were very large and powerful. Taken together, this suggests an overall adaptive profile of diurnal herbivory. The canine sexual dimorphism in some species suggests a possible mating pattern of polygyny, as males in polygynous primate species often compete with each other for mates and have especially large canine teeth.<\/p>\n<figure style=\"width: 548px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image18-1.jpg\" alt=\"Three partial animal crania.\" width=\"548\" height=\"350\" \/><figcaption class=\"wp-caption-text\">Figure 9.9: Representative crania of Adapidae from Museum d\u2019Histoire Naturelle Victor Brun, a natural history museum in Montauban, France. The white scale bar is 1 cm long. Credit: <a class=\"rId43\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Representative crania of adapids (European adapoids, (Figure 8.7)<\/a> from the <a class=\"rId44\" href=\"https:\/\/www.museum.montauban.com\/\">Museum d\u2019Histoire Naturelle Victor Brun in Montauban, France<\/a> original to <a class=\"rId45\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology <\/a>by Jonathan M. G. Perry is under a <a class=\"rId46\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<figure style=\"width: 547px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image19-2.jpg\" alt=\"Side views of small rodentlike skeleton with long tail.\" width=\"547\" height=\"525\" \/><figcaption class=\"wp-caption-text\">Figure 9.10: Darwinius masillae, a member of the Caenopithecidae. The slab on the left is Plate A and the slab on the right is Plate B. The parts of the skeleton in B that are outside of the dashed lines were fabricated. Credit: <a class=\"rId48\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Darwinius%20masillae%20holotype%20slabs.jpg\">Darwinius masillae holotype slabs<\/a> by Jens L. Franzen, Philip D. Gingerich, J\u00f6rg Habersetzer1, J\u00f8rn H. Hurum, Wighart von Koenigswald, B. Holly Smith is under a <a class=\"rId49\" href=\"https:\/\/creativecommons.org\/licenses\/by\/2.5\/legalcode\">CC BY 2.5 License<\/a>. Originally from Franzen et al. 2009.<\/figcaption><\/figure>\n<h4 class=\"import-Normal\"><em>Omomyoid Diversity<\/em><\/h4>\n<p class=\"import-Normal\">Like adapoids, omomyoids appeared suddenly at the start of the Eocene and then became very diverse with most species dying out before the Oligocene. Omomyoids are known from thousands of jaws with teeth, relatively complete skulls for about a half-dozen species, and very little postcranial material. Omomyoids were relatively small primates, with the largest being less than three kilograms (approximately 7 lbs.; <em>Macrotarsius montanus<\/em>). All known crania possess a postorbital bar, which in some has been described as \u201cincipient closure.\u201d Some\u2014but not all\u2014known crania have an elongated bony ear tube extending lateral to the location of the eardrum, a feature seen in living tarsiers and <strong>catarrhines<\/strong>. The anterior teeth tend to be large, with canines that are usually not much larger than the incisors. Often it is difficult to distinguish closely related species using molar morphology, but the premolars tend to be distinct from one species to another. The postcranial skeleton of most omomyoids shows hallmarks of leaping behavior reminiscent of that of tarsiers. In North America, omomyoids became very diverse and abundant. In fact, omomyoids from Wyoming are sufficiently abundant and from such stratigraphically controlled conditions that they have served as strong evidence for the gradual evolution of anatomical traits over time (Rose and Bown 1984).<\/p>\n<p class=\"import-Normal\"><em>Teilhardina <\/em>(Figure 9.11; see Figure 9.2) is one of the earliest and arguably the most plesiomorphic of omomyoids. <em>Teilhardina<\/em> has several species, most of which are from North America, with one from Europe (<em>T. belgica<\/em>) and one from Asia (<em>T. asiatica<\/em>). The species of this genus are anatomically similar and the deposits from which they are derived are roughly contemporaneous. Thus, this small primate likely dispersed across the northern continents very rapidly (Smith et al. 2006).<\/p>\n<figure style=\"width: 545px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image3-1.jpg\" alt=\"World map with primates jumping across forested areas.\" width=\"545\" height=\"289\" \/><figcaption class=\"wp-caption-text\">Figure 9.11: A map of the world during the early Eocene showing one hypothesis for the direction of dispersal of the omomyoid Teilhardina. The map depicts primates hopping from continent to continent (East to West) via the forest corridors at high latitudes. Credit: <a href=\"https:\/\/www.pnas.org\/content\/103\/30\/11223\">Paleogeographic map showing hypothetical migration routes of Teilhardina (Figure 1)<\/a> by Thierry Smith, Kenneth D. Rose, and Philip D. Gingerich. 2006. <a href=\"https:\/\/www.pnas.org\/about\/rights-permissions\">Proceedings of the National Academy of Sciences of the United States of America <\/a>103 (30): 11223\u201311227. Copyright (2006) National Academy of Sciences. Image <a href=\"https:\/\/www.pnas.org\/about\/rights-permissions\">is used for non-commercial and educational purposes as outlined by PNAS.<\/a><\/figcaption><\/figure>\n<h2 class=\"import-Normal\">The Emergence of Modern Primate Groups<\/h2>\n<h3 class=\"import-Normal\"><strong>Origins of Crown Strepsirrhines<\/strong><\/h3>\n<p class=\"import-Normal\">Until the turn of this century, very little was known about the origins of the <strong>crown<\/strong> (living) strepsirrhines. The Quaternary record of Madagascar contains many amazing forms of lemurs, including giant sloth-like lemurs, lemurs with perhaps monkey-like habits, lemurs with koala-like habits, and even a giant aye-aye (Godfrey and Jungers 2002). However, in Madagascar, early Tertiary continental sediments are lacking, and there is no record of lemur fossils before the Pleistocene.<\/p>\n<p class=\"import-Normal\">The fossil record of galagos is slightly more informative. Namely, there are Miocene African fossils that are very likely progenitors of lorisids (Simpson 1967). However, these are much like modern galagos and do not reveal anything about the relationship between crown strepsirrhines and Eocene fossil primates (but see below regarding <em>Propotto<\/em>). A similar situation exists for lorises in Asia: there are Miocene representatives, but these are substantially like modern lorises. The discovery of the first definite <strong>toothcomb<\/strong> canine (a hallmark of stresirrhines) in 2003 provided the \u201csmoking gun\u201d for the origin of crown strepsirrhines (Seiffert et al. 2003). Recently, several other African primates have been recognized as having strepsirrhine affinities (Marivaux et al. 2013; Seiffert 2012). The enigmatic Fayum primate <em>Plesiopithecus<\/em> is known from a skull that has been compared to aye-ayes and to lorises (Godinot 2006; Simons and Rasmussen 1994a).<\/p>\n<p class=\"import-Normal\">The now-recognized diversity of stem strepsirrhines from the Eocene and Oligocene of Afro-Arabia is strong evidence to suggest that strepsirrhines originated in that geographic area. This implies that lorises dispersed to Asia subsequent to an African origin. It is unknown what the first strepsirrhines in Madagascar were like. However, it seems likely that the lemuriform-lorisiform split occurred in continental Africa, followed by dispersal of lemuriform stock to Madagascar. Recent evidence suggests that <em>Propotto<\/em>, a Miocene primate from Kenya originally described as a potto antecedent, actually forms a clade with <em>Plesiopithecus <\/em>and the aye-aye; this might suggest that strepsirrhines dispersed to Madagascar from continental Africa more than once (Gunnell et al. 2018).<\/p>\n<h3 class=\"import-Normal\"><strong>The Fossil Record of Tarsiers<\/strong><\/h3>\n<p class=\"import-Normal\">Tarsiers are so unusual that they fuel major debates about primate taxonomy. Tarsiers today are moderately diverse but geographically limited and not very different in their ecological habits\u2014especially considering that the split between them and their nearest living relative probably occurred over 50 million years ago. If omomyoids are excluded, then the fossil record of tarsiers is very limited. Two fossil species from the Miocene of Thailand have been placed in the genus <em>Tarsius<\/em>, as has an Eocene fossil from China (Beard et al. 1994). These, and <em>Xanthorhysis<\/em> from the Eocene of China, are all very tarsier-like. In fact, it is striking that <em>Tarsius eocaenus<\/em> from China was already so tarsier-like as early as the Eocene. This suggests that tarsiers achieved their current morphology very early in their evolution and have remained more or less the same while other primates changed dramatically. Two additional genera, <em>Afrotarsius<\/em> from the Oligocene of Egypt and Libya and <em>Afrasia<\/em> from the Eocene of Myanmar, have also been implicated in tarsier origins, though the relationship between them and tarsiers is unclear (Chaimanee et al. 2012). More recently, a partial skeleton of a small Eocene primate from China, <em>Archicebus achilles<\/em> (dated to approximately 55.8 million to 54.8 million years ago), was described as the most basal tarsiiform (Ni et al. 2013). This primate is reconstructed as a diurnal insectivore and an arboreal quadruped that did some leaping\u2014but not to the specialized degree seen in living tarsiers. The anatomy of the eye in living tarsiers suggests that their lineage passed through a diurnal stage, so <em>Archicebus<\/em> (and diurnal omomyoids) might represent such a stage.<\/p>\n<h3 class=\"import-Normal\"><strong>Climate Change and the Paleogeography of Modern Primate Origins<\/strong><\/h3>\n<p class=\"import-Normal\">Changing global climate has had profound effects on primate dispersal patterns and ecological habits over evolutionary time. Primates today are strongly tied to patches of trees and particular plant parts such as fruits, seeds, and immature leaves. It is no surprise, then, that the distribution of primates mirrors the distribution of forests. Today, primates are most diverse in the tropics, especially in tropical rainforests. Global temperature trends across the Tertiary have affected primate ranges. Following the Cretaceous-Tertiary extinction event, cooler temperatures and greater seasonality characterized the Paleocene. In the Eocene, temperatures (and probably rainfall) increased globally and rainforests likely extended to very high latitudes. During this time, euprimates became diverse. With cooling and increased aridity at the end of the Eocene, many primate extinctions occurred in the northern continents and the surviving primates were confined to lower latitudes in South America, Afro-Arabia, Asia, and southern Europe. Among these survivors are the progenitors of the living groups of primates: lemurs and lorises, tarsiers, <strong>platyrrhines<\/strong> (monkeys of the Americas), and catarrhines (monkeys and apes of Africa and Asia) (Figure 9.12).<\/p>\n<figure id=\"attachment_277\" aria-describedby=\"caption-attachment-277\" style=\"width: 539px\" class=\"wp-caption aligncenter\"><img class=\"wp-image-264\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image2-5-e1691791570984.png\" alt=\"Map of world with gray continents.\" width=\"539\" height=\"306\" \/><figcaption id=\"caption-attachment-277\" class=\"wp-caption-text\">Figure 9.12: Map of key localities of early anthropoids on land that becomes Africa and southern Asia. Credit: <a class=\"rId56\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Oligocene Map with Key Early Anthropoid Localities (Figure 8.10)<\/a> original to <a class=\"rId57\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a class=\"rId58\" href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a class=\"rId59\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Localities based on Fleagle 2013, 265.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Competing Hypotheses for the Origin of Anthropoids<\/strong><\/h3>\n<p class=\"import-Normal\">There is considerable debate among paleoanthropologists as to the geographic origins of anthropoids. In addition, there is debate regarding the source group for anthropoids. Three different hypotheses have been articulated in the literature. These are the adapoid origin hypothesis, the omomyoid origin hypothesis, and the tarsier origin hypothesis (Figure 9.13).<\/p>\n<figure style=\"width: 419px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image24-1-1.jpg\" alt=\"Diagrams show three relationships among primate groups.\" width=\"419\" height=\"742\" \/><figcaption class=\"wp-caption-text\">Figure 9.13: Competing models of anthropoid origins. Branch lengths are not to scale. The omomyoid origin model and tarsier origin model do not make specific reference to the evolutionary position of strepsirrhines; however, they were included here for completeness. <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\">A full text description of this image is available<\/a>. Credit: <a class=\"rId61\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Competing Trees for Anthropoid Origins (Figure 8.11)<\/a> original to <a class=\"rId62\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Jonathan M. G. Perry is under a <a class=\"rId63\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<h4 class=\"import-Normal\"><em>Adapoid Origin Hypothesis<\/em><\/h4>\n<p class=\"import-Normal\">Resemblances between some adapoids and some extant anthropoids include fusion of the <strong>mandibular symphysis<\/strong>, overall robusticity of the chewing system, overall large body size, features that signal a diurnal lifestyle (like relatively small eye sockets), and ankle bone morphology. Another feature in common is canine sexual dimorphism, which is present in some species of adapoids (probably) and in several species of anthropoids.<\/p>\n<p class=\"import-Normal\">These features led some paleoanthropologists in the last half of the 20th century to suggest that anthropoids came from adapoid stock (Gingerich 1980; Simons and Rasmussen 1994b). One of the earliest supporters of the link between adapoids and anthropoids was Hans Georg Stehlin, who described much of the best material of adapoids and compared these Eocene primates to South American monkeys (Stehlin 1912). In more recent times, the adapoid origin hypothesis was reinforced by resemblances between these European adapoids (especially <em>Adapis <\/em>and <em>Leptadapis<\/em>) and some early anthropoids from the Fayum Basin (e.g., <em>Aegyptopithecus<\/em>, see below; Figure 9.14).<\/p>\n<div style=\"text-align: left\">\n<table class=\"aligncenter\" style=\"width: 473.25pt\">\n<caption>Figure 9.14: Families of early anthropoids with example genera and traits: a table. Credit: Early anthropoids table original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Jonathan M. G. Perry and Stephanie L. Canington is under a <a class=\"rId64\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Content derived from Fleagle 2013.<\/caption>\n<thead>\n<tr style=\"height: 25pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Family<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Genera<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Morphology<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Location<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Age<\/strong><sup><strong>1<\/strong><\/sup><\/p>\n<p>&nbsp;<\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"Table3-R\" style=\"height: 18pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Propliopithecidae<sup>2<\/sup><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Aegyptopithecus<\/em><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Large size. Cranial sexual dimorphism, large canines. Robust jaws and rounded molars. Partially ossified ear tube (in some). Robust skeleton; quadruped.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Africa<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Late Eocene to Early Oligocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table3-R\" style=\"height: 16pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Parapithecidae<sup>3<\/sup><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Apidium<\/em><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Medium size. Retention of three premolars per quadrant. Rounded molars and premolars with large central cusps. Adaptations for leaping in the lower limb.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Africa<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Late Eocene to Late Oligocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table3-R\" style=\"height: 16pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Proteopithecidae<sup>4<\/sup><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Proteopithecus<\/em><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Small size. Retention of three premolars per quadrant. Arboreal quadrupeds that ate fruit.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Africa<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Late Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table3-R\" style=\"height: 16pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Oligopithecidae<sup>5<\/sup><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Catopithecus<\/em><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Small size. Skull has postorbital septum and unfused mandible. Deep jaws. Diet of fruits. Generalized quadruped.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Africa<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Late Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table3-R\" style=\"height: 16pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Eosimiidae<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Eosimias<\/em><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Deep jaw with vertical unfused symphysis. Pointed incisors and canines. Crowded premolars.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Asia<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Middle Eocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table3-R\" style=\"height: 16pt\">\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Amphipithecidae<sup>6<\/sup><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\"><em>Pondaungia<\/em><\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Deep jaws. Molars generally rounded with wide basins.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Asia<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt 0pt 5.4pt;border: solid #000000 0.5pt\">\n<p class=\"import-Normal\">Middle Eocene to Early Oligocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table3-R\" style=\"height: 1pt\">\n<td class=\"Table3-C\" style=\"border-top: solid #000000 0.5pt;border-right: none #000000 0pt;border-bottom: none #000000 0pt;border-left: none #000000 0pt;padding: 0pt 5.4pt 0pt 5.4pt\" colspan=\"4\">\n<p class=\"import-Normal\"><sup>1<\/sup> Derived from Fleagle 2013.<\/p>\n<p class=\"import-Normal\"><sup>2<\/sup> See Gebo and Simons 1987 and Simons et al. 2007.<\/p>\n<p class=\"import-Normal\"><sup>3<\/sup> See Feagle and Simons 1995 and Simons 2001.<\/p>\n<p class=\"import-Normal\"><sup>4<\/sup> See Simons and Seiffert 1999.<\/p>\n<p class=\"import-Normal\"><sup>5<\/sup> See Simons and Rasmussen 1996.<\/p>\n<p class=\"import-Normal\"><sup>6<\/sup> See Kay et al. 2004.<\/p>\n<\/td>\n<td class=\"Table3-C\" style=\"border-top: solid #000000 0.5pt;border-right: none #000000 0pt;border-bottom: none #000000 0pt;border-left: none #000000 0pt;padding: 0pt 5.4pt 0pt 5.4pt\">\n<p class=\"import-Normal\">\n<\/td>\n<\/tr>\n<tr>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<td><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p class=\"import-Normal\">Unfortunately for the adapoid hypothesis, most of the shared features listed above probably emerged independently in the two groups as adaptations to a diet of hard and\/or tough foods. For example, fusion of the mandibular symphysis likely evolved as a means to strengthen the jaw against forces that would pull the two halves away from each other, in the context of active chewing muscles on both sides of the head generating great bite forces. This context would also favor the development of robust jaws, large chewing muscles, shorter faces, and some other features shared by some adapoids and some anthropoids.<\/p>\n<p class=\"import-Normal\">As older and more plesiomorphic anthropoids were found in the Fayum Basin, it became clear that the earliest anthropoids from Africa did not possess these features of jaw robusticity (Seiffert et al. 2009). Furthermore, many adapoids never evolved these features. Fusion of the mandibular symphysis in adapoids is actually quite different from that in anthropoids and probably occurred during juvenile development in the former (Beecher 1983; Ravosa 1996). Eventually, the adapoid origin hypothesis fell out of favor among most paleoanthropologists, although the description of <em>Darwinius<\/em> is a recent revival of that idea (Franzen et al. 2009; but see Seiffert et al. 2009, Williams et al. 2010b).<\/p>\n<h4 class=\"import-Normal\"><em>Omomyoid Origin Hypothesis<\/em><\/h4>\n<p class=\"import-Normal\">Similarities in cranial and hindlimb morphology between some omomyoids and extant tarsiers have led to the suggestion that tarsiers arose from some kind of omomyoid. In particular, <em>Necrolemur<\/em> has many features in common with tarsiers, as does the North American <em>Shoshonius<\/em>, which is known from a few beautifully preserved (although distorted) crania. Tarsiers and <em>Shoshonius <\/em>share exclusively some features of the base of the cranium; however, <em>Shoshonius<\/em> does not have any sign of postorbital closure, and it lacks the bony ear tube of tarsiers. Nevertheless, some of the resemblances between some omomyoids and tarsiers suggest that tarsiers might have originated from within the Omomyoidea (Beard 2002; Beard and MacPhee 1994). In this scenario, although living tarsiers and living anthropoids might be sister taxa, they might have evolved from different omomyoids, possibly separated from each other by more than 50 million years of evolution, or from anthropoids evolved from some non-omomyoid fossil group. The arguments against the omomyoid origin hypothesis are essentially the arguments <em>for<\/em> the tarsier origin hypothesis (see below). Namely, tarsiers and anthropoids share many features (especially of the soft tissues) that must have been retained for many millions of years or must have evolved convergently in the two groups. Furthermore, a key hard-tissue feature shared between the two extant groups, the postorbital septum, was not present in any omomyoid. Therefore, that feature must have arisen convergently in the two extant groups or must have been lost in omomyoids. Neither scenario is very appealing, although recent arguments for <strong>convergent evolution<\/strong> of the postorbital septum in tarsiers and anthropoids have arisen from embryology and histology of the structure (DeLeon et al. 2016).<\/p>\n<h4 class=\"import-Normal\"><em>Tarsier Origin Hypothesis<\/em><\/h4>\n<p class=\"import-Normal\">Several paleoanthropologists have suggested that there is a relationship between tarsiers and anthropoids to the exclusion of omomyoids and adapoids (e.g., Cartmill and Kay 1978; Ross 2000; Williams and Kay 1995). Tarsiers and anthropoids today share several traits, including many soft-tissue features related to the olfactory system (e.g., the loss of a hairless external nose and loss of the median cleft running from the nose to the mouth, as possessed by strepsirrhines), and aspects of the visual system (e.g., the loss of a reflective layer at the back of the eye, similarities in carotid circulation to the brain, and mode of placentation). Unfortunately, none of these can be assessed directly in fossils. Some bony similarities between tarsiers and anthropoids include an extra air-filled chamber below the middle ear cavity, reduced bones within the nasal cavity, and substantial postorbital closure; these can be assessed in fossils, but the distribution of these traits in omomyoids does not yield clear answers. Furthermore, several similarities between tarsiers and anthropoids are probably due to similarities in sensory systems, which might have evolved in parallel for ecological reasons. Although early attempts to resolve the crown primates with molecular data were sometimes equivocal or in disagreement with one another, more recent analyses (including those of short interspersed elements) suggest that tarsiers and anthropoids are sister groups to the exclusion of lemurs and lorises (Williams et al. 2010a). However, this does not address omomyoids, all of which are far too ancient for DNA extraction.<\/p>\n<p class=\"import-Normal\">The above three hypotheses are not the only possibilities for anthropoid origins. It may be that anthropoids are neither the closest sister group of tarsiers, nor evolved from adapoids or omomyoids. In recent years, two new groups of Eocene Asian primates have been implicated in the origin of anthropoids: the eosimiids and the amphipithecids. It is possible that one or the other of these two groups gave rise to anthropoids. Regardless of the true configuration of the tree for crown primates, the three major extant groups probably diverged from each other quite long ago (Seiffert et al. 2004).<\/p>\n<h3 class=\"import-Normal\"><strong>Early Anthropoid Fossils in Africa<\/strong><\/h3>\n<figure style=\"width: 526px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image7-2.jpg\" alt=\"People digging in a sandy desert.\" width=\"526\" height=\"352\" \/><figcaption class=\"wp-caption-text\">Figure 9.15: Egyptian workers sweeping Quarry I in the Fayum Basin (2004). This technique, called wind harvesting, removes the desert crust and permits wind to blow out fine sediment and reveal fossils. Credit: <a class=\"rId66\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Egyptian workers sweeping Quarry I in the Fayum Basin (2004, Figure 8.12)<\/a> by Jonathan M. G. Perry is under a <a class=\"rId67\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<figure style=\"width: 280px\" class=\"wp-caption alignleft\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image14-2.jpg\" alt=\"A person using a tool to expose bone in sand.\" width=\"280\" height=\"423\" \/><figcaption class=\"wp-caption-text\">Figure 9.16: Elwyn Laverne Simons excavating Aegyptopithecus in the Fayum Basin. Credit: <a class=\"rId69\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Elwyn Laverne Simons in the Fayum Basin (Figure 8.13)<\/a> used by permission of the <a class=\"rId70\" href=\"https:\/\/lemur.duke.edu\/\">Duke Lemur Center,<\/a> Division of Fossil Primates, is under a <a class=\"rId71\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">The classic localities yielding the greatest wealth of early anthropoid fossils are those from the Fayum Basin in Egypt (Simons 2008; Figure 9.15). The Fayum is a veritable oasis of fossil primates in an otherwise spotty early Tertiary African record. Since the 1960s, teams led by E. L. Simons have discovered several new species of early anthropoids, some of which are known from many parts of the skeleton and several individuals (Figure 9.16).<\/p>\n<p class=\"import-Normal\">The Fayum Jebel Qatrani Formation and Birket Qarun Formation between them have yielded a remarkable array of terrestrial, arboreal, and aquatic mammals. These include ungulates, bats, sea cows, elephants, hyraces, rodents, whales, and primates. Also, many other vertebrates, like water birds, were present. The area at the time of deposition (Late Eocene through Early Oligocene) was probably very wet, with slow-moving rivers, standing water, swampy conditions, and lots of trees (see Bown and Kraus 1988). In short, it was an excellent place for primates.<\/p>\n<h4 class=\"import-Normal\"><em>General Morphology of Anthropoids<\/em><\/h4>\n<p class=\"import-Normal\">The anthropoids known from the Fayum (and their close relatives from elsewhere in East Africa and Afro-Arabia) bear many of the anatomical hallmarks of extant anthropoids; however, there are plesiomorphic forms in several families that lack one or more anthropoid traits. All Fayum anthropoids known from skulls possess postorbital closure, most had fused mandibular symphyses, and most had ring-like <strong>ectotympanic<\/strong>  bones. Tooth formulae were generally either 2.1.3.3 or 2.1.2.3. Fayum anthropoids ranged in size from the very small <em>Qatrania<\/em> and <em>Biretia <\/em>(less than 500 g) to the much-larger <em>Aegyptopithecus<\/em> (approximately 7 kg; 15 lbs.). Fruit was probably the main component of the diet for most or all of the anthropoids, with some of them supplementing with leaves (Kay and Simons 1980; Kirk and Simons 2001; Teaford et al. 1996). Most Fayum anthropoids were probably diurnal above-branch quadrupeds. Some of them (e.g., <em>Apidium<\/em>; see Figure 9.14) were probably very good leapers (Gebo and Simons 1987), but none show specializations for gibbon-style suspensory locomotion. Some of the Fayum anthropoids are known from hundreds of individuals, permitting the assessment of individual variation, sexual dimorphism, and in some cases growth and development. The description that follows provides greater detail for the two best known Fayum anthropoid families, the Propliopithecidae and the Parapithecidae; the additional families are summarized briefly.<\/p>\n<h4 class=\"import-Normal\"><em>Fayum Anthropoid Families<\/em><\/h4>\n<p class=\"import-Normal\">The Propliopithecidae (see Figure 9.14) include the largest anthropoids from the fauna, and they are known from several crania and some postcranial elements. They have been suggested to be stem catarrhines, although perhaps near the split between catarrhines and platyrrhines. The best known propliopithecid is <em>Aegyptopithecus<\/em>, known from many teeth, crania, and postcranial elements (Figure 9.17) .<\/p>\n<figure style=\"width: 431px\" class=\"wp-caption alignright\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image4-2-1.jpg\" alt=\"Two animal skull side views.\" width=\"431\" height=\"281\" \/><figcaption class=\"wp-caption-text\">Figure 9.17: Female (left) and male (right) skull material for Aegyptopithecus zeuxis. The mandibles are not associated with the crania. Credit: <a href=\"https:\/\/www.pnas.org\/doi\/full\/10.1073\/pnas.0703129104#supplementary-materials\">Female and male cranium of A. zeuxi (03129Fig5, Supporting Information)<\/a> by Elwyn L. Simons, Erik R. Seiffert, Timothy M. Ryan, and Yousry Attia. 2007. <a href=\"https:\/\/www.pnas.org\/about\/rights-permissions\">Proceedings of the National Academy of Sciences of the United States of America<\/a> 104 (21): 8731\u20138736. Copyright (2007) National Academy of Sciences. Image <a href=\"https:\/\/www.pnas.org\/about\/rights-permissions\">is used for non-commercial and educational purposes as outlined by PNAS.<\/a><\/figcaption><\/figure>\n<p class=\"import-Normal\">Parapithecidae are an extremely abundant and unusual family of anthropoids from the Fayum. The parapithecid <em>Apidium<\/em> is known from many jaws with teeth, crushed and distorted crania, and several skeletal elements. <em>Parapithecus<\/em> is known from cranial material including a beautiful, undistorted cranium. This genus shows extreme reduction of the incisors, including complete absence of the lower incisors in <em>P. grangeri <\/em>(Simons 2001). This trait is unique among primates. Parapithecids were once thought to be the ancestral stock of platyrrhines; however, their platyrrhine-like features are probably ancestral retentions, so the most conservative approach is to consider them stem anthropoids.<\/p>\n<p class=\"import-Normal\">The Proteopithecidae were small frugivores that probably mainly walked along horizontal branches on all fours. They are considered stem anthropoids. The best known genus, <em>Proteopithecus<\/em>, is represented by dentitions, crania, and postcranial elements.<\/p>\n<p class=\"import-Normal\">The Oligopithecidae share a mixture of traits that makes them difficult to classify more specifically within anthropoids. The best known member, <em>Catopithecus<\/em>, is known from crania that demonstrate a postorbital septum and from mandibles that lack symphyseal fusion. They share the catarrhine tooth formula of 2.1.2.3 and have a canine honing complex that involves the anterior lower premolar. The postcranial elements known for the group suggest generalized arboreal quadrupedalism. The best known member, <em>Catopithecus<\/em>, is known from crania that demonstrate a postorbital septum and from mandibles that lack symphyseal fusion (Simons and Rasmussen 1996). The jaws are deep, with broad muscle attachment areas and crested teeth. <em>Catopithecus<\/em> was probably a little less than a kilogram in weight.<\/p>\n<p class=\"import-Normal\">Other genera of putative anthropoids from the Fayum include the very poorly known <em>Arsinoea<\/em>, the contentious <em>Afrotarsius<\/em>, and the enigmatic <em>Nosmips<\/em>. The last of these possesses traits of several major primate <strong>clades<\/strong> and defies classification (Seiffert et al. 2010).<\/p>\n<h3 class=\"import-Normal\"><strong>Early Anthropoid Fossils in Asia<br style=\"clear: both\" \/><\/strong><\/h3>\n<p class=\"import-Normal\">For the last half of the 1900s, researchers believed that Africa was the unquestioned homeland of early anthropoids (see Fleagle and Kay 1994). However, two very different groups of primates from Asia soon began to change that. One was an entirely new discovery (Eosimiidae), and the other was a poorly known group discovered decades prior (Amphipithecidae). Soon, attention on anthropoid origins began to shift eastward (see Ross and Kay 2004; Simons 2004). If anthropoids arose in Asia instead of Africa, then this implies that the African early anthropoids either emigrated from Asia or evolved their anthropoid traits in parallel with living anthropoids.<\/p>\n<h4 class=\"import-Normal\"><em>Eosimiids<\/em><\/h4>\n<p class=\"import-Normal\">First described in the 1990s, the eosimiids are best represented by <em>Eosimias <\/em>(see Figure 9.14; Figure 9.18). This tiny \u201cdawn monkey\u201d is known from relatively complete jaws with teeth, a few small fragments of the face, and some postcranial elements (Beard et al. 1994; Beard et al. 1996; Gebo et al. 2000). <em>Eosimias<\/em> (along with the other less-well-known genera in its family) bears some resemblance to tarsiers as well as anthropoids. Unfortunately, no good crania are known for this family, and the anatomy of, for example, the posterior orbital margin could be very revealing as to higher-level relationships.<\/p>\n<figure style=\"width: 550px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image16-1-1.jpg\" alt=\"Red-colored lower jaw of an animal.\" width=\"550\" height=\"232\" \/><figcaption class=\"wp-caption-text\">Figure 9.18: Cast of the right half of the mandible of Eosimias centennicus, type specimen. The white scale bar is 1 cm long. Credit: <a class=\"rId74\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Cast of the right half of the mandible of <\/a><a class=\"rId75\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\"><em>Eosimias centennicus <\/em><\/a><a class=\"rId76\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">(Figure 8.15),<\/a> type specimen, from K. D. Rose cast collection, photo by Jonathan M. G. Perry is under a <a class=\"rId77\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<h4 class=\"import-Normal\"><em>Amphipithecids<\/em><\/h4>\n<p class=\"import-Normal\">Amphipithecids are small- to medium-size primates (up to 10 kg; 22 lbs.). Most are from the Eocene Pondaung Formation in Myanmar (Early\u2013Middle Eocene), but one genus is known from Thailand. Some dental similarities with anthropoids were noted early on, such as deep jaws and wide basins that separate low molar cusps. The best known genera were <em>Pondaungia<\/em> and <em>Amphipithecus <\/em>(Ciochon and Gunnell 2002; see Figure 9.14). Another amphipithecid, <em>Siamopithecus<\/em> from Thailand, has very rounded molars and was probably a seed-eater (Figure 9.19). In addition to teeth and jaws, some cranial fragments, ankle material, and ends of postcranial bones have been found for <em>Pondaungia<\/em>. There are important resemblances between the postcranial bones of <em>Pondaungia<\/em> and those of adapoids, suggesting adapoid affinities for the amphipithecidae. This would imply that the resemblances with anthropoids in the teeth are convergent, based on similarities in diet (see Ciochon and Gunnell 2002). Unfortunately, the association between postcranial bones and teeth is not definite. With other primates in these faunas (including eosimiids), one cannot be certain that the postcranial bones belong with the teeth. Some researchers suggest that some bones belong to a sivaladapid (or asiadapid) and others to an early anthropoid (Beard et al. 2007; Marivaux et al. 2003). Additional well-associated material of amphipithecids would help to clear up this uncertainty.<\/p>\n<figure style=\"width: 505px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image15-2.jpg\" alt=\"Four casts of jawbone fragments with teeth.\" width=\"505\" height=\"368\" \/><figcaption class=\"wp-caption-text\">Figure 9.19: Casts of representative amphipithecid material. A. Pondaungia cotteri right lower jaw fragment with m2 and m3. B. Siamopithecus eocaenus right upper jaw fragment with p4-m3. C. S. eocaenus right lower jaw fragment with partial m1, m2, and m3 in lateral view. D. Same as in C but occlusal view. White scale bars are 1 cm long. Credit: <a class=\"rId79\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Casts of representative amphipithecid material (Figure 8.16)l<\/a> from K. D. Rose cast collection, photo by Jonathan M. G. Perry is under a <a class=\"rId80\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Platyrrhine Dispersal to South America<\/strong><\/h3>\n<p class=\"import-Normal\">Today there is an impressive diversity of primates in South and Central America. These are considered to be part of a single clade, the Platyrrhini. Primates colonized South America sometime in the Eocene from an African source. In the first half of the 20th century, the source of platyrrhines was a matter of major debate among paleontologists, with some favoring a North American origin (e.g., Simpson 1940).<\/p>\n<p class=\"import-Normal\">Part of the reason for this debate is that South America was an island in the Eocene. Primates needed to cross open ocean to get there from either North America or Africa, although the distance from the former was shorter. Morphology yields clues to platyrrhine origins. The first known primates in South America have more in common morphologically with African primates than with North American ones. At the time, anthropoids were popping up in North Africa, whereas the only euprimates in North America were adapoids and omomyoids. Despite lacking a bony ear tube, early platyrrhines shared a great deal with other anthropoids, including full postorbital closure and fusion of the mandibular symphysis.<\/p>\n<p class=\"import-Normal\">The means by which a population of small North African primates managed to disperse across the Atlantic and survive to colonize South America remains a mystery. The most plausible scenario is one of rafting. That is, primates must have been trapped on vegetation that was blown out to sea by a storm. The vegetation then became a sort of life raft, which eventually landed ashore, dumping its passengers in South America. Rodents probably arrived in South America in the same way (Antoine et al. 2012).<\/p>\n<p class=\"import-Normal\">Once ashore, platyrrhines must have crossed South America fairly rapidly because the earliest-known primates from that continent are from Peru (Bond et al. 2015). Soon after that, platyrrhines were in Bolivia, namely <em>Branisella<\/em>. By the Miocene, platyrrhines were living in extreme southern Argentina and were exploiting a variety of feeding niches. The Early Miocene platyrrhines were all somewhat plesiomorphic in their morphology, but some features that likely arose by ecological convergence suggest (to some) relationships with extant platyrrhine families. This has led to a lively debate about the pattern of primate evolution in South America (Kay 2015; Kay and Fleagle 2010; Rosenberger 2010). By the Middle Miocene, clear representatives of modern families were present in a diverse fauna from La Venta, Colombia (Wheeler 2010). The Plio-Pleistocene saw the emergence of giant platyrrhines as well as several taxa of platyrrhines living on Caribbean islands (Cooke et al. 2016).<\/p>\n<p class=\"import-Normal\">The story of platyrrhines seems to be one of amazing sweepstakes dispersal, followed by rapid diversification and widespread geographic colonization of much of South America. After that, dramatic extinctions resulted in the current, much-smaller geographic distribution of platyrrhines. These extinctions were probably caused by changing climates, leading to the contraction of forests. Platyrrhines dispersed to the Caribbean and to Central America, with subsequent extinctions in those regions that might have been related to interactions with humans. Unlike anthropoids of Africa and Asia, platyrrhines do not seem to have evolved any primarily terrestrial forms and so have always been highly dependent on forests.<\/p>\n<div class=\"textbox\">\n<h2 class=\"import-Normal\">Special Topic: Jonathan Perry and Primates of the Extreme South<\/h2>\n<p class=\"import-Normal\">Many primates are very vulnerable to ecological disturbance because they are heavily dependent on fruit to eat and trees to live in. This is one reason why so many primates are endangered today and why many of them went extinct due to climatic and vegetational changes in the past. I (Jonathan Perry) have conducted paleontological research focusing on primates that lived on the edge of their geographic distribution. This research has taken me to extreme environments in the Americas: southern Patagonia, the Canadian prairies, western Wyoming, and the badlands of eastern Oregon.<\/p>\n<p class=\"import-Normal\">Santa Cruz Province in Argentina is as far south as primates have ever lived. The Santa Cruz fauna of the Miocene has yielded a moderate diversity of platyrrhines, each with slightly different dietary adaptations. These include <em>Homunculus<\/em>, first described by Florentino Ameghino in 1891 (Figure 9.20). Recent fieldwork by my colleagues and I in Argentina has revealed several skulls of <em>Homunculus <\/em>as well as many parts of the skeleton (Kay et al. 2012). The emerging profile of this extinct primate is one of a dedicated arboreal quadruped that fed on fruits and leaves. Many of the foods eaten by <em>Homunculus<\/em> must have been very tough and were probably covered and impregnated with grit; we suspect this because the cheek teeth are very worn down, even in young individuals, and because the molar tooth roots were very large, presumably to resist strong bite forces (Perry et al. 2010, 2014).<\/p>\n<figure style=\"width: 497px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image9-2.jpg\" alt=\"An animal skull, a partial skull, and a fossil jaw with teeth.\" width=\"497\" height=\"634\" \/><figcaption class=\"wp-caption-text\">Figure 9.20: Representative specimens of Homunculus patagonicus. A. Adult cranium in lateral view. B. Adult cranium surface reconstructed from microCT scans, with the teeth segmented out. C. Juvenile cranium. White scale bars are 1cm long. Credit: <a class=\"rId82\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Representative specimens of <\/a><a class=\"rId83\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\"><em>Homunculus patagonicus <\/em><\/a><a class=\"rId84\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">(Figure 8.17)<\/a> photo by Jonathan M. G. Perry is under a <a class=\"rId85\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">I began working in Argentina while a graduate student at Duke University. I participated as a field assistant in a team led by my Ph.D. advisor, Richard F. Kay, and Argentine colleagues Sergio F. Vizca\u00edno and M. Susana Bargo. Most of the localities examined belong to a suite of beach sites known since the 1800s and visited by many field parties from various museums in the early 1900s. Since 2003, our international team of paleontologists from the U.S. and Argentina has visited these localities every single year (Figure 9.21). Over time, new fossils and new students have led to new projects and new approaches, including the use of microcomputed tomography (microCT) to visualize and analyze internal structures of the skeleton.<\/p>\n<figure style=\"width: 491px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image23.jpg\" alt=\"Sandy rocky coastline. People digging on a grassy hillside.\" width=\"491\" height=\"561\" \/><figcaption class=\"wp-caption-text\">Figure 9.21: Field localities in Argentina and Canada. A. Ca\u00f1adon Palos locality, coastal Santa Cruz Province, Argentina. B. Swift Current Creek locality, southwest Saskatchewan, Canada. Credits: A. <a class=\"rId87\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Ca\u00f1adon Palos Field Locality in Argentina<\/a> by Jonathan M. G. Perry is under a <a class=\"rId88\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. B. <a class=\"rId89\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Swift Current Creek locality, Saskatchewan, Canada<\/a> by Jonathan M. G. Perry is under a <a class=\"rId90\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<\/div>\n<h2 class=\"import-Normal\">Planet of Apes<\/h2>\n<h3 class=\"import-Normal\"><strong>Geologic Activity and Climate Change in the Miocene<\/strong><\/h3>\n<p class=\"import-Normal\">The Miocene Epoch was a time of mammalian diversification and extinction, global climate change, and ecological turnover. In the Miocene, there was an initial warming trend across the globe with the expansion of subtropical forests, followed by widespread cooling and drying with the retreat of tropical forests and replacement with more open woodlands and eventually grasslands. It was also a time of major geologic activity. On one side of the globe, South America experienced the rise of the Andes Mountains. On the other side, the Indian subcontinent collided with mainland Asia, resulting in the rise of the Himalayan Mountains. In Africa, volcanic activity promoted the development of the East African Rift System. Critical to the story of ape evolution was the exposure of an intercontinental landbridge between East Africa and Eurasia, permitting a true planet of apes (Figure 9.22).<\/p>\n<figure id=\"attachment_277\" aria-describedby=\"caption-attachment-277\" style=\"width: 580px\" class=\"wp-caption aligncenter\"><img class=\"wp-image-273\" src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image21-3-e1691792198797.png\" alt=\"Map of world with gray continents.\" width=\"580\" height=\"335\" \/><figcaption id=\"caption-attachment-277\" class=\"wp-caption-text\">Figure 9.22: Map of the world in the Miocene, highlighting fossil ape localities across Africa, southern Europe, and southern Asia. Credit: <a class=\"rId92\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-10\/\">Miocene Map with Fossil Ape Localities (Figure 8.19)<\/a> original to <a class=\"rId93\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a class=\"rId94\" href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a class=\"rId95\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Localities based on Fleagle 2013, 311.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Geographic Distribution: Africa, Asia, Europe<\/strong><\/h3>\n<p class=\"import-Normal\">The world of the Miocene had tremendous ape diversity compared to today. The earliest records of fossil apes are from Early Miocene deposits in Africa. However, something dramatic happened around 16 million years ago. With the closure of the ancient Tethys Sea, the subsequent exposure of the <em>Gomphotherium<\/em> Landbridge, and a period of global warming, the Middle\u2013Late Miocene saw waves of emigration of mammals (including primates) out of Africa and into Eurasia, with evidence of later African re-entry for some (Harrison 2010). Some of the mammals that dispersed from Africa to Eurasia and back were apes. Though most of these early apes left no modern descendants, some of them gave rise to the ancestors of modern apes\u2014including <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_410_800\">hominins<\/a><\/strong> (Figure 9.23).<\/p>\n<figure style=\"width: 560px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image20-1.jpg\" alt=\"Miocene apes set against a geologic time scale.\" width=\"560\" height=\"796\" \/><figcaption class=\"wp-caption-text\">Figure 9.23: Representative Miocene apes set against a geologic time scale. Credit: <a href=\"https:\/\/www.pnas.org\/content\/108\/14\/5554\">Range chart for Miocene hominoids of Western Eurasia (Figure 3)<\/a> by Isaac Casanovas-Vilar, David M. Alba, Miguel Garc\u00e9s, Josep M. Robles, and Salvador Moy\u00e0-Sol\u00e0. 2011. <a href=\"https:\/\/www.pnas.org\/about\/rights-permissions\">Proceedings of the National Academy of Sciences of the United States of America<\/a> 108 (14): 5554-5559. Copyright (2011) National Academy of Sciences. Image <a href=\"https:\/\/www.pnas.org\/about\/rights-permissions\">is used for non-commercial and educational purposes as outlined by PNAS.<\/a><\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>Where Are the Monkeys? Diversity in the Miocene<\/strong><\/h3>\n<p class=\"import-Normal\">Whereas the Oligocene deposits in the Fayum of Egypt have yielded the earliest-known catarrhine fossils, the Miocene demonstrates some diversification of Cercopithecoidea. However, compared to the numerous and diverse Miocene apes (see below), monkeys of the Miocene are very rare and restricted to a single extinct family, the Victoriapithecidae (Figure 9.24). This family contains the earliest definite cercopithecoids. These monkeys are found from northern and eastern Africa between 20 million and 12.5 million years ago (Miller et al. 2009). The best known early African monkey is <em>Victoriapithecus <\/em>(Figure 9.25), a small-bodied (approximately 7 kg; 15 lbs.), small-brained monkey. <strong>Bilophodonty<\/strong>, known to be a hallmark of molar teeth of modern cercopithecoid, was present to some extent in Victoriapithecids. <em>Victoriapithecus<\/em> has been reconstructed as being more frugivorous and perhaps spent more time on the ground (terrestrial locomotion) than in the trees (arboreal locomotion; Blue et al. 2006). The two major groups of cercopithecoids today are cercopithecines and colobines. The earliest records demonstrating clear members of each of these two groups are at the end of the Miocene. Examples include the early colobine <em>Microcolobus<\/em> from Kenya and the early cercopithecine <em>Pliopapio<\/em> from Ethiopia.<\/p>\n<div style=\"text-align: left\">\n<table class=\"aligncenter\" style=\"width: 473.25pt;height: 349px\">\n<caption>Figure 9.24: Some families of later anthropoids with example genera and traits: a table. Credit: Late anthropoids table original to Explorations: An Open Invitation to Biological Anthropology (2nd ed.) by Jonathan M. G. Perry and Stephanie L. Canington is under a <a class=\"rId100\" href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>. Content derived from Fleagle 2013.<\/caption>\n<thead>\n<tr style=\"height: 25pt\">\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 60px;width: 119.35px\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Family<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 60px;width: 103.417px\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Genera<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 60px;width: 191.65px\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Morphology<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 60px;width: 67.3667px\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Location<\/strong><\/p>\n<p>&nbsp;<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 60px;width: 73.2167px\">\n<p class=\"import-Normal\" style=\"text-align: center\"><strong>Age<\/strong><sup><strong>1<\/strong><\/sup><\/p>\n<p>&nbsp;<\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"Table4-R\" style=\"height: 18pt\">\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 77px;width: 119.35px\">\n<p class=\"import-Normal\">Victoriapithecidae<sup>2<\/sup><\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 77px;width: 103.417px\">\n<p class=\"import-Normal\"><em>Victoriapithecus<\/em><\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 77px;width: 191.65px\">\n<p class=\"import-Normal\">Long, sloping face. Round, narrowly spaced orbits. Deep cheek bones. Well-developed sagittal crest.<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 77px;width: 67.3667px\">\n<p class=\"import-Normal\">Africa<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 77px;width: 73.2167px\">\n<p class=\"import-Normal\">Early to Middle Miocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table4-R\" style=\"height: 16pt\">\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 61px;width: 119.35px\">\n<p class=\"import-Normal\">Proconsulidae<sup>3<\/sup><\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 61px;width: 103.417px\">\n<p class=\"import-Normal\"><em>Proconsul<\/em><\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 61px;width: 191.65px\">\n<p class=\"import-Normal\">Short face. Generalized dentition. Arboreal quadruped. Probably tailless.<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 61px;width: 67.3667px\">\n<p class=\"import-Normal\">Africa and Arabia<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 61px;width: 73.2167px\">\n<p class=\"import-Normal\">Early to Middle Miocene<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table4-R\" style=\"height: 16pt\">\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 46px;width: 119.35px\">\n<p class=\"import-Normal\">Pongidae<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 46px;width: 103.417px\">\n<p class=\"import-Normal\"><em>Gigantopithecus<\/em><\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 46px;width: 191.65px\">\n<p class=\"import-Normal\">Largest primate ever. Deep jaws and low rounded molars.<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 46px;width: 67.3667px\">\n<p class=\"import-Normal\">Asia<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"vertical-align: middle;padding: 0pt 5.4pt;border: 0.5pt solid #000000;height: 46px;width: 73.2167px\">\n<p class=\"import-Normal\">Miocene to Present<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table4-R\" style=\"height: 1pt\">\n<td class=\"Table4-C\" style=\"border-color: #000000;border-style: solid none none;border-width: 0.5pt 0pt 0pt;padding: 0pt 5.4pt;height: 90px;width: 526.983px\" colspan=\"4\">\n<p class=\"import-Normal\"><sup>1<\/sup> Derived from Fleagle 2013.<\/p>\n<p class=\"import-Normal\"><sup>2<\/sup> See Benefit and McCrossin 1997 and Fleagle 2013.<\/p>\n<p class=\"import-Normal\"><sup>3<\/sup> See Begun 2007.<\/p>\n<\/td>\n<td class=\"Table4-C\" style=\"border-color: #000000;border-style: solid none none;border-width: 0.5pt 0pt 0pt;padding: 0pt 5.4pt;height: 90px;width: 73.2167px\">\n<p class=\"import-Normal\">\n<\/td>\n<\/tr>\n<tr style=\"height: 15px\">\n<td style=\"height: 15px;width: 121.283px\"><\/td>\n<td style=\"height: 15px;width: 105.35px\"><\/td>\n<td style=\"height: 15px;width: 193.583px\"><\/td>\n<td style=\"height: 15px;width: 69.3px\"><\/td>\n<td style=\"height: 15px;width: 74.65px\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h3><\/h3>\n<h3><\/h3>\n<h3><\/h3>\n<h3 class=\"import-Normal\"><strong>The Story of Us, the Apes<\/strong><\/h3>\n<h4 class=\"import-Normal\"><em>African Ape Diversity\u00a0<\/em><\/h4>\n<p class=\"import-Normal\">The Early Miocene of Africa has yielded around 14 genera of early apes (Begun 2003). Many of these taxa have been reconstructed as frugivorous arboreal quadrupeds (Kay 1977). One of the best studied of these genera is the East African <em>Proconsul<\/em> (Family Proconsulidae; see Figure 9.24). Several species have been described, with body mass reconstructions ranging from 17 to 50 kg (approximately 37\u2013110 lbs.). A paleoenvironmental study reconstructed the habitat of <em>Proconsul <\/em>to be a dense, closed-canopy tropical forest (Michel et al. 2014). No caudal vertebrae (tail bones) have been found in direct association with <em>Proconsul <\/em>postcrania, and the morphology of the sacrum is consistent with <em>Proconsul<\/em> lacking a tail (Russo 2016; Ward et al. 1991).<\/p>\n<p class=\"import-Normal\">Overall, the African ape fossil record in the Late Miocene is sparse, with seven fossil localities dating between eleven and five million years ago (Pickford et al. 2009). Nevertheless, most species of great apes live in Africa today. Where did the progenitors of modern African apes arise? Did they evolve in Africa or somewhere else? The paucity of apes in the Late Miocene of Africa stands in contrast to the situation in Eurasia. There, ape diversity was high. Furthermore, several Eurasian ape fossils show morphological affinities with modern hominoids (apes). Because of this, some paleoanthropologists suggest that the ancestors of modern African great apes recolonized Africa from Eurasia toward the end of the Miocene (Begun 2002). However, discoveries of Late Miocene hominoids like the Kenyan <em>Nakalipithecus<\/em> (9.9 million to 9.8 million years ago), the Ethiopian <em>Chororapithecus<\/em> (10.7 million to 10.1 million years ago), and the late-Middle Miocene Namibian <em>Otavipithecus<\/em> (13 million to 12 million years ago) fuel an alternative hypothesis\u2014namely that African hominoid diversity was maintained throughout the Miocene and that one of these taxa might, in fact, be the last common ancestor of extant African apes (Kunimatsu et al. 2007; Mocke et al. 2002). The previously underappreciated diversity of Late Miocene apes in Africa might be due to poor sampling of the fossil record in Africa.<\/p>\n<h4 class=\"import-Normal\"><em>Eurasian Ape Diversity<\/em><\/h4>\n<p class=\"import-Normal\">With the establishment of the <em>Gomphotherium<\/em> Landbridge (a result of the closure of the Eastern Mediterranean seaway; R\u00f6gl 1999), the Middle Miocene was an exciting time for hominoid radiations outside of Africa (see Figure 9.23). Eurasian hominoid species exploited their environments in many different ways in the Miocene. Food exploitation ranged from soft-fruit feeding in some taxa to hard-object feeding in others, in part owing to seasonal fluctuations and the necessary adoptions of fallback foods (DeMiguel et al. 2014). For example, the molars of <em>Oreopithecus bambolii<\/em> (Family Hominidae) have relatively long lower-molar shearing crests, suggesting that this hominoid was very folivorous (Ungar and Kay 1995). Associated with variation in diet, there is great variation in the degree to which cranial features (e.g., zygomatic bone or supraorbital tori) are developed across the many taxa (Cameron 1997); however, Middle Miocene fossils tend to exhibit relatively thick molar enamel and relatively robust jaws (Andrews and Martin 1991).<\/p>\n<p class=\"import-Normal\">In Spain, the cranium with upper dentition, part of a mandible, and partial skeleton of <em>Pliobates <\/em>(Family Pliobatidae), a small-bodied ape (4\u20135 kg; 9\u201311 lbs.), was discovered in deposits dating to 11.6 million years ago (Alba et al. 2015). It is believed to be a frugivore with a relative brain size that overlaps with modern cercopithecoids. The fossilized postcrania of <em>Pliobates<\/em> suggest that this ape might have had a unique style of locomotion, including the tendency to walk across the branches of trees with its palms facing downward and flexible wrists that permitted rotation of the forearm during climbing. However, the anatomy of the distal humerus differs from those of living apes in ways that suggest that <em>Pliobates<\/em> was less efficient at stabilizing its elbow while suspended (Benefit and McCrossin 2015). Two other recently described apes from Spain, <em>Pierolapithecus <\/em>and <em>Anoiapithecus<\/em>, are known from relatively complete skeletons. <em>Pierolapithecus<\/em> had a very projecting face and thick molar enamel as well as some skeletal features that suggest (albeit controversially) a less suspensory locomotor style than in extant apes (Moy\u00e0-Sol\u00e0 et al. 2004). In contrast to <em>Pierolapithecus<\/em>, the slightly younger <em>Anoiapithecus<\/em> has a very flat face (Moy\u00e0-Sol\u00e0 et al. 2009).<\/p>\n<p class=\"import-Normal\">Postcranial evidence for suspensory or well-developed orthograde behaviors in apes does not appear until the Late Miocene of Europe. Primary evidence supporting these specialized locomotor modes includes the relatively short lumbar vertebrae of <em>Oreopithecus <\/em>(Figure 9.26) and <em>Dryopithecus<\/em> (Maclatchy 2004). Further, fossil material of the lower torso of <em>O. bambolii <\/em>(which dates to the <em>Pan<\/em>-hominin divergence) conveys a higher degree of flexion-extension abilities in the lumbar region (lower back) than what is possible in extant apes. Additionally, the hindlimb of <em>O. bambolii <\/em>is suggested to have supported powerful hip adduction during climbing (Hammond et al. 2020). The Late Miocene saw the extinction of most of the Eurasian hominoids in an event referred to as the Vallesian Crisis (Agust\u00ed et al. 2003). Among the latest surviving hominoid taxa in Eurasia were <em>Oreopithecus<\/em> and <em>Gigantopithecus<\/em>, the latter of which held out until the Pleistocene in Asia and was probably even sympatric with <em>Homo erectus<\/em> (Cachel 2015).<\/p>\n<figure style=\"width: 436px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image8-2-1.jpg\" alt=\"Posterior view of ancient ape skeleton.\" width=\"436\" height=\"775\" \/><figcaption class=\"wp-caption-text\">Figure 9.26: Skeleton of Oreopithecus bambolii. Credit: <a class=\"rId107\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Oreopithecus_bambolii_1.JPG\">Oreopithecus bambolii 1<\/a> by <a class=\"rId108\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Ghedoghedo\">Ghedoghedo<\/a> is under a <a class=\"rId109\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>.<\/figcaption><\/figure>\n<h3 class=\"import-Normal\"><strong>The Origins of Extant Apes<\/strong><\/h3>\n<p class=\"import-Normal\">The fossil record of the extant apes is somewhat underwhelming: it ranges from being practically nonexistent for some taxa (e.g., chimpanzees) to being a little better for others (e.g., humans). There are many possible reasons for these differences in fossil abundance, and many are associated with the environmental conditions necessary for the fossilization of bones. One way to understand the evolution of extant apes that is not so dependent on the fossil record is via molecular evolutionary analyses. This can include counting up the differences in the genetic sequence between two closely related species to estimate the amount of time since these species shared a common ancestor. This is called a molecular clock, and it is often calibrated using fossils of known absolute age that stand in for the last common ancestor of a particular clade. Molecular clock estimates have placed the Hylobatidae and Hominidae split between 19.7 million and 24.1 million years ago, the African ape and Asian ape split between 15.7 million and 19.3 million years ago, and the split of Hylobatidae into its current genera between 6.4 million and 8 million years ago (Israfil et al. 2011).<\/p>\n<h4 class=\"import-Normal\"><em>Small Ape Origins and Fossils<\/em><\/h4>\n<p class=\"import-Normal\">Unfortunately, the fossil record for the small (formerly \u201clesser\u201d) apes is meager, particularly in Miocene deposits. One possible early hylobatid is <em>Laccopithecus robustus<\/em>, a Late Miocene catarrhine from China (Harrison 2016). Although it does share some characteristics with modern gibbons and siamangs (including an overall small body size and a short face), <em>Laccopithecus<\/em> most likely represents a plesiomorphic stem catarrhine and is therefore distantly related to extant apes (Jablonski and Chaplin 2009). A more likely candidate for the hylobatid stem is another Late Miocene taxon from China, <em>Yuanmoupithecus xiaoyuan<\/em>. Interpretation of its phylogenetic standing, however, is complicated by contradicting dental features\u2014some of them quite plesiomorphic\u2014which some believe best place <em>Yuanmoupithecus<\/em> as a stem hylobatid (Harrison 2016). Recently, a Middle Miocene Indian fossil ape, <em>Kapi ramnagarensis<\/em>, has extended the fossil record of small apes by approximately five million years. Its teeth are suggestive of a shift to a more frugivorous diet and it is likely a stem hylobatid (Gilbert et al. 2020). The history of Hylobatidae becomes clearer in the Pleistocene, with fossils representing extant genera.<\/p>\n<h4 class=\"import-Normal\"><em>Great Ape Origins and Fossils<\/em><\/h4>\n<p class=\"import-Normal\">The most extensive fossil record of a modern great ape is that of our own genus, <em>Homo<\/em>. However, the evolutionary history of the Asian great ape, the orangutan (<em>Pongo<\/em>), is becoming clearer. Today, orangutans are found only on the islands of Borneo and Sumatra. However, Pleistocene-aged teeth, attributed to <em>Pongo<\/em>, have been found in Cambodia, China, Laos, Peninsular Malaysia, and Vietnam\u2014demonstrating the vastness of the orangutan\u2019s previous range (Ibrahim et al. 2013; Wang et al. 2014). <em>Sivapithecus <\/em>from the Miocene of India and Pakistan is represented by many specimens, including parts of the face. <em>Sivapithecus<\/em> is very similar to <em>Pongo<\/em>, especially in the face, and it probably is closely related to ancestral orangutans (Pilbeam 1982). Originally, jaws and teeth belonging to the former genus <em>Ramapithecus<\/em> were thought to be important in the origin of humans (Simons 1961), but now these are recognized as specimens of <em>Sivapithecus<\/em> (Kelley 2002). Postcranial bones of <em>Sivapithecus<\/em>, however, suggest a more generalized locomotor mode\u2014including terrestrial locomotion\u2014than seen in <em>Pongo <\/em>(Pilbeam et al. 1990). Stable carbon and oxygen isotope data from dental enamel have reconstructed the paleoecological space of <em>Sivapithecus <\/em>(as well as the contemporaneous Late Miocene pongine <em>Khoratpithecus<\/em>) within the canopies of forested habitats (Habinger et al. 2022).<\/p>\n<p class=\"import-Normal\">A probable close relative of <em>Sivapithecus <\/em>is the amazing <em>Gigantopithecus<\/em> (see Figure 9.24). Known only from teeth and jaws from China and India (e.g., Figure 9.27), this ape probably weighed as much as 270 kg (595 lbs.) and was likely the largest primate ever (Bocherens et al. 2017). Because of unique features of its teeth (including molarized premolars and patterns of wear) and its massive size, it has been reconstructed as a bamboo specialist, somewhat like the modern panda. Small silica particles (phytoliths) from grasses have been found stuck to the molars of <em>Gigantopithecus<\/em> (Ciochon et al. 1990). Recent studies evaluating the carbon isotope composition of the enamel sampled from <em>Gigantopithecus<\/em> teeth suggest that this ape exploited a wide range of vegetation, including fruits, leaves, roots, and bamboo (Bocherens et al. 2017). Its face is reminiscent of that of modern orangutans and it might belong in the same family, Pongidae (Kelley 2002).<\/p>\n<figure style=\"width: 488px\" class=\"wp-caption aligncenter\"><img src=\"http:\/\/opentextbooks.concordia.ca\/wp-content\/uploads\/sites\/71\/2025\/07\/image12.jpg\" alt=\"Superior view of mandible and teeth.\" width=\"488\" height=\"533\" \/><figcaption class=\"wp-caption-text\">Figure 9.27: Cast of the mandible of Gigantopithecus blacki. Credit: <a class=\"rId111\" href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Gigantopithecus%20blacki%20mandible%20010112.jpg\">Gigantopithecus blacki mandible 010112<\/a> by <a class=\"rId112\" href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Wilson44691\">Wilson44691<\/a> is under a <a class=\"rId113\" href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/legalcode\">CC BY-SA 3.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">In Africa, the first fossil to be confidently attributed to <em>Pan<\/em>, and known to be the earliest evidence of a chimpanzee, was described based on teeth found in Middle Pleistocene deposits in the Eastern Rift Valley of Kenya (McBrearty and Jablonski 2005). Paleoenvironmental reconstructions of this locality suggest that this early chimpanzee was living in close proximity to early <em>Homo<\/em> in a closed-canopy wooded habitat. Similarly, fossil teeth and mandibular remains attributed to two species of Middle-Late Miocene apes\u2014<em>Chororapithecus abyssinicus<\/em> (from Ethiopia; Suwa et al. 2007) and <em>Nakalipithecus nakayamai<\/em> (from Kenya; Kunimatsu et al. 2007)\u2014have been suggested as basal members of the gorilla clade.<\/p>\n<p class=\"import-Normal\">While the deposits of Eastern Africa have yielded a profound record of our fossil hominin ancestors, the continent\u2019s rainforests remain a \u201cpalaeontological desert\u201d (Rosas et al. 2022). Clearly, more work is needed to fill in the large gaps in the fossil record of the nonhuman great apes. The twentieth century witnessed the discovery of many hominin fossils in East Africa, which have been critical for improving our understanding of human evolution. While twenty-first-century conservationists fight to prevent the extinction of the living great apes, perhaps efforts by twenty-first-century paleoanthropologists will yield the evolutionary story of these, our closest relatives.<\/p>\n<div class=\"textbox shaded\">\n<h2>Summary<\/h2>\n<p>While there are large gaps in the fossil records linking primates to early hominins, evolutionary trends make it clear that humans are one branch of the broader primate family tree. In this chapter we go over the major development that characterize primate evolution: enhanced vision, grasping hands and feet, greater reliance on social behavior, and increased brain complexity. It is these traits which distinguish primates from other mammals and furthermore, help define major subsections within the primate class, such as strepsirrhines, haplorhines, monkeys, apes, and ultimately hominins.<\/p>\n<p>Within this chapter, we also examine how anthropologists reconstruct these evolutionary relationships. Fossil evidence has provided key information about when and where different primates lived, while genetic data such as skeletal features allow researchers to understand how extinct species moved, ate, and interacted with their environments. Just as crucial are the influences of Earth\u2019s changing environments: continental drift, glacial cycles, and long-term climate shifts have repeatedly reshaped habitats, driving both extinctions and the emergence of new adaptive forms, including the emergence of our own human lineage.<\/p>\n<h2 class=\"import-Normal\">Review Questions<strong><br \/>\n<\/strong><\/h2>\n<ul>\n<li>Compare three major hypotheses about primate origins, making reference to each one\u2019s key ecological reason for primate uniqueness.<\/li>\n<li>Explain how changes in temperature, rainfall, and vegetation led to major changes in primate biogeography over the Early Tertiary.<\/li>\n<li>List some euprimate features that plesiadapiforms have and some that they lack.<\/li>\n<li>Contrast adapoids and omomyoids in terms of life habits.<\/li>\n<li>Describe one piece of evidence for each of the adapoid, omomyoid, and tarsier origin hypotheses for anthropoids.<\/li>\n<li>Discuss the biogeography of the origins of African great apes and orangutans using examples from the Miocene ape fossil record.<\/li>\n<\/ul>\n<\/div>\n<h2 class=\"import-Normal\">Key Terms<strong><br \/>\n<\/strong><\/h2>\n<p class=\"import-Normal\"><strong>Adapoidea<\/strong>: Order: Primates. One of the earliest groups of euprimates (true primates; earliest records from the early Eocene).<\/p>\n<p class=\"import-Normal\"><strong>A<\/strong><strong>daptive radiations<\/strong>: Rapid diversifications of single lineages into many species which may present unique morphological features in response to different ecological settings.<\/p>\n<p class=\"import-Normal\"><strong>Ancestral traits<\/strong>: Features that were inherited from a common ancestor and which remain (largely) unchanged.<\/p>\n<p class=\"import-Normal\"><strong>Anthropoids<\/strong>:Group containing monkeys and apes, including humans.<\/p>\n<p class=\"import-Normal\"><strong>Auditory bulla<\/strong>: The rounded bony floor of the middle ear cavity.<\/p>\n<p class=\"import-Normal\"><strong>Bilophodonty<\/strong>: Dental condition in which the cusps of molar teeth form ridges (or lophs) separated from each other by valleys (seen, e.g., in modern catarrhine monkeys).<\/p>\n<p class=\"import-Normal\"><strong>Catarrhines<\/strong>: Order: Primates; Suborder: Anthropoidea; Infraorder: Catarrhini. Group, with origins in Africa and Asia, that contains monkeys and apes, including humans.<\/p>\n<p class=\"import-Normal\"><strong>Clade<\/strong>:Group containing all of the descendants of a single ancestor. A portion of a phylogenetic tree represented as a bifurcation (node) in a lineage and all of the branches leading forward in time from that bifurcation.<\/p>\n<p class=\"import-Normal\"><strong>Convergent evolution<\/strong>: The independent evolution of a morphological feature in animals not closely related (e.g., wings in birds and bats).<\/p>\n<p class=\"import-Normal\"><strong>Crown<\/strong>: Smallest monophyletic group (clade) containing a specified set of extant taxa and all descendants of their last common ancestor.<\/p>\n<p class=\"import-Normal\"><strong>Diastema<\/strong>: Space between adjacent teeth.<\/p>\n<p class=\"import-Normal\"><strong>Diffuse coevolution<\/strong>: The ecological interaction between whole groups of species (e.g., primates) with whole groups of other species (e.g., fruiting trees).<\/p>\n<p class=\"import-Normal\"><strong>Ectotympanic<\/strong>: Bony ring or tube that holds the tympanic membrane (eardrum).<\/p>\n<p class=\"import-Normal\"><strong>Euprimates<\/strong>: Order: Primates. True primates or primates of modern aspect.<\/p>\n<p class=\"import-Normal\"><strong>Haplorhines<\/strong>: Group containing catarrhines, platyrrhines, and tarsiers.<\/p>\n<p class=\"import-Normal\"><strong>Hominins<\/strong>: Modern humans and any extinct relatives more closely related to us than to chimpanzees.<\/p>\n<p class=\"import-Normal\"><strong>Mandibular symphysis<\/strong>: Fibrocartilaginous joint between the left and right mandibular segments, located in the midline of the body.<\/p>\n<p class=\"import-Normal\"><strong>Omomyoidea<\/strong>: Order: Primates; Superfamily: Omomyoidea. One of the earliest groups of euprimates (true primates; earliest record in the early Eocene).<\/p>\n<p class=\"import-Normal\"><strong>Petrosal bone<\/strong>: The portion of the temporal bone that houses the inner ear apparatus.<\/p>\n<p class=\"import-Normal\"><strong>Plagiaulacoid<\/strong>: Dental condition where at least one of the lower cheek-teeth (molars or premolars) is a laterally compressed blade.<\/p>\n<p class=\"import-Normal\"><strong>Platyrrhines<\/strong>: Order: Primates; Suborder: Anthropoidea; Infraorder: Platyrrhini. Group containing monkeys found in the Americas.<\/p>\n<p class=\"import-Normal\"><strong>Plesiadapiforms<\/strong>: Order: Plesiadapiformes. Archaic primates or primate-like placental mammals (Early Paleocene\u2013Late Eocene).<\/p>\n<p class=\"import-Normal\"><strong>P<\/strong><strong>lesiomorphic<\/strong>: Having features that are shared by different groups which arose from a common ancestor.<\/p>\n<p class=\"import-Normal\"><strong>Stem<\/strong>: Taxa that are basal to a given crown group but are more closely related to the crown group than to the closest living sister taxon of the crown group.<\/p>\n<p class=\"import-Normal\"><strong>Strepsirrhines<\/strong>: Order: Primates; Suborder: Stresirrhini. Group containing lemurs, lorises, and galagos (does not include tarsiers).<\/p>\n<p class=\"import-Normal\"><strong>Toothcomb<\/strong>: Dental condition found in modern strepsirrhines in which the lower incisors and canines are laterally compressed and protrude forward at a nearly horizontal inclination. This structure is used in grooming.<\/p>\n<\/div>\n<div class=\"__UNKNOWN__\">\n<h2 class=\"import-Normal\">For Further Exploration<strong><br \/>\n<\/strong><\/h2>\n<p class=\"import-Normal\">Beard, Chris. 2004. <em>The Hunt for the Dawn Monkey: Unearthing the Origins of Monkeys, Apes, and Humans<\/em>. Berkeley: University of California Press.<\/p>\n<p class=\"import-Normal\">Begun, David R. 2010. \u201cMiocene Hominids and the Origins of the African Apes and Humans.\u201d <em>Annual Review of Anthropology<\/em> 39: 67\u201384.<\/p>\n<p class=\"import-Normal\">Fleagle, John G. 2013. <em>Primate Adaptation and Evolution.<\/em> Third edition. San Diego, CA: Academic Press.<\/p>\n<p class=\"import-Normal\">Gebo, Daniel L., ed. 1993. <em>Postcranial Adaptations in Nonhuman Primates<\/em>. Dekalb: Northern Illinois University Press.<\/p>\n<p class=\"import-Normal\">Godfrey, Laurie R., and William L. Jungers. 2002. \u201cQuaternary Fossil Lemurs.\u201d In <em>The Primate Fossil Record, <\/em>edited by Walter C. Hartwig, 97\u2013121. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Godinot, Marc. 2006. \u201cLemuriform Origins as Viewed from the Fossil Record.\u201d <em>Folia Primatologica<\/em> 77 (6): 446\u2013464.<\/p>\n<p class=\"import-Normal\">Kay, Richard F. 2018. \u201c100 Years of Primate Paleontology.\u201d <em>American Journal of Physical Anthropology<\/em> 165 (4): 652\u2013676.<\/p>\n<p class=\"import-Normal\">Marivaux, Laurent. 2006. \u201cThe Eosimiid and Amphipithecid Primates (Anthropoidea) from the Oligocene of the Bugti Hills (Balochistan, Pakistan): New Insight into Early Higher Primate Evolution in South Asia.\u201d <em>Palaeovertebrata, Montpellier <\/em>34 (1\u20132): 29\u2013109.<\/p>\n<p class=\"import-Normal\">Martin, R. D. 1990. <em>Primate Origins and Evolution<\/em><em>: A <\/em><em>Phylogenetic Reconstruction<\/em>. Princeton: Princeton University Press.<\/p>\n<p class=\"import-Normal\">Rose, Kenneth D., Marc Godinot, and Thomas M. Bown. 1994. \u201cThe Early Radiation of Euprimates and the Initial Diversification of Omomyidae.\u201d In <em>Anthropoid Origins: The Fossil Evidence, <\/em>edited by John G. Fleagle and Richard F. Kay, 1\u201328. New York: Plenum Press.<\/p>\n<p class=\"import-Normal\">Ross, Callum F. 1999. \u201cHow to Carry Out Functional Morphology.\u201d <em>Evolutionary Anthropology<\/em> 7 (6): 217\u2013222.<\/p>\n<p class=\"import-Normal\">Seiffert, Erik R. 2012. \u201cEarly Primate Evolution in Afro-Arabia.\u201d Evolutionary Anthropology: Issues, News, and Reviews 21(6): 239\u2013253.<\/p>\n<p class=\"import-Normal\">Szalay, Frederic S., and Eric Delson. 1979. Evolutionary History of the Primates. New York: Academic Press.<\/p>\n<p class=\"import-Normal\">Ungar, Peter S. 2002. \u201cReconstructing the Diets of Fossil Primates.\u201d In <em>Reconstructing Behavior in the Primate Fossil Record<\/em>, edited by Joseph Plavcan, Richard F. Kay, William Jungers, and Carel P. van Schaik, 261\u2013296. New York: Kluwer Academic\/Plenum Publishers.<\/p>\n<h2 class=\"import-Normal\">References<\/h2>\n<p class=\"import-Normal\">Agust\u00ed, J., A. Sanz de Siria, and M. Garc\u00e9s M. 2003. \u201cExplaining the End of the Hominoid Experiment in Europe.\u201d <em>Journal of Human Evolution<\/em> 45 (2): 145\u2013153.<\/p>\n<p class=\"import-Normal\">Alba, David M., Sergio Alm\u00e9cija, Daniel DeMiguel, Josep Fortuny, Miriam P\u00e9rez de los R\u00edos, Marta Pina, Josep M. Robles, and Salvador Moy\u00e0-Sol\u00e0. 2015. \u201cMiocene Small-Bodied Ape from Eurasia Sheds Light on Hominoid Evolution.\u201d <em>Science<\/em> 350 (6260): aab2625.<\/p>\n<p class=\"import-Normal\">Andrews, Peter, and Lawrence Martin. 1991. \u201cHominoid Dietary Evolution.\u201d <em>Philosophical Transactions of the Royal Society of London B: Biological Sciences<\/em> 334 (1270): 199\u2013209.<\/p>\n<p class=\"import-Normal\">Antoine, Pierre-Oliver, Laurent Marivaux, Darren A. Croft, Guillaume Billet, Morgan Ganer\u00f8d, Carlos Jaramillo, Thomas Martin, et al. 2012. \u201cMiddle Eocene Rodents from Peruvian Amazonia Reveal the Pattern and Timing of Caviomorph Origins and Biogeography.\u201d <em>Proceedings of the Royal Society B: Biological Sciences<\/em> 279 (1732): 1319\u20131326.<\/p>\n<p class=\"import-Normal\">Beard, K. Christopher. 1990. \u201cGliding Behaviour and Palaeoecology of the Alleged Primate Family Paromomyidae (Mammalia, Dermoptera).\u201d <em>Nature<\/em> 345 (6273): 340\u2013341.<\/p>\n<p class=\"import-Normal\">Beard, K. Christopher. 2002. \u201cBasal Anthropoids.\u201d In <em>The Primate Fossil Record, <\/em>edited by William C. Hartwig, 133\u2013150. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Beard, K. Christopher, and R. D. E. MacPhee. 1994. \u201cCranial Anatomy of <em>Shoshonius<\/em> and the Antiquity of Anthropoidea.\u201d In <em>Anthropoid Origins: The Fossil Evidence<\/em>, edited by John G. Fleagle and Richard F. Kay, 55\u201398. New York: Plenum Press.<\/p>\n<p class=\"import-Normal\">Beard, K. Christopher, Laurent Marivaux, Soe Thura Tun, Aung Naing Soe, Yaowalak Chaimanee, Wanna Htoon, Bernard Marandat, Htun Htun Aung, and Jean-Jacques Jaeger. 2007. \u201cNew Sivaladapid Primates from the Eocene Pondaung Formation of Myanmar and the Anthropoid Status of Amphipithecidae.\u201d <em>Bulletin of Carnegie Museum of Natural History<\/em> 39: 67\u201376.<\/p>\n<p class=\"import-Normal\">Beard, K. Christopher, Tao Qi, Mary R. Dawson, Banyue Wang, and Chuankuei Li. 1994. \u201cA Diverse New Primate Fauna from Middle Eocene Fissure-Fillings in Southeastern China.\u201d <em>Nature<\/em> 368 (6472): 604\u2013609.<\/p>\n<p class=\"import-Normal\">Beard, K. Christopher, Yongsheng Tong, Mary R. Dawson, Jingwen Wang, and Xueshi Huang. 1996. \u201cEarliest Complete Dentition of an Anthropoid Primate from the Late Middle Eocene of Shanxi Province, China.\u201d <em>Science<\/em> 272 (5258): 82\u201385.<\/p>\n<p class=\"import-Normal\">Beecher, Robert M. 1983. \u201cEvolution of the Mandibular Symphysis in Notharctinae (Adapidae, Primates).\u201d <em>International Journal of Primatology<\/em> 4 (1): 99\u2013112.<\/p>\n<p class=\"import-Normal\">Begun, David R. 2002. \u201cEuropean Hominoids.\u201d In <em>The Primate Fossil Record<\/em>, edited by William C. Hartwig, 339\u2013368. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Begun, David R. 2003. \u201cPlanet of the Apes.\u201d <em>Scientific American<\/em> 289 (2): 74\u201383.<\/p>\n<p class=\"import-Normal\">Begun, David R. 2007. \u201cFossil Record of Miocene Hominoids.\u201d In <em>Handbook of Paleoanthropology<\/em>, edited by Winfried Henke and Ian Tattersall, 921\u2013977. New York: Springer.<\/p>\n<p class=\"import-Normal\">Benefit, Brenda R., and Monte L. McCrossin. 1997. \u201cEarliest Known Old World Monkey Skull.\u201d <em>Nature<\/em> 388 (6640): 368\u2013371.<\/p>\n<p class=\"import-Normal\">Benefit, Brenda R., and Monte L. McCrossin. 2015. \u201cA Window into Ape Evolution.\u201d <em>Science<\/em> 350 (6260): 515\u2013516.<\/p>\n<p class=\"import-Normal\">Bloch, Jonathan I., and David M. Boyer. 2002. \u201cGrasping Primate Origins.\u201d <em>Science<\/em> 298 (5598): 1606\u20131610.<\/p>\n<p class=\"import-Normal\">Bloch, Jonathan I., and David M. Boyer. 2007. \u201cNew Skeletons of Paleocene-Eocene Plesiadapiformes: A Diversity of Arboreal Positional Behaviors in Early Primates.\u201d In <em>Primate Origins: Adaptations and Evolution<\/em>, edited by Matthew J. Ravosa and Marian Dagosto, 535\u2013581. New York: Springer.<\/p>\n<p class=\"import-Normal\">Bloch, Jonathan I., and Mary T. Silcox. 2006. \u201cCranial Anatomy of the Paleocene Plesiadapiform <em>Carpolestes simpsoni<\/em> (Mammalia, Primates) Using Ultra High-Resolution X-ray Computed Tomography, and the Relationships of Plesiadapiforms to Euprimates.\u201d <em>Journal of Human Evolution<\/em>: 50 (1): 1\u201335.<\/p>\n<p class=\"import-Normal\">Blue, Kathleen T., Monte L. McCrossin, and Brenda R. Benefit. 2006. \u201cTerrestriality in a Middle Miocene Context: <em>Victoriapithecus<\/em> from Maboko, Kenya.\u201d In <em>Human Origins and Environmental Backgrounds<\/em>, edited by Hidemi Ishida, Russell Tuttle, Martin Pickford, Naomichi Ogihara, and Masato Nakatsukasa, 45\u201358. New York: Springer.<\/p>\n<p class=\"import-Normal\">Bocherens, Herv\u00e9, Friedemann Schrenk, Yaowalak Chaimanee, Ottmar Kullmer, Doris M\u00f6rike, Diana Pushkina, and Jean-Jacques Jaeger. 2017. \u201cFlexibility of Diet and Habitat in Pleistocene South Asian Mammals: Implications for the Fate of the Giant Fossil Ape <em>Gigantopithecus<\/em>.\u201d <em>Quaternary International<\/em> 434 (A): 148\u2013155.<\/p>\n<p class=\"import-Normal\">Bond, Mariano, Marcelo F. Tejedor, Kenneth E. Campbell Jr., Laura Chornogubsky, Nelson Novo, and Francisco Goin. 2015. \u201cEocene Primates of South America and the African Origins of New World Monkeys.\u201d <em>Nature<\/em> 520 (7548): 539\u2013541.<\/p>\n<p class=\"import-Normal\">Bown, T. M., and M. J. Kraus. 1988. \u201cGeology and Paleoenvironment of the Oligocene Jebel Qatrani Formation and Adjacent Rocks, Fayum Depression, Egypt.\u201d Professional Paper, 1452. Washington, DC: U.S. Geological Survey Professional Papers.<\/p>\n<p class=\"import-Normal\">Cachel, Susan. 2015.<em> Fossil Primates.<\/em> Vol. 69. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Cameron, David W. 1997. \u201cA Revised Systematic Scheme for the Eurasian Miocene Fossil Hominidae.\u201d <em>Journal of Human Evolution<\/em> 33 (4): 449\u2013477.<\/p>\n<p class=\"import-Normal\">Cartmill, Matt. 1972. \u201cArboreal Adaptations and the Origin of the Order Primates.\u201d In <em>The Functional and Evolutionary Biology of Primates<\/em>, edited by Russell Tuttle, 97\u2013122. Chicago: Aldine-Atherton.<\/p>\n<p class=\"import-Normal\">Cartmill, Matt. 1974. \u201cRethinking Primate Origins.\u201d <em>Science<\/em> 184 (4135): 436\u2013443.<\/p>\n<p class=\"import-Normal\">Cartmill, Matt, and Richard F. Kay. 1978. \u201cCraniodental Morphology, Tarsier Affinities, and Primate Suborders.\u201d In <em>Recent Advances in Primatology: Evolution,<\/em> edited by D. J. Chivers and K. A. Joysey, 205\u2013214. London: Academic Press.<\/p>\n<p class=\"import-Normal\">Casanovas-Vilar, Isaac, David M. Alba, Miguel Garc\u00e9s, Josep M. Robles, and Salvador Moy\u00e0-Sol\u00e0. 2011. \u201cUpdated Chronology for the Miocene Hominoid Radiation in Western Eurasia.\u201d <em>Proceedings of the National Academy of Sciences <\/em>108 (14): 5554-5559. https:\/\/doi:10.1073\/pnas.1018562108.<\/p>\n<p class=\"import-Normal\">Chaimanee, Yaowalak, Olivier Chavasseau, K. Christopher Beard, Aung Aung Kyaw, Aung Naing Soe, Chit Sein, Vincent Lazzari, et al. 2012. \u201cLate Middle Eocene Primate from Myanmar and the Initial Anthropoid Colonization of Africa.\u201d <em>Proceedings of the National Academy of Sciences<\/em> <em>of the United States of America <\/em>109 (26): 10293\u201310297.<\/p>\n<p class=\"import-Normal\">Chester, Stephen G. B., Jonathan I. Bloch, Doug M. Boyer, and William A. Clemens. 2015. \u201cOldest Known Euarchontan Tarsals and Affinities of Paleocene <em>Purgatorius<\/em> to Primates.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 112 (5): 1487\u20131492.<\/p>\n<p class=\"import-Normal\">Ciochon, Russell L., and Gregg F. Gunnell. 2002. \u201cChronology of Primate Discoveries in Myanmar: Influences on the Anthropoid Origins Debate.\u201d <em>Yearbook of Physical Anthropology<\/em> 45(S35): 2\u201335.<\/p>\n<p class=\"import-Normal\">Ciochon, R. L., D. R. Piperno, and R. G. Thompson. 1990. \u201cOpal Phytoliths Found on the Teeth of the Extinct Ape <em>Gigantopithecus blacki<\/em>: Implications for Paleodietary Studies.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 87 (20): 8120\u20138124.<\/p>\n<p class=\"import-Normal\">Clemens, William A. 2004. \u201c<em>Purgatorius<\/em> (Plesiadapiformes, Primates?, Mammalia), a Paleocene Immigrant into Northeastern Montana: Stratigraphic Occurrences and Incisor Proportions.\u201d <em>Bulletin of Carnegie Museum of Natural History<\/em> 36: 3\u201313.<\/p>\n<p class=\"import-Normal\">Cooke, Siobh\u00e1n B., Justin T. Gladman, Lauren B. Halenar, Zachary S. Klukkert, and Alfred L. Rosenberber. 2016. \u201cThe Paleobiology of the Recently Extinct Platyrrhines of Brazil and the Caribbean.\u201d In <em>Molecular Population Genetics, Evolutionary Biology and Biological Conservation of Neotropical Primates<\/em>, edited by Manuel Ruiz-Garcia and Joseph Mark Shostell, 41\u201389. New York: Nova Publishers.<\/p>\n<p class=\"import-Normal\">DeLeon, Valerie B., Timothy D. Smith, and Alfred L. Rosenberger. 2016. \u201cOntogeny of the Postorbital Region in Tarsiers and Other Primates.\u201d <em>Anatomical Record: Advances in Integrative Anatomy and Evolutionary Biology<\/em> 299 (12): 1631\u20131645.<\/p>\n<p class=\"import-Normal\">DeMiguel, Daniel, David M. Alba, and Salvador Moy\u00e0-Sol\u00e0. 2014. \u201cDietary Specialization during the Evolution of Western Eurasian Hominoids and the Extinction of European Great Apes.\u201d <em>PLoS ONE<\/em> 9 (5): e97442. https:\/\/doi.org\/10.1371\/journal.pone.0097442.<\/p>\n<p class=\"import-Normal\">Dunn, Rachel H., Kenneth D. Rose, Rajendra Rana, Kishore Kumar, Ashok Sahni, and Thierry Smith. 2016. \u201cNew Euprimate Postcrania from the Early Eocene of Gujarat, India, and the Strepsirrhine\u2013Haplorhine Divergence.\u201d <em>Journal of Human Evolution<\/em> 99: 25\u201351.<\/p>\n<p class=\"import-Normal\">Fleagle, John G. 2013. <em>Primate Adaptation and Evolution<\/em>, Third Edition. San Diego, CA: Academic Press.<\/p>\n<p class=\"import-Normal\">Fleagle, John G., and Richard F. Kay. 1994. <em>Anthropoid Origins<\/em>. New York: Plenum Press.<\/p>\n<p class=\"import-Normal\">Franzen, Jens Lorenz, Phillip D. Gingerich, J\u00f6rg Habersetzer, J\u00f8rn Hurum, von Wighart Koenigswald, and B. Holly Smith. 2009. \u201cComplete Primate Skeleton from the Middle Eocene of Messel in Germany: Morphology and Paleobiology.\u201d <em>PLoS ONE<\/em> 4 (5): e5723. doi:10.1371\/journal.pone.0005723.<\/p>\n<p class=\"import-Normal\">Gebo, Daniel L., Marian Dagosto, K. Christopher Beard, Tao Qi, and Jingwen Wang. 2000. \u201cThe Oldest Known Anthropoid Postcranial Fossils and the Early Evolution of Higher Primates.\u201d <em>Nature<\/em> 404 (6775): 276\u2013278.<\/p>\n<p class=\"import-Normal\">Gebo, Daniel L., and Elwyn L. Simons. 1987. \u201cMorphology and Locomotor Adaptations of the Foot in Early Oligocene Anthropoids.\u201d <em>American Journal of Physical Anthropology<\/em> 74 (1): 83\u2013101.<\/p>\n<p class=\"import-Normal\">Gilbert, Christopher C., Alejandra Ortiz, Kelsey D. Pugh, Christopher J. Campisano, Biren A. Patel, Ningthoujam Premjit Singh, John G. Fleagle, and Rajeev Patnaik. 2020. \u201cNew Middle Miocene Ape (Primates: Hylobatidae) from Ramnagar, India, Fills Major Gaps in the Hominoid Fossil Record.\u201d <em>Proceedings of the Royal Society B<\/em> 287(1934): 20201655.<\/p>\n<p class=\"import-Normal\">Gingerich, P. D. 1980. \u201cEocene Adapidae, Paleobiogeography, and the Origin of South American Platyrrhini.\u201d <em>In Evolutionary Biology of the New World Monkeys and Continental Drift, <\/em>edited by Russell L. Ciochon and A. Brunetto Chiarelli, 123\u2013138. New York: Plenum Press.<\/p>\n<p class=\"import-Normal\">Godfrey, Laurie R., and William L. Jungers. 2002. \u201cQuaternary Fossil Lemurs.\u201d In <em>The Primate Fossil Record<\/em>, edited by Walter C. Hartwig, 97\u2013121. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Godinot, Marc. 2006. \u201cLemuriform Origins as Viewed from the Fossil Record.\u201d <em>Folia Primatologica<\/em> 77 (6): 446\u2013464.<\/p>\n<p class=\"import-Normal\">Gregory, William K. 1920. \u201cOn the Structure and Relations of <em>Notharctus<\/em>, an American Eocene Primate.\u201d <em>Memoirs of the American Museum of Natural History<\/em> (N.S.) 3 (2).<\/p>\n<p class=\"import-Normal\">Gunnell, Gregg F., Doug M. Boyer, Anthony R. Friscia, Steven Heritage, Frederik Kyalo Manthi, Ellen R. Miller, Hesham M. Sallam, Nancy B. Simmons, Nancy J. Stevens, and Erik R. Seiffert. 2018. \u201cFossil Lemurs from Egypt and Kenya Suggest an African Origin for Madagascar\u2019s Aye-aye.\u201d <em>Nature Communications<\/em> 9 (3193): 1\u201312.<\/p>\n<p class=\"import-Normal\">Habinger, S. G., O. Chavasseau, J. J. Jaeger, Y. Chaimanee, A. N. Soe, C. Sein, and H. Bocherens. 2022. \u201cEvolutionary Ecology of Miocene Hominoid Primates in Southeast Asia.\u201d <em>Scientific Reports<\/em> 12 (1): 1\u201312.<\/p>\n<p class=\"import-Normal\">Hammond, Ashley, Lorenzo Rook, Alisha D.Anaya, Elisabetta Cioppi, Lo\u00efc Costeur, Salvadore Moy\u00e0-Sol\u00e0, and Sergio Alm\u00e9cija. 2020. \u201cInsights into the Lower Torso in Late Miocene Hominoid Oreopithecus bambolii.\u201d <em>Proceedings of the National Academy of Sciences<\/em> 117 (1): 278\u2013284.<\/p>\n<p class=\"import-Normal\">Harrison, Terry. 2010. \u201cApes among the Tangled Branches of Human Origins.\u201d <em>Science<\/em> 327 (5965): 532\u2013534.<\/p>\n<p class=\"import-Normal\">Harrison, Terry. 2016. \u201cThe Fossil Record and Evolutionary History of Hylobatids.\u201d In <em>Evolution of Gibbons and Siamang<\/em>, edited by Ullrich H. Reichard, Hirohisa Hirai, and Claudia Barelli, 91\u2013110. New York: Springer.<\/p>\n<p class=\"import-Normal\">Ibrahim, Yasamin Kh., Lim Tze Tshen, Kira E. Westaway, Earl of Cranbrook, Louise Humphrey, Ross Fatihah Muhammad, Jian-xin Zhao, and Lee Chai Peng. 2013. \u201cFirst Discovery of Pleistocene Orangutan (<em>Pongo<\/em> sp.) Fossils in Peninsular Malaysia: Biogeographic and Paleoenvironmental Implications.\u201d <em>Journal of Human Evolution<\/em> 65 (6): 770\u2013797.<\/p>\n<p class=\"import-Normal\">Israfil, Hulya, Sarah M. Zehr, Alan R. Mootnick, Maryellen Ruvolo, and Michael E. Steiper. 2011. \u201cUnresolved Molecular Phylogenies of Gibbons and Siamangs (Family: Hylobatidae) Based on Mitochondrial, Y-linked, and X-linked Loci Indicate a Rapid Miocene Radiation or Sudden Vicariance Event.\u201d <em>Molecular Phylogenetics and Evolution<\/em> 58 (3): 447\u2013455.<\/p>\n<p class=\"import-Normal\">Jablonski, Nina G., and George Chaplin. 2009. \u201cThe Fossil Record of Gibbons.\u201d In <em>The Gibbons<\/em>, edited by Danielle Whittaker and Susan Lappan, 111\u2013130. New York: Springer.<\/p>\n<p class=\"import-Normal\">Jones, F. Wood. 1916. <em>Arboreal Man<\/em>. London: Edward Arnold.<\/p>\n<p class=\"import-Normal\">Kay, Richard F. 1977. \u201cDiets of Early Miocene African Hominoids.\u201d <em>Nature<\/em> 268 (5621): 628\u2013630.<\/p>\n<p class=\"import-Normal\">Kay, Richard F. 2015. \u201cBiogeography in Deep Time: What Do Phylogenetics, Geology, and Paleoclimate Tell Us about Early Platyrrhine Evolution?\u201d <em>Molecular Phylogenetics and Evolution<\/em> 82 (B): 358\u2013374.<\/p>\n<p class=\"import-Normal\">Kay, Richard F., and John G. Fleagle. 2010. \u201cStem Taxa, Homoplasy, Long Lineages, and the Phylogenetic Position of <em>Dolichocebus<\/em>.\u201d <em>Journal of Human Evolution<\/em> 59 (2): 218\u2013222.<\/p>\n<p class=\"import-Normal\">Kay, Richard F., Jonathan M. G. Perry, Michael Malinzak, Kari L. Allen, E. Christopher Kirk, J. Michael Plavcan, and John G. Fleagle. 2012. \u201cPaleobiology of Santacrucian Primates.\u201d In <em>Early Miocene Paleobiology in Patagonia: High-Latitude Paleocommunities of the Santa Cruz Formation<\/em>, edited by Sergio F. Vizca\u00edno, Richard F. Kay, and M. Susana Bargo, 306\u2013330. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Kay, Richard F., Daniel O Schmitt, Christopher J. Vinyard, Jonathan M. G. Perry, Nobuo Shigehara, Masanaru Takai, and Naoko Egi. 2004. \u201cThe Paleobiology of Amphipithecidae, South Asian Late Eocene Primates.\u201d <em>Journal of Human Evolution<\/em> 46 (1): 3\u201325.<\/p>\n<p class=\"import-Normal\">Kay, Richard F., and Elwyn L. Simons. 1980. \u201cThe Ecology of Oligocene African Anthropoidea.\u201d <em>International Journal of Primatology<\/em> 1 (1): 21\u201337.<\/p>\n<p class=\"import-Normal\">Kay, Richard F., Richard W. Thorington, and Peter Houde. 1990. \u201cEocene Plesiadapiform Shows Affinities with Flying Lemurs Not Primates.\u201d <em>Nature<\/em> 345 (6273): 342\u2013344.<\/p>\n<p class=\"import-Normal\">Kelley, Jay. 2002. \u201cThe Hominoid Radiation in Asia.\u201d In <em>The Primate Fossil Record<\/em>, edited by Walter C. Hartwig, 369\u2013384. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Kirk, E. Christopher, and Elwyn L. Simons. 2001. \u201cDiets of Fossil Primates from the Fayum Depression of Egypt: A Quantitative Analysis of Molar Shearing.\u201d <em>Journal of Human Evolution<\/em> 40 (3): 203\u2013229.<\/p>\n<p class=\"import-Normal\">Kirk, E. Christopher, and Blythe A. Williams. 2011. \u201cNew Adapiform Primate of Old World Affinities from the Devil\u2019s Graveyard Formation of Texas.\u201d <em>Journal of Human Evolution<\/em> 61 (2): 156\u2013168.<\/p>\n<p class=\"import-Normal\">Krause, David W. 1991. \u201cWere Paromomyids Gliders? Maybe, Maybe Not.\u201d <em>Journal of Human Evolution<\/em> 21 (3): 177\u2013188.<\/p>\n<p class=\"import-Normal\">Kunimatsu, Yutaka, Masato Nakatsukasa, Yoshihiro Sawada, Tetsuya Sakai, Masayuki Hyodo, Hironobu Hyodo, Tetsumaru Itaya, et al. 2007. \u201cA New Late Miocene Great Ape from Kenya and Its Implications for the Origins of African Great Apes and Humans.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 104 (49): 19220\u201319225.<\/p>\n<p class=\"import-Normal\">Maclatchy, Laura. 2004. \u201cThe Oldest Ape.\u201d <em>Evolutionary Anthropology: Issues, News, and Reviews<\/em> 13 (3): 90\u2013103.<\/p>\n<p class=\"import-Normal\">Marivaux, Laurent, Yaowalak Chaimanee, St\u00e9phane Ducrocq, Bernard Marandat, Jean Sudre, Aung Naing Soe, Soe Thura Tun, Wanna Htoon, and Jean-Jacques Jaeger. 2003. \u201cThe Anthropoid Status of a Primate from the Late Middle Eocene Pondaung Formation (Central Myanmar): Tarsal Evidence.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 100 (23): 13173\u201313178.<\/p>\n<p class=\"import-Normal\">Marivaux, Laurent, Anusha Ramdarshan, El Mabrouk Essid, Wissem Marzougui, Hayet Khayati Ammar, Renaud Lebrun, Bernard Marandat, Gilles Merzeraud, Rodolphe Tabuce, and Monique Vianey-Liaud. 2013. \u201c<em>Djebelemur<\/em>, a Tiny Pre-ToothCombed Primate from the Eocene of Tunisia: A Glimpse into the Origin of Crown Strepsirrhines.\u201d <em>PLoS ONE<\/em> 8 (12): e80778. <a class=\"rId116\" href=\"https:\/\/doi.org\/10.1371\/journal.pone.0080778\">doi.org\/10.1371\/journal.pone.0080778<\/a>.<\/p>\n<p class=\"import-Normal\">Martin, R. D. 1968. \u201cTowards a New Definition of Primates.\u201d <em>Man<\/em> (N.S.) 3 (3): 377\u2013401.<\/p>\n<p class=\"import-Normal\">Martin, R. D. 1972. \u201cAdaptive Radiation and Behaviour of the Malagasy Primates.\u201d <em>Philosophical Transactions of the Royal Society B: Biological Sciences<\/em> 264 (862): 295\u2013352.<\/p>\n<p class=\"import-Normal\">Martin, R. D. 1990. <em>Primate Origins and Evolution, a Phylogenetic Reconstruction<\/em>. Princeton: Princeton University Press.<\/p>\n<p class=\"import-Normal\">McBrearty, Sally, and Nina G. Jablonski. 2005. \u201cFirst Fossil Chimpanzee.\u201d <em>Nature<\/em> 437 (7055): 105\u2013108.<\/p>\n<p class=\"import-Normal\">Michel, Lauren A., Daniel J. Peppe, James A. Lutz, Stephen G. Driese, Holly M. Dunsworth, William E. H. Harcourt-Smith, William H. Horner, Thomas Lehmann, Sheila Nightingale, and Kieran P. McNulty. 2014. \u201cRemnants of an Ancient Forest Provide Ecological Context for Early Miocene Fossil Apes.\u201d <em>Nature Communications<\/em> 5: 1-9.<\/p>\n<p class=\"import-Normal\">Miller, E. R., B. R. Benefit, M. L. McCrossin, J. M. Plavcan, M. G. Leakey, A. N. El-Barkooky, M. A. Hamdan, M. K. A. Gawad, S. M. Hassan, and E. L. Simons. 2009. \u201cSystematics of Early and Middle Miocene Old World Monkeys.\u201d <em>Journal of Human Evolution<\/em> 57 (3): 195\u2013211.<\/p>\n<p class=\"import-Normal\">Mocke, H., M. Pickford, B. Senut, and D. Gommery. 2022. \u201cNew Information about African Late Middle Miocene to Latest Miocene (13\u20135.5 Ma) Hominoidea. <em>Communications of the Geological Survey of Namibia<\/em> 24: 33\u201366.<\/p>\n<p class=\"import-Normal\">Moy\u00e0-Sol\u00e0, Salvadore, David M. Alba, Sergio Alm\u00e9cija, Isaac Casanovas-Vilar, Meike K\u00f6hler, Soledad De Esteban-Trivigno, Josep M. Robles, Jordi Galindo, and Josep Fortuny. 2009. \u201cA Unique Middle Miocene European Hominoid and the Origins of the Great Ape and Human Clade.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 106 (24): 9601\u20139606.<\/p>\n<p class=\"import-Normal\">Moy\u00e0-Sol\u00e0, Salvador, Meike K\u00f6hler, David M. Alba, Isaac Casanovas-Vilar, and Jordi Galindo. 2004. \u201c<em>Pierolapithecus catalaunicus<\/em>, a New Middle Miocene Great Ape from Spain.\u201d <em>Science<\/em> 306 (5700): 1339\u20131344.<\/p>\n<p class=\"import-Normal\">Ni, Xijun, Daniel L. Gebo, Marian Dagosto, Jin Meng, Paul Tafforeau, John J. Flynn, and K. Christopher Beard. 2013. \u201cThe Oldest Known Primate Skeleton and Early Haplorhine Evolution.\u201d <em>Nature<\/em> 498 (7452): 60\u201364.<\/p>\n<p class=\"import-Normal\">Perry, Jonathan M. G., Richard F. Kay, Sergio F. Vizca\u00edno, and M. Susana Bargo. 2010. \u201cTooth Root Size, Chewing Muscle Leverage, and the Biology of <em>Homunculus patagonicus<\/em> (Primates) from the Late Early Miocene of Patagonia.\u201d <em>Ameghiniana<\/em> 47 (3): 355\u2013371.<\/p>\n<p class=\"import-Normal\">Perry, Jonathan M. G., Richard F. Kay, Sergio F. Vizca\u00edno, and M. Susana Bargo. 2014. \u201cOldest Known Cranium of a Juvenile New World Monkey (Early Miocene, Patagonia, Argentina): Implications for the Taxonomy and the Molar Eruption Pattern of Early Platyrrhines.\u201d <em>Journal of Human Evolution<\/em> 74: 67\u201381.<\/p>\n<p class=\"import-Normal\">Pickford, Martin, Yves Coppens, Brigitte Senut, Jorge Morales, and Jos\u00e9 Braga. 2009. \u201cLate Miocene Hominoid from Niger.\u201d <em>Comptes Rendus Palevol<\/em> 8 (4): 413\u2013425.<\/p>\n<p class=\"import-Normal\">Pilbeam, David. 1982. \u201cNew Hominoid Skull Material from the Miocene of Pakistan.\u201d <em>Nature<\/em> 295 (5846): 232\u2013234.<\/p>\n<p class=\"import-Normal\">Pilbeam, David, Michael D. Rose, John C. Barry, and S. M. Ibrahim Shah. 1990. \u201cNew <em>Sivapithecus<\/em> Humeri from Pakistan and the Relationship of <em>Sivapithecus<\/em> and <em>Pongo<\/em>.\u201d <em>Nature<\/em> 348 (6298): 237\u2013239.<\/p>\n<p class=\"import-Normal\">Rasmussen, D. Tab. 1990. \u201cPrimate Origins: Lessons from a Neotropical Marsupial.\u201d <em>American Journal of Primatology<\/em> 22 (4): 263\u2013277.<\/p>\n<p class=\"import-Normal\">Ravosa, Matthew J. 1996. \u201cMandibular Form and Function in North American and European Adapidae and Omomyidae.\u201d <em>Journal of Morphology<\/em> 229 (2): 171\u2013190.<\/p>\n<p class=\"import-Normal\">R\u00f6gl, Fred. 1999. \u201cMediterranean and Paratethys Palaeogeography during the Oligocene and Miocene.\u201d In <em>Hominoid Evolution and Climatic Change in Europe<\/em>, edited by Jorge Agust\u00ed, Lorenzo Rook, and Peter Andrews, 8\u201322. Cambridge: Cambridge University Press.<\/p>\n<p class=\"import-Normal\">Rosas, A., A. Garc\u00eda-Tabernero, D. Fidalgo, M. Fero Me\u00f1e, C. Ebana Ebana, F. Esono Mba, and P. Saladie. 2022. \u201cThe Scarcity of Fossils in the African Rainforest: Archaeo-Paleontological Surveys and Actualistic Taphonomy in Equatorial Guinea.\u201d <em>Historical Biology<\/em> 34 (8): 1\u20139.<\/p>\n<p class=\"import-Normal\">Rose, Kenneth D., and Thomas M. Bown. 1984. \u201cGradual Phyletic Evolution at the Generic Level in Early Eocene Omomyoid Primates.\u201d <em>Nature<\/em> 309 (5965): 250\u2013252.<\/p>\n<p class=\"import-Normal\">Rose, Kenneth D., Rachel H. Dunn, Kishor Kumar, Jonathan M. G. Perry, Kristen A. Prufrock, Rajendra S. Rana, and Thierry Smith. 2018. \u201cNew Fossils from Tadkeshwar Mine (Gujarat, India) Increase Primate Diversity from the Early Eocene Cambay Shale.\u201d <em>Journal of Human Evolution<\/em> 122: 93\u2013107.<\/p>\n<p class=\"import-Normal\">Rose, Kenneth D., and John M. Rensberger. 1983. \u201cUpper Dentition of <em>Ekgmowechashala<\/em> (Omomyoid Primate) from the John Day Formation, Oligo-Miocene of Oregon.\u201d <em>Folia Primatologica<\/em> 41(1-2): 102\u2013111.<\/p>\n<p class=\"import-Normal\">Rosenberger, Alfred L. 2010. \u201cPlatyrrhines, PAUP, Parallelism, and the Long Lineage Hypothesis: A Reply to Kay <em>et al. <\/em>(2008).\u201d <em>Journal of Human Evolution<\/em> 59 (2): 214\u2013217.<\/p>\n<p class=\"import-Normal\">Ross, Callum F. 2000. \u201cInto the Light: The Origins of Anthropoidea.\u201d <em>Annual Review of Anthropology<\/em> 29: 147\u2013194.<\/p>\n<p class=\"import-Normal\">Ross, Callum F., and Richard F. Kay, eds. 2004. <em>Anthropoid Origins: New Visions<\/em>. New York: Kluwer Academic\/Plenum Publishers.<\/p>\n<p class=\"import-Normal\">Russo, Gabrielle A. 2016. \u201cComparative Sacral Morphology and the Reconstructed Tail Lengths of Five Extinct Primates: <em>Proconsul heseloni<\/em>, <em>Epipliopithecus vindobonensis<\/em>, <em>Archaeolemur edwardsi<\/em>, <em>Megaladapis grandidieri<\/em>, and <em>Palaeopropithecus kelyus<\/em>.\u201d <em>Journal of Human Evolution<\/em> 90: 135\u2013162.<\/p>\n<p class=\"import-Normal\">Schmid, Peter. 1979. \u201cEvidence of Microchoerine Evolution from Dielsdorf (Z\u00fcrich Region, Switzerland): A Preliminary Report.\u201d <em>Folia Primatologica<\/em> 31 (4): 301\u2013311.<\/p>\n<p class=\"import-Normal\">Seiffert, Erik R. 2012. \u201cEarly Primate Evolution in Afro-Arabia.\u201d <em>Evolutionary Anthropology: Issues, News, and Reviews<\/em> 21 (6): 239\u2013253.<\/p>\n<p class=\"import-Normal\">Seiffert, Erik R., Jonathan M. G. Perry, Elwyn L. Simons, and Doug M. Boyer. 2009. \u201cConvergent Evolution of Anthropoid-like Adaptations in Eocene Adapiform Primates.\u201d <em>Nature<\/em> 461 (7267): 1118\u20131121.<\/p>\n<p class=\"import-Normal\">Seiffert, Erik R., Elwyn L. Simons, and Yousry Attia. 2003. \u201cFossil Evidence for an Ancient Divergence of Lorises and Galagos.\u201d <em>Nature<\/em> 422 (6930): 421\u2013424.<\/p>\n<p class=\"import-Normal\">Seiffert, Erik R., Elwyn L. Simons, Doug M. Boyer, Jonathan M. G. Perry, Timothy M. Ryan, and Hesham M. Sallam. 2010. \u201cA Fossil Primate of Uncertain Affinities from the Earliest Late Eocene of Egypt.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 107 (21): 9712\u20139717.<\/p>\n<p class=\"import-Normal\">Seiffert, Erik R., Elwyn L. Simons, and Cornelia V. M. Simons. 2004. \u201cPhylogenetic, Biogeographic, and Adaptive Implications of New Fossil Evidence Bearing on Crown Anthropoid Origins and Early Stem Catarrhine Evolution.\u201d In <em>Anthropoid Origins: New Visions<\/em>, edited by Callum F. Ross and Richard F. Kay, 157\u2013182. New York: Kluwer\/Plenum Publishing.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L. 1961. \u201cThe Phyletic Position of <em>Ramapithecus<\/em>.\u201d <em>Postilla<\/em> 57: 1\u20139.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L. 2001. \u201cThe Cranium of <em>Parapithecus grangeri<\/em>, an Egyptian Oligocene Anthropoidean Primate.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 98 (4): 7892\u20137897.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L. 2004. \u201cThe Cranium and Adaptations of <em>Parapithecus grangeri<\/em>, a Stem Anthropoid From the Fayum Oligocene of Egypt.\u201d In <em>Anthropoid Origins: New Visions<\/em>, edited by Callum F. Ross and Richard F. Kay, 183\u2013204. New York: Kluwer\/Plenum Publishing.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L. 2008. \u201cEocene and Oligocene Mammals of the Fayum, Egypt.\u201d In <em>Elwyn Simons: A Search for Origins<\/em>, edited by John G. Fleagle and Christopher C. Gilbert, 87\u2013105. New York: Springer.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L., and D. Tab Rasmussen. 1994a. \u201cA Remarkable Cranium of <em>Plesiopithecus teras<\/em> (Primates, Prosimii) from the Eocene of Egypt.\u201d <em>Proceedings of the National Academy of Sciences<\/em> <em>of the United States of America<\/em> 91(21): 9946\u20139950.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L., and D. Tab Rasmussen. 1994b. \u201cA Whole New World of Ancestors: Eocene Anthropoideans from Africa.\u201d <em>Evolutionary Anthropology<\/em> 3 (4): 128\u2013139.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L., and D. Tab Rasmussen. 1996. \u201cSkull of <em>Catopithecus browni<\/em>, an Early Tertiary Catarrhine.\u201d <em>American Journal of Physical Anthropology<\/em> 100 (2): 261\u2013292.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L., and Erik R. Seiffert. 1999. \u201cA Partial Skeleton of <em>Proteopithecus<\/em> <em>sylviae<\/em> (Primates Anthropoidea): First Associated Dental and Postcranial Remains of an Eocene Anthropoidean.\u201d <em>Comptes Rendus de l'Acad\u00e9mie des Sciences, Paris<\/em> 329 (12): 921\u2013927.<\/p>\n<p class=\"import-Normal\">Simons, Elwyn L., Erik R. Seiffert, Timothy M. Ryan, and Yousry Attia. 2007. \u201cA Remarkable Female Cranium of the Early Oligocene Anthropoid <em>Aegyptopithecus zeuxis<\/em> (Catarrhini, Propliopithecidae).\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 104 (21): 8731\u20138736.<\/p>\n<p class=\"import-Normal\">Simpson, George Gaylord. 1933. \u201cThe \u2018Plagiaulacoid\u2019 Type of Mammalian Dentition: A Study of Convergence.\u201d <em>Journal of Mammalogy<\/em> 14 (2): 97\u2013107.<\/p>\n<p class=\"import-Normal\">Simpson, George Gaylord. 1940. \u201cReview of the Mammal-Bearing Tertiary of South America.\u201d <em>Proceedings of the American Philosophical Society<\/em> 83 (5): 649\u2013709.<\/p>\n<p class=\"import-Normal\">Simpson, George Gaylord. 1967. \u201cThe Tertiary Lorisiform Primates of Africa.\u201d <em>Bulletin of the Museum of Comparative Zoology at Harvard University<\/em> 136: 39\u201362.<\/p>\n<p class=\"import-Normal\">Smith, G. Elliot. 1912. \u201cThe Evolution of Man.\u201d <em>Smithsonian Institute Annual Report <\/em>2012: 553\u2013572.<\/p>\n<p class=\"import-Normal\">Smith, Thierry, Kenneth D. Rose, and Philip D. Gingerich. 2006. \u201cRapid Asia\u2013Europe\u2013North America Geographic Dispersal of Earliest Eocene Primate <em>Teilhardina<\/em> during the Paleocene\u2013Eocene Thermal Maximum.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 103 (30): 11223\u201311227.<\/p>\n<p class=\"import-Normal\">Stehlin, Hans G. 1912. \u201cDie s\u00e4ugetiere des schweizerischen Eocaens. Siebenter teil, erst h\u00e4lfte: <em>Adapis<\/em>\u201d [\u201cThe Mammals of the Swiss Eocene. Part Seven, First Half: Adapis\u201d]. <em>Abhandlungen der Schweizerischen Pal\u00e4ontologischen Gesellschaft<\/em> 38: 1165\u20131298.<\/p>\n<p class=\"import-Normal\">Strait, Suzanne G. 2001. \u201cDietary Reconstruction of Small-Bodied Omomyoid Primates.\u201d <em>Journal of Vertebrate Paleontology<\/em> 21 (2): 322\u2013334.<\/p>\n<p class=\"import-Normal\">Sussman, Robert W. 1991. \u201cPrimate Origins and the Evolution of Angiosperms.\u201d <em>American Journal of Primatology<\/em> 23 (4): 209\u2013223.<\/p>\n<p class=\"import-Normal\">Suwa, Gen, Reiko T. Kono, Shigehiro Katoh, Berhane Asfaw, and Yonas Beyene. 2007. \u201cA New Species of Great Ape from the Late Miocene Epoch in Ethiopia.\u201d <em>Nature<\/em> 448 (7156): 921\u2013924.<\/p>\n<p class=\"import-Normal\">Teaford, Mark F., Mary C. Maas, and Elwyn L. Simons. 1996. \u201cDental Microwear and Microstructure in Early Oligocene Primates from the Fayum, Egypt: Implications for Diet.\u201d <em>American Journal of Physical Anthropology<\/em> 101 (4): 527\u2013543.<\/p>\n<p class=\"import-Normal\">Ungar, Peter S., and Richard F. Kay. 1995. \u201cThe Dietary Adaptations of European Miocene Catarrhines.\u201d <em>Proceedings of the National Academy of Sciences of the United States of America<\/em> 92 (12): 5479\u20135481.<\/p>\n<p class=\"import-Normal\">Wang, Cui-Bin, Ling-Xia Zhao, Chang-Zhu Jin, Yuan Wang, Da-Gong Qin, and Wen-Shi Pan. 2014. \u201cNew Discovery of Early Pleistocene Orangutan Fossils from Sanhe Cave in Chongzuo, Guangxi, Southern China.\u201d <em>Quaternary International<\/em> 354: 68\u201374.<\/p>\n<p class=\"import-Normal\">Ward, C. V., A. Walker, and M. F. Teaford. 1991. \u201c<em>Proconsul<\/em> Did Not Have a Tail.\u201d <em>Journal of Human Evolution<\/em> 21 (3): 215\u2013220.<\/p>\n<p class=\"import-Normal\">Wheeler, Brandon C. 2010. \u201cCommunity Ecology of the Middle Miocene Primates of La Venta, Colombia: The Relationship between Ecological Diversity, Divergence Time, and Phylogenetic Richness.\u201d <em>Primates<\/em> 51 (2): 131\u2013138.<\/p>\n<p class=\"import-Normal\">Williams, Blythe A., and Richard F. Kay. 1995. \u201cThe Taxon Anthropoidea and the Crown Clade Concept.\u201d <em>Evolutionary Anthropology<\/em> 3 (6): 188\u2013190.<\/p>\n<p class=\"import-Normal\">Williams, Blythe A., Richard F. Kay, and E. Christopher Kirk. 2010a. \u201cNew Perspectives on Anthropoid Origins.\u201d <em>Proceedings of the National Academy<\/em> <em>of the United States of America<\/em> 107 (11): 4797\u20134804.<\/p>\n<p class=\"import-Normal\">Williams, Blythe A., Richard F. Kay, E. Christopher Kirk, and Callum F. Ross. 2010b. \u201c<em>Darwinius masillae<\/em> Is a European Middle Eocene Stem Strepsirrhine\u2014A Reply to Franzen et al.\u201d <em>Journal of Human Evolution<\/em> 59(5): 567\u2013573.<\/p>\n<p class=\"import-Normal\">Wilson Mantilla, G. P., S. G. B. Chester, W. A. Clemens, J. R. Moore, C. J. Sprain, B. T. Hovatter, W. S. Mitchell, W. W. Mans, R. Mundil, and P. R. Renne. 2021. \u201cEarliest Palaeocene Purgatoriids and the Initial Radiation of Stem Primates.\u201d <em>Royal Society Open Science<\/em> 8(2):210050. doi:10.1098\/rsos.210050.<\/p>\n<h2 class=\"import-Normal\">Acknowledgments<\/h2>\n<p class=\"import-Normal\">We are immensely grateful to the editors of this book, Drs. Beth Shook, Lara Braff, Katie Nelson, and Kelsie Aguilera, for their time and commitment to making this knowledge freely accessible to all, and for giving us the opportunity to participate in this important project.<\/p>\n<\/div>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2090\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2090\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2091\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2091\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2082\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2082\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2083\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2083\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2087\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2087\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2084\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2084\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2085\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2085\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_1985\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_1985\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2093\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2093\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2094\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2094\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2095\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2095\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2097\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2097\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2098\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2098\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2099\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2099\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2100\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2100\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2101\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2101\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2730\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2730\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2109\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2109\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2105\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2105\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_1875\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_1875\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2106\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2106\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2040\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2040\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_1997\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_1997\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2000\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2000\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2113\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2113\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2116\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2116\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2129\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2129\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2731\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2731\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_1474\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_1474\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2118\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2118\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2119\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2119\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2122\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2122\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2123\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2123\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_410_2125\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_410_2125\"><div tabindex=\"-1\"><\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><\/div>","protected":false},"author":94,"menu_order":14,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":[],"pb_section_license":""},"chapter-type":[],"contributor":[],"license":[],"class_list":["post-410","chapter","type-chapter","status-publish","hentry"],"part":20,"_links":{"self":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/chapters\/410","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/wp\/v2\/users\/94"}],"version-history":[{"count":9,"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/chapters\/410\/revisions"}],"predecessor-version":[{"id":808,"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/chapters\/410\/revisions\/808"}],"part":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/parts\/20"}],"metadata":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/chapters\/410\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/wp\/v2\/media?parent=410"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/pressbooks\/v2\/chapter-type?post=410"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/wp\/v2\/contributor?post=410"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorationsversiontwo\/wp-json\/wp\/v2\/license?post=410"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}