{"id":254,"date":"2023-03-23T01:42:07","date_gmt":"2023-03-23T05:42:07","guid":{"rendered":"https:\/\/opentextbooks.concordia.ca\/explorations\/chapter\/7\/"},"modified":"2025-07-17T13:16:34","modified_gmt":"2025-07-17T17:16:34","slug":"7","status":"publish","type":"chapter","link":"https:\/\/opentextbooks.concordia.ca\/explorations\/chapter\/7\/","title":{"raw":"Stones and Bones: Studying the Fossil Record","rendered":"Stones and Bones: Studying the Fossil Record"},"content":{"raw":"<div class=\"__UNKNOWN__\">\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Sarah S. King, Ph.D., Cerro Coso Community College<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Kara Jones, M.A., Ph.D. student, University of Nevada Las Vegas<\/p>\r\n<p class=\"import-Normal\"><em>This chapter<\/em><em> is a revision from \"<\/em><a class=\"rId6\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\"><em>Chapter 7: Understanding the Fossil Context<\/em><\/a><em>\u201d by Sarah King and Lee Anne Zajicek. <\/em><em>In <\/em><a class=\"rId7\" 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=\"rId8\" 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: #ffffff;\">Learning Objectives<\/span><\/h2>\r\n<\/header>\r\n<div class=\"textbox__content\">\r\n<ul>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Identify the different types of fossils and describe how they are formed.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Discuss relative and chronometric dating methods, the type of material they analyze, and their applications.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Describe the methods used to reconstruct past environments.<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Interpret a site using the methods described in this chapter.<\/li>\r\n<\/ul>\r\n<\/div>\r\n<\/div>\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossil Study: An Evolving Process<\/h2>\r\n<h3 class=\"import-Normal\"><strong>Mary Anning and the Age of Wonder<\/strong><\/h3>\r\n[caption id=\"\" align=\"alignleft\" width=\"206\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/05\/image12.jpg\" alt=\"Woman points to dog and fossil on the ground.\" width=\"206\" height=\"248\" \/> Figure 7.1: An oil painting of Mary Anning and her dog, Tray, prior to 1845. The \u201cJurassic Coast\u201d of Lyme Regis is in the background. Notice that Anning is pointing at a fossil. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Mary_Anning_by_B._J._Donne.jpg\">Mary Anning by B. J. Donne<\/a> from the Geological Society\/NHMPL is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n\r\nMary Anning (1799\u20131847) is likely the most famous fossil hunter you\u2019ve never heard of (Figure 7.1). Anning lived her entire life in Lyme Regis on the Dorset coast in England. As a woman, born to a poor family, with minimal education (even by 19th-century standards), the odds were against Anning becoming a scientist (Emling 2009, xii). It was remarkable that Anning was eventually able to influence the great scientists of the day with her fossil discoveries and her subsequent hypotheses regarding evolution.\r\n<p class=\"import-Normal\">The time when Anning lived was a remarkable period in human history because of the Industrial Revolution in Britain. Moreover, the scientific discoveries of the 18th and 19th centuries set the stage for great leaps of knowledge and understanding about humans and the natural world. Barely a century earlier, Sir Isaac Newton had developed his theories on physics and become the president of the Royal Society of London (Dolnick 2011, 5). In this framework, the pursuit of intellectual and scientific discovery became a popular avocation for many individuals, the vast majority of whom were wealthy men (Figure 7.2).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"358\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image22-1.png\" alt=\"Robed figure near a rock structure.\" width=\"358\" height=\"273\" \/> Figure 7.2: A Walk at Dusk, 1830\u20131835, by Caspar David Friedrich, is a painting likely of a dolmen, a megalithic (large rock) tomb. Dolmens were built throughout Europe, five to six thousand years ago. Scholars were fascinated by the ancient world, which was an accepted part of Earth\u2019s history, even if explanation defied nonsecular thought. Credit: <a href=\"https:\/\/www.getty.edu\/art\/collection\/object\/103RJX\">A Walk at Dusk object 93.PA.14<\/a> by Casper David Friedrich German, 1774\u20131840, Paul Getty Museum, is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a> and part of the <a href=\"https:\/\/www.getty.edu\/projects\/open-content-program\/\">Getty Open Content Program<\/a>.[\/caption]\r\n<p class=\"import-Normal\">In spite of the expectations of Georgian English society to the contrary, Anning became a highly successful fossil hunter as well as a self-educated geologist and anatomist. The geology of Lyme Regis, with its limestone cliffs, provided a fortuitous backdrop for Anning\u2019s lifework. Now called the \u201cJurassic Coast,\u201d Lyme Regis has always been a rich source for fossilized remains (Figure 7.3). Continuing her father\u2019s passion for fossil hunting, Anning scoured the crumbling cliffs after storms for fossilized remains and shells. The work was physically demanding and downright dangerous. In 1833, while searching for fossils, Anning lost her beloved dog in a landslide and nearly lost her own life in the process (Emling 2009).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"283\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image14-1.jpg\" alt=\"Rocky coastline and cliffs.\" width=\"283\" height=\"212\" \/> Figure 7.3: The \u201cJurassic Coast\u201d of Lyme Regis: the home of fossil hunter Mary Anning. Credit: <a href=\"https:\/\/pixabay.com\/photos\/lyme-regis-coast-sea-cliffs-924431\/\">Lyme-regis-coast-sea-cliffs-924431<\/a> by <a href=\"https:\/\/pixabay.com\/users\/jstarj-884623\/\">jstarj<\/a> has been designated to the <a href=\"https:\/\/creativecommons.org\/share-your-work\/public-domain\/cc0\/\">public domain (CC0)<\/a> under a <a href=\"https:\/\/pixabay.com\/service\/terms\/#license\">Pixabay License<\/a>.[\/caption]\r\n<p class=\"import-Normal\">Around the age of ten, Anning located and excavated a complete fossilized skeleton of an ichthyosaurus (\u201cfish lizard\u201d). She eventually found <em>Pterodactylus macronyx<\/em> and a 2.7-meter <em>Plesiosaurus<\/em>, considered by many to be her greatest discovery (Figure 7.4). These discoveries proved that there had been significant changes in the way living things appeared throughout the history of the world. Like many of her peers, including Darwin, Anning had strong religious convictions. However, the evidence that was being found in the fossil record was contradictory to the Genesis story in the Bible. In <em>The Fossil Hunter: Dinosaurs, Evolution, and the Woman Whose Discoveries Changed the World<\/em>, Anning\u2019s biographer Shelley Emling (2009, 38) notes, \u201cthe puzzling attributes of Mary\u2019s fossil [ichthyosaurus] struck a blow at this belief and eventually helped pave the way for a real understanding of life before the age of humans.\u201d<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"247\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image21.png\" alt=\"Plesiosaurus drawing.\" width=\"247\" height=\"375\" \/> Figure 7.4: Plesiosaurus, illustrated and described by Mary Anning in an undated handwritten letter. Credit: <a href=\"https:\/\/wellcomecollection.org\/works\/cezbevj4\">Autograph letter concerning the discovery of plesiosaurus<\/a> by Mary Anning (1799\u20131847) from the <a href=\"https:\/\/wellcomecollection.org\">Wellcome Collection<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY 4.0 License<\/a>.[\/caption]\r\n\r\nIntellectual and scientific debate now had physical evidence to support the theory of evolution, which would eventually result in Darwin\u2019s seminal work,<em> On the Origin of Species<\/em> (1859). Anning\u2019s discoveries and theories were appreciated and advocated by her friends, intellectual men who were associated with the Geological Society of London. Regrettably, this organization was closed to women, and Anning received little official recognition for her contributions to the fields of natural history and paleontology. It is clear that Anning\u2019s knowledge, diligence, and uncanny luck in finding magnificent specimens of fossils earned her unshakeable credibility and made her a peer to many antiquarians (Emling 2009).\r\n<p class=\"import-Normal\">Fossil hunting is still providing evidence and a narrative of the story of Earth. Mary Anning recognized the value of fossils in understanding natural history and relentlessly championed her theories to the brightest minds of her day. Anning\u2019s ability to creatively think \u201coutside the box\u201d\u2014skillfully assimilating knowledge from multiple academic fields\u2014was her gift to our present understanding of the fossil record. Given how profoundly Anning has shaped how we, in the modern day, think about the origins of life, it is surprising that her contributions have been so marginalized. Anning\u2019s name should be on the tip of everyone\u2019s tongue. Fortunately, at least in one sense of the word, it is. The well-known tongue twister, below, may have been written about Mary Anning:<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">She sells sea-shells on the sea-shore.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">The shells she sells are sea-shells, I\u2019m sure.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">For if she sells sea-shells on the sea-shore<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">Then I\u2019m sure she sells sea-shore shells.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">\u2014T. Sullivan (1908)<\/p>\r\n\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Developing Modern <\/strong><strong>Methods<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As Mary Anning\u2019s story suggests, scientists in Europe were working at a time dominated by western Christian tradition. Literal interpretations of the bible did not allow for the long, slow processes of geological or evolutionary change to operate. However, many scientists were making observations that did not fit the biblical narrative. During the 18th century, Scotsman James Hutton\u2019s work on the formation of Earth provided a much longer timeline of events than previous biblical interpretations would allow. Hutton\u2019s theory of <strong>[pb_glossary id=\"826\"]Deep Time[\/pb_glossary]<\/strong> was crucial to the understanding of fossils. Deep Time gave the history of Earth enough time\u20144.543 billion years\u2014to encompass <strong>[pb_glossary id=\"828\"]continental drift[\/pb_glossary]<\/strong>, the evolution of species, and the fossilization process. A second Scotsman, Charles Lyell, propelled Hutton\u2019s work into his own theory of <strong>[pb_glossary id=\"830\"]uniformitarianism[\/pb_glossary]<\/strong>, the doctrine that Earth\u2019s geologic formations are the work of slow geologic forces. Lyell\u2019s three-volume work, <em>Principles of Geology<\/em> (1830\u20131833), was influential to naturalist Charles Darwin (see Chapter 2 for more information on Darwin\u2019s work). In fact, Lyell\u2019s first volume accompanied Darwin on his five-year voyage around the world on the <em>HMS Beagle<\/em> (1831\u20131836). The concepts proposed by Lyell gave Darwin an opportunity to apply his working theories of evolution by natural selection and a greater length of time with which to work. These resulting theories were important scientific discoveries and paved the way for the \u201cAge of Wonder\u201d (Holmes 2010, xvi).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"264\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image30-1.jpg\" alt=\"Fossilized shell.\" width=\"264\" height=\"176\" \/> Figure 7.5: Murexsul (Miocene): This fossil was found at the Naval Weapons Center, China Lake, California, in 1945. The fossil was buried deep in the strata and was pulled out of the ground along with a crashed \u201cFat Boy\u201d missile after atomic missile testing (S. Brubaker, personal communication, March 9, 2018). Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Murexsul (Figure 7.6)<\/a> from the <a href=\"https:\/\/maturango.org\/\">Maturango Museum<\/a>, Ridgecrest, California, by Sarah S. King and Lee Anne Zajicek is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\nThe work of Anning, Darwin, Lyell, and many others laid the foundation for the modern methods we use today. Though anthropology is focused on humans and our primate relatives (and not on dinosaurs, as many people wrongly assume), you will see that methods developed in paleontology, geology, chemistry, biology, and physics are often applied in anthropological research. In this chapter, you will learn about the primary methods and techniques employed by biological anthropologists to answer questions about <strong>[pb_glossary id=\"832\"]fossils[\/pb_glossary]<\/strong>, the mineralized copies of once-living organisms (Figure 7.5). Ultimately, these answers provide insights into human evolution. Pay close attention to ways in which modern biological anthropologists use other disciplines to analyze evidence and reconstruct past activities and environments.\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Earth: It's Older than Dirt<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Scientists have developed precise and accurate dating methods based on work in the fields of physics and chemistry. Using these methods, scientists are able to establish the age of Earth as well as approximate ages of the organisms that have lived here. Earth is roughly 4.6 billion years old, give or take a few hundred million years. The first evidence for a living organism appeared around 3.5 billion years ago (<strong>[pb_glossary id=\"844\"]bya[\/pb_glossary]<\/strong>)<strong>.<\/strong> The scale of geologic time can seem downright overwhelming. In order to organize and make sense of Earth\u2019s past, geologists break up that time into subunits, which are human-made divisions along Earth\u2019s timeline. The largest subunit is the <strong>eon. <\/strong>An eon is further divided into <strong>[pb_glossary id=\"836\"]eras[\/pb_glossary],<\/strong> and eras are divided into <strong>[pb_glossary id=\"838\"]periods[\/pb_glossary]<\/strong>. Finally, periods are divided into <strong>[pb_glossary id=\"846\"]epochs[\/pb_glossary]<\/strong> (see Figure 7.6; Williams 2004, 37). Currently, we are living in the Phanerozoic eon, Cenozoic era, Quaternary period, and probably the Holocene epoch\u2014though there is academic debate about the current epoch (see below).<\/p>\r\n\r\n\r\n[caption id=\"attachment_248\" align=\"aligncenter\" width=\"1134\"]<img class=\"wp-image-227 size-full\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17.jpeg\" alt=\"Table of geological time scale and examples. Full text link in caption.\" width=\"1134\" height=\"1300\" \/> Figure 7.6: The Geologic time scale is shown here, with periods broken into eons, eras, periods, and in some cases epochs. Some life forms and geological events are noted for each period. <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\">A full text description of this image is available<\/a>. Credit: <a href=\"https:\/\/www.nps.gov\/subjects\/geology\/time-scale.htm\" target=\"_blank\" rel=\"noopener\">Geologic Time Scale<\/a>, by <a href=\"https:\/\/www.nps.gov\/index.htm\" target=\"_blank\" rel=\"noopener\">National Park Service<\/a>, designed by Trista Thornberry-Ehrlich and Rebecca Port, adapted from ones from <a href=\"https:\/\/www.usgs.gov\/\" target=\"_blank\" rel=\"noopener\">USGS<\/a> and the International Commission on Stratigraphy, is in the <a href=\"https:\/\/www.nps.gov\/aboutus\/disclaimer.htm#:~:text=%C2%A7%C2%A7%20101%2C%20105)\" target=\"_blank\" rel=\"noopener\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">These divisions are based on major changes and events recorded in the geologic record. Events like significant shifts in climate or mass extinctions can be used to mark the end of one geologic time unit and the beginning of another. However, it is important to remember that these borders are not real in a physical sense; they are helpful organizational guidelines for scientific research. There can be debate regarding how the boundaries are defined. Additionally, the methods we use to establish these dates are refined over time, occasionally leading to shifts in established chronology (see the discussion on calibration in the radiocarbon dating section below). For instance, the current epoch has been traditionally known as the <strong>[pb_glossary id=\"840\"]Holocene[\/pb_glossary]<\/strong>. It began almost twelve thousand years ago (<strong>[pb_glossary id=\"842\"]kya[\/pb_glossary]<\/strong>) during the warming period after that last major ice age. Today, there is evidence to indicate human-driven climate change is warming the world and changing the environmental patterns faster than the natural cyclical processes. This has led some scientists within the stratigraphic community to argue for a new epoch beginning around 1950 with the Nuclear Age called the <strong>[pb_glossary id=\"848\"]Anthropocene[\/pb_glossary] <\/strong>(Monastersky 2015; Waters et al. 2016). Nobel Laureate Paul Crutzen places the beginning of the Anthropocene much earlier\u2014at the dawn of the Industrial Revolution, with its polluting effects of burning coal (Crutzen and Stoermer 2000, 17\u201318). Geologist William Ruddiman argues that the epoch began 5,000\u20138,000 years ago with the advent of agriculture and the buildup of early methane gasses (Ruddiman et al. 2008). Regardless of when the Anthropocene started, the major event that marks the boundary is the warming temperatures and mass extinction of nonhuman species caused by human activity (Figure 7.7). Researchers now declare that \u201chuman activity now rivals geologic forces in influencing the trajectory of the Earth System\u201d (Steffen et al. 2018, 1).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"299\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image1.jpg\" alt=\"Two cylindrical towers emitting white steam.\" width=\"299\" height=\"168\" \/> Figure 7.7: The Chooz Nuclear Power, in a valley in Ardennes, France, is a reminder that human activity affects the planet greatly. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Chooz_Nuclear_Power_Plant-9361.jpg\">Chooz Nuclear Power Plant-9361<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Raymond\">Raimond Spekking<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.[\/caption]\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossils: The Taphonomic Process<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Most of the evidence of human evolution comes from the study of the dead. To obtain as much information as possible from the remains of once-living creatures, one must understand the processes that occur after death. This is where <strong>[pb_glossary id=\"850\"]taphonomy[\/pb_glossary]<\/strong> comes in (Figure 7.8). Taphonomy is the study of what happens to an organism after death (Komar and Buikstra 2008, 189; Stodder 2008). It includes the study of how an organism becomes a fossil. However, as you\u2019ll see throughout this book, the majority of organisms never make it through the full fossilization process.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"261\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image25-1.jpg\" alt=\"Coyote skull with bones and fur.\" width=\"261\" height=\"348\" \/> Figure 7.8: Taphonomy focuses on what happens to the remains of an organism, like this coyote, after death. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Coyote remains (Figure 7.14)<\/a> by Sarah S. King is under a <a 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;\">Taphonomy is important in biological anthropology, especially in subdisciplines like bioarchaeology (the study of human remains in the archaeological record) and zooarchaeology (the study of faunal remains from archaeological sites). It is so important that many scientists have recreated a variety of burial and decay experiments to track taphonomic change in modern contexts. These contexts can then be used to understand the taphonomic patterns seen in the fossil record (see Reitz and Wing 1999, 122\u2013141).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taphonomic analysis can also give us important insights into the development of complex thought and ritual in human evolution. In Chapter 11, you will see the first evidence of recognized burial practices in hominins. Taphonomy helped to establish whether these burials were simply the result of natural processes or intentionally constructed by humans (Klein 1999, 395; Straus 1989). Deliberate burials often include the body placed in a specific position, such as supine (on the back) with arms crossed over the chest or in a flexed position (think fetal position) facing a particular direction. If bones have evidence of a carnivore or rodent gnawing on them, it can be inferred that the remains were exposed to scavengers after death.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Going back further in time, taphonomic evidence may tell us how our ancestors died. For instance, several australopithecine fossils show evidence of carnivore tooth marks and even punctures from saber-toothed cats, indicating that we weren\u2019t always the top of the food chain. The Bodo Cranium, a <em>Homo erectus<\/em> cranium from Middle Awash Valley, Ethiopia, shows cut marks made by stone tools, indicating an early example of possible defleshing activity in our human ancestors (White 1986). At the archaeological site of Zhoukoudian, researchers used taphonomy to show that the highly fragmented remains of at least 51 <em>Homo erectus<\/em> individuals were scavenged by Pleistocene cave hyenas (Boaz et al. 2004). The damage on Skull VI was described as \u201celongated, raking bite marks, isolated puncture bite marks, and perimortem breakage consistent with patterns of modern hyaenid bone modification\u201d (Boaz et al. 2004). Additionally, a fresh burnt equid cranium was discovered which supports the theory of mobile hominid scavenging and fire use at the site (Boaz et al. 2004).<\/p>\r\n\r\n<div class=\"textbox\">\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Special Topic: Bog Bodies and Mummies <span style=\"text-decoration: underline;\">(Add a picture to show how well preserved they are!)<\/span><\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Preservation is a key topic in anthropological research, since we can only study the evidence that gets left behind in the fossil and archaeological record. This chapter is concerned with the fossil record; however, there are other forms of preserved remains that provide anthropologists with information about the past. You\u2019ve undoubtedly heard of mummification, likely in the context of Egyptian or South American mummies. However, bog bodies and ice mummies are further examples of how remains can be preserved in special circumstances. It is important to note that fossilization is a process that takes much longer than the preservation of bog bodies or mummies.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Bog bodies are good examples of wetland preservation. Peat bogs are formed by the slow accumulation of vegetation and silts in ponds and lakes. Individuals were buried in bogs throughout Europe as far back as 10 kya, with a proliferation of activity from 1,600 to 3,200 years ago (Giles 2020; Ravn 2010). When they were found thousands of years later, they resembled recent burials. Their hair, skin, clothing, and organs were exceptionally well preserved, in addition to their bones and teeth (Eisenbeiss 2016; Ravn 2010). Preservation was so good in fact that archaeologists could identify the individuals\u2019 last meals and re-create tattoos found on their skin.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Extreme cold can also halt the natural decay process. A well-known ice mummy is \u00d6tzi, a Copper Age man dating to around 5,200 years ago found in the Alps (Vanzetti et al. 2012; Vidale et al. 2016). As with the bog bodies, his hair, skin, clothing, and organs were all well preserved. Recently, archaeologists were able to identify his last meal (Maixner et al. 2018). It was high in fat, which makes sense considering the extremely cold environment in which he lived, as meals high in fat assist in cold tolerance (Fumagalli et al. 2015).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">In the Andes, ancient peoples would bury human sacrifices throughout the high peaks in a sacred ritual called Capacocha (Wilson et al. 2007). The best-preserved mummy to date is called the \u201cMaiden\u201d or \u201cSarita\u201d because she was found at the summit of Sara Sara Volcano. Her remains are over 500 years old, but she still looks like the 15-year-old girl she was at the time of her death, as if she had just been sleeping for 500 years (Reinhard 2006).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Finally, arid environments can also contribute to the preservation of organic remains. As discussed with waterlogged sites, much of the bacteria that is active in breaking down bodies is already present in our gut and begins the putrefaction process shortly after death. Arid environments deplete organic material of the moisture that putrefactive bacteria need to function (Booth et al. 2015). When that occurs, the soft tissue like skin, hair, and organs can be preserved. It is similar to the way a food dehydrator works to preserve meat, fruit, and vegetables for long-term storage. There are several examples of arid environments spontaneously preserving human remains, including catacomb burials in Austria and Italy (Aufderheide 2003, 170, 192\u2013205).<\/p>\r\n\r\n<\/div>\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossilization<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossils only represent a tiny fraction of creatures that existed in the past. It is extremely difficult for an organism to become a fossil. After all, organisms are designed to deteriorate after they die. Bacteria, insects, scavengers, weather, and environment all aid in the process that breaks down organisms so their elements can be returned to Earth to maintain ecosystems (Stodder 2008). <strong>[pb_glossary id=\"852\"]Fossilization[\/pb_glossary]<\/strong>, therefore, is the preservation of an organism against these natural decay processes (Figure 7.9).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"699\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image20-2.png\" alt=\"Five images depicting fossilization.\" width=\"699\" height=\"345\" \/> Figure 7.9: A simplified illustration of the fossilization process beginning at an organism's death. In this example, the individual begins to decompose and then is covered by water and sediments, both protecting it and creating an environment for perimineralization. Sediments accumulate over time. Erosion eventually exposes the fossil, leading to its eventual discovery by paleoanthropologists. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Fossilization process (Figure 7.15)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">For fossilization to occur, several important things must happen. First, the organism must be protected from things like bacterial activity, scavengers, and temperature and moisture fluctuations. A stable environment is important. This means that the organism should not be exposed to significant fluctuations in temperature, humidity, and weather patterns. Changes to moisture and temperature cause the organic tissues to expand and contract repeatedly, which will eventually cause microfractures and break down (Stodder 2008). Soft tissue like organs, muscle, and skin are more easily broken down in the decay process; therefore, they are less likely to be preserved. Bones and teeth, however, last much longer and are more common in the fossil record (Williams 2004, 207).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wetlands are a particularly good area for preservation because they allow for rapid permanent burial and a stable moisture environment. That is why many fossils are found in and around ancient lakes and river systems. Waterlogged sites can also be naturally <strong>[pb_glossary id=\"854\"]anaerobic[\/pb_glossary]<\/strong> (without oxygen). Much of the bacteria that causes decay is already present in our gut and can begin the decomposition process shortly after death during putrefaction (Booth et al. 2015). Since oxygen is necessary for the body\u2019s bacteria to break down organic material, the decay process is significantly slowed or halted in anaerobic conditions.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The next step in the fossilization process is sediment accumulation. The sediments cover and protect the organism from the environment. They, along with water, provide the minerals that will eventually become the fossil (Williams 2004, 31). Sediment accumulation also provides the pressure needed for mineralization to take place. <strong>[pb_glossary id=\"856\"]Lithification[\/pb_glossary]<\/strong> is when the weight and pressure of the sediments squeeze out extra fluids and replace the voids that appear with minerals from the surrounding sediments. Finally, we have <strong>[pb_glossary id=\"858\"]permineralization[\/pb_glossary]<\/strong>. This is when the organism is fully replaced by minerals from the sediments. A fossil is really a mineral copy of the original organism (Williams 2004, 31).<\/p>\r\n\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Types of Fossils<\/strong><\/h3>\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Plants<\/em><\/h4>\r\n[caption id=\"\" align=\"alignleft\" width=\"259\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image2-1.jpg\" alt=\"Petrified wood.\" width=\"259\" height=\"194\" \/> Figure 7.10: An exquisite piece of petrified wood. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:PetrifiedWood.jpg\">PetrifiedWood<\/a> at the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Petrified_Forest_National_Park\">Petrified Forest National Park<\/a> by <a href=\"https:\/\/pdphoto.org\/\">Jon Sullivan<\/a> has been designated to the <a 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;\">Plants make up the majority of fossilized materials. One of the most common plants existing today, the fern, has been found in fossilized form many times. Other plants that no longer exist or the early ancestors of modern plants come in fossilized forms as well. It is through these fossils that we can discover how plants evolved and learn about the climate of Earth over different periods of time.<\/p>\r\nAnother type of fossilized plant is <strong>[pb_glossary id=\"860\"]petrified wood[\/pb_glossary]<\/strong>. This fossil is created when actual pieces of wood\u2014such as the trunk of a tree\u2014mineralize and turn into rock. Petrified wood is a combination of silica, calcite, and quartz, and it is both heavy and brittle. Petrified wood can be colorful and is generally aesthetically pleasing because all the features of the original tree\u2019s composition are illuminated through mineralization (Figure 7.10). There are a number of places all over the world where petrified wood \u201cforests\u201d can be found, but there is an excellent assemblage in Arizona, at the Petrified Forest National Park. At this site, evidence relating to the environment of the area some 225 <strong>[pb_glossary id=\"862\"]mya[\/pb_glossary]<\/strong> is on display.\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Human\/Animal Remains<\/em><\/h4>\r\n[caption id=\"\" align=\"alignright\" width=\"242\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image7-1.jpg\" alt=\"Partial hominin skeleton on black background.\" width=\"242\" height=\"583\" \/> Figure 7.11: \u201cLucy\u201d (AL 288-1), Australopithecus afarensis. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Lucy_blackbg.jpg\">Lucy blackbg<\/a> by 120 is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/2.5\/deed.en\">CC BY 2.5 License<\/a>.[\/caption]\r\n\r\nWe are more familiar with the fossils of early animals because natural history museums have exhibits of dinosaurs and extinct mammals. However, there are a number of fossilized hominin remains that provide a picture of the fossil record over the course of our evolution from primates. The term <strong>[pb_glossary id=\"800\"]hominins[\/pb_glossary]<\/strong> includes all human ancestors who existed after the evolutionary split from chimpanzees and bonobos, some six to seven mya. Modern humans are <em>Homo sapiens<\/em>, but hominins can include much earlier versions of humans. One such hominin is \u201cLucy\u201d (AL 288-1), the 3.2 million-year-old fossil of <em>Australopithecus afarensis<\/em> that was discovered in Ethiopia in 1974 (Figure 7.11). Until recently, Lucy was the most complete and oldest hominin fossil, with 40% of her skeleton preserved (see Chapter 9 for more information about Lucy). In 1994, an <em>Australopithecus<\/em> fossil nicknamed \u201cLittle Foot\u201d (Stw 573) was located in the World Heritage Site at Sterkfontein Caves (\u201cthe Cradle of Humankind\u201d) in South Africa. Little Foot is more complete than Lucy and possibly the oldest fossil that has so far been found, dating to at least 3.6 million years (Granger et al. 2015). The ankle bones of the fossil were extricated from the matrix of concrete-like rock, revealing that the bones of the ankles and feet indicate bipedalism (University of Witwatersrand 2017).\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Both the Lucy and Little Foot fossils date back to the Pliocene (5.8 to 2.3 mya). Older hominin fossils from the late Miocene (7.25 to 5.5 mya) have been located, although they are much less complete. The oldest hominin fossil is a fragmentary skull named <em>Sahelanthropus tchadensis<\/em>, found in Northern Chad and dating to circa seven mya (Lebatard et al. 2008). It is through the discovery, dating, and study of primate and early hominin fossils that we find physical evidence of the evolutionary timeline of humans.<\/p>\r\n\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Asphalt<\/em><\/h4>\r\n[caption id=\"\" align=\"aligncenter\" width=\"510\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image28.jpg\" alt=\"Asphalt lake with mammoth figurines.\" width=\"510\" height=\"340\" \/> Figure 7.12: This is a recreation of how animals tragically came to be trapped in the asphalt lake at the La Brea Tar Pits. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Mammoth_Tragedy_at_La_Brea_Tar_Pits_(5463657162).jpg\">Mammoth Tragedy at La Brea Tar Pits (5463657162)<\/a> by <a href=\"https:\/\/www.flickr.com\/people\/81943113@N00\">KimonBerlin<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/2.0\/legalcode\">CC BY-SA 2.0 License<\/a>.[\/caption]\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"206\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image6-3.jpg\" alt=\"Skull with open jaw and large teeth.\" width=\"206\" height=\"245\" \/> Figure 7.13: The fearsome jaws of the saber-toothed cat (Smilodon fatalis) found at the La Brea Tar Pits. Credit: <a href=\"https:\/\/www.flickr.com\/photos\/jsjgeology\/15256884929\">Smilodon saber-toothed tiger skull (La Brea Asphalt, Upper Pleistocene; Rancho La Brea tar pits, southern California, USA) 1<\/a> by <a href=\"https:\/\/www.flickr.com\/photos\/jsjgeology\/\">James St. John<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/2.0\/\">CC BY 2.0 License<\/a>.[\/caption]\r\n\r\nAsphalt, a form of crude oil, can also yield fossilized remains. Asphalt is commonly referred to in error as tar because of its viscous nature and dark color. A famous fossil site from California is La Brea Tar Pits in downtown Los Angeles (Figure 7.12). In the middle of the busy city on Wilshire Boulevard, asphalt (not tar) bubbles up through seeps (cracks) in the sidewalk. The La Brea Tar Pits Museum provides an incredible look at the both extinct and extant animals that lived in the Los Angeles Basin 40,000\u201311,000 years ago. These animals became entrapped in the asphalt during the Pleistocene and perished in place. Ongoing excavations have yielded millions of fossils, including <strong>[pb_glossary id=\"864\"]megafauna[\/pb_glossary]<\/strong> such as American mastodons and incomplete skeletons of extinct species of dire wolves, <em>Canis dirus<\/em>, and the saber-toothed cat, <em>Smilodon fatalis<\/em> (Figure 7.13). Fossilized remains of plants have also been found in the asphalt. The remains of one person have also been found at the tar pits. Referred to as La Brea Woman, the remains were found in 1914 and were subsequently dated to around 10,250 years ago. The La Brea Woman was a likely female individual who was 17\u201328 years old at the time of her death, with a height of under five feet (Spray 2022). She is thought to have died from blunt force trauma to her head, famously making her Los Angeles\u2019s first documented homicide victim (Spray 2022). (Learn more about her in the Special Topic box, \u201cNecropolitics,\u201d below.) Between the fossils of animals and those of plants, paleontologists have a good idea of the way the Los Angeles Basin looked and what the climate in the area was like many thousands of years ago.\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Igneous Rock<\/em><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Most fossils are found in sedimentary rock. This type of rock has been formed from deposits of minerals over millions of years in bodies of water on Earth\u2019s surface. Some examples include shale, limestone, and siltstone. Sedimentary rock typically has a layered appearance. However, fossils have been found in igneous rock as well. Igneous rock is volcanic rock that is created from cooled molten lava. It is rare for fossils to survive molten lava, and it is estimated that only 2% of all fossils have been found in igneous rock (Ingber 2012). Part of a giant rhinocerotid skull dating back 9.2 mya to the Miocene was discovered in Cappadocia, Turkey, in 2010. The fossil was a remarkable find because the eruption of the \u00c7ardak caldera was so sudden that it simply dehydrated and \u201cbaked\u201d the animal (Antoine et al. 2012).<\/p>\r\n\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Trace Fossils<\/em><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Depending on the specific circumstances of weather and time, even footprints can become fossilized. Footprints fall into the category of <strong>[pb_glossary id=\"866\"]trace fossils[\/pb_glossary]<\/strong>, which includes other evidence of biological activity such as nests, burrows, tooth marks, and shells. A well-known example of trace fossils are the Laetoli footprints in Tanzania (Figure 7.14). More recently, archaeological investigations in North America have revealed fossil footprints which rewrite the history of people in the Americas at White Sands, New Mexico. You can read more about the Laetoli and White Sands footprints in the Dig Deeper box below.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"399\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image5-2.jpg\" alt=\"Uneven rock surface with footprints. \" width=\"399\" height=\"245\" \/> Figure 7.14: A few early hominin footprints fossilized at Laetoli. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:NHM_-_Laetoli_Fu%C3%9Fspuren.jpg\">NHM - Laetoli Fu\u00dfspuren<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Xenophon\">Wolfgang Sauber<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Other fossilized footprints have been discovered around the world. At Pech Merle cave in the Dordogne region of France, archaeologists discovered two fossilized footprints. They then brought in indigenous trackers from Namibia to look for other footprints. The approach worked, as many other footprints belonging to as many as five individuals were discovered with the expert eyes of the trackers (Pastoors et al. 2017). These footprints date back 12,000 years (Granger Historical Picture Archive 2018).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Some of the more unappealing but still-fascinating trace fossils are bezoars and coprolite. <strong>[pb_glossary id=\"868\"]Bezoars[\/pb_glossary]<\/strong> are hard, concrete-like substances found in the intestines of fossilized creatures. Bezoars start off like the hair balls that cats and rabbits accumulate from grooming, but they become hard, concrete-like substances in the intestines. If an animal with a hairball dies before expelling the hair ball mass <em>and <\/em>the organism becomes fossilized, that mass becomes a bezoar.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"870\"]Coprolite[\/pb_glossary]<\/strong> is fossilized dung. One of the best collections of coprolites is affectionately known as the \u201cPoozeum.\u201d The collection includes a huge coprolite named \u201cPrecious\u201d (Figure 7.15). Coprolite, like all fossilized materials, can be <strong>[pb_glossary id=\"872\"]in matrix[\/pb_glossary]<\/strong>\u2014meaning that the fossil is embedded in secondary rock. As unpleasant as it may seem to work with coprolites, remember that the organic material in dung has mineralized or has started to mineralize; therefore, it is no longer soft and is generally not smelly. Also, just as a doctor can tell a lot about health and diet from a stool sample, anthropologists can glean a great deal of information from coprolite about the diets of ancient animals and the environment in which the food sources existed. For instance, 65 million-year-old grass <em>phytoliths<\/em> (microscopic silica in plants) found in dinosaur coprolite in India revealed that grasses had been in existence much earlier than scientists initially believed (Taylor and O\u2019Dea 2014, 133).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"312\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image19-1-1.jpg\" alt=\"Piece of fossilized poop.\" width=\"312\" height=\"224\" \/> Figure 7.15: An extremely large coprolite named \u201cPrecious.\u201d Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Precious_the_Coprolite_Courtesy_of_the_Poozeum.jpg\">Precious the Coprolite Courtesy of the Poozeum<\/a> by <a href=\"https:\/\/poozeum.com\">Poozeum<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.[\/caption]\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Pseudofossils<\/em><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"874\"]Pseudofossils[\/pb_glossary]<\/strong> are not to be mistaken for fake fossils, which have vexed scientists from time to time. A fake fossil is an item that is deliberately manipulated or manufactured to mislead scientists and the general public. In contrast, pseudofossils are not misrepresentations but rather misinterpretations of rocks that look like true fossilized remains (S. Brubaker, personal communication, March 9, 2018). Pseudofossils are the result of impressions or markings on rock, or even the way other inorganic materials react with the rock. A common example is dendrites, the crystallized deposits of black minerals that resemble plant growth (Figure 7.16). Other examples of pseudofossils are unusual or odd-shaped rocks that include various concretions and nodules. An expert can examine a potential fossil to see if there is the requisite internal structure of organic material such as bone or wood that would qualify the item as a fossil.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"426\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image29.jpg\" alt=\"Rock with black branching fractal veins.\" width=\"426\" height=\"284\" \/> Figure 7.16: A beautiful example of dendrites, a type of pseudofossil. It\u2019s easy to see how the black crystals look like plant growth. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Dendrites (Figure 7.25)<\/a> from the <a href=\"https:\/\/maturango.org\/\">Maturango Museum<\/a>, Ridgecrest, California, by Sarah S. King and Lee Anne Zajicek is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\n<div class=\"textbox shaded\">\r\n<h2 class=\"import-Normal\">Dig Deeper: <del>Trace Fossils<\/del>\u00a0<em>The Power of Poop<\/em><\/h2>\r\n<p class=\"import-Normal\">Coprolites found in Paisley Caves, Oregon, in the United States are shedding new light on some of the earliest occupants in North America. Human coprolites are distinguished from animal coprolites through the identification of fecal biomarkers using lipids, or fats, and bile acids (Shillito et al. 2020a). Paisley Caves have 16,000 years of anthropogenic, or human-caused, deposition, with some coprolites having been dated as old as 12.8kya (Blong et al. 2020). Over 285 radiocarbon dates have been recorded from the site (Shillito et al. 2020a), making Paisley Caves one of the most well-dated archaeological sites in the United States. Coprolite analysis can be summarized in three levels, macroscopic, microscopic, and molecular. This can also be understood as analyzing the morphology (macroscopic), contents (microscopic), and residues (molecular) (Shillito et al. 2020b). Each of these levels adds a different layer of information. Coprolite shape is informative through what can be seen macroscopically, such as ingestions of basketry or cordage, small gravels and grains, and general shape. The contents of coprolites may be of the most interest to scientists because certain plants and animals can signal past environments as well as food procurement methods. Coprolites from Paisley Caves have included small pebbles and obsidian chips from butchering game, grinding plants, and general food preparation as well as small bits of fire cracked rock likely from cooking in hearths (Blong 2020). Additionally, rodent bones in coprolites included crania and vertebrae, which suggests whole consumption (Taylor et al. 2020). Insect remains are present in the coprolites as well, such as ants, Jerusalem crickets, June beetles, and darkling beetles (Blong 2020). In all, the coprolites of Paisley Caves have provided an invaluable resource to anthropologists to study the past climate and lifeways of early humans in the Americas.<\/p>\r\n<p class=\"import-Normal\">Coprolites can also signal past health, which is a study known as paleopathology. A study by Katelyn McDonough and colleagues (2022) focused on the identification of parasites in coprolites at Bonneville Estates Rockshelter in eastern Nevada and their link to the greater Great Basin during the Archaic, a period of time spanning 8,000\u20135,000 years ago. According to the study, parasites such as Acanthocephalans (thorny-headed worms) have been affecting the Great Basin for at least the last 10,000 years. Acanthocephalans are endoparasites, meaning parasites that live inside of their hosts. They are found worldwide and seem to have been concentrated in the Great Basin in the past. Bonneville Estates Rockshelter has been visited by humans for over 13,000 years, with parasite identification going back to nearly 7,000 years. The species identified at Bonneville Estates is <em>Moniliformis clarki<\/em>. This species parasitizes crickets and insects, a popular food source during the Archaic in the Great Basin. The parasite uses intermediate hosts to get to mammals and birds as definitive hosts. Crickets and beetles have been recorded as food materials in Paisley Caves as well. Insects have remained an important dietary staple for people of the Great Basin and are consumed raw, dried, brined, or ground into flour. Insects that remain uncooked or undercooked have a higher risk for transmission of parasites. Symptoms associated with Acanthocephalans infection are intense intestinal discomfort, anemia, and anorexia, leading to death. It is hypothesized that the consumption of basketry, cordage, and charcoal (which was also identified at Paisley Caves), sometimes associated with parasite-infected coprolites, may have been a method of treatment for the infection. Interestingly, present day infections from this parasite are rising after remaining quite rare, as detection of the parasite is occurring in insect farms.<\/p>\r\n\r\n<\/div>\r\n<h4 class=\"import-Normal\"><em>Walking to the Past<\/em><\/h4>\r\n<p class=\"import-Normal\">In 1974, British anthropologist Mary Leakey discovered fossilized animal tracks at Laetoli (Figure 7.17), not far from the important paleoanthropological site at Olduvai Gorge in Tanzania. A few years later, a 27-meter trail of hominin footprints were discovered at the same site. These 70 footprints, now referred to as the Laetoli Footprints, were created when early humans walked in wet volcanic ash. Before the impressions were obscured, more volcanic ash and rain fell, sealing the footprints. These series of environmental events were truly extraordinary, but they fortunately resulted in some of the most famous and revealing trace fossils ever found. Dating of the footprints indicate that they were made 3.6 mya (Smithsonian National Museum of Natural History 2018).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"495\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image13-1-1.png\" alt=\"Eastern Africa map shows sites within Tanzania.\" width=\"495\" height=\"382\" \/> Figure 7.17: Location of Laetoli site in Tanzania, Africa, with Olduvai Gorge nearby. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Laetoli and Olduvai Gorge sites (Figure 7.26)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\">Just as forensic scientists can use footprints to identify the approximate build of a potential suspect in a crime, archaeologists have read the Laetoli Footprints for clues to these early humans. The footprints clearly indicate bipedal hominins who had similar feet to those of modern humans. Analysis of the gait through computer simulation revealed that the hominins at Laetoli walked similarly to the way we walk today (Crompton 2012). More recent analyses confirm the similarity to modern humans but also indicate a gait that involved more of a flexed limb than that of modern humans (Hatala et al. 2016; Raichlen and Gordon 2017). The relatively short stride implies that these hominins had short legs\u2014unlike the longer legs of later early humans who migrated out of Africa (Smithsonian National Museum of Natural History 2018). In the context of Olduvai Gorge, where fossils of <em>Australopithecus afarensis<\/em> have been located and dated to the same timeframe as the footprints, it is likely that these newly discovered impressions were left by these same hominins.<\/p>\r\n<p class=\"import-Normal\">The footprints at Laetoli were made by a small group of as many as three <em>Australopithecus afarensis<\/em>, walking in close proximity, not unlike what we would see on a modern street or sidewalk. Two trails of footprints have been positively identified with the third set of prints appearing smaller and set in the tracks left by one of the larger individuals. While scientific methods have given us the ability to date the footprints and understand the body mechanics of the hominin, additional consideration of the footprints can lead to other implications. For instance, the close proximity of the individuals implies a close relationship existed between them, not unlike that of a family. Due to the size variation and the depth of impression, the footprints seem to have been made by two larger adults and possibly one child. Scientists theorize that the weight being carried by one of the larger individuals is a young child or a baby (Masao et al. 2016). Excavation continues at Laetoli today, resulting in the discovery of two more footprints in 2015, also believed to have been made by <em>Au. afarensis<\/em> (Masao et al. 2016).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"482\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image10.jpg\" alt=\"Map shows Tularosa Basin.\" width=\"482\" height=\"331\" \/> Figure 7.18: Tularosa Basin, New Mexico. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:HUC1305.jpg\">Map of Tularosa Basin<\/a> by the <a href=\"https:\/\/www.usgs.gov\/\">United States Geological Survey<\/a> is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n\r\nBut it is not just human evolution studies that can benefit from the analysis of fossil footprints. A recent discovery of fossilized footprints has rewritten what we know about the peopling of the Americas. It was originally thought that humans had been in the Americas for at least the last 15,000 years by crossing through the ice-free corridor (IFC) between the Cordilleran and Laurentide ice sheets in present-day Alaska and Canada. However, fossil footprints from the Tularosa Basin of New Mexico (see Figure 7.18) discovered in 2021 have challenged this theory. The footprints, dated between 22,860 (\u2213320) and 21,130 (\u2213250) years ago (nps.gov) based on <em>Ruppia cirrhosa <\/em>grass seeds located above and below the footprints, have shown humans have been in the Americas for much longer than previously thought. These footprints represent an adolescent individual and toddler walking through the lakebed at White Sands (see Figure 7.19), New Mexico, alongside both giant ground sloths and mammoths (Barras 2022; Wade 2021). Also present in the lakebed are footprints of camels and dire wolves (nps.gov 2022; Wade 2021).\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"789\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image31-1.png\" alt=\"Archaeologists on ground. Excavation with footprints. Closeups of footprints.\" width=\"789\" height=\"594\" \/> Figure 7.19: Excavation of fossil footprints from New Mexico. Credit: <a href=\"https:\/\/www.usgs.gov\/programs\/climate-research-and-development-program\/news\/discovery-ancient-human-footprints-white\">Images of White Sands National Park Study Site Footprints<\/a> by the <a href=\"https:\/\/www.usgs.gov\/programs\/climate-research-and-development-program\">USGS Climate Research and Development Program<\/a> is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.[\/caption]\r\n<p class=\"import-Normal\">The IFC model was upheld by a group of theorists known as \u201cClovis First,\u201d who believed the migration of people into the Americas was recent and was represented archaeologically through the Clovis projectile point toolkit. Subsequent discoveries at sites such as Cactus Hill on the east coast of the United States and Monte Verde, Chile, have demonstrated that this model wouldn\u2019t have worked. Because these sites are as old as 20,000 years and 18,500 years respectively, the IFC would have been frozen over and impassable (Gruhn 2020). Other models have been adopted to account for this, such as the coastal migration model down the west coast of North America. The more-likely migration scenario seems to be neither of these as more discoveries or antiquity continue to emerge. People may instead have migrated into the Americas before the last glacial maximum began, around 25,500\u201319,000 years ago. According to Indigenous knowledge, they have always been here. With the discovery of the White Sands footprints, it is known that humans have been in the Americas for at least 20,000 years.<\/p>\r\n<p class=\"import-Normal\">This discovery also reveals the importance of recognizing knowledge beyond that which is produced by the European scientific tradition. Rather than framing science in a way that runs counter to Indigenous knowledge, it can be thought that science is catching up with it. <span style=\"background-color: #00ffff;\">For instance, the Acoma Pueblo people have the word for <em>camel<\/em> in their vocabulary.<\/span> This was dismissed by scientists who assumed the word was for describing camels that were introduced to the United States in the past 100 years. However, the discovery of the White Sands footprints also included the footprints of Pleistocene camels in the same strata. Therefore, the fact that the Acoma Pueblo people have had a word for <em>camel<\/em> likely refers the Pleistocene-age megafauna camel, <em>Camelops hesternus,<\/em> rather than <em>Camelus dromedarius<\/em> or <em>Camelus bactrianus<\/em>, two present-day camel species (which are actually descendants of <em>Camelops hesternus<\/em>). Therefore, the existence of the Acoma Pueblo word for <em>camel <\/em>is not like an anomaly but rather a testament to the fact that Acoma Pueblo ancestors walked beside <em>C. hesternus<\/em> on this continent 20,000 years ago. These footprints challenge the \u201cice-free corridor\u201d expansion model, as the bridge connecting present-day Alaska and Russia into Canada would have been covered in an impenetrable ice sheet at this time. The discovery of these footprints urges scientists to reconsider further investigations at well-known Terminal Pleistocene\/Early Holocene dry lake beds in the Southwestern and Mojave deserts\u2014and to include Indigenous knowledge in their work rather than ignore it.<\/p>\r\n\r\n<div class=\"textbox\">\r\n<h2 class=\"import-Normal\">Special Topic: Necropolitics<\/h2>\r\n<p class=\"import-Normal\">What are necropolitics? Necropolitics is an application of critical theory that describes how \u201cgovernments assign differential value to human life\u201d and similarly how someone is treated after they die (Verghese 2021). How is someone\u2019s death political?<\/p>\r\n<p class=\"import-Normal\">Consider the La Brea Woman example from the section on asphalt above. The La Brea Woman\u2019s discovery was controversial, not because she is the only person to be found in the tar pits or because of her age but also because of necropolitics. The La Brea Woman was collected in 1914 and her body was housed on display at the George C. Page Museum in Los Angeles against the wishes of the Chumash and the Tongva, two tribes whose ancestral lands include Los Angeles. The museum decided to display a skull cast instead to meet the request of the tribes which included a separate postcranial skeleton from a different individual. The updated display itself was wrought with other ethical issues, as a cast of her skull was \u201cattached to the ancient remains of a Pakistani female that was dyed dark bronze, the femurs shortened to approximate the stature of native people\u201d (Cooper 2010). In both cases, neither the individuals or their descendent communities consented to the display or grotesque modification of human remains. According to an interview conducted by LA Weekly (Cooper 2010) with Cindi Alvitre, former chair of the Gabrielino-Tongva Tribal Council, the display of Indigenous human remains is akin to voyeurism. She states \u201cIt's disheartening to me because it's very inappropriate to display any human remains. The things we do to fill the imagination of visitors. It violates human rights.\u201d It is important to listen to the wishes of Indigenous people and center their values when conducting work with their ancestors. A good source for considering places to look for archaeological research ethics before conducting fieldwork (and ideally during your research design) is the Society for American Archaeology\u2019s ethics principle list, as well as following the Indigenous Archaeology Collective.<\/p>\r\n<p class=\"import-Normal\">Indigenous remains are now protected in the United States due to legislation such as Native American Graves Protection and Repatriation Act (NAGPRA). You can read more about this in Chapter 15: Bioarchaeology and Forensic Anthropology. Before the passing of NAGPRA, tribes had little agency over how the bodies of their ancestors were treated by anthropologists and museums, including decisions about sampling and destructive tests. Now when archaeological field work is conducted on federal land, tribes must be consulted before work begins. This consultation process often includes what to do if human remains are encountered. Indigenous tribes are multifaceted and multivocal; each has its own rules about how to handle the remains of their ancestors. In some cases, all work on the project must be halted after the discovery of human remains. Other tribes allow for work to continue if the remains are moved and reburied. Some tribes are open to radiometric dating if it aligns with their beliefs in the afterlife. Each tribe is different, and each tribe deserves to have its wishes respected.<\/p>\r\n\r\n<\/div>\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Voices From the Past: What Fossils Can Tell Us<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Given that so few organisms ever become fossilized, any anthropologist or fossil hunter will tell you that finding a fossil is extremely exciting. But this is just the beginning of a fantastic mystery. With the creative application of scientific methods and deductive reasoning, a great deal can be learned about the fossilized organism and the environment in which it lived, leading to enhanced understanding of the world around us.<\/p>\r\n\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ccffcc;\"><strong>Dating Methods<\/strong><\/span><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Context is a crucial concept in paleoanthropology and archaeology. Objects and fossils are interesting in and of themselves, but without context there is only so much we can learn from them. One of the most important contextual pieces is the dating of an object or fossil. By being able to place it in time, we can compare it more accurately with other contemporary fossils and artifacts or we can better analyze the evolution of a fossil species or artifacts. To answer the question \u201cHow do we know what we know?,\u201d you have to know how archaeologists and paleoanthropologists establish dates for artifacts, fossils, and sites.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Though accurate dating is important for context and analysis, we must consider the impact. Many of the chronometric dating methods used by anthropologists require the removal of small samples from artifacts, bones, soils, and rock. Thus these techniques are considered destructive. How much of an artifact are you willing to destroy to get your date? Sharon Clough, a Senior Environmental Officer at Cotswold Archaeology, addressed this issue in a case study from her research. She stated that \u201cthe benefit of a date did not outweigh the destruction of a valuable and finite resource\u201d (Clough 2020). The resource in question was human remains. When considering our dating options, we want to be sure that we do as little harm as possible, especially in the case of human remains (read more about this issue in the Special Topic box, \u201cNecropolitics\u201d).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dating techniques are divided into two broad categories: relative dating methods and chronometric (sometimes called absolute) dating methods.<\/p>\r\n\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ccffcc;\"><em>Relative Dating<\/em><\/span><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"876\"]Relative dating[\/pb_glossary]<\/strong> methods are used first because they rely on simple observational skills. In the 1820s, Christian J\u00fcrgensen Thomsen at the National Museum of Denmark in Copenhagen developed the \u201cthree-age\u201d system still used in European archaeology today (Feder 2017, 17). He categorized the artifacts at the museum based on the idea that simpler tools and materials were most likely older than more complex tools and materials. Stone tools must predate metal tools because they do not require special technology to develop. Copper and bronze tools must predate iron because they can be smelted or worked at lower temperatures, etc. Based on these observations, he categorized the artifacts into Stone Age, Bronze Age, and Iron Age.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The restriction of relative dating is that you don\u2019t know specific dates or how much time passed between different sites or artifacts. You simply know that one artifact or fossil is older than another. Thomsen knew that Stone Age artifacts were older than Bronze Age artifacts, but he couldn\u2019t tell if they were hundreds of years older or thousands of years older. The same is true with fossils that have differences of ages into the hundreds of millions of years.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The first relative dating technique is <strong>[pb_glossary id=\"878\"]stratigraphy[\/pb_glossary] <\/strong>(Figure 7.20). You might have already heard this term if you have watched documentaries on archaeological excavations. That\u2019s because this method is still being used today. It provides a solid foundation for other dating techniques and gives important context to artifacts and fossils found at a site.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"382\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image11-1.png\" alt=\"Stratigraphic cross-section with 12 strata.\" width=\"382\" height=\"662\" \/> Figure 7.20: An illustration of a stratigraphic cross-section. The objects at a lower strata are older than the one above. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Stratigraphic cross-section (Figure 7.28)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">Stratigraphy is based on the <strong>[pb_glossary id=\"880\"]Law of Superposition[\/pb_glossary]<\/strong> first proposed by Nicholas Steno in 1669 and further explored by James Hutton (the previously mentioned \u201cFather\u201d of Deep Time). Essentially, superposition tells us that things on the bottom are older than things on the top (Williams 2004, 28). Notice on Figure 7.20 that there are distinctive layers piled on top of each other. It stands to reason that each layer is older than the one immediately on top of it (Hester et al. 1997, 338). Think of a pile of laundry on the floor. Over the course of a week, as dirty clothes get tossed on that pile, the shirt tossed down on Monday will be at the bottom of the pile while the shirt tossed down on Friday will be at the top. Assuming that the laundry pile was undisturbed throughout the week, if the clothes were picked up layer by layer, the clothing choices that week could be reconstructed in the order that they were worn.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Another relative dating technique is <strong>[pb_glossary id=\"882\"]biostratigraphy[\/pb_glossary]<\/strong>. This form of dating looks at the context of a fossil or artifact and compares it to the other fossils and biological remains (plant and animal) found in the same stratigraphic layers. For instance, if an artifact is found in the same layer as wooly mammoth remains, you know that it must date to around the last ice age, when wooly mammoths were still abundant on Earth. In the absence of more specific dating techniques, early archaeologists could prove the great antiquity of stone tools because of their association with extinct animals. The application of this relative dating technique in archaeology was used at the Folsom site in New Mexico. In 1927, a stone spear point was discovered embedded in the rib of an extinct species of bison. Because of the undeniable association between the artifact and the ancient animal, there was scientific evidence that people had occupied the North American continent since antiquity (Cook 1928).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Similar to biostratigraphic dating is <strong>[pb_glossary id=\"884\"]cultural dating[\/pb_glossary] <\/strong>(Figure 7.21). This relative dating technique is used to identify the chronological relationships between human-made artifacts. Cultural dating is based on artifact types and styles (Hester et al. 1997, 338). For instance, a pocket knife by itself is difficult to date. However, if the same pocket knife is discovered surrounded by cassette tapes and VHS tapes, it is logical to assume that the artifact came from the late 20th century like the cassette and VHS tapes. The pocket knife could not be dated earlier than the late 20th century because the tapes were made no earlier than 1977. In the Thomsen example above, he was able to identify a relative chronology of ancient European tools based on the artifact styles, manufacturing techniques, and raw materials. Cultural dating can be used with any human-made artifacts. Both cultural dating and biostratigraphy are most effective when researchers are already familiar with the time periods for the artifacts and animals. They are still used today to identify general time periods for sites.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"364\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image26-1.png\" alt=\"Ax heads, swords, circlets, and pots by type.\" width=\"364\" height=\"557\" \/> Figure 7.21: Charts of typology, like these representing items from the Bronze Age, are used to classify artifacts and illustrate cultural material assemblages. Credit: <a href=\"https:\/\/wellcomecollection.org\/works\/de5rxx5a\">Bronze Age implements, ornaments and pottery (Period II)<\/a> by <a href=\"https:\/\/wellcomecollection.org\/\">Wellcome Collection<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/#_ga=2.5144115.1054155377.1564173886-467226638.1563307053\">CC BY 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Chemical dating was developed in the 19th century and represents one of the early attempts to use soil composition and chemistry to date artifacts. A specific type of chemical dating is <strong>[pb_glossary id=\"886\"]fluorine dating[\/pb_glossary]<\/strong>, and it is commonly used to compare the age of the soil around bone, antler, and teeth located in close proximity (Cook and Ezra-Cohn 1959; Goodrum and Olson 2009). While this technique is based on chemical dating, it only provides the relative dates of items rather than their absolute ages. For this reason, fluorine dating is considered a hybrid form of relative and chronometric dating methods (which will be discussed next).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Soils contain different amounts of chemicals, and those chemicals, such as fluorine, can be absorbed by human and animal bones buried in the soil. The longer the remains are in the soil, the more fluorine they will absorb (Cook and Ezra-Cohn 1959; Goodrum and Olson 2009). A sample of the bone or antler can be processed and measured for its fluorine content. Unfortunately, this absorption rate is highly sensitive to temperature, soil pH, and varying fluorine levels in local soil and groundwater (Goodrum and Olson 2009; Haddy and Hanson 1982). This makes it difficult to get an accurate date for the remains or to compare remains between two sites. However, this technique is particularly useful for determining whether different artifacts come from the same burial context. If they were buried in the same soil for the same length of time, their fluorine signatures would match.<\/p>\r\n\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ccffcc;\"><em>Chronometric Dating<\/em><\/span><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Unlike relative dating methods, <strong>[pb_glossary id=\"888\"]chronometric dating[\/pb_glossary]<\/strong> methods provide specific dates and time ranges. Many of the chronometric techniques we will discuss are based on work in other disciplines such as chemistry and physics. The modern developments in studying radioactive materials are accurate and precise in establishing dates for ancient sites and remains.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Many of the chronometric dating methods are based on the measurement of radioactive decay of particular elements. <strong>[pb_glossary id=\"890\"]Elements[\/pb_glossary]<\/strong> are materials that cannot be broken down into more simple materials without losing their chemical identity (Brown et al. 2018, 48). Each element consists of an <strong>[pb_glossary id=\"892\"]atom[\/pb_glossary]<\/strong> that has a specific number of protons (positively charged particles) and electrons (negatively charged particles) as well as varying numbers of neutrons (particles with no charge). The protons and neutrons are located in the densely compacted nucleus of the atom, but the majority of the volume of an atom is space outside the nucleus around which the electrons orbit (see Figure 7.22).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"285\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image18-1-1.png\" alt=\"Atom labeled with nucleus, proton, neutron, and electron.\" width=\"285\" height=\"285\" \/> Figure 7.22: Simplified illustration of an atom. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Atom%20Diagram.svg\">Atom Diagram<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:AG_Caesar\">AG Caesar<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Elements are classified based on the number of protons in the nucleus. For example, carbon has six protons, giving it an atomic number 6. Uranium has 92 protons, which means that it has an atomic number 92. While the number of protons in the atom of an element do not vary, the number of neutrons may. Atoms of a given element that have different numbers of neutrons are known as <strong>[pb_glossary id=\"894\"]isotopes[\/pb_glossary]<\/strong>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The majority of an atom\u2019s mass is determined by the protons and neutrons, which have more than a thousand times the mass of an electron. Due to the different numbers of neutrons in the nucleus, isotopes vary by nuclear\/atomic weight (Brown et al. 2018, 94). For instance, isotopes of carbon include carbon 12 (<sup>12<\/sup>C), carbon 13 (<sup>13<\/sup>C), and carbon 14 (<sup>14<\/sup>C). Carbon always has six protons, but <sup>12<\/sup>C has six neutrons whereas <sup>14<\/sup>C has eight neutrons. Because <sup>14<\/sup>C has more neutrons, it has a greater mass than <sup>12<\/sup>C (Brown et al. 2018, 95).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Most isotopes in nature are considered <strong>[pb_glossary id=\"896\"]stable isotopes[\/pb_glossary]<\/strong> and will remain in their normal structure indefinitely. However, some isotopes are considered <strong>[pb_glossary id=\"898\"]unstable isotopes[\/pb_glossary]<\/strong> (sometimes called radioisotopes) because they spontaneously release energy and particles, transforming into stable isotopes (Brown et al. 2018, 946; Flowers et al. 2018, section 21.1). The process of transforming the atom by spontaneously releasing energy is called <strong>[pb_glossary id=\"900\"]radioactive decay[\/pb_glossary]<\/strong>. This change occurs at a predictable rate for nearly all radioisotopes of elements, allowing scientists to use unstable isotopes to measure time passage from a few hundred to a few billion years with a large degree of accuracy and precision.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The leading chronometric method for archaeology is <strong>[pb_glossary id=\"902\"]radiocarbon dating[\/pb_glossary] <\/strong>(Figure 7.23). This method is based on the decay of <sup>14<\/sup>C, which is an unstable isotope of carbon. It is created when nitrogen 14 (<sup>14<\/sup>N) interacts with cosmic rays, which causes it to capture a neutron and convert to <sup>14<\/sup>C. Carbon 14 in our atmosphere is absorbed by plants during photosynthesis, a process by which light energy is turned into chemical energy to sustain life in plants, algae, and some bacteria. Plants absorb carbon dioxide from the atmosphere and use the energy from light to convert it into sugar that fuels the plant (Campbell and Reece 2005, 181\u2013200). Though <sup>14<\/sup>C is an unstable isotope, plants can use it in the same way that they use the stable isotopes of carbon.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"514\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image27.png\" alt=\"Creation of Carbon 14.\" width=\"514\" height=\"658\" \/> Figure 7.23: A graphic illustrating how 14C is created in the atmosphere, is absorbed by living organisms, and ends up in the archaeological record. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Radiocarbon dating (Figure 7.32)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">Animals get <sup>14<\/sup>C by eating the plants. Humans take it in by eating plants and animals. After death, organisms stop taking in new carbon, and the unstable <sup>14<\/sup>C will begin to decay. Carbon 14 has a half-life of 5,730 years (Hester et al. 1997, 324). That means that in 5,730 years, half the amount of <sup>14<\/sup>C will convert back into <sup>14<\/sup>N. Because the pattern of radioactive decay is so reliable, we can use <sup>14<\/sup>C to accurately date sites up to 55,000 years old (Hajdas et al. 2021). However, <sup>14<\/sup>C can only be used on the remains of biological organisms. This includes charcoal, shell, wood, plant material, and bone. This method involves destroying a small sample of the material. Earlier methods of radiocarbon dating required at least 1 gram of material, but with the introduction of accelerator mass spectrometry (AMS), sample sizes as small as 1 milligram can now be used (Hajdas et al. 2021). This significantly reduces the destructive nature of this method.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The use of radiocarbon dating at Denisova Cave in modern-day Russia revealed an astounding find, the first dated first-generation individual with a Neanderthal mother and Denisovan father. Vivian Slon and colleagues (2018) sequenced the genome, which revealed the individual's hybrid genetic background, and radiocarbon dated the remains, revealing the sub-adult was over 50,000 years old (Slon et al. 2018).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As mentioned before, <sup>14<\/sup>C is unstable and ultimately decays back into <sup>14<\/sup>N. This decay is happening at a constant rate (even now, inside your own body!). However, as long as an organism is alive and taking in food, <sup>14<\/sup>C is being replenished in the body. As soon as an organism dies, it no longer takes in new <sup>14<\/sup>C. We can then use the rate of decay to measure how long it has been since the organism died (Hester et al. 1997, 324). However, the amount of <sup>14<\/sup>C in the atmosphere is not stable over time. It fluctuates based on changes to the earth\u2019s magnetic field and solar activity. In order to turn <sup>14<\/sup>C results into accurate calendar years, they must be calibrated using data from other sources. Annual tree rings (see discussion of <strong>[pb_glossary id=\"904\"]dendrochronology[\/pb_glossary]<\/strong> below), <strong>[pb_glossary id=\"906\"]foraminifera[\/pb_glossary]<\/strong> from stratified marine sediments, and microfossils from lake sediments can be used to chart the changes in <sup>14<\/sup>C as \u201ccalibration curves.\u201d The radiocarbon date obtained from the sample is compared to the established curve and then adjusted to reflect a more accurate calendar date (see Figure 7.24). The curves are updated over time with more data so that we can continue to refine radiocarbon dates (T\u00f6rnqvist et al. 2016). The most recent calibration curves were released in 2020 and may change the dates for some existing sites by hundreds of years (Jones 2020).<\/p>\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"547\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image17-2.jpg\" alt=\"Radiocarbon date calibration curve. \" width=\"547\" height=\"384\" \/> Figure 7.24: This is a simplified example of a calibration curve, showing how the radiocarbon age (y axis) is compared with the calibration curve to produce calibrated dates (x axis). <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 href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Radiocarbon_Date_Calibration_Curve.svg\">Radiocarbon Date Calibration Curve<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:HowardMorland\">HowardMorland<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/\">CC BY-SA 3.0 License<\/a>. [Based on information from Reimer et al. 2004. Radiocarbon 46: 1029-58.][\/caption]\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As you will see in the hominin chapters (Chapters 9\u201312), 55,000 years is only a tiny fragment of human evolutionary history. It is insignificant in the context of the age of our planet. In order to date even older fossils, other methods are necessary.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"908\"]Potassium-argon (K-Ar) dating[\/pb_glossary]<\/strong> and <strong>[pb_glossary id=\"910\"]argon-argon (Ar-Ar) dating[\/pb_glossary]<\/strong> can reach further back into the past than radiocarbon dating. Used to date volcanic rock, these techniques are based on the decay of unstable potassium 40 (<sup>40<\/sup>K) into argon 40 (<sup>40<\/sup>Ar) gas, which gets trapped in the crystalline structures of volcanic material. It is a method of indirect dating. Instead of dating the fossil itself, K-Ar and Ar-Ar dates volcanic layers around the fossil. It will tell you when the volcanic eruption that deposited the layers occurred. This is where stratigraphy becomes important. The date of the surrounding layers can give you a minimum and maximum age of the fossil based on where it is in relation to those layers. This technique was used at Gesher Benot Ya'aqo in the Jordan Valley, dating early stratigraphic deposits of basalt flows to 100,000 years old (Bar-Yosef and Belmaker 2011). The site is unique because early layers of occupation with an Acheulean handaxe industry were made primarily of basalt, which is an uncommon material for this tool technology (see Chapter 10 for a full discussion of this tool technology). The benefit of this dating technique is that <sup>40<\/sup>K has a half-life of circa 1.3 billion years, so it can be used on sites as young as 100 kya and as old as the age of Earth. As you will see in later chapters, it is particularly useful in dating early hominin sites in Africa (Michels 1972, 120; Renfrew and Bahn 2016, 155). Another benefit to this technique is that it does not damage precious fossils because the samples are taken from the surrounding rock instead. However, this method is not without its flaws. A study by J. G. Funkhouser and colleagues (1966) and Raymond Bradley (2015) demonstrated that igneous rocks with fluid inclusions, such as those found in Hawai\u2018i, can release gasses including radiogenic argon when crushed, leading to incorrectly older dates. This is an example of why it is important to use multiple dating methods in research to detect anomalies.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"912\"]Uranium series dating[\/pb_glossary]<\/strong> is based on the decay chain of unstable isotopes of uranium. It uses mass spectrometry to detect the ratios of uranium 238 (<sup>238<\/sup>U), uranium 234(<sup>234<\/sup>U), and thorium 230 (<sup>230<\/sup>Th) in carbonates (Wendt et al. 2021). Thorium accumulates in the carbonate sample through radiometric decay. Thus, the age of the sample is calculated from the difference between a known initial ratio and the ratio present in the sample to be dated. This makes uranium series ideal for dating carbonate rich deposits such as carbonate cements from glacial moraine deposits, speleothems (deposits of secondary minerals that form on the walls, floors, and ceilings of caves, like stalactites and stalagmites), marine and lacustrine carbonates from corals, caliche, and tufa, as well as bones and teeth (University of Arizona, n.d.; van Calsteren and Thomas 2006). Due to the timing of the decay process, this dating technique can be used from a few years up to 650k (Wendt et al. 2021). Since many early hominin sites occur in cave environments, this dating technique can be very powerful. This method has also been used to develop more accurate calibration curves for radiocarbon dating. However, the accuracy of this method depends on knowing the initial ratios of the elements and ruling out possible contamination (Wendt et al. 2021). It also involves the destruction of a small sample of material.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"914\"]Fission track dating[\/pb_glossary] <\/strong>is another useful dating technique for sites that are millions of years old. This is based on the decay of radioactive uranium 238 (<sup>238<\/sup>U). The unstable atom of <sup>238<\/sup>U fissions at a predictable rate. The fission takes a lot of energy and causes damage to the surrounding rock. For instance, in volcanic glasses we can see this damage as trails in the glass. Researchers in the lab take a sample of the glass and count the number of fission trails using an optical microscope. As <sup>238<\/sup>U has a half-life of 4,500 million years, it can be used to date rock and mineral material starting at just a few decades and extending back to the age of Earth. As with K-Ar, archaeologists are not dating artifacts directly. They are dating the layers around the artifacts in which they are interested (Laurenzi et al. 2007).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>[pb_glossary id=\"916\"]Luminescence dating[\/pb_glossary]<\/strong>, which includes thermoluminescence and a related technique called optically stimulated luminescence, is based on the naturally occurring background radiation in soils. Pottery, baked clay, and sediments that include quartz and feldspar are bombarded by radiation from the soils surrounding it. Electrons in the material get displaced from their orbit and trapped in the crystalline structure of the pottery, rock, or sediment. When a sample of the material is heated to 500\u00b0C (thermoluminescence) or exposed to particular light wavelengths (optically stimulated luminescence) in the laboratory, this energy gets released in the form of light and heat and can be measured (Cochrane et al. 2013; Renfrew and Bahn 2016, 160). You can use this method to date artifacts like pottery and burnt flint directly. When attempting to date fossils, you may use this method on the crystalline grains of quartz and feldspar in the surrounding soils (Cochrane et al. 2013). The important thing to remember with this form of dating is that heating the artifact or soils will reset the clock. The method is not necessarily dating when the object was last made or used but when it was last heated to 500\u00b0C or more (pottery) or exposed to sunlight (sediments). Luminescence dating can be used on sites from less than 100 years to over 100,000 years (Duller 2008, 4). As with all archaeological data, context is crucial to understanding the information.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Like thermoluminescence dating, <strong>[pb_glossary id=\"918\"]electron spin resonance dating[\/pb_glossary]<\/strong> is based on the measurement of accumulated background radiation from the burial environment. It is used on artifacts and rocks with crystalline structures, including tooth enamel, shell, and rock\u2014those for which thermoluminescence would not work. The radiation causes electrons to become dislodged from their normal orbit. They become trapped in the crystalline matrix and affect the electromagnetic energy of the object. This energy can be measured and used to estimate the length of time in the burial environment. This technique works well for remains as old as two million years (Carvajal et al. 2011, 115\u2013116). It has the added benefit of being nondestructive, which is an important consideration when dealing with irreplaceable material.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Not all chronometric dating methods are based on unstable isotopes and their rates of decay. There are several other methods that make use of other natural biological and geologic processes. One such method is known as dendrochronology (Figure 7.25), which is based on the natural growth patterns of trees. Trees create concentric rings as they grow; the width of those rings depends on environmental conditions and season. The age of a tree can be determined by counting its rings, which also show records of rainfall, droughts, and forest fires.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><img class=\"alignleft\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image16-1.png\" alt=\"A tree, cross-section of tree core, and tree-ring timeline.\" width=\"413\" height=\"450\" \/><\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"411\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image23-1-1.png\" alt=\"Tree rings and dates.\" width=\"411\" height=\"424\" \/> Figure 7.25: Dendrochronology uses the variations in tree rings to create timelines. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Dendrochronology (Figure 7.34)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">Tree rings can be used to date wood artifacts and ecofacts from archaeological sites. This first requires the creation of a profile of trees in a particular area. The Laboratory of Tree-Ring Research at the University of Arizona has a comprehensive and ongoing catalog of tree profiles (see University of Arizona n.d.). Archaeologists can then compare wood artifacts and ecofacts with existing timelines, provided the tree rings are visible, and find where their artifacts fit in the pattern. Dendrochronology has been in use since the early 20th century (Dean 2009, 25). The Northern Hemisphere chronology stretches back nearly 14,000 years (Reimer et al. 2013, 1870) and has been used successfully to date southwestern U.S. sites such as Pueblo Bonito and Aztec Ruin (Dean 2009, 26). Dendrochronological evidence has helped calibrate radiocarbon dates and even provided direct evidence of global warming (Dean 2009, 26\u201327).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">In Australia, dendrochronology, along with other environmental reconstruction methods, has been used to show that the Indigenous people had sophisticated land management systems before the arrival of British invaders. According to the work of Michael-Shawn Fletcher and colleagues (2021), there was a significant encroachment of the rainforests and tree species into grasslands after the British invasion. Prior to this time, Indigenous people managed the landscape through controlled burns at regular intervals. This practice created climate-resistant grasslands that were biodiverse and provided predictable food supplies for humans and other animals. Under European land management, there have been negative impacts on biodiversity and climate resilience and an increase in catastrophic wildfires (Fletcher et al. 2021).<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">This dating method does have its difficulties. Some issues are interrupted ring growth, microclimates, and species growth variations. This is addressed through using multiple samples, statistical analysis, and calibration with other dating methods. Despite these limitations, dendrochronology can be a powerful tool in dating archaeological sites (Hillam et al. 1990; Kuniholm and Striker 1987).<\/p>\r\n\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Environmental Reconstruction<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As you read in Chapter 2, Charles Darwin, Jean-Baptiste Lamarck, Alfred Russel Wallace, and others recognized the importance of the environment in shaping the evolutionary course of animal species. To understand what selective processes might be shaping evolutionary change, we must be able to reconstruct the environment in which the organism was living.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">One of the ways to do that is to look at the plant species that lived in the same time range as the species in which you are interested. One way to identify ancient flora is to analyze <strong>[pb_glossary id=\"920\"]sediment cores[\/pb_glossary]<\/strong> from water and other protected sources. Pollen gets released into the air and some of that pollen will fall on wetlands, lakes, caves, and so forth. Eventually it sinks to the bottom of the lake and forms part of the sediment. This happens year after year, so subsequent layers of pollen build up in an area, creating strata. By taking a core sample and analyzing the pollen and other organic material, an archaeologist can build a timeline of plant types and see changes in the vegetation of the area (Hester et al. 1997, 284). This can even be done over large areas by studying ocean bed cores, which accumulate pollen and dust from large swaths of neighboring continents.<\/p>\r\n<p class=\"import-Normal\">While sediment coring is one of the more common ways to reconstruct past environments, there are a few other methods. These have been recently employed at Holocene Lake Ivanpah, a paleolake that straddles the California and Nevada border in the United States. This lake was originally thought to have been completely dry around 9,300\u20137,800 kya (Sims and Spaulding 2017). However, analyzing core samples using soil identification, sediment chemistry, subsurface stratigraphy, and <strong>[pb_glossary id=\"922\"]geomorphology[\/pb_glossary]<\/strong> (the study of the physical characteristics of the Earth\u2019s surface) revealed deposition of three recent lake fillings during this period in the forms of additional hardpan, or lake bottom, playas, bedded or layered fine-grained (wetland) sediments, and buried beaches below the surface (Sims and Spaulding 2017; Spaulding and Sims 2018). These discoveries are important because they have not been integrated into interpretation of the local archaeological record, as it was assumed that the lake had been dry for thousands of years. Sedimentological analyses such as coring and those listed above can provide great insight into past climates and are accomplished in a minimally destructive way.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Another way of reconstructing past environments is by using stable isotopes. Unlike unstable isotopes, stable isotopes remain constant in the environment throughout time. Plants take in the isotopes through photosynthesis and ground water absorption. Animals take in isotopes by drinking local water and eating plants. Stable isotopes can be powerful tools for identifying where an organism grew up and what kind of food the organism ate throughout its life. They can even be used to identify global temperature fluctuations.<\/p>\r\n\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Global Temperature Reconstruction<\/em><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Oxygen isotopes are a powerful tool in tracking global temperature fluctuations throughout time. The isotopes of Oxygen 18 (<sup>18<\/sup>O) and Oxygen 16 (<sup>16<\/sup>O) occur naturally in Earth\u2019s water. Both are stable isotopes, but <sup>18<\/sup>O has a heavier atomic weight. In the normal water cycle, evaporation takes water molecules from the surface to the atmosphere. Because <sup>16<\/sup>O is lighter, it is more likely to be part of this evaporation process. The moisture gathers in the atmosphere as clouds that eventually may produce rain or snow and release the water back to the surface of the planet. During cool periods like <strong>[pb_glossary id=\"924\"]glacial periods[\/pb_glossary]<\/strong> (ice ages), the evaporated water often comes down to Earth\u2019s surface as snow. The snow piles up in the winter but, because of the cooler summers, does not melt off. Instead, it gets compacted and layered year after year, eventually resulting in large glaciers or ice sheets covering parts of Earth. Since <sup>16<\/sup>O, with the lighter atomic weight, is more likely to be absorbed in the evaporation process, it gets locked up in glacier formation. The waters left in oceans would have a higher ratio of <sup>18<\/sup>O during these periods of cooler global temperatures (Potts 2012, 154\u2013156; see Figure 7.26).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignleft\" width=\"389\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image15-1.png\" alt=\"Graph with oxygen isotope on y axis and years on x axis.\" width=\"389\" height=\"218\" \/> Figure 7.26: This graph depicts how temperatures of the sea have fluctuated greatly over the course of the history of the planet. <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 href=\"https:\/\/www.giss.nasa.gov\/research\/briefs\/1999_schmidt_01\/\">Oxygen in deep sea sediment carbonate (Figure 2)<\/a> by <a href=\"https:\/\/www.giss.nasa.gov\/\">NASA Goddard Institute for Space Studies<\/a> originally from \"Science Briefs: Cold Climates, Warm Climates: How Can We Tell Past Temperatures?\" by <a href=\"https:\/\/www.giss.nasa.gov\/staff\/gschmidt.html\">Gavin Schmidt<\/a>, is in the <a 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 microorganisms that live in the oceans, foraminifera, absorb the water from their environment and use the oxygen isotopes in their body structures. When these organisms die, they sink to the ocean floor, contributing to the layers of sediment. Scientists can extract these ocean cores and sample the remains of foraminifera for their <sup>18<\/sup>O and <sup>16<\/sup>O ratios. These ratios give us a good approximation of global temperatures deep into the past. Cooler temperatures indicate higher ratios of <sup>18<\/sup>O (Potts 2012, 154\u2013156).<\/p>\r\n\r\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Diet Reconstruction<\/em><\/h4>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">You may be familiar with the saying \u201cyou are what you eat.\u201d When it comes to your teeth and bones, this adage is literal. Stable isotopes can also be used to reconstruct animal diet and migration patterns. Living organisms absorb elements from ingested plants and water. These elements are used in tissues like bones, teeth, skin, hair, and so on. By analyzing the stable isotopes in the bones and teeth of humans and other animals, we can identify the types of food they ate at different stages of their lives.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Plants take in carbon dioxide from the atmosphere during photosynthesis. We\u2019ve already discussed this using the example of the unstable isotope <sup>14<\/sup>C; however, this absorption also takes place with the stable isotopes of <sup>12<\/sup>C and <sup>13<\/sup>C. During photosynthesis, some plants incorporate carbon dioxide as a three-carbon molecule (C3 plants) and some as a four-carbon molecule (C4 plants). On the one hand, C3 plants include certain types of trees and shrubs that are found in relatively wet environments and have lower ratios of <sup>13<\/sup>C compared to <sup>12<\/sup>C. C4 plants, on the other hand, include plants from drier environments like savannahs and grasslands. C4 plants have higher ratios of <sup>13<\/sup>C to <sup>12<\/sup>C than C3 plants (Renfrew and Bahn 2016, 312). These ratios remain stable as you go up the food chain. Therefore, you can analyze the bones and teeth of an animal to identify the <sup>13<\/sup>C\/<sup>12<\/sup>C ratios and identify the types of plants that animal was eating.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The ratios of stable nitrogen isotopes <sup>15<\/sup>N and <sup>14<\/sup>N can also give information about the diet of fossilized or deceased organisms. Though initially absorbed from water and soils by plants, the nitrogen ratios change depending on the primary diet of the organism. An animal who has a mostly vegetarian diet will have lower ratios of <sup>15<\/sup>N to <sup>14<\/sup>N, while those further up the food chain, like carnivores, will have higher ratios of <sup>15<\/sup>N. Interestingly, breastfeeding infants have a higher nitrogen ratio than their mothers, because they are getting all of their nutrients through their mother\u2019s milk. So nitrogen can be used to track life events like weaning (Jay et al. 2008, 2). A marine versus terrestrial diet will also affect the nitrogen signatures. Terrestrial diets have lower ratios of <sup>15<\/sup>N than marine diets. In the course of human evolution, this type of analysis can help us identify important changes in human nutrition. It can help anthropologists figure out when meat became a primary part of the ancient human diet or when marine resources began to be used. The ratios of stable nitrogen isotopes can also be used to determine a change in status, as in the case of the Llullaillaco children (the \u201cice mummies\u201d) found in the Andes Mountains. For instance, the nitrogen values in hair from the Llullaillaco Maiden showed a significant positive shift that is associated with increased meat consumption in the last 12 months of her life (Wilson et al. 2007). Although the two younger children had little changes in their diets in the last year of their short lives, the changes in their nitrogen values were significant enough to suggest that the improvement in their diets may have been attributed to the Incas\u2019 desire to sacrifice healthy, high-status children\u201d (Faux 2012, 6).<\/p>\r\n\r\n<h4 class=\"import-Normal\"><em>Migration<\/em><\/h4>\r\n<p class=\"import-Normal\">Stable isotopes can also tell us a great deal about where an individual lived and whether they migrated during their lifetime. The geology of Earth varies because rocks and soils have different amounts or ratios of certain elements in them. These variations in the ratios of isotopes of certain elements are called isotopic signatures. They are like a chemical fingerprint for a geographical region. These isotopes get into the groundwater and are absorbed by plants and animals living in that area. Elements like strontium, oxygen, and nitrogen, among others, are then used by the body to build bones and teeth. If you ate and drank local water all of your life, your bones and teeth would have the same isotopic signature as the geographical region in which you lived.<\/p>\r\n<p class=\"import-Normal\">However, many people (and animals) move around during their lifetimes. Isotopic signatures can be used to identify migration patterns in organisms (Montgomery et al. 2005). Teeth develop in early childhood. If the isotopes of teeth are analyzed, these isotopes would resemble those found in the geographic area where an individual lived as a child. Bones, however, are a different story. Bones are constantly changing throughout life. Old cells are removed and new cells are deposited to respond to growth, healing, activity change, and general deterioration. Therefore, the isotopic signature of bones will reflect the geographical area in which an individual spent the last seven to ten years of life. If an individual has different isotopic signatures for their bones and teeth, it could indicate a migration some time during their life after childhood.<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"alignright\" width=\"386\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image24-2.jpg\" alt=\"Upright boulders of Stonehenge.\" width=\"386\" height=\"289\" \/> Figure 7.27: Stonehenge continues to provide clues to its mysterious existence with recent research using isotope ratios. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Stonehenge (Figure 7.37)<\/a> by Sarah S. King is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\nRecent work involving stable isotope analysis has been done on the cremation burials from Stonehenge, in Wessex, England (Figure 7.27). Much of the archaeological work at Stonehenge in the past focused on the building and development of the monument itself. That is partly because most of the burials at the monument were cremated remains, which are difficult to study because of their fragmentary nature and the chemical alterations that bone and teeth undergo when heated. The cremation process complicates the oxygen and carbon isotopes. However, the researchers determined that strontium would not be affected by heating and could still be analyzed in cranial fragments. Using the remains of 25 individuals, they compared their strontium signatures to the geology of Wessex and other regions of the UK. Fifteen of those individuals had strontium signatures that matched the local geology. This means that in the last ten or so years of their lives, they lived and ate food from around Stonehenge. However, ten of the individuals did not match the local geologic signature. These individuals had strontium ratios more closely aligned with the geology of west Wales. Archaeologists find this particularly interesting because in the early phases of Stonehenge\u2019s construction, the smaller \u201cblue stones\u201d were brought 200 km from Wales in a feat of early engineering. These larger regional connections show that Stonehenge was not just a site of local importance. It dominated a much larger region of influence and drew people from all over ancient Britain (Snoeck et al. 2018).\r\n<div class=\"textbox\">\r\n<h2 class=\"import-Normal\">Special Topic: Cold Case Naia<\/h2>\r\n[caption id=\"\" align=\"alignleft\" width=\"455\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image4-1-2.png\" alt=\"Sites on Yucatan peninsula.\" width=\"455\" height=\"351\" \/> Figure 7.28: Map of Mexico showing the Yucatan Peninsula and the locations of Hoyo Negro and Sistema Sac Actun. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Hoyo Negro and Sistema Sac Actun, Mexic0 (Figure 7.38)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n<p class=\"import-Normal\">In 2007, cave divers exploring the Sistema Sac Actun in the Yucat\u00e1n Peninsula in Mexico (see Figure 7.28 and 7.29) discovered the bones of a 15- to 16-year-old female human along with the bones of various extinct animals from the Pleistocene (Collins et al. 2015). The site was named Hoyo Negro (\u201cBlack Hole\u201d). The human bones belonged to a Paleo-American, later named \u201cNaia\u201d after a Greek water nymph. Examination of the partially fossilized remains revealed a great deal about Naia\u2019s life, and the radiocarbon dating of her tooth enamel indicated that she lived some 13,000 years ago (Chatters et al. 2014). Naia\u2019s arms were not overly developed, so her daily activities did not involve heavy carrying or grinding of grain or seeds. Her legs, however, were quite muscular, implying that Naia was used to walking long distances. Naia\u2019s teeth and bones indicate habitually poor nutrition. There is evidence of violent injury during the course of Naia\u2019s life from a healed spiral fracture of her left forearm. Naia also suffered from tooth decay and osteoporosis even though she appeared young and undersized. Dr. Jim Chatters hypothesizes that Naia entered the cave at a time when it was not flooded, probably looking for water. She may have become disoriented and fell off a high ledge to her death. The trauma to her pelvis is consistent with such an injury (Watson 2017).<\/p>\r\n<p class=\"import-Normal\">Naia\u2019s skeleton is remarkably complete given its age. As divers were able to locate her skull, Naia\u2019s physical appearance in life could be interpreted. Surprisingly, in examining the skull, it was determined that Naia did not resemble modern Indigenous peoples in the region. However, the<strong> [pb_glossary id=\"926\"]mitochondrial DNA[\/pb_glossary]<\/strong> (mtDNA) recovered from a tooth indicates that Naia shares her DNA with modern Indigenous peoples (Chatters et al. 2014). Though Naia\u2019s burial environment made chemical analysis difficult, researchers were able to recover carbon isotopes from her remains. The isotopes from Naia\u2019s tooth enamel suggest a diet of \u201ccool-season grasses and\/or broad-leaf vegetation\u201d (Chatters et al. 2022, 68). Naia\u2019s teeth also displayed numerous dental caries and only light dental wear. Coupled with the isotopic data, she likely had a \u201csofter, more sugar-rich diet\u201d (Chatters et al. 2022, 68).<\/p>\r\n\r\n\r\n[caption id=\"\" align=\"aligncenter\" width=\"625\"]<img src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image32-1.png\" alt=\"Cross-section of the Hoyo Negro cenote.\" width=\"625\" height=\"353\" \/> Figure 7.29: A diagram of the Sistema Sac Actun and the Hoyo Negro cenote where Naia rested underwater for roughly 13,000 years. The illustration depicts a cenote or hole in the ground leading to a long, narrow tunnel, ending in a large cavern. The cavern and tunnel are both filled with water. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Hoyo Negro cenote (Figure 7.39)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.[\/caption]\r\n\r\n<\/div>\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ff99cc;\">Summary<\/span><\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ff99cc;\">With a timeline that extends back some 4.6 billion years, Earth has witnessed continental drift, environmental changes, and a growing complexity of life. Fossils, the mineralized remains of living organisms, provide physical evidence of life and the environment on the planet over the course of billions of years. In order to better understand the fossil record, anthropologists rely on the collaboration of numerous academic fields and disciplines. Anthropologists use a variety of scientific methods, both relative and chronometric, to analyze fossils to determine age, origins, and migration patterns as well as to provide insight into the health and diet of the fossilized organism. While each method has its advantages, disadvantages, and limited applications, these tools enable anthropologists to theorize how all living organisms evolved, including the evolution of early humans into modern humans, <em>H. sapiens<\/em>. The fossil record is far from complete, but our expanding understanding of the fossil context, with exciting new discoveries and improved scientific methods, enables us to document the history of our planet and the evolution of life on Earth.<\/span><\/p>\r\n\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Dating Methods Quick Guide<\/strong><\/h3>\r\n<div style=\"text-align: left;\">\r\n<table style=\"width: 463.5pt; height: 586px;\">\r\n<thead>\r\n<tr style=\"height: 24.25pt;\">\r\n<td class=\"Table1-C\" style=\"padding: 5pt; border: 1pt solid #000000; height: 30px; width: 157.45px;\">\r\n<p class=\"import-Normal\"><strong>Method<\/strong><\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 1pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\r\n<p class=\"import-Normal\"><strong>Material <\/strong><\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 1pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\r\n<p class=\"import-Normal\"><strong>Effective date range<\/strong><\/p>\r\n<\/td>\r\n<\/tr>\r\n<\/thead>\r\n<tbody>\r\n<tr class=\"Table1-R\" style=\"height: 24.25pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 30px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Stratigraphy<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Soil layers<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Relative<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 36px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Biostratigraphy<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 36px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Plant and animal remains<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 36px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Relative<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 24.25pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 30px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Cultural dating<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Human-made objects<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Relative<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 24.25pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 30px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Fluorine<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Bone, antler, teeth<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Relative<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 78.25pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 90px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Radiocarbon<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 90px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Organic carbon bearing material (bones, teeth, antler, plant material, shell, charcoal)<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 90px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Younger than 55,000 years<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 46px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Potassium-argon and argon-argon<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Volcanic rock<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Older than 100,000 years<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 64.75pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 72px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Uranium series<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 72px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Carbonates such as stalactites, stalagmites, corals, caliche, and tufa<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 72px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Younger than 650,000 years<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 46px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Fission track<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Volcanic glasses and crystalline minerals<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Spans age of Earth<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 46px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Luminescence<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Pottery, baked clay, sediments<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 166.017px;\">\r\n<p class=\"import-Normal\">100 to older than 100,000 years<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 51.25pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 54px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Electron spin resonance dating<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 54px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Tooth enamel, shell, rock with crystalline structures<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 54px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Younger than 2 million years<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr class=\"Table1-R\" style=\"height: 51.25pt;\">\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 61px; width: 157.45px;\">\r\n<p class=\"import-Normal\">Dendrochronology<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 61px; width: 250.533px;\">\r\n<p class=\"import-Normal\">Wood (where tree rings are identifiable)<\/p>\r\n<\/td>\r\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 61px; width: 166.017px;\">\r\n<p class=\"import-Normal\">Dependent on location and available chronologies<\/p>\r\n<\/td>\r\n<\/tr>\r\n<tr style=\"height: 15px;\">\r\n<td style=\"height: 15px; width: 158.317px;\"><\/td>\r\n<td style=\"height: 15px; width: 251.9px;\"><\/td>\r\n<td style=\"height: 15px; width: 166.883px;\"><\/td>\r\n<\/tr>\r\n<\/tbody>\r\n<\/table>\r\n<\/div>\r\n<div class=\"textbox shaded\">\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Review Questions<\/h2>\r\n<ul>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">How do remains become fossils? What conditions are necessary for the fossilization process?<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">What kind of information could you acquire from a single fossil? What could it tell you about the broader environment?<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">What factors would you take into consideration when deciding which dating method to use for a particular artifact?<\/li>\r\n \t<li class=\"import-Normal\" style=\"text-indent: 0pt;\">What methods do anthropologists use to reconstruct past environments and lifestyles?<\/li>\r\n<\/ul>\r\n<\/div>\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Key Terms<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Anaerobic<\/strong>: An oxygen-free environment.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Anthropocene<\/strong>: The proposed name for our current geologic epoch based on human-driven climate change.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Argon-argon (Ar-Ar) dating<\/strong>: A chronometric dating method that measures the ratio of argon gas in volcanic rock to estimate time elapsed since the volcanic rock cooled and solidified. See also <em>potassium-argon dating<\/em>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Atom<\/strong>: A small building block of matter.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Bezoars<\/strong>: Hard, concrete-like substances found in the intestines of fossil creatures.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Biostratigraphy<\/strong>: A relative dating method that uses other plant and animal remains occurring in the stratigraphic context to establish time depth.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Bya<\/strong>: Billion years ago.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Chronometric dating<\/strong>: Dating methods that give estimated numbers of years for artifacts and sites.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Continental drift<\/strong>: The slow movement of continents over time.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Coprolite<\/strong>: Fossilized poop.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Cultural dating<\/strong>: The relative dating method that arranges human-made artifacts in a time frame from oldest to youngest based on material, production technique, style, and other features.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Deep Time<\/strong>: James Hutton\u2019s theory that the world was much older than biblical explanations allowed. This age could be determined by gradual natural processes like soil erosion.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Dendrochronology<\/strong>: A chronometric dating method that uses the annual growth of trees to build a timeline into the past.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Electron spin resonance dating<\/strong>: A chronometric dating method that measures the background radiation accumulated in material over time.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Element<\/strong>: Matter that cannot be broken down into smaller matter.<\/p>\r\n<p class=\"import-Normal\"><strong>Eon<\/strong>: The largest unit of geologic time, spanning billions of years and divided into subunits called <em>eras<\/em>, <em>periods<\/em>, and <em>epochs<\/em>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Epochs<\/strong>: The smallest units of geologic time, spanning thousands to millions of years.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Eras<\/strong>: Units of geologic time that span millions to billions of years and that are subdivided into <em>periods<\/em> and <em>epochs<\/em>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Fission track dating<\/strong>: A chronometric dating method that is based on the fission of <sup>283<\/sup>U.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Fluorine dating<\/strong>: A relative dating method that analyzes the absorption of fluorine in bones from the surrounding soils.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Foraminifera<\/strong>: Single-celled marine organisms with shells.<\/p>\r\n<p class=\"import-Normal\"><strong>Fossilization<\/strong>: The process by which an organism becomes a fossil.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Fossils<\/strong>: Mineralized copies of organisms or activity imprints.<\/p>\r\n<p class=\"import-Normal\"><strong>G<\/strong><strong>eomorphology<\/strong>: The study of the physical characteristics of the Earth\u2019s surface.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Glacial periods<\/strong>: Periods characterized by low global temperatures and the expansion of ice sheets on Earth\u2019s surface.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Holocene<\/strong>: The geologic epoch from 10 kya to present. (See the discussion on \u201cthe Anthropocene\u201d for the debate regarding the current epoch name.)<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Hominin<\/strong>: The term used for humans and their ancestors after the split with chimpanzees and bonobos.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>In matrix<\/strong>: When a fossil is embedded in a substance, such as igneous rock.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Isotopes<\/strong>: Variants of elements.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Kya<\/strong>: Thousand years ago.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Law of Superposition<\/strong>: The scientific law that states that rock and soil are deposited in layers, with the youngest layers on top and the oldest layers on the bottom.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Lithification<\/strong>: The process by which the pressure of sediments squeeze extra water out of decaying remains and replace the voids that appear with minerals from the surrounding soil and groundwater.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Luminescence dating<\/strong>: The chronometric dating method based on the buildup of background radiation in pottery, clay, and soils.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Megafauna<\/strong>: Large animals such as mammoths and mastodons.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Mitochondrial DNA<\/strong>: DNA located in the mitochondria of a cell that is only passed down from biological mother to child.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Mya<\/strong>: Million years ago.<\/p>\r\n<p class=\"import-Normal\"><strong>P<\/strong><strong>aleopathology<\/strong>: Study of ancient diseases and injuries identified through examining remains.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Periods<\/strong>: Geologic time units that span millions of years and are subdivided into <em>epochs<\/em>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Permineralization<\/strong>: When minerals from water impregnate or replace organic remains, leaving a fossilized copy of the organism.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Petrified wood<\/strong>: A fossilized piece of wood in which the original organism is completely replaced by minerals through petrifaction.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Potassium-argon (K-Ar) dating<\/strong>: A chronometric dating method that measures the ratio of argon gas in volcanic rock to estimate time elapsed since the volcanic rock cooled and solidified. See also <em>argon-argon dating<\/em>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Pseudofossils<\/strong>: Natural rocks or mineral formations that can be mistaken for fossils.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Radioactive decay<\/strong>: The process of transforming the atom by spontaneously releasing energy.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Radiocarbon dating<\/strong>: The chronometric dating method based on the radioactive decay of <sup>14<\/sup>C in organic remains.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Relative dating<\/strong>: Dating methods that do not result in numbers of years but, rather, in relative timelines wherein some organisms or artifacts are older or younger than others.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Sediment cores<\/strong>: Core samples taken from lake beds or other water sources for analysis of their pollen.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Stable isotopes<\/strong>: Variants of elements that do not change over time without outside interference.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Stratigraphy<\/strong>: A relative dating method that is based on ordered layers or (strata) that build up over time.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Taphonomy<\/strong>: The study of what happens to an organism after death.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Trace fossils<\/strong>: Fossilized remains of activity such as footprints.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Uniformitarianism<\/strong>: The theoretical perspective that the geologic processes observed today are the same as the processes operating in the past.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Unstable isotopes<\/strong>: Variants of elements that spontaneously change into stable isotopes over time.<\/p>\r\n<p class=\"import-Normal\"><strong>Uranium series dating<\/strong>: A radiometric dating method based on the decay chain of unstable isotopes of <sup>238<\/sup>U and <sup>235<\/sup>U.<\/p>\r\n\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">About the Authors<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><img class=\"alignleft\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image9-1.jpg\" alt=\"A woman with curly blonde hair and sunglasses smiles in front of a mountain landscape.\" width=\"179\" height=\"250\" \/><\/p>\r\n\r\n<h3 class=\"import-Normal\">Sarah S. King, Ph.D.<\/h3>\r\n<p class=\"import-Normal\">Cerro Coso Community College, sarah.king1@cerrocoso.edu<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dr. Sarah S. King is an anthropology\/sociology professor at Cerro Coso Community College in California. She completed her Ph.D. work at the Division of Archaeological, Geographical and Environmental Sciences at the University of Bradford in West Yorkshire, England. Her thesis was entitled \u201cWhat Makes War?: Assessing Iron Age Warfare through Mortuary Behavior and Osteological Patterns of Violence.\u201d She also holds anthropology degrees from the University of California, Santa Cruz (B.A. hons., 2004), and the University of New Mexico, Albuquerque (M.A., 2006).<\/p>\r\n&nbsp;\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><img class=\"alignleft wp-image-253\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390.jpg\" alt=\"A person with short, curly brown hair and glasses smiles at the camera.\" width=\"180\" height=\"254\" \/>Kara Jones, M.A.<\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">PhD student at University of Nevada, Las Vegas, jonesk44@unlv.nevada.edu<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Kara Jones received their B.A. in anthropology at California State University, Bakersfield (2018) and their M.A. from University of Nevada, Las Vegas (2023, summer). Their master\u2019s thesis is titled \u201cRockin\u2019 at the Lake: Toolstone Use and Procurement along Holocene Lake Ivanpah, CA.\u201d Mx Jones is a Mojave Desert archaeologist specializing in stone tool use and manufacture, focusing further on Holocene lakeshore adaptations.<\/p>\r\n\r\n<\/div>\r\n<h2>For Further Exploration<\/h2>\r\n<div class=\"__UNKNOWN__\">\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Books<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Bjornerud, Marcia. 2006. <em>Reading the Rocks: The Autobiography of the Earth<\/em>. New York: Basic Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hazen, Robert M. 2013. <em>The Story of Earth: The First 4.5 Billion Years, From Stardust to Living Planet<\/em>. New York: Viking Penguin.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Holmes, Richard. 2010. <em>The Age of Wonder: The Romantic Generation and the Discovery of the Beauty and Terror of Science<\/em>. New York: Vintage.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Palmer, Douglas. 2005. <em>Earth Time: Exploring the Deep Past from Victorian England to the Grand Canyon<\/em>. New York: John Wiley &amp; Sons.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Prothero, Donald R. 2015. <em>The Story of Life in 25 Fossils: Tales of Intrepid Fossil Hunters and the Wonder of Evolution<\/em>. New York: Columbia University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Pyne, Lydia. 2016. <em>Seven Skeletons: The Evolution of the World\u2019s Most Famous Human Fossils<\/em>. New York: Viking Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Repcheck, Jack. 2009. <em>The Man Who Found Time: James Hutton and the Discovery of the Earth\u2019s Antiquity<\/em>. New York: Basic Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taylor, Paul D., Aaron O\u2019Dea. 2014. <em>A History of Life in 100 Fossils<\/em>. Washington, DC: Smithsonian Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ward, David. 2002. <em>Smithsonian Handbooks: Fossils<\/em>. Washington, DC: Smithsonian Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Winchester, Simon. 2009. <em>The Map That Changed the World: William Smith and the Birth of Modern Geology<\/em>. New York: Harper Perennial.<\/p>\r\n\r\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Websites<\/strong><\/h3>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.ambermuseum.eu\/en\/\">Amber Museum<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.etsu.edu\/cas\/paleontology\/\">East Tennessee State University Center of Excellence in Paleontology<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.granger.com\/\">Granger Historical Picture Archive<\/a><\/p>\r\n<p class=\"import-Normal\"><a href=\"https:\/\/www.facebook.com\/indigarchs\/\">Indigenous Archaeology Collective<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/tarpits.org\">La Brea Tar Pits Museum<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.lymeregismuseum.co.uk\">Lyme Regis Museum<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.nhm.ac.uk\/discover\/mary-anning-unsung-hero.html\">Natural History Museum (London), on Mary Anning<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/en.pechmerle.com\">Pech Merle Cave<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.nps.gov\/pefo\/index.htm\">Petrified Forest National Park (NE Arizona)<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/poozeum.com\">Poozeum: The No. 2 Wonder of the World<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/paleobiology.si.edu\/fossiLab\/projects.html\">Smithsonian National Museum of Natural History, Department of Paleobiology<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Smithsonian National Museum of Natural History, on <a href=\"https:\/\/humanorigins.si.edu\">\u201cWhat Does It Mean to be Human\u201d<\/a><\/p>\r\n<p class=\"import-Normal\">Society for American Archaeology, on <a href=\"https:\/\/www.saa.org\/career-practice\/ethics-in-professional-archaeology\">\u201cEthics in Professional Archaeology\u201d<\/a><\/p>\r\n<p class=\"import-Normal\">Society for American Archaeology, <a href=\"https:\/\/archaeologicalethics.org\/code-of-ethics\/society-for-american-archaeology-principles-of-archaeological-ethics\/\">\u201cPrinciples of Archaeological Ethics\u201d<\/a><\/p>\r\n\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">References<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Antoine, Pierre-Oliver, Maeva J. Orliac, Gokhan Atici, Inan Ulusoy, Erdal Sen, H. Evren \u00c7ubuk\u00e7u, Ebru lbayrak, Ne\u015fe Oyal, Erkan Aydar, and Sevket Sen. 2012. \u201cA Rhinocerotid Skull Cooked to Death in a 9.2 Mya-Old Ignimbrite Flow of Turkey.\u201d <em>PLoS ONE<\/em> 7 (11): e49997.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Aufderheide, Arthur C. 2003. <em>The Scientific Study of Mummies<\/em>. Cambridge, UK: Cambridge University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Bar-Yosef, O., and M. Belmaker. 2011. \u201cEarly and Middle Pleistocene Faunal and Hominins Dispersals through Southwestern Asia.\u201d<em> Quaternary Science Reviews<\/em> 30 (11\u201312): 1318\u20131337.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Barras, C. 2022. \u201cLost Footprints of Our Ancestors.\u201d <em>New Scientist<\/em> 254 (3381): 40\u201344.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Blong, John C., Martin E. Adams, Gabriel Sanchez, Dennis L. Jenkins, Ian D. Bull, and Lisa-Marie Shillito. 2020. \u201cYounger Dryas and Early Holocene Subsistence in the Northern Great Basin: Multiproxy Analysis of Coprolites from the Paisley Caves, Oregon, USA.\u201d <em>Archaeological and Anthropological Sciences<\/em> 12 (9): 1\u201329.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Boaz, Noel T., Russel L. Ciochon, Qinqi Xu, and Jinyi Liu. 2004. \u201cMapping and Taphonomic Analysis of the <em>Homo erectus<\/em> Loci at Locality 1 Zhoukoudian, China.\u201d <em>Journal of Human Evolution <\/em>46 (5): 519\u2013549.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Booth, Thomas J., Andrew T. Chamberlain, and Mike Parker Pearson. 2015. \u201cMummification in Bronze Age Britain.\u201d <em>Antiquity<\/em> 89 (347): 1,155\u20131,173.<\/p>\r\n<p class=\"import-Normal\">Bradley, Raymond S. 2015. \u201cChapter 3: Dating Methods I.\u201d In <em>Paleoclimatology<\/em>, edited by Raymond S. Bradley, 55\u2013101. Cambridge, MA: Academic Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Brown, Theodore L., H. Eugene LeMay Jr., Bruce E. Burston, Catherine J. Murphy, Patrick M. Woodward, and Matthew Stoltzfus. 2018. <em>Chemistry: The Central Science.<\/em> New York: Pearson.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Campbell, Neil A., and Jane B. Reece. 2005. <em>Biology 7th ed. <\/em>New York: Pearson.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Carvajal, Eduar, Luis Montes, and Ovidio A. Almanza. 2011. \u201cQuaternary Dating by Electron Spin Resonance (ESR) Applied to Human Tooth Enamel.\u201d <em>Earth Sciences Research Journal<\/em> 15 (2): 115\u2013120.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Chatters, James C., Joaquin Arroyo-Cabrales, and Pilar Luna-Erreguerena. 2022. \u201cThe Pre-Ceramic Skeletal Record of Mexico and Central America.\u201d In <em>The Routledge Handbook of Mesoamerican Bioarchaeology,<\/em> edited by V. Tieslar, 49\u201374. New York: Routledge.<\/p>\r\n<p class=\"import-Normal\">Chatters, James C., Douglas J. Kennett, Yemane Asmerom, Brian M. Kemp, Victor Polyak, Alberto Nava Blank, Patricia A. Beddows, et al. 2014. \u201cLate Pleistocene Human Skeleton and mtDNA Link Paleoamericans and Modern Native Americans.\u201d <em>Science<\/em> 344 (6185): 750\u2013754.<\/p>\r\n<p class=\"import-Normal\">Clough, Sharon. 2020. \"Ethics in Human Osteology.\" <em>The Archaeologist<\/em> 109 (2020): 3\u20135.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cochrane, Grant W. G., Trudy Doelman, and Lyn Wadley. 2013. \u201cAnother Dating Revolution for Prehistoric Archaeology?\u201d <em>Journal of Archaeological Method and Theory<\/em> 20 (1): 42\u201360.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Collins, S. V., E. G. Reinhardt, D. Rissolo, J. C. Chatters, A. Nava-Blank, and P. Luna-Erreguerena. 2015. \u201cReconstructing Water Level in Hoyo Negro, Quintana Roo, Mexico: Implications for Early Paleoamerican and Faunal Access.\u201d <em>Quaternary Science Reviews <\/em>124: 68\u201383.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cook, Harold J. 1928. \u201cGlacial Age Man in New Mexico.\u201d <em>Scientific American<\/em> 139 (1): 38\u201340.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cook, S. F., and H. C. Ezra-Cohn. 1959. \u201cAn Evaluation of the Fluorine Dating Method.\u201d <em>Southwestern Journal of Anthropology <\/em>15 (3): 276\u2013290.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cooper, Arnie. 2010. \u201cSticky Situation at the Tar Pits.\u201d <em>LA Weekly<\/em>, May 27, 2010. https:\/\/www.laweekly.com\/sticky-situation-at-the-tar-pits\/.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Crompton, Robin H., Todd C. Pataky, Russell Savage, Kristiaan D\u2019Ao\u00fbt, Matthew R. Bennett, Michael H. Day, Karl Bates, Sarita Morse, and William I. Sellers. 2012. \u201cHuman-like External Function of the Foot, and Fully Upright Gait, Confirmed in the 3.66 Million Year Old Laetoli Hominin Footprints by Topographic Statistics, Experimental Footprint-Formation and Computer Simulation.\u201d <em>Journal of the Royal Society Interface<\/em> 9 (69): 707\u2013719. doi: 10.1098\/rsif.2011.0258<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Crutzen, Paul J., and Eugene F. Stoermer. 2000. \u201cThe \u2018Anthropocene.\u2019\u201d <em>Global Change Newsletter<\/em> 41: 17\u201318.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Darwin, Charles. 1859. <em>On the Origin of Species<\/em>. London, UK: John Murray.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dean, Jeffery S. 2009. \u201cOne Hundred Years of Dendroarchaeology: Dating, Human Behavior, and Past Climate.\u201d In <em>Tree-rings, Kings, and Old World Archaeology and Environment: Papers Presented in Honor of Peter Ian Kuniholm<\/em>, edited by S. Manning and M. J. Bruce, 25\u201332. Oxford, UK: Oxbow Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dolnick, Edward. 2011. <em>The Clockwork Universe: Isaac Newton, the Royal Society, and the Birth of the Modern World<\/em>. New York: HarperCollins.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Duller, G.A.T. 2008. <em>Luminescence Dating: Guidelines on Using Luminescence Dating in Archaeology<\/em>. Swindon, UK: English Heritage.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Eisenbeiss, Sabine. 2016. \u201cPreserved in Peat: Decoding Bodies from Lower Saxony, Germany.\u201d <em>Expedition<\/em> 58 (2): 18\u201321.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Emling, Shelley. 2009. <em>The Fossil Hunter: Dinosaurs, Evolution, and the Woman Whose Discoveries Changed the World<\/em>. New York: St. Martin\u2019s Griffin.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Faux, Jennifer L. 2012. \u201cHail the Conquering Gods: Ritual Sacrifice of Children in Inca Society.\u201d <em>Journal of Contemporary Anthropology<\/em> 3 (1): 1\u201315.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Feder, Kenneth L. 2017. <em>The Past in Perspective: An Introduction to Human Prehistory<\/em>. 7th ed. New York: Oxford University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fletcher, Michael-Shawn, Tegan Hall, and Andreas Nicholas Alexandra. 2021. \u201cThe Loss of an Indigenous Constructed Landscape Following British Invasion of Australia: An Insight into the Deep Human Imprint on the Australian Landscape.\u201d <em>Ambio<\/em> 50 (1): 138\u2013149.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Flowers, Paul, Klaus Theopold, Richard Langley, and William R. Robinson. 2018. <em>Chemistry<\/em>. Houston, TX: Openstax, Rice University.<\/p>\r\n<p class=\"import-Normal\">Fumagalli, Matteo, Ida Moltke, Niels Grarup, Fernando Racimo, Peter Bjerregaard, Marit E. J\u00f8rgensen, Thorfinn S. Korneliussen, Pascale Gerbault, Line Skotte, Allan Linneberg, Cramer Christensen, Ivan Brandslund, Torben J\u00f8rgensen, Emilia Huerta-S\u00e1nchez, Erik B. Schmidt, Oluf Pedersen, Torben Hansen, Anders Albrechtsen, and Rasmus Nielsen. 2015. \u201cGreenlandic Inuit show genetic signatures of diet and climate adaptation.\u201d <em>Science<\/em> 349 (6254): 1343-1347.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Funkhouser, J. G., I. L. Barnes, and J. J. Naughton. 1966. \u201dProblems in the Dating of Volcanic Rocks by the Potassium-Argon Method.\u201d<em> Bull Volcanol<\/em> 29: 709\u2013717.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Giles, Melanie. 2020. <em>Bog Bodies: Face to Face with the Past.<\/em> Manchester, UK: Manchester University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Goodrum, Matthew R., and Cora Olson. 2009. \u201cThe Quest for an Absolute Chronology in Human Prehistory: Anthropologists, Chemists, and the Fluorine Dating Method in Palaeoanthropology.\u201d <em>British Journal for the History of Science<\/em> 42 (1): 95\u2013114.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Granger, Darryl E., Ryan J. Gibbon, Kathleen Kuman, Ronald J. Clarke, Laurent Bruxelles, and Marc W. Caffee. 2015. \u201cNew Cosmogenic Burial Ages for Sterkfontein Member 2 <em>Australopithecus<\/em> and Member 5 Oldowan.\u201d <em>Nature<\/em> 522 (7554): 85\u201388.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Granger Historical Picture Archive. 2018. <em>Cro-Magnon Footprint<\/em>. Image no. 0167868. Accessed March, 02, 2023. <a class=\"rId129\" href=\"https:\/\/www.granger.com\/results.asp?image=0167868&amp;itemw=4&amp;itemf=0001&amp;itemstep=1&amp;itemx=11&amp;screenwidth=1085\">https:\/\/www.granger.com\/results.asp?image=0167868&amp;itemw=4&amp;itemf=0001&amp;itemstep=1&amp;itemx=11&amp;screenwidth=1085<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Gruhn, R., 2020. \u201cEvidence Grows That Peopling of the Americas Began More Than 20,000 Years Ago.\u201d <em>Nature<\/em> 584: 47\u201348.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Haddy, A., and A. Hanson. 1982. \u201cResearch Notes and Application Reports Nitrogen and Fluorine Dating of Moundville Skeletal Samples. <em>Archaeometry<\/em> 24 (1): 37\u201344.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hajdas, I., P. Ascough, M. H. Garnett, S. J. Fallon, C. L. Pearson, G. Quarta, K. L. Spalding, H. Yamaguchi, and M. Yoneda. 2021. \u201cRadiocarbon Dating.\u201d <em>Nature Reviews Methods Primers<\/em> 1 (62): 1\u201326.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hatala, Kevin G., Brigitte Demes, and Brian G. Richmond. 2016. \u201cLaetoli Footprints Reveal Bipedal Gait Biomechanics Different from Those of Modern Humans and Chimpanzees.\u201d <em>Proceedings of the Royal Society B<\/em> 283: 20160235. <a class=\"rId130\" href=\"https:\/\/dx.doi.org\/10.1098\/rspb.2016.0235\">https:\/\/dx.doi.org\/10.1098\/rspb.2016.0235<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hester, Thomas R., Harry J. Shafer, and Kenneth L. Feder. 1997. <em>Field Methods in Archaeology<\/em>, 7th ed. Mountain View, CA: Mayfield Publishing.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hillam, J., C. M. Groves, D. M. Brown, M. G. L. Baillie, J. M. Coles, and B. J. Coles. 1990. \u201cDendrochronology of the English Neolithic.\u201d <em>Antiquity<\/em> 64 (243): 210\u2013220.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Holmes, Richard. 2010. <em>The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science<\/em>. New York: Vintage.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ingber, Sasha. 2012. \u201cVolcano Eruption Baked Rare Rhino Fossil.\u201d <em>National Geographic News<\/em>, November 30, 2012. Accessed July 25, 2018. https:\/\/www.nationalgeographic.com\/science\/article\/121130-rare-rhino-fossil-created-by-volcanic-explosion.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Jay, Mandy, B. T. Fuller, Michael P. Richards, Christopher J. Kn\u00fcsel, and Sarah S. King. 2008. \u201cIron Age Breastfeeding Practices in Britain: Isotopic Evidence from Wetwang Slack, East Yorkshire.\u201d <em>American Journal of Physical Anthropology<\/em> 136 (3): 327\u2013337.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Jones, Nicola. 2020. \u201cCarbon Dating, the Archaeological Workhorse, Is Getting a Major Reboot.\u201d <em>Nature<\/em><em> News<\/em>, May 19, 2020. doi: <a class=\"rId131\" href=\"https:\/\/doi.org\/10.1038\/d41586-020-01499-y\">https:\/\/doi.org\/10.1038\/d41586-020-01499-y<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Klein, Richard G. 1999. <em>The Human Career: Human Biological and Cultural Origins<\/em>, 2nd ed. Chicago: University of Chicago Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Komar, Debra A., and Jane E. Buikstra. 2008. <em>Forensic Anthropology: Contemporary Theory and Practice<\/em>. New York: Oxford University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Kuniholm, Peter Ian, and Cecil L. Striker. 1987. \u201cDendrochronological Investigations in the Aegean and Neighboring Regions, 1983\u20131986.\u201d <em>Journal of Field Archaeology<\/em> 14 (4): 385\u2013398.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Laurenzi, Marinella A., Maria Laura Balestrieri, Giulio Bigazzi, Julio C. Hadler Neto, Pedro J. Iunes, Pio Norelli, Massimo Oddone, Ana Maria Osorio Araya, and Jos\u00e9 G. Viramonte. 2007. \u201cNew Constraints on Ages of Glasses Proposed as Reference Materials for Fission-Track Dating.\u201d <em>Geostandards &amp; Geoanalytical Research<\/em> 31 (2): 105\u2013124.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Lebatard, Anne-Elisabeth, Didier L. Bourl\u00e8s, Philippe Duringer, Marc Jolivet, R\u00e9gis Braucher, Julien Carcaillet, Mathieu Schuster, et al. 2008. \u201cCosmogenic Nuclide Dating of <em>Sahelanthropus tchadensis<\/em> and <em>Australopithecus bahrelghazali<\/em>: Mio-Pliocene Hominids from Chad.\u201d <em>Proceedings of the National Academy of Sciences<\/em> 105 (9): 3226\u20133231.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Lyell, Charles. 1830\u20131833. <em>Principles of Geology, Being an Attempt to Explain the Former Changes of the Earth\u2019s Surface, by Reference to Causes Now in Operation<\/em>. 3 vols. London: John Murray.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Maixner, Frank, Dmitrij Turaev, Amaury Cazenave-Gassiot, Marek Janko, Ben Krause-Kyora, Michael R. Hoopmann, Ulrike Kusebauch, et al. 2018. \u201cThe Iceman\u2019s Last Meal Consisted of Fat, Wild Meat, and Cereals.\u201d <em>Current Biology<\/em> Report 28 (14): 2348\u20132355.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Masao, Fidelis T., Elgidius B. Ichumbaki, Marco Cherin, Angelo Barili, Giovanni Boschian, David A. Lurino, Sofia Menconero, Jacopo Moggi-Cecchi, and Giorgio Manzi. 2016. \u201cNew Footprints from Laetoli (Tanzania) Provide Evidence for Marked Body Size Variation in Early Hominins.\u201d\u00a0<em>eLife <\/em>5: e19568. <a class=\"rId132\" href=\"https:\/\/elifesciences.org\/articles\/19568\">https:\/\/elifesciences.org\/articles\/19568<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">McDonough, Katelyn, Taryn Johnson, Ted Goebel, and Karl Reinhard. 2022. \u201cDisease, Diet, and Thorny Headed Worm Infection in the Great Basin.\u201d Paper presented at 50th Annual Meeting of the Nevada Archaeological Association, Tonopah, Nevada, April 22nd, 2022.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Michels, Joseph W. 1972. \u201cDating Methods.\u201d <em>Annual Review of Anthropolog<\/em>y 1: 113\u2013126.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Monastersky, Richard. 2015. \u201cAnthropocene: The Human Age.\u201d <em>Nature<\/em> 519 (7542): 144\u2013147.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Montgomery, Janet, Jane A. Evans, Dominic Powlesland, and Charlotte A. Roberts. 2005. \u201cContinuity or Colonization in Anglo-Saxon England? Isotope Evidence for Mobility, Subsistence Practice, and Status at West Heslerton.\u201d <em>American Journal of Physical Anthropology<\/em> 126 (2): 123\u2013138.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">National Park Service. 2022. \u201cFossilized Footprints.\u201d <em>National Park Service <\/em>website, February 1. Accessed May 31, 2022. https:\/\/www.nps.gov\/whsa\/learn\/nature\/fossilized-footprints.htm.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Pastoors, Andreas, Tilman Lenssen-Erz, Bernd Breuckmann, Tsamkxao Ciqae, Ui Kxunta, Dirk Rieke-Zapp, and Thui Thao. 2017. \u201cExperience Based Reading of Pleistocene Human Footprints in Pech-Merle.\u201d <em>Quaternary International <\/em>430 (A): 155\u2013162.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Potts, Richard. 2012. \u201cEvolution and Environmental Change in Early Human Prehistory.\u201d <em>Annual Review of Anthropology<\/em> 41: 151\u2013167.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Raichlen, David A., and Adam D. Gordon. 2017. \u201cInterpretation of Footprints From Site S Confirms Human-like Bipedal Biomechanics in Laetoli Hominins.\u201d <em>Journal of Human Evolution<\/em> 107: 134\u2013138.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ravn, Morten. 2010. \u201cBronze and Early Iron Age Bog Bodies from Denmark.\u201d <em>Acta Archaeologica<\/em> 81 (1): 112\u2013113.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Reimer, Paula J., Edouard Bard, Alex Bayliss, J. Warren Beck, Paul G. Blackwell, Christopher Bronk Ramsey, Caitlin E. Buck, et al. 2013. \u201cINTCAL13 and Marine13 Radiocarbon Age Calibration Curves 0\u201350,000 Years cal BP.\u201d <em>Radiocarbon<\/em> 55 (4): 1869\u20131887.<\/p>\r\n<p class=\"import-Normal\">Reinhard, Johan. 2006. <em>Ice Maiden: Inca Mummies, Mountain Gods, and Sacred Sites in the Andes<\/em>. Washington, DC.: National Geographic.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Reitz, Elizabeth J., and Elizabeth S. Wing. 1999. <em>Zooarchaeology<\/em>. Cambridge, UK: Cambridge University Press.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Renfrew, Colin, and Paul Bahn. 2016. <em>Archaeology: Theories, Methods, and Practice<\/em>, 7th ed. New York: Thames and Hudson.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ruddiman, William F., Zhengtang Guo, Xin Zhou, Hanbin Wu, and Yanyan Yu. 2008. \u201cEarly Rice Farming and Anomalous Methane Trends.\u201d <em>Quaternary Science Reviews<\/em> 27 (13\u201314): 1291\u20131295.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Schmidt, Gavin. 1999. \u201cScience Briefs: Cold Climates, Warm Climates: How Can We Tell Past Temperatures?\u201d <em>National Aeronautics and Space Administration Goddard Institute for Space Studies<\/em>. <a class=\"rId133\" href=\"https:\/\/www.giss.nasa.gov\/research\/briefs\/1999_schmidt_01\/\">https:\/\/www.giss.nasa.gov\/research\/briefs\/1999_schmidt_01\/<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Shillito, Lisa-Marie, John C. Blong, Eleanor J. Green, and Eline N. van Asperen. 2020a. \u201cThe What, How and Why of Archaeological Coprolite Analysis.\u201d <em>Earth-Science Reviews<\/em> 207. <a class=\"rId134\" href=\"https:\/\/doi.org\/10.1016\/j.earscirev.2020.103196\">https:\/\/doi.org\/10.1016\/j.earscirev.2020.103196<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Shillito, Lisa-Marie, Helen L. Whelton, John C. Blong, Dennis L. Jenkins, Thomas J. Connolly, and Ian D. Bull. 2020b. \u201cPre-Clovis occupation of the Americas Identified by Human Fecal Biomarkers in Coprolites from Paisley Caves, Oregon.\u201d <em>Science Advances<\/em> 6 (29).\u200b\u200b https:\/\/www.science.org\/doi\/10.1126\/sciadv.aba6404.<\/p>\r\n<p class=\"import-Normal\">Sims, Douglas., and W. Spaulding. 2017. \u201cShallow Subsurface Evidence for Postglacial Holocene Lakes at Ivanpah Dry Lake: An Alternative Energy Development Site in the Central Mojave Desert, California, USA.\u201d <em>Journal of Geography and Geology<\/em> 9 (1): 1\u201324. DOI: <a class=\"rId135\" href=\"https:\/\/doi.org\/10.5539\/jgg.v9n1p1\">10.5539\/jgg.v9n1p1<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Slon, Viviane, Fabrizio Mafessoni, Benjamin Vernot, Cesare De Filippo, Steffi Grote, Bence Viola, Mateja Hajdinjak, St\u00e9phane Peyr\u00e9gne, Sarah Nagel, Samantha Brown, et al. 2018. \u201cThe Genome of the Offspring of a Neanderthal Mother and a Denisovan Father.\u201d <em>Nature<\/em> 561 (7721): 113\u2013116.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Smithsonian National Museum of Natural History. 2018. Laetoli Footprint Trails. Smithsonian National Museum of History, October 23. Accessed February 14, 2023. <a class=\"rId136\" href=\"https:\/\/humanorigins.si.edu\/evidence\/behavior\/footprints\/laetoli-footprint-trails\">https:\/\/humanorigins.si.edu\/evidence\/behavior\/footprints\/laetoli-footprint-trails<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Snoeck, Christophe, John Pouncett, Philippe Claeys, Steven Goderis, Nadine Mattielli, Mike Parker Pearson, Christie Willis, Antoine Zazzo, Julia A. Lee-Thorp, and Rick J. Schulting. 2018. \u201cStrontium Isotope Analysis on Cremated Human Remains from Stonehenge Support[sic] Links With West Wales.\u201d <em>Scientific Reports <\/em>8. <a class=\"rId137\" href=\"https:\/\/www.nature.com\/articles\/s41598-018-28969-8\">https:\/\/www.nature.com\/articles\/s41598-018-28969-8<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Spaulding, W. G., and D. B. Sims. 2018. \u201cA Glance to the East: Lake Ivanpah\u2014An Isolated Southern Great Basin Paleolake. <em>The 2018 Desert Symposium Field Guide and Proceedings<\/em>, 121-131. <a class=\"rId138\" href=\"https:\/\/www.researchgate.net\/publication\/340493333_A_glance_to_the_east_Lake_Ivanpah-_an_isolated_southern_Great_Basin_paleolake\">https:\/\/www.researchgate.net\/publication\/340493333_A_glance_to_the_east_Lake_Ivanpah-_an_isolated_southern_Great_Basin_paleolake<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Spray, Aaron. \u201cLa Brea Woman: Only (&amp; Controversial) Human from La Brea Tar Pits.\u201d <em>The Travel<\/em>, April 3, 2022. Accessed July 31, 2022. <a class=\"rId139\" href=\"https:\/\/www.thetravel.com\/what-to-know-of-the-la-brea-woman\/\">https:\/\/www.thetravel.com\/what-to-know-of-the-la-brea-woman\/<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Steffen, Will, Johan Rockstr\u00f6m, Katherine Richardson, Timothy M. Lenton, Carl Folke, Diana Liverman, Colin P. Summerhayes, et al. 2018. \u201cTrajectories of the Earth System in the Anthropocene.\u201d <em>PNAS <\/em>115 (33): 8252\u20138259.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Stodder, Ann L. W. 2008. \u201cTaphonomy and the Nature of Archaeological Assemblages.\u201d In <em>Biological Anthropology of the Human Skeleton<\/em>, edited by M. Anne Katzenberg and Shelley R. Saunders, 71\u2013115. Hoboken, NJ: Wiley Blackwell.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Straus, Lawrence Guy. 1989. \u201cGrave Reservations: More on Paleolithic Burial Evidence.\u201d <em>Current Anthropology<\/em> 30 (5): 633\u2013634.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Sullivan, Terry, and Harry Gifford. 1908. <em>She Sells Sea-Shells<\/em>. London: Francis, Day, and Hunter.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taylor, Anthony, Jarod M. Hutson, Vaughn M. Bryant, and Dennis L. Jenkins. 2020. \u201cDietary Items in Early to Late Holocene Human Coprolites from Paisley Caves, Oregon, USA.\u201d <em>Palynology<\/em> 44 (1): 12\u201323.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taylor, Paul D., Aaron O\u2019Dea. 2014. <em>A History of Life in 100 Fossils<\/em>. Washington, D.C.: Smithsonian Books.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">T\u00f6rnqvist, T. E., B. E. Rosenheim, P. Hu, and A. B. Fernandez. 2015. \u201cRadiocarbon Dating and Calibration.\u201d In <em>Handbook of Sea-Level Research<\/em>, edited by Ian Shennan, Antony J. Long, and Benjamin P. Horton, 347-360. Oxford, UK: John Wiley &amp; Sons. <a class=\"rId140\" href=\"https:\/\/doi.org\/10.1002\/9781118452547.ch23\">https:\/\/doi.org\/10.1002\/9781118452547.ch23<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">University of Arizona. n.d. \u201cUranium-Thorium Dating: The Uranium 238 Decay Series.\u201d Accessed November 21, 2022. <a class=\"rId141\" href=\"https:\/\/www.geo.arizona.edu\/Antevs\/ecol438\/uthdating.html\">https:\/\/www.geo.arizona.edu\/Antevs\/ecol438\/uthdating.html<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">University of the Witwatersrand. 2017. \u201cLittle Foot Takes a Bow: South Africa\u2019s Oldest and the World\u2019s Most Complete <em>Australopithecus<\/em> Skeleton Ever Found, Introduced to the World.\u201d <em>ScienceDaily<\/em>, December 6. Accessed February 14, 2023. <a class=\"rId142\" href=\"https:\/\/www.sciencedaily.com\/releases\/2017\/12\/171206100104.htm\">https:\/\/www.sciencedaily.com\/releases\/2017\/12\/171206100104.htm<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">van Calsteren, Peter, and Louise Thomas. 2006. \u201cUranium-Series Dating Applications in Natural Environmental Science.\u201d <em>Earth-Science Reviews<\/em> 75 (1\u20134): 155\u2013175.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Vanzetti, A., M. Vidale, M. Gallinaro, D. W. Frayer, and L. Bondioli. 2010. \u201cThe Iceman as a Burial.\u201d <em>Antiquity<\/em> 84 (325): 681\u2013692. <a class=\"rId143\" href=\"https:\/\/doi.org\/10.1017\/S0003598X0010016X\">https:\/\/doi.org\/10.1017\/S0003598X0010016X<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Verghese, Namrata. 2021. \u201cWhat Is Necropolitics? The Political Calculation of Life and Death.\u201d <em>Teen Vogue<\/em>. March 10, 2021. Accessed February 14, 2023. https:\/\/www.teenvogue.com\/story\/what-is-necropolitics.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Vidale, M., L. Bondioli, D. W. Frayer, M. Gallinaro, and A. Vanzetti. 2016. \u201c\u00d6tzi the Iceman.\u201d <em>Expedition<\/em> 58 (2): 13\u201317. Accessed February 14, 2023. <a class=\"rId144\" href=\"https:\/\/www.penn.museum\/sites\/expedition\/otzi-the-iceman\/\">https:\/\/www.penn.museum\/sites\/expedition\/otzi-the-iceman\/<\/a>.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wade, Lizzie. 2021. \"Footprints Support Claim of Early Arrival in the Americas.\" <em>Science <\/em>373 (6562): 1426. Accessed February 14, 2023. https:\/\/www.sciencemagazinedigital.org\/sciencemagazine\/24_september_2021\/MobilePagedArticle.action?articleId=1727132#articleId1727132.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Waters, Colin N., Jan Zalasiewicz, Anthony D. Barnosky, Alejandro Cearreta, Agieszka Galuszka, Juliana A. Ivar Do Sul, Catherine Jeandel, et al. 2016 \u201cIs the Anthropocene Distinct from the Holocene?\u201d <em>Science <\/em>351 (6269): aad2622-1-10. DOI:<a class=\"rId145\" href=\"https:\/\/dx.doi.org\/10.1126\/science.aad2622\">10.1126\/science.aad2622<\/a><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Watson, Traci. 2017. \u201cAncient Bones Reveal Girl\u2019s Tough Life in Early Americas.\u201d <em>Nature <\/em>544 (7648): 15\u201316<em>. <\/em><\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wendt, Kathleen, A., Xianglei Li,, and R. Lawrence Edwards. 2021. \u201cUranium-Thorium Dating of Speleothems.\u201d Elements 17 (2): 87\u201392.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">White, Tim D. 1986. \u201cCut Marks on the Bodo Cranium: A Case of Prehistoric Defleshing.\u201d <em>American Journal of Physical Anthropology<\/em> 69 (4): 503\u2013509.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Williams, Linda D. 2004. <em>Earth Science Demystified<\/em>. New York: McGraw-Hill Professional.<\/p>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wilson, Andrew S., Timothy Taylor, Maria Constanza Ceruti, Jose Antonio Chavez, Johan Reinhard, Vaughan Grimes, Wolfram Meier-Augenstein, et al. 2007. \u201cStable Isotope and DNA Evidence for Ritual Sequences in Inca Child Sacrifice.\u201d <em>PNAS<\/em> 104 (42): 16456\u201316461.<\/p>\r\n\r\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Acknowledgments<\/h2>\r\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">We are grateful to Lee Anne Zajicek, who coauthored the first edition. Her original contributions continue to be an integral part of this chapter. We thank the staff of the Maturango Museum, Ridgecrest, California. Specifically, for their generous help with photography and fossil images, we acknowledge Debbie Benson, executive director; Alexander K. Rogers, former archaeology curator; Sherry Brubaker, natural history curator; and Elaine Wiley, history curator. We thank Sharlene Paxton, a librarian at Cerro Coso Community College, Ridgecrest, California, for her guidance and expertise with OER and open-source images, and John Stenger-Smith and Claudia Sellers from Cerro Coso Community College, Ridgecrest, California, for their feedback on the chemistry and plant biology content. Finally, we thank William Zajicek and Lauren Zajicek, our community college students, for providing their impressions and extensive feedback on early drafts of the chapter.<\/p>\r\n\r\n<\/div>","rendered":"<div class=\"__UNKNOWN__\">\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Sarah S. King, Ph.D., Cerro Coso Community College<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Kara Jones, M.A., Ph.D. student, University of Nevada Las Vegas<\/p>\n<p class=\"import-Normal\"><em>This chapter<\/em><em> is a revision from &#8220;<\/em><a class=\"rId6\" href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\"><em>Chapter 7: Understanding the Fossil Context<\/em><\/a><em>\u201d by Sarah King and Lee Anne Zajicek. <\/em><em>In <\/em><a class=\"rId7\" 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=\"rId8\" 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: #ffffff;\">Learning Objectives<\/span><\/h2>\n<\/header>\n<div class=\"textbox__content\">\n<ul>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Identify the different types of fossils and describe how they are formed.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Discuss relative and chronometric dating methods, the type of material they analyze, and their applications.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Describe the methods used to reconstruct past environments.<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">Interpret a site using the methods described in this chapter.<\/li>\n<\/ul>\n<\/div>\n<\/div>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossil Study: An Evolving Process<\/h2>\n<h3 class=\"import-Normal\"><strong>Mary Anning and the Age of Wonder<\/strong><\/h3>\n<figure style=\"width: 206px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/05\/image12.jpg\" alt=\"Woman points to dog and fossil on the ground.\" width=\"206\" height=\"248\" \/><figcaption class=\"wp-caption-text\">Figure 7.1: An oil painting of Mary Anning and her dog, Tray, prior to 1845. The \u201cJurassic Coast\u201d of Lyme Regis is in the background. Notice that Anning is pointing at a fossil. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Mary_Anning_by_B._J._Donne.jpg\">Mary Anning by B. J. Donne<\/a> from the Geological Society\/NHMPL is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p>Mary Anning (1799\u20131847) is likely the most famous fossil hunter you\u2019ve never heard of (Figure 7.1). Anning lived her entire life in Lyme Regis on the Dorset coast in England. As a woman, born to a poor family, with minimal education (even by 19th-century standards), the odds were against Anning becoming a scientist (Emling 2009, xii). It was remarkable that Anning was eventually able to influence the great scientists of the day with her fossil discoveries and her subsequent hypotheses regarding evolution.<\/p>\n<p class=\"import-Normal\">The time when Anning lived was a remarkable period in human history because of the Industrial Revolution in Britain. Moreover, the scientific discoveries of the 18th and 19th centuries set the stage for great leaps of knowledge and understanding about humans and the natural world. Barely a century earlier, Sir Isaac Newton had developed his theories on physics and become the president of the Royal Society of London (Dolnick 2011, 5). In this framework, the pursuit of intellectual and scientific discovery became a popular avocation for many individuals, the vast majority of whom were wealthy men (Figure 7.2).<\/p>\n<figure style=\"width: 358px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image22-1.png\" alt=\"Robed figure near a rock structure.\" width=\"358\" height=\"273\" \/><figcaption class=\"wp-caption-text\">Figure 7.2: A Walk at Dusk, 1830\u20131835, by Caspar David Friedrich, is a painting likely of a dolmen, a megalithic (large rock) tomb. Dolmens were built throughout Europe, five to six thousand years ago. Scholars were fascinated by the ancient world, which was an accepted part of Earth\u2019s history, even if explanation defied nonsecular thought. Credit: <a href=\"https:\/\/www.getty.edu\/art\/collection\/object\/103RJX\">A Walk at Dusk object 93.PA.14<\/a> by Casper David Friedrich German, 1774\u20131840, Paul Getty Museum, is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a> and part of the <a href=\"https:\/\/www.getty.edu\/projects\/open-content-program\/\">Getty Open Content Program<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">In spite of the expectations of Georgian English society to the contrary, Anning became a highly successful fossil hunter as well as a self-educated geologist and anatomist. The geology of Lyme Regis, with its limestone cliffs, provided a fortuitous backdrop for Anning\u2019s lifework. Now called the \u201cJurassic Coast,\u201d Lyme Regis has always been a rich source for fossilized remains (Figure 7.3). Continuing her father\u2019s passion for fossil hunting, Anning scoured the crumbling cliffs after storms for fossilized remains and shells. The work was physically demanding and downright dangerous. In 1833, while searching for fossils, Anning lost her beloved dog in a landslide and nearly lost her own life in the process (Emling 2009).<\/p>\n<figure style=\"width: 283px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image14-1.jpg\" alt=\"Rocky coastline and cliffs.\" width=\"283\" height=\"212\" \/><figcaption class=\"wp-caption-text\">Figure 7.3: The \u201cJurassic Coast\u201d of Lyme Regis: the home of fossil hunter Mary Anning. Credit: <a href=\"https:\/\/pixabay.com\/photos\/lyme-regis-coast-sea-cliffs-924431\/\">Lyme-regis-coast-sea-cliffs-924431<\/a> by <a href=\"https:\/\/pixabay.com\/users\/jstarj-884623\/\">jstarj<\/a> has been designated to the <a href=\"https:\/\/creativecommons.org\/share-your-work\/public-domain\/cc0\/\">public domain (CC0)<\/a> under a <a href=\"https:\/\/pixabay.com\/service\/terms\/#license\">Pixabay License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">Around the age of ten, Anning located and excavated a complete fossilized skeleton of an ichthyosaurus (\u201cfish lizard\u201d). She eventually found <em>Pterodactylus macronyx<\/em> and a 2.7-meter <em>Plesiosaurus<\/em>, considered by many to be her greatest discovery (Figure 7.4). These discoveries proved that there had been significant changes in the way living things appeared throughout the history of the world. Like many of her peers, including Darwin, Anning had strong religious convictions. However, the evidence that was being found in the fossil record was contradictory to the Genesis story in the Bible. In <em>The Fossil Hunter: Dinosaurs, Evolution, and the Woman Whose Discoveries Changed the World<\/em>, Anning\u2019s biographer Shelley Emling (2009, 38) notes, \u201cthe puzzling attributes of Mary\u2019s fossil [ichthyosaurus] struck a blow at this belief and eventually helped pave the way for a real understanding of life before the age of humans.\u201d<\/p>\n<figure style=\"width: 247px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image21.png\" alt=\"Plesiosaurus drawing.\" width=\"247\" height=\"375\" \/><figcaption class=\"wp-caption-text\">Figure 7.4: Plesiosaurus, illustrated and described by Mary Anning in an undated handwritten letter. Credit: <a href=\"https:\/\/wellcomecollection.org\/works\/cezbevj4\">Autograph letter concerning the discovery of plesiosaurus<\/a> by Mary Anning (1799\u20131847) from the <a href=\"https:\/\/wellcomecollection.org\">Wellcome Collection<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/\">CC BY 4.0 License<\/a>.<\/figcaption><\/figure>\n<p>Intellectual and scientific debate now had physical evidence to support the theory of evolution, which would eventually result in Darwin\u2019s seminal work,<em> On the Origin of Species<\/em> (1859). Anning\u2019s discoveries and theories were appreciated and advocated by her friends, intellectual men who were associated with the Geological Society of London. Regrettably, this organization was closed to women, and Anning received little official recognition for her contributions to the fields of natural history and paleontology. It is clear that Anning\u2019s knowledge, diligence, and uncanny luck in finding magnificent specimens of fossils earned her unshakeable credibility and made her a peer to many antiquarians (Emling 2009).<\/p>\n<p class=\"import-Normal\">Fossil hunting is still providing evidence and a narrative of the story of Earth. Mary Anning recognized the value of fossils in understanding natural history and relentlessly championed her theories to the brightest minds of her day. Anning\u2019s ability to creatively think \u201coutside the box\u201d\u2014skillfully assimilating knowledge from multiple academic fields\u2014was her gift to our present understanding of the fossil record. Given how profoundly Anning has shaped how we, in the modern day, think about the origins of life, it is surprising that her contributions have been so marginalized. Anning\u2019s name should be on the tip of everyone\u2019s tongue. Fortunately, at least in one sense of the word, it is. The well-known tongue twister, below, may have been written about Mary Anning:<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">She sells sea-shells on the sea-shore.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">The shells she sells are sea-shells, I\u2019m sure.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">For if she sells sea-shells on the sea-shore<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">Then I\u2019m sure she sells sea-shore shells.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 130.5pt; text-indent: 36pt;\">\u2014T. Sullivan (1908)<\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Developing Modern <\/strong><strong>Methods<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As Mary Anning\u2019s story suggests, scientists in Europe were working at a time dominated by western Christian tradition. Literal interpretations of the bible did not allow for the long, slow processes of geological or evolutionary change to operate. However, many scientists were making observations that did not fit the biblical narrative. During the 18th century, Scotsman James Hutton\u2019s work on the formation of Earth provided a much longer timeline of events than previous biblical interpretations would allow. Hutton\u2019s theory of <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_826\">Deep Time<\/a><\/strong> was crucial to the understanding of fossils. Deep Time gave the history of Earth enough time\u20144.543 billion years\u2014to encompass <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_828\">continental drift<\/a><\/strong>, the evolution of species, and the fossilization process. A second Scotsman, Charles Lyell, propelled Hutton\u2019s work into his own theory of <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_830\">uniformitarianism<\/a><\/strong>, the doctrine that Earth\u2019s geologic formations are the work of slow geologic forces. Lyell\u2019s three-volume work, <em>Principles of Geology<\/em> (1830\u20131833), was influential to naturalist Charles Darwin (see Chapter 2 for more information on Darwin\u2019s work). In fact, Lyell\u2019s first volume accompanied Darwin on his five-year voyage around the world on the <em>HMS Beagle<\/em> (1831\u20131836). The concepts proposed by Lyell gave Darwin an opportunity to apply his working theories of evolution by natural selection and a greater length of time with which to work. These resulting theories were important scientific discoveries and paved the way for the \u201cAge of Wonder\u201d (Holmes 2010, xvi).<\/p>\n<figure style=\"width: 264px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image30-1.jpg\" alt=\"Fossilized shell.\" width=\"264\" height=\"176\" \/><figcaption class=\"wp-caption-text\">Figure 7.5: Murexsul (Miocene): This fossil was found at the Naval Weapons Center, China Lake, California, in 1945. The fossil was buried deep in the strata and was pulled out of the ground along with a crashed \u201cFat Boy\u201d missile after atomic missile testing (S. Brubaker, personal communication, March 9, 2018). Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Murexsul (Figure 7.6)<\/a> from the <a href=\"https:\/\/maturango.org\/\">Maturango Museum<\/a>, Ridgecrest, California, by Sarah S. King and Lee Anne Zajicek is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p>The work of Anning, Darwin, Lyell, and many others laid the foundation for the modern methods we use today. Though anthropology is focused on humans and our primate relatives (and not on dinosaurs, as many people wrongly assume), you will see that methods developed in paleontology, geology, chemistry, biology, and physics are often applied in anthropological research. In this chapter, you will learn about the primary methods and techniques employed by biological anthropologists to answer questions about <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_832\">fossils<\/a><\/strong>, the mineralized copies of once-living organisms (Figure 7.5). Ultimately, these answers provide insights into human evolution. Pay close attention to ways in which modern biological anthropologists use other disciplines to analyze evidence and reconstruct past activities and environments.<\/p>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Earth: It&#8217;s Older than Dirt<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Scientists have developed precise and accurate dating methods based on work in the fields of physics and chemistry. Using these methods, scientists are able to establish the age of Earth as well as approximate ages of the organisms that have lived here. Earth is roughly 4.6 billion years old, give or take a few hundred million years. The first evidence for a living organism appeared around 3.5 billion years ago (<strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_844\">bya<\/a><\/strong>)<strong>.<\/strong> The scale of geologic time can seem downright overwhelming. In order to organize and make sense of Earth\u2019s past, geologists break up that time into subunits, which are human-made divisions along Earth\u2019s timeline. The largest subunit is the <strong>eon. <\/strong>An eon is further divided into <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_836\">eras<\/a>,<\/strong> and eras are divided into <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_838\">periods<\/a><\/strong>. Finally, periods are divided into <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_846\">epochs<\/a><\/strong> (see Figure 7.6; Williams 2004, 37). Currently, we are living in the Phanerozoic eon, Cenozoic era, Quaternary period, and probably the Holocene epoch\u2014though there is academic debate about the current epoch (see below).<\/p>\n<figure id=\"attachment_248\" aria-describedby=\"caption-attachment-248\" style=\"width: 1134px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-227 size-full\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17.jpeg\" alt=\"Table of geological time scale and examples. Full text link in caption.\" width=\"1134\" height=\"1300\" srcset=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17.jpeg 1134w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17-262x300.jpeg 262w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17-893x1024.jpeg 893w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17-768x880.jpeg 768w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17-65x75.jpeg 65w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17-225x258.jpeg 225w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/Geo-Time-Scale-FY17-350x401.jpeg 350w\" sizes=\"auto, (max-width: 1134px) 100vw, 1134px\" \/><figcaption id=\"caption-attachment-248\" class=\"wp-caption-text\">Figure 7.6: The Geologic time scale is shown here, with periods broken into eons, eras, periods, and in some cases epochs. Some life forms and geological events are noted for each period. <a href=\"https:\/\/docs.google.com\/document\/d\/1VUDKMBJYS_jNONjLxT04jQN0_z9Ua50BRN6auGSHUuU\/edit\">A full text description of this image is available<\/a>. Credit: <a href=\"https:\/\/www.nps.gov\/subjects\/geology\/time-scale.htm\" target=\"_blank\" rel=\"noopener\">Geologic Time Scale<\/a>, by <a href=\"https:\/\/www.nps.gov\/index.htm\" target=\"_blank\" rel=\"noopener\">National Park Service<\/a>, designed by Trista Thornberry-Ehrlich and Rebecca Port, adapted from ones from <a href=\"https:\/\/www.usgs.gov\/\" target=\"_blank\" rel=\"noopener\">USGS<\/a> and the International Commission on Stratigraphy, is in the <a href=\"https:\/\/www.nps.gov\/aboutus\/disclaimer.htm#:~:text=%C2%A7%C2%A7%20101%2C%20105)\" target=\"_blank\" rel=\"noopener\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">These divisions are based on major changes and events recorded in the geologic record. Events like significant shifts in climate or mass extinctions can be used to mark the end of one geologic time unit and the beginning of another. However, it is important to remember that these borders are not real in a physical sense; they are helpful organizational guidelines for scientific research. There can be debate regarding how the boundaries are defined. Additionally, the methods we use to establish these dates are refined over time, occasionally leading to shifts in established chronology (see the discussion on calibration in the radiocarbon dating section below). For instance, the current epoch has been traditionally known as the <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_840\">Holocene<\/a><\/strong>. It began almost twelve thousand years ago (<strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_842\">kya<\/a><\/strong>) during the warming period after that last major ice age. Today, there is evidence to indicate human-driven climate change is warming the world and changing the environmental patterns faster than the natural cyclical processes. This has led some scientists within the stratigraphic community to argue for a new epoch beginning around 1950 with the Nuclear Age called the <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_848\">Anthropocene<\/a> <\/strong>(Monastersky 2015; Waters et al. 2016). Nobel Laureate Paul Crutzen places the beginning of the Anthropocene much earlier\u2014at the dawn of the Industrial Revolution, with its polluting effects of burning coal (Crutzen and Stoermer 2000, 17\u201318). Geologist William Ruddiman argues that the epoch began 5,000\u20138,000 years ago with the advent of agriculture and the buildup of early methane gasses (Ruddiman et al. 2008). Regardless of when the Anthropocene started, the major event that marks the boundary is the warming temperatures and mass extinction of nonhuman species caused by human activity (Figure 7.7). Researchers now declare that \u201chuman activity now rivals geologic forces in influencing the trajectory of the Earth System\u201d (Steffen et al. 2018, 1).<\/p>\n<figure style=\"width: 299px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image1.jpg\" alt=\"Two cylindrical towers emitting white steam.\" width=\"299\" height=\"168\" \/><figcaption class=\"wp-caption-text\">Figure 7.7: The Chooz Nuclear Power, in a valley in Ardennes, France, is a reminder that human activity affects the planet greatly. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Chooz_Nuclear_Power_Plant-9361.jpg\">Chooz Nuclear Power Plant-9361<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Raymond\">Raimond Spekking<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.<\/figcaption><\/figure>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossils: The Taphonomic Process<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Most of the evidence of human evolution comes from the study of the dead. To obtain as much information as possible from the remains of once-living creatures, one must understand the processes that occur after death. This is where <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_850\">taphonomy<\/a><\/strong> comes in (Figure 7.8). Taphonomy is the study of what happens to an organism after death (Komar and Buikstra 2008, 189; Stodder 2008). It includes the study of how an organism becomes a fossil. However, as you\u2019ll see throughout this book, the majority of organisms never make it through the full fossilization process.<\/p>\n<figure style=\"width: 261px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image25-1.jpg\" alt=\"Coyote skull with bones and fur.\" width=\"261\" height=\"348\" \/><figcaption class=\"wp-caption-text\">Figure 7.8: Taphonomy focuses on what happens to the remains of an organism, like this coyote, after death. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Coyote remains (Figure 7.14)<\/a> by Sarah S. King is under a <a 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;\">Taphonomy is important in biological anthropology, especially in subdisciplines like bioarchaeology (the study of human remains in the archaeological record) and zooarchaeology (the study of faunal remains from archaeological sites). It is so important that many scientists have recreated a variety of burial and decay experiments to track taphonomic change in modern contexts. These contexts can then be used to understand the taphonomic patterns seen in the fossil record (see Reitz and Wing 1999, 122\u2013141).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taphonomic analysis can also give us important insights into the development of complex thought and ritual in human evolution. In Chapter 11, you will see the first evidence of recognized burial practices in hominins. Taphonomy helped to establish whether these burials were simply the result of natural processes or intentionally constructed by humans (Klein 1999, 395; Straus 1989). Deliberate burials often include the body placed in a specific position, such as supine (on the back) with arms crossed over the chest or in a flexed position (think fetal position) facing a particular direction. If bones have evidence of a carnivore or rodent gnawing on them, it can be inferred that the remains were exposed to scavengers after death.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Going back further in time, taphonomic evidence may tell us how our ancestors died. For instance, several australopithecine fossils show evidence of carnivore tooth marks and even punctures from saber-toothed cats, indicating that we weren\u2019t always the top of the food chain. The Bodo Cranium, a <em>Homo erectus<\/em> cranium from Middle Awash Valley, Ethiopia, shows cut marks made by stone tools, indicating an early example of possible defleshing activity in our human ancestors (White 1986). At the archaeological site of Zhoukoudian, researchers used taphonomy to show that the highly fragmented remains of at least 51 <em>Homo erectus<\/em> individuals were scavenged by Pleistocene cave hyenas (Boaz et al. 2004). The damage on Skull VI was described as \u201celongated, raking bite marks, isolated puncture bite marks, and perimortem breakage consistent with patterns of modern hyaenid bone modification\u201d (Boaz et al. 2004). Additionally, a fresh burnt equid cranium was discovered which supports the theory of mobile hominid scavenging and fire use at the site (Boaz et al. 2004).<\/p>\n<div class=\"textbox\">\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Special Topic: Bog Bodies and Mummies <span style=\"text-decoration: underline;\">(Add a picture to show how well preserved they are!)<\/span><\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Preservation is a key topic in anthropological research, since we can only study the evidence that gets left behind in the fossil and archaeological record. This chapter is concerned with the fossil record; however, there are other forms of preserved remains that provide anthropologists with information about the past. You\u2019ve undoubtedly heard of mummification, likely in the context of Egyptian or South American mummies. However, bog bodies and ice mummies are further examples of how remains can be preserved in special circumstances. It is important to note that fossilization is a process that takes much longer than the preservation of bog bodies or mummies.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Bog bodies are good examples of wetland preservation. Peat bogs are formed by the slow accumulation of vegetation and silts in ponds and lakes. Individuals were buried in bogs throughout Europe as far back as 10 kya, with a proliferation of activity from 1,600 to 3,200 years ago (Giles 2020; Ravn 2010). When they were found thousands of years later, they resembled recent burials. Their hair, skin, clothing, and organs were exceptionally well preserved, in addition to their bones and teeth (Eisenbeiss 2016; Ravn 2010). Preservation was so good in fact that archaeologists could identify the individuals\u2019 last meals and re-create tattoos found on their skin.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Extreme cold can also halt the natural decay process. A well-known ice mummy is \u00d6tzi, a Copper Age man dating to around 5,200 years ago found in the Alps (Vanzetti et al. 2012; Vidale et al. 2016). As with the bog bodies, his hair, skin, clothing, and organs were all well preserved. Recently, archaeologists were able to identify his last meal (Maixner et al. 2018). It was high in fat, which makes sense considering the extremely cold environment in which he lived, as meals high in fat assist in cold tolerance (Fumagalli et al. 2015).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">In the Andes, ancient peoples would bury human sacrifices throughout the high peaks in a sacred ritual called Capacocha (Wilson et al. 2007). The best-preserved mummy to date is called the \u201cMaiden\u201d or \u201cSarita\u201d because she was found at the summit of Sara Sara Volcano. Her remains are over 500 years old, but she still looks like the 15-year-old girl she was at the time of her death, as if she had just been sleeping for 500 years (Reinhard 2006).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Finally, arid environments can also contribute to the preservation of organic remains. As discussed with waterlogged sites, much of the bacteria that is active in breaking down bodies is already present in our gut and begins the putrefaction process shortly after death. Arid environments deplete organic material of the moisture that putrefactive bacteria need to function (Booth et al. 2015). When that occurs, the soft tissue like skin, hair, and organs can be preserved. It is similar to the way a food dehydrator works to preserve meat, fruit, and vegetables for long-term storage. There are several examples of arid environments spontaneously preserving human remains, including catacomb burials in Austria and Italy (Aufderheide 2003, 170, 192\u2013205).<\/p>\n<\/div>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossilization<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fossils only represent a tiny fraction of creatures that existed in the past. It is extremely difficult for an organism to become a fossil. After all, organisms are designed to deteriorate after they die. Bacteria, insects, scavengers, weather, and environment all aid in the process that breaks down organisms so their elements can be returned to Earth to maintain ecosystems (Stodder 2008). <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_852\">Fossilization<\/a><\/strong>, therefore, is the preservation of an organism against these natural decay processes (Figure 7.9).<\/p>\n<figure style=\"width: 699px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image20-2.png\" alt=\"Five images depicting fossilization.\" width=\"699\" height=\"345\" \/><figcaption class=\"wp-caption-text\">Figure 7.9: A simplified illustration of the fossilization process beginning at an organism&#8217;s death. In this example, the individual begins to decompose and then is covered by water and sediments, both protecting it and creating an environment for perimineralization. Sediments accumulate over time. Erosion eventually exposes the fossil, leading to its eventual discovery by paleoanthropologists. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Fossilization process (Figure 7.15)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">For fossilization to occur, several important things must happen. First, the organism must be protected from things like bacterial activity, scavengers, and temperature and moisture fluctuations. A stable environment is important. This means that the organism should not be exposed to significant fluctuations in temperature, humidity, and weather patterns. Changes to moisture and temperature cause the organic tissues to expand and contract repeatedly, which will eventually cause microfractures and break down (Stodder 2008). Soft tissue like organs, muscle, and skin are more easily broken down in the decay process; therefore, they are less likely to be preserved. Bones and teeth, however, last much longer and are more common in the fossil record (Williams 2004, 207).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wetlands are a particularly good area for preservation because they allow for rapid permanent burial and a stable moisture environment. That is why many fossils are found in and around ancient lakes and river systems. Waterlogged sites can also be naturally <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_854\">anaerobic<\/a><\/strong> (without oxygen). Much of the bacteria that causes decay is already present in our gut and can begin the decomposition process shortly after death during putrefaction (Booth et al. 2015). Since oxygen is necessary for the body\u2019s bacteria to break down organic material, the decay process is significantly slowed or halted in anaerobic conditions.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The next step in the fossilization process is sediment accumulation. The sediments cover and protect the organism from the environment. They, along with water, provide the minerals that will eventually become the fossil (Williams 2004, 31). Sediment accumulation also provides the pressure needed for mineralization to take place. <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_856\">Lithification<\/a><\/strong> is when the weight and pressure of the sediments squeeze out extra fluids and replace the voids that appear with minerals from the surrounding sediments. Finally, we have <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_858\">permineralization<\/a><\/strong>. This is when the organism is fully replaced by minerals from the sediments. A fossil is really a mineral copy of the original organism (Williams 2004, 31).<\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Types of Fossils<\/strong><\/h3>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Plants<\/em><\/h4>\n<figure style=\"width: 259px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image2-1.jpg\" alt=\"Petrified wood.\" width=\"259\" height=\"194\" \/><figcaption class=\"wp-caption-text\">Figure 7.10: An exquisite piece of petrified wood. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:PetrifiedWood.jpg\">PetrifiedWood<\/a> at the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Petrified_Forest_National_Park\">Petrified Forest National Park<\/a> by <a href=\"https:\/\/pdphoto.org\/\">Jon Sullivan<\/a> has been designated to the <a 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;\">Plants make up the majority of fossilized materials. One of the most common plants existing today, the fern, has been found in fossilized form many times. Other plants that no longer exist or the early ancestors of modern plants come in fossilized forms as well. It is through these fossils that we can discover how plants evolved and learn about the climate of Earth over different periods of time.<\/p>\n<p>Another type of fossilized plant is <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_860\">petrified wood<\/a><\/strong>. This fossil is created when actual pieces of wood\u2014such as the trunk of a tree\u2014mineralize and turn into rock. Petrified wood is a combination of silica, calcite, and quartz, and it is both heavy and brittle. Petrified wood can be colorful and is generally aesthetically pleasing because all the features of the original tree\u2019s composition are illuminated through mineralization (Figure 7.10). There are a number of places all over the world where petrified wood \u201cforests\u201d can be found, but there is an excellent assemblage in Arizona, at the Petrified Forest National Park. At this site, evidence relating to the environment of the area some 225 <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_862\">mya<\/a><\/strong> is on display.<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Human\/Animal Remains<\/em><\/h4>\n<figure style=\"width: 242px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image7-1.jpg\" alt=\"Partial hominin skeleton on black background.\" width=\"242\" height=\"583\" \/><figcaption class=\"wp-caption-text\">Figure 7.11: \u201cLucy\u201d (AL 288-1), Australopithecus afarensis. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Lucy_blackbg.jpg\">Lucy blackbg<\/a> by 120 is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/2.5\/deed.en\">CC BY 2.5 License<\/a>.<\/figcaption><\/figure>\n<p>We are more familiar with the fossils of early animals because natural history museums have exhibits of dinosaurs and extinct mammals. However, there are a number of fossilized hominin remains that provide a picture of the fossil record over the course of our evolution from primates. The term <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_800\">hominins<\/a><\/strong> includes all human ancestors who existed after the evolutionary split from chimpanzees and bonobos, some six to seven mya. Modern humans are <em>Homo sapiens<\/em>, but hominins can include much earlier versions of humans. One such hominin is \u201cLucy\u201d (AL 288-1), the 3.2 million-year-old fossil of <em>Australopithecus afarensis<\/em> that was discovered in Ethiopia in 1974 (Figure 7.11). Until recently, Lucy was the most complete and oldest hominin fossil, with 40% of her skeleton preserved (see Chapter 9 for more information about Lucy). In 1994, an <em>Australopithecus<\/em> fossil nicknamed \u201cLittle Foot\u201d (Stw 573) was located in the World Heritage Site at Sterkfontein Caves (\u201cthe Cradle of Humankind\u201d) in South Africa. Little Foot is more complete than Lucy and possibly the oldest fossil that has so far been found, dating to at least 3.6 million years (Granger et al. 2015). The ankle bones of the fossil were extricated from the matrix of concrete-like rock, revealing that the bones of the ankles and feet indicate bipedalism (University of Witwatersrand 2017).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Both the Lucy and Little Foot fossils date back to the Pliocene (5.8 to 2.3 mya). Older hominin fossils from the late Miocene (7.25 to 5.5 mya) have been located, although they are much less complete. The oldest hominin fossil is a fragmentary skull named <em>Sahelanthropus tchadensis<\/em>, found in Northern Chad and dating to circa seven mya (Lebatard et al. 2008). It is through the discovery, dating, and study of primate and early hominin fossils that we find physical evidence of the evolutionary timeline of humans.<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Asphalt<\/em><\/h4>\n<figure style=\"width: 510px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image28.jpg\" alt=\"Asphalt lake with mammoth figurines.\" width=\"510\" height=\"340\" \/><figcaption class=\"wp-caption-text\">Figure 7.12: This is a recreation of how animals tragically came to be trapped in the asphalt lake at the La Brea Tar Pits. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Mammoth_Tragedy_at_La_Brea_Tar_Pits_(5463657162).jpg\">Mammoth Tragedy at La Brea Tar Pits (5463657162)<\/a> by <a href=\"https:\/\/www.flickr.com\/people\/81943113@N00\">KimonBerlin<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/2.0\/legalcode\">CC BY-SA 2.0 License<\/a>.<\/figcaption><\/figure>\n<figure style=\"width: 206px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image6-3.jpg\" alt=\"Skull with open jaw and large teeth.\" width=\"206\" height=\"245\" \/><figcaption class=\"wp-caption-text\">Figure 7.13: The fearsome jaws of the saber-toothed cat (Smilodon fatalis) found at the La Brea Tar Pits. Credit: <a href=\"https:\/\/www.flickr.com\/photos\/jsjgeology\/15256884929\">Smilodon saber-toothed tiger skull (La Brea Asphalt, Upper Pleistocene; Rancho La Brea tar pits, southern California, USA) 1<\/a> by <a href=\"https:\/\/www.flickr.com\/photos\/jsjgeology\/\">James St. John<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/2.0\/\">CC BY 2.0 License<\/a>.<\/figcaption><\/figure>\n<p>Asphalt, a form of crude oil, can also yield fossilized remains. Asphalt is commonly referred to in error as tar because of its viscous nature and dark color. A famous fossil site from California is La Brea Tar Pits in downtown Los Angeles (Figure 7.12). In the middle of the busy city on Wilshire Boulevard, asphalt (not tar) bubbles up through seeps (cracks) in the sidewalk. The La Brea Tar Pits Museum provides an incredible look at the both extinct and extant animals that lived in the Los Angeles Basin 40,000\u201311,000 years ago. These animals became entrapped in the asphalt during the Pleistocene and perished in place. Ongoing excavations have yielded millions of fossils, including <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_864\">megafauna<\/a><\/strong> such as American mastodons and incomplete skeletons of extinct species of dire wolves, <em>Canis dirus<\/em>, and the saber-toothed cat, <em>Smilodon fatalis<\/em> (Figure 7.13). Fossilized remains of plants have also been found in the asphalt. The remains of one person have also been found at the tar pits. Referred to as La Brea Woman, the remains were found in 1914 and were subsequently dated to around 10,250 years ago. The La Brea Woman was a likely female individual who was 17\u201328 years old at the time of her death, with a height of under five feet (Spray 2022). She is thought to have died from blunt force trauma to her head, famously making her Los Angeles\u2019s first documented homicide victim (Spray 2022). (Learn more about her in the Special Topic box, \u201cNecropolitics,\u201d below.) Between the fossils of animals and those of plants, paleontologists have a good idea of the way the Los Angeles Basin looked and what the climate in the area was like many thousands of years ago.<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Igneous Rock<\/em><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Most fossils are found in sedimentary rock. This type of rock has been formed from deposits of minerals over millions of years in bodies of water on Earth\u2019s surface. Some examples include shale, limestone, and siltstone. Sedimentary rock typically has a layered appearance. However, fossils have been found in igneous rock as well. Igneous rock is volcanic rock that is created from cooled molten lava. It is rare for fossils to survive molten lava, and it is estimated that only 2% of all fossils have been found in igneous rock (Ingber 2012). Part of a giant rhinocerotid skull dating back 9.2 mya to the Miocene was discovered in Cappadocia, Turkey, in 2010. The fossil was a remarkable find because the eruption of the \u00c7ardak caldera was so sudden that it simply dehydrated and \u201cbaked\u201d the animal (Antoine et al. 2012).<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Trace Fossils<\/em><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Depending on the specific circumstances of weather and time, even footprints can become fossilized. Footprints fall into the category of <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_866\">trace fossils<\/a><\/strong>, which includes other evidence of biological activity such as nests, burrows, tooth marks, and shells. A well-known example of trace fossils are the Laetoli footprints in Tanzania (Figure 7.14). More recently, archaeological investigations in North America have revealed fossil footprints which rewrite the history of people in the Americas at White Sands, New Mexico. You can read more about the Laetoli and White Sands footprints in the Dig Deeper box below.<\/p>\n<figure style=\"width: 399px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image5-2.jpg\" alt=\"Uneven rock surface with footprints.\" width=\"399\" height=\"245\" \/><figcaption class=\"wp-caption-text\">Figure 7.14: A few early hominin footprints fossilized at Laetoli. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:NHM_-_Laetoli_Fu%C3%9Fspuren.jpg\">NHM &#8211; Laetoli Fu\u00dfspuren<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:Xenophon\">Wolfgang Sauber<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Other fossilized footprints have been discovered around the world. At Pech Merle cave in the Dordogne region of France, archaeologists discovered two fossilized footprints. They then brought in indigenous trackers from Namibia to look for other footprints. The approach worked, as many other footprints belonging to as many as five individuals were discovered with the expert eyes of the trackers (Pastoors et al. 2017). These footprints date back 12,000 years (Granger Historical Picture Archive 2018).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Some of the more unappealing but still-fascinating trace fossils are bezoars and coprolite. <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_868\">Bezoars<\/a><\/strong> are hard, concrete-like substances found in the intestines of fossilized creatures. Bezoars start off like the hair balls that cats and rabbits accumulate from grooming, but they become hard, concrete-like substances in the intestines. If an animal with a hairball dies before expelling the hair ball mass <em>and <\/em>the organism becomes fossilized, that mass becomes a bezoar.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_870\">Coprolite<\/a><\/strong> is fossilized dung. One of the best collections of coprolites is affectionately known as the \u201cPoozeum.\u201d The collection includes a huge coprolite named \u201cPrecious\u201d (Figure 7.15). Coprolite, like all fossilized materials, can be <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_872\">in matrix<\/a><\/strong>\u2014meaning that the fossil is embedded in secondary rock. As unpleasant as it may seem to work with coprolites, remember that the organic material in dung has mineralized or has started to mineralize; therefore, it is no longer soft and is generally not smelly. Also, just as a doctor can tell a lot about health and diet from a stool sample, anthropologists can glean a great deal of information from coprolite about the diets of ancient animals and the environment in which the food sources existed. For instance, 65 million-year-old grass <em>phytoliths<\/em> (microscopic silica in plants) found in dinosaur coprolite in India revealed that grasses had been in existence much earlier than scientists initially believed (Taylor and O\u2019Dea 2014, 133).<\/p>\n<figure style=\"width: 312px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image19-1-1.jpg\" alt=\"Piece of fossilized poop.\" width=\"312\" height=\"224\" \/><figcaption class=\"wp-caption-text\">Figure 7.15: An extremely large coprolite named \u201cPrecious.\u201d Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Precious_the_Coprolite_Courtesy_of_the_Poozeum.jpg\">Precious the Coprolite Courtesy of the Poozeum<\/a> by <a href=\"https:\/\/poozeum.com\">Poozeum<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.<\/figcaption><\/figure>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Pseudofossils<\/em><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_874\">Pseudofossils<\/a><\/strong> are not to be mistaken for fake fossils, which have vexed scientists from time to time. A fake fossil is an item that is deliberately manipulated or manufactured to mislead scientists and the general public. In contrast, pseudofossils are not misrepresentations but rather misinterpretations of rocks that look like true fossilized remains (S. Brubaker, personal communication, March 9, 2018). Pseudofossils are the result of impressions or markings on rock, or even the way other inorganic materials react with the rock. A common example is dendrites, the crystallized deposits of black minerals that resemble plant growth (Figure 7.16). Other examples of pseudofossils are unusual or odd-shaped rocks that include various concretions and nodules. An expert can examine a potential fossil to see if there is the requisite internal structure of organic material such as bone or wood that would qualify the item as a fossil.<\/p>\n<figure style=\"width: 426px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image29.jpg\" alt=\"Rock with black branching fractal veins.\" width=\"426\" height=\"284\" \/><figcaption class=\"wp-caption-text\">Figure 7.16: A beautiful example of dendrites, a type of pseudofossil. It\u2019s easy to see how the black crystals look like plant growth. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Dendrites (Figure 7.25)<\/a> from the <a href=\"https:\/\/maturango.org\/\">Maturango Museum<\/a>, Ridgecrest, California, by Sarah S. King and Lee Anne Zajicek is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<div class=\"textbox shaded\">\n<h2 class=\"import-Normal\">Dig Deeper: <del>Trace Fossils<\/del>\u00a0<em>The Power of Poop<\/em><\/h2>\n<p class=\"import-Normal\">Coprolites found in Paisley Caves, Oregon, in the United States are shedding new light on some of the earliest occupants in North America. Human coprolites are distinguished from animal coprolites through the identification of fecal biomarkers using lipids, or fats, and bile acids (Shillito et al. 2020a). Paisley Caves have 16,000 years of anthropogenic, or human-caused, deposition, with some coprolites having been dated as old as 12.8kya (Blong et al. 2020). Over 285 radiocarbon dates have been recorded from the site (Shillito et al. 2020a), making Paisley Caves one of the most well-dated archaeological sites in the United States. Coprolite analysis can be summarized in three levels, macroscopic, microscopic, and molecular. This can also be understood as analyzing the morphology (macroscopic), contents (microscopic), and residues (molecular) (Shillito et al. 2020b). Each of these levels adds a different layer of information. Coprolite shape is informative through what can be seen macroscopically, such as ingestions of basketry or cordage, small gravels and grains, and general shape. The contents of coprolites may be of the most interest to scientists because certain plants and animals can signal past environments as well as food procurement methods. Coprolites from Paisley Caves have included small pebbles and obsidian chips from butchering game, grinding plants, and general food preparation as well as small bits of fire cracked rock likely from cooking in hearths (Blong 2020). Additionally, rodent bones in coprolites included crania and vertebrae, which suggests whole consumption (Taylor et al. 2020). Insect remains are present in the coprolites as well, such as ants, Jerusalem crickets, June beetles, and darkling beetles (Blong 2020). In all, the coprolites of Paisley Caves have provided an invaluable resource to anthropologists to study the past climate and lifeways of early humans in the Americas.<\/p>\n<p class=\"import-Normal\">Coprolites can also signal past health, which is a study known as paleopathology. A study by Katelyn McDonough and colleagues (2022) focused on the identification of parasites in coprolites at Bonneville Estates Rockshelter in eastern Nevada and their link to the greater Great Basin during the Archaic, a period of time spanning 8,000\u20135,000 years ago. According to the study, parasites such as Acanthocephalans (thorny-headed worms) have been affecting the Great Basin for at least the last 10,000 years. Acanthocephalans are endoparasites, meaning parasites that live inside of their hosts. They are found worldwide and seem to have been concentrated in the Great Basin in the past. Bonneville Estates Rockshelter has been visited by humans for over 13,000 years, with parasite identification going back to nearly 7,000 years. The species identified at Bonneville Estates is <em>Moniliformis clarki<\/em>. This species parasitizes crickets and insects, a popular food source during the Archaic in the Great Basin. The parasite uses intermediate hosts to get to mammals and birds as definitive hosts. Crickets and beetles have been recorded as food materials in Paisley Caves as well. Insects have remained an important dietary staple for people of the Great Basin and are consumed raw, dried, brined, or ground into flour. Insects that remain uncooked or undercooked have a higher risk for transmission of parasites. Symptoms associated with Acanthocephalans infection are intense intestinal discomfort, anemia, and anorexia, leading to death. It is hypothesized that the consumption of basketry, cordage, and charcoal (which was also identified at Paisley Caves), sometimes associated with parasite-infected coprolites, may have been a method of treatment for the infection. Interestingly, present day infections from this parasite are rising after remaining quite rare, as detection of the parasite is occurring in insect farms.<\/p>\n<\/div>\n<h4 class=\"import-Normal\"><em>Walking to the Past<\/em><\/h4>\n<p class=\"import-Normal\">In 1974, British anthropologist Mary Leakey discovered fossilized animal tracks at Laetoli (Figure 7.17), not far from the important paleoanthropological site at Olduvai Gorge in Tanzania. A few years later, a 27-meter trail of hominin footprints were discovered at the same site. These 70 footprints, now referred to as the Laetoli Footprints, were created when early humans walked in wet volcanic ash. Before the impressions were obscured, more volcanic ash and rain fell, sealing the footprints. These series of environmental events were truly extraordinary, but they fortunately resulted in some of the most famous and revealing trace fossils ever found. Dating of the footprints indicate that they were made 3.6 mya (Smithsonian National Museum of Natural History 2018).<\/p>\n<figure style=\"width: 495px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image13-1-1.png\" alt=\"Eastern Africa map shows sites within Tanzania.\" width=\"495\" height=\"382\" \/><figcaption class=\"wp-caption-text\">Figure 7.17: Location of Laetoli site in Tanzania, Africa, with Olduvai Gorge nearby. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Laetoli and Olduvai Gorge sites (Figure 7.26)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">Just as forensic scientists can use footprints to identify the approximate build of a potential suspect in a crime, archaeologists have read the Laetoli Footprints for clues to these early humans. The footprints clearly indicate bipedal hominins who had similar feet to those of modern humans. Analysis of the gait through computer simulation revealed that the hominins at Laetoli walked similarly to the way we walk today (Crompton 2012). More recent analyses confirm the similarity to modern humans but also indicate a gait that involved more of a flexed limb than that of modern humans (Hatala et al. 2016; Raichlen and Gordon 2017). The relatively short stride implies that these hominins had short legs\u2014unlike the longer legs of later early humans who migrated out of Africa (Smithsonian National Museum of Natural History 2018). In the context of Olduvai Gorge, where fossils of <em>Australopithecus afarensis<\/em> have been located and dated to the same timeframe as the footprints, it is likely that these newly discovered impressions were left by these same hominins.<\/p>\n<p class=\"import-Normal\">The footprints at Laetoli were made by a small group of as many as three <em>Australopithecus afarensis<\/em>, walking in close proximity, not unlike what we would see on a modern street or sidewalk. Two trails of footprints have been positively identified with the third set of prints appearing smaller and set in the tracks left by one of the larger individuals. While scientific methods have given us the ability to date the footprints and understand the body mechanics of the hominin, additional consideration of the footprints can lead to other implications. For instance, the close proximity of the individuals implies a close relationship existed between them, not unlike that of a family. Due to the size variation and the depth of impression, the footprints seem to have been made by two larger adults and possibly one child. Scientists theorize that the weight being carried by one of the larger individuals is a young child or a baby (Masao et al. 2016). Excavation continues at Laetoli today, resulting in the discovery of two more footprints in 2015, also believed to have been made by <em>Au. afarensis<\/em> (Masao et al. 2016).<\/p>\n<figure style=\"width: 482px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image10.jpg\" alt=\"Map shows Tularosa Basin.\" width=\"482\" height=\"331\" \/><figcaption class=\"wp-caption-text\">Figure 7.18: Tularosa Basin, New Mexico. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:HUC1305.jpg\">Map of Tularosa Basin<\/a> by the <a href=\"https:\/\/www.usgs.gov\/\">United States Geological Survey<\/a> is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p>But it is not just human evolution studies that can benefit from the analysis of fossil footprints. A recent discovery of fossilized footprints has rewritten what we know about the peopling of the Americas. It was originally thought that humans had been in the Americas for at least the last 15,000 years by crossing through the ice-free corridor (IFC) between the Cordilleran and Laurentide ice sheets in present-day Alaska and Canada. However, fossil footprints from the Tularosa Basin of New Mexico (see Figure 7.18) discovered in 2021 have challenged this theory. The footprints, dated between 22,860 (\u2213320) and 21,130 (\u2213250) years ago (nps.gov) based on <em>Ruppia cirrhosa <\/em>grass seeds located above and below the footprints, have shown humans have been in the Americas for much longer than previously thought. These footprints represent an adolescent individual and toddler walking through the lakebed at White Sands (see Figure 7.19), New Mexico, alongside both giant ground sloths and mammoths (Barras 2022; Wade 2021). Also present in the lakebed are footprints of camels and dire wolves (nps.gov 2022; Wade 2021).<\/p>\n<figure style=\"width: 789px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image31-1.png\" alt=\"Archaeologists on ground. Excavation with footprints. Closeups of footprints.\" width=\"789\" height=\"594\" \/><figcaption class=\"wp-caption-text\">Figure 7.19: Excavation of fossil footprints from New Mexico. Credit: <a href=\"https:\/\/www.usgs.gov\/programs\/climate-research-and-development-program\/news\/discovery-ancient-human-footprints-white\">Images of White Sands National Park Study Site Footprints<\/a> by the <a href=\"https:\/\/www.usgs.gov\/programs\/climate-research-and-development-program\">USGS Climate Research and Development Program<\/a> is in the <a href=\"https:\/\/en.wikipedia.org\/wiki\/Public_domain\">public domain<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">The IFC model was upheld by a group of theorists known as \u201cClovis First,\u201d who believed the migration of people into the Americas was recent and was represented archaeologically through the Clovis projectile point toolkit. Subsequent discoveries at sites such as Cactus Hill on the east coast of the United States and Monte Verde, Chile, have demonstrated that this model wouldn\u2019t have worked. Because these sites are as old as 20,000 years and 18,500 years respectively, the IFC would have been frozen over and impassable (Gruhn 2020). Other models have been adopted to account for this, such as the coastal migration model down the west coast of North America. The more-likely migration scenario seems to be neither of these as more discoveries or antiquity continue to emerge. People may instead have migrated into the Americas before the last glacial maximum began, around 25,500\u201319,000 years ago. According to Indigenous knowledge, they have always been here. With the discovery of the White Sands footprints, it is known that humans have been in the Americas for at least 20,000 years.<\/p>\n<p class=\"import-Normal\">This discovery also reveals the importance of recognizing knowledge beyond that which is produced by the European scientific tradition. Rather than framing science in a way that runs counter to Indigenous knowledge, it can be thought that science is catching up with it. <span style=\"background-color: #00ffff;\">For instance, the Acoma Pueblo people have the word for <em>camel<\/em> in their vocabulary.<\/span> This was dismissed by scientists who assumed the word was for describing camels that were introduced to the United States in the past 100 years. However, the discovery of the White Sands footprints also included the footprints of Pleistocene camels in the same strata. Therefore, the fact that the Acoma Pueblo people have had a word for <em>camel<\/em> likely refers the Pleistocene-age megafauna camel, <em>Camelops hesternus,<\/em> rather than <em>Camelus dromedarius<\/em> or <em>Camelus bactrianus<\/em>, two present-day camel species (which are actually descendants of <em>Camelops hesternus<\/em>). Therefore, the existence of the Acoma Pueblo word for <em>camel <\/em>is not like an anomaly but rather a testament to the fact that Acoma Pueblo ancestors walked beside <em>C. hesternus<\/em> on this continent 20,000 years ago. These footprints challenge the \u201cice-free corridor\u201d expansion model, as the bridge connecting present-day Alaska and Russia into Canada would have been covered in an impenetrable ice sheet at this time. The discovery of these footprints urges scientists to reconsider further investigations at well-known Terminal Pleistocene\/Early Holocene dry lake beds in the Southwestern and Mojave deserts\u2014and to include Indigenous knowledge in their work rather than ignore it.<\/p>\n<div class=\"textbox\">\n<h2 class=\"import-Normal\">Special Topic: Necropolitics<\/h2>\n<p class=\"import-Normal\">What are necropolitics? Necropolitics is an application of critical theory that describes how \u201cgovernments assign differential value to human life\u201d and similarly how someone is treated after they die (Verghese 2021). How is someone\u2019s death political?<\/p>\n<p class=\"import-Normal\">Consider the La Brea Woman example from the section on asphalt above. The La Brea Woman\u2019s discovery was controversial, not because she is the only person to be found in the tar pits or because of her age but also because of necropolitics. The La Brea Woman was collected in 1914 and her body was housed on display at the George C. Page Museum in Los Angeles against the wishes of the Chumash and the Tongva, two tribes whose ancestral lands include Los Angeles. The museum decided to display a skull cast instead to meet the request of the tribes which included a separate postcranial skeleton from a different individual. The updated display itself was wrought with other ethical issues, as a cast of her skull was \u201cattached to the ancient remains of a Pakistani female that was dyed dark bronze, the femurs shortened to approximate the stature of native people\u201d (Cooper 2010). In both cases, neither the individuals or their descendent communities consented to the display or grotesque modification of human remains. According to an interview conducted by LA Weekly (Cooper 2010) with Cindi Alvitre, former chair of the Gabrielino-Tongva Tribal Council, the display of Indigenous human remains is akin to voyeurism. She states \u201cIt&#8217;s disheartening to me because it&#8217;s very inappropriate to display any human remains. The things we do to fill the imagination of visitors. It violates human rights.\u201d It is important to listen to the wishes of Indigenous people and center their values when conducting work with their ancestors. A good source for considering places to look for archaeological research ethics before conducting fieldwork (and ideally during your research design) is the Society for American Archaeology\u2019s ethics principle list, as well as following the Indigenous Archaeology Collective.<\/p>\n<p class=\"import-Normal\">Indigenous remains are now protected in the United States due to legislation such as Native American Graves Protection and Repatriation Act (NAGPRA). You can read more about this in Chapter 15: Bioarchaeology and Forensic Anthropology. Before the passing of NAGPRA, tribes had little agency over how the bodies of their ancestors were treated by anthropologists and museums, including decisions about sampling and destructive tests. Now when archaeological field work is conducted on federal land, tribes must be consulted before work begins. This consultation process often includes what to do if human remains are encountered. Indigenous tribes are multifaceted and multivocal; each has its own rules about how to handle the remains of their ancestors. In some cases, all work on the project must be halted after the discovery of human remains. Other tribes allow for work to continue if the remains are moved and reburied. Some tribes are open to radiometric dating if it aligns with their beliefs in the afterlife. Each tribe is different, and each tribe deserves to have its wishes respected.<\/p>\n<\/div>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Voices From the Past: What Fossils Can Tell Us<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Given that so few organisms ever become fossilized, any anthropologist or fossil hunter will tell you that finding a fossil is extremely exciting. But this is just the beginning of a fantastic mystery. With the creative application of scientific methods and deductive reasoning, a great deal can be learned about the fossilized organism and the environment in which it lived, leading to enhanced understanding of the world around us.<\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ccffcc;\"><strong>Dating Methods<\/strong><\/span><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Context is a crucial concept in paleoanthropology and archaeology. Objects and fossils are interesting in and of themselves, but without context there is only so much we can learn from them. One of the most important contextual pieces is the dating of an object or fossil. By being able to place it in time, we can compare it more accurately with other contemporary fossils and artifacts or we can better analyze the evolution of a fossil species or artifacts. To answer the question \u201cHow do we know what we know?,\u201d you have to know how archaeologists and paleoanthropologists establish dates for artifacts, fossils, and sites.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Though accurate dating is important for context and analysis, we must consider the impact. Many of the chronometric dating methods used by anthropologists require the removal of small samples from artifacts, bones, soils, and rock. Thus these techniques are considered destructive. How much of an artifact are you willing to destroy to get your date? Sharon Clough, a Senior Environmental Officer at Cotswold Archaeology, addressed this issue in a case study from her research. She stated that \u201cthe benefit of a date did not outweigh the destruction of a valuable and finite resource\u201d (Clough 2020). The resource in question was human remains. When considering our dating options, we want to be sure that we do as little harm as possible, especially in the case of human remains (read more about this issue in the Special Topic box, \u201cNecropolitics\u201d).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dating techniques are divided into two broad categories: relative dating methods and chronometric (sometimes called absolute) dating methods.<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ccffcc;\"><em>Relative Dating<\/em><\/span><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_876\">Relative dating<\/a><\/strong> methods are used first because they rely on simple observational skills. In the 1820s, Christian J\u00fcrgensen Thomsen at the National Museum of Denmark in Copenhagen developed the \u201cthree-age\u201d system still used in European archaeology today (Feder 2017, 17). He categorized the artifacts at the museum based on the idea that simpler tools and materials were most likely older than more complex tools and materials. Stone tools must predate metal tools because they do not require special technology to develop. Copper and bronze tools must predate iron because they can be smelted or worked at lower temperatures, etc. Based on these observations, he categorized the artifacts into Stone Age, Bronze Age, and Iron Age.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The restriction of relative dating is that you don\u2019t know specific dates or how much time passed between different sites or artifacts. You simply know that one artifact or fossil is older than another. Thomsen knew that Stone Age artifacts were older than Bronze Age artifacts, but he couldn\u2019t tell if they were hundreds of years older or thousands of years older. The same is true with fossils that have differences of ages into the hundreds of millions of years.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The first relative dating technique is <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_878\">stratigraphy<\/a> <\/strong>(Figure 7.20). You might have already heard this term if you have watched documentaries on archaeological excavations. That\u2019s because this method is still being used today. It provides a solid foundation for other dating techniques and gives important context to artifacts and fossils found at a site.<\/p>\n<figure style=\"width: 382px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image11-1.png\" alt=\"Stratigraphic cross-section with 12 strata.\" width=\"382\" height=\"662\" \/><figcaption class=\"wp-caption-text\">Figure 7.20: An illustration of a stratigraphic cross-section. The objects at a lower strata are older than the one above. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Stratigraphic cross-section (Figure 7.28)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">Stratigraphy is based on the <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_880\">Law of Superposition<\/a><\/strong> first proposed by Nicholas Steno in 1669 and further explored by James Hutton (the previously mentioned \u201cFather\u201d of Deep Time). Essentially, superposition tells us that things on the bottom are older than things on the top (Williams 2004, 28). Notice on Figure 7.20 that there are distinctive layers piled on top of each other. It stands to reason that each layer is older than the one immediately on top of it (Hester et al. 1997, 338). Think of a pile of laundry on the floor. Over the course of a week, as dirty clothes get tossed on that pile, the shirt tossed down on Monday will be at the bottom of the pile while the shirt tossed down on Friday will be at the top. Assuming that the laundry pile was undisturbed throughout the week, if the clothes were picked up layer by layer, the clothing choices that week could be reconstructed in the order that they were worn.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Another relative dating technique is <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_882\">biostratigraphy<\/a><\/strong>. This form of dating looks at the context of a fossil or artifact and compares it to the other fossils and biological remains (plant and animal) found in the same stratigraphic layers. For instance, if an artifact is found in the same layer as wooly mammoth remains, you know that it must date to around the last ice age, when wooly mammoths were still abundant on Earth. In the absence of more specific dating techniques, early archaeologists could prove the great antiquity of stone tools because of their association with extinct animals. The application of this relative dating technique in archaeology was used at the Folsom site in New Mexico. In 1927, a stone spear point was discovered embedded in the rib of an extinct species of bison. Because of the undeniable association between the artifact and the ancient animal, there was scientific evidence that people had occupied the North American continent since antiquity (Cook 1928).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Similar to biostratigraphic dating is <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_884\">cultural dating<\/a> <\/strong>(Figure 7.21). This relative dating technique is used to identify the chronological relationships between human-made artifacts. Cultural dating is based on artifact types and styles (Hester et al. 1997, 338). For instance, a pocket knife by itself is difficult to date. However, if the same pocket knife is discovered surrounded by cassette tapes and VHS tapes, it is logical to assume that the artifact came from the late 20th century like the cassette and VHS tapes. The pocket knife could not be dated earlier than the late 20th century because the tapes were made no earlier than 1977. In the Thomsen example above, he was able to identify a relative chronology of ancient European tools based on the artifact styles, manufacturing techniques, and raw materials. Cultural dating can be used with any human-made artifacts. Both cultural dating and biostratigraphy are most effective when researchers are already familiar with the time periods for the artifacts and animals. They are still used today to identify general time periods for sites.<\/p>\n<figure style=\"width: 364px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image26-1.png\" alt=\"Ax heads, swords, circlets, and pots by type.\" width=\"364\" height=\"557\" \/><figcaption class=\"wp-caption-text\">Figure 7.21: Charts of typology, like these representing items from the Bronze Age, are used to classify artifacts and illustrate cultural material assemblages. Credit: <a href=\"https:\/\/wellcomecollection.org\/works\/de5rxx5a\">Bronze Age implements, ornaments and pottery (Period II)<\/a> by <a href=\"https:\/\/wellcomecollection.org\/\">Wellcome Collection<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by\/4.0\/#_ga=2.5144115.1054155377.1564173886-467226638.1563307053\">CC BY 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Chemical dating was developed in the 19th century and represents one of the early attempts to use soil composition and chemistry to date artifacts. A specific type of chemical dating is <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_886\">fluorine dating<\/a><\/strong>, and it is commonly used to compare the age of the soil around bone, antler, and teeth located in close proximity (Cook and Ezra-Cohn 1959; Goodrum and Olson 2009). While this technique is based on chemical dating, it only provides the relative dates of items rather than their absolute ages. For this reason, fluorine dating is considered a hybrid form of relative and chronometric dating methods (which will be discussed next).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Soils contain different amounts of chemicals, and those chemicals, such as fluorine, can be absorbed by human and animal bones buried in the soil. The longer the remains are in the soil, the more fluorine they will absorb (Cook and Ezra-Cohn 1959; Goodrum and Olson 2009). A sample of the bone or antler can be processed and measured for its fluorine content. Unfortunately, this absorption rate is highly sensitive to temperature, soil pH, and varying fluorine levels in local soil and groundwater (Goodrum and Olson 2009; Haddy and Hanson 1982). This makes it difficult to get an accurate date for the remains or to compare remains between two sites. However, this technique is particularly useful for determining whether different artifacts come from the same burial context. If they were buried in the same soil for the same length of time, their fluorine signatures would match.<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ccffcc;\"><em>Chronometric Dating<\/em><\/span><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Unlike relative dating methods, <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_888\">chronometric dating<\/a><\/strong> methods provide specific dates and time ranges. Many of the chronometric techniques we will discuss are based on work in other disciplines such as chemistry and physics. The modern developments in studying radioactive materials are accurate and precise in establishing dates for ancient sites and remains.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Many of the chronometric dating methods are based on the measurement of radioactive decay of particular elements. <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_890\">Elements<\/a><\/strong> are materials that cannot be broken down into more simple materials without losing their chemical identity (Brown et al. 2018, 48). Each element consists of an <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_892\">atom<\/a><\/strong> that has a specific number of protons (positively charged particles) and electrons (negatively charged particles) as well as varying numbers of neutrons (particles with no charge). The protons and neutrons are located in the densely compacted nucleus of the atom, but the majority of the volume of an atom is space outside the nucleus around which the electrons orbit (see Figure 7.22).<\/p>\n<figure style=\"width: 285px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image18-1-1.png\" alt=\"Atom labeled with nucleus, proton, neutron, and electron.\" width=\"285\" height=\"285\" \/><figcaption class=\"wp-caption-text\">Figure 7.22: Simplified illustration of an atom. Credit: <a href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Atom%20Diagram.svg\">Atom Diagram<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:AG_Caesar\">AG Caesar<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/legalcode\">CC BY-SA 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Elements are classified based on the number of protons in the nucleus. For example, carbon has six protons, giving it an atomic number 6. Uranium has 92 protons, which means that it has an atomic number 92. While the number of protons in the atom of an element do not vary, the number of neutrons may. Atoms of a given element that have different numbers of neutrons are known as <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_894\">isotopes<\/a><\/strong>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The majority of an atom\u2019s mass is determined by the protons and neutrons, which have more than a thousand times the mass of an electron. Due to the different numbers of neutrons in the nucleus, isotopes vary by nuclear\/atomic weight (Brown et al. 2018, 94). For instance, isotopes of carbon include carbon 12 (<sup>12<\/sup>C), carbon 13 (<sup>13<\/sup>C), and carbon 14 (<sup>14<\/sup>C). Carbon always has six protons, but <sup>12<\/sup>C has six neutrons whereas <sup>14<\/sup>C has eight neutrons. Because <sup>14<\/sup>C has more neutrons, it has a greater mass than <sup>12<\/sup>C (Brown et al. 2018, 95).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Most isotopes in nature are considered <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_896\">stable isotopes<\/a><\/strong> and will remain in their normal structure indefinitely. However, some isotopes are considered <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_898\">unstable isotopes<\/a><\/strong> (sometimes called radioisotopes) because they spontaneously release energy and particles, transforming into stable isotopes (Brown et al. 2018, 946; Flowers et al. 2018, section 21.1). The process of transforming the atom by spontaneously releasing energy is called <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_900\">radioactive decay<\/a><\/strong>. This change occurs at a predictable rate for nearly all radioisotopes of elements, allowing scientists to use unstable isotopes to measure time passage from a few hundred to a few billion years with a large degree of accuracy and precision.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The leading chronometric method for archaeology is <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_902\">radiocarbon dating<\/a> <\/strong>(Figure 7.23). This method is based on the decay of <sup>14<\/sup>C, which is an unstable isotope of carbon. It is created when nitrogen 14 (<sup>14<\/sup>N) interacts with cosmic rays, which causes it to capture a neutron and convert to <sup>14<\/sup>C. Carbon 14 in our atmosphere is absorbed by plants during photosynthesis, a process by which light energy is turned into chemical energy to sustain life in plants, algae, and some bacteria. Plants absorb carbon dioxide from the atmosphere and use the energy from light to convert it into sugar that fuels the plant (Campbell and Reece 2005, 181\u2013200). Though <sup>14<\/sup>C is an unstable isotope, plants can use it in the same way that they use the stable isotopes of carbon.<\/p>\n<figure style=\"width: 514px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image27.png\" alt=\"Creation of Carbon 14.\" width=\"514\" height=\"658\" \/><figcaption class=\"wp-caption-text\">Figure 7.23: A graphic illustrating how 14C is created in the atmosphere, is absorbed by living organisms, and ends up in the archaeological record. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Radiocarbon dating (Figure 7.32)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">Animals get <sup>14<\/sup>C by eating the plants. Humans take it in by eating plants and animals. After death, organisms stop taking in new carbon, and the unstable <sup>14<\/sup>C will begin to decay. Carbon 14 has a half-life of 5,730 years (Hester et al. 1997, 324). That means that in 5,730 years, half the amount of <sup>14<\/sup>C will convert back into <sup>14<\/sup>N. Because the pattern of radioactive decay is so reliable, we can use <sup>14<\/sup>C to accurately date sites up to 55,000 years old (Hajdas et al. 2021). However, <sup>14<\/sup>C can only be used on the remains of biological organisms. This includes charcoal, shell, wood, plant material, and bone. This method involves destroying a small sample of the material. Earlier methods of radiocarbon dating required at least 1 gram of material, but with the introduction of accelerator mass spectrometry (AMS), sample sizes as small as 1 milligram can now be used (Hajdas et al. 2021). This significantly reduces the destructive nature of this method.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The use of radiocarbon dating at Denisova Cave in modern-day Russia revealed an astounding find, the first dated first-generation individual with a Neanderthal mother and Denisovan father. Vivian Slon and colleagues (2018) sequenced the genome, which revealed the individual&#8217;s hybrid genetic background, and radiocarbon dated the remains, revealing the sub-adult was over 50,000 years old (Slon et al. 2018).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As mentioned before, <sup>14<\/sup>C is unstable and ultimately decays back into <sup>14<\/sup>N. This decay is happening at a constant rate (even now, inside your own body!). However, as long as an organism is alive and taking in food, <sup>14<\/sup>C is being replenished in the body. As soon as an organism dies, it no longer takes in new <sup>14<\/sup>C. We can then use the rate of decay to measure how long it has been since the organism died (Hester et al. 1997, 324). However, the amount of <sup>14<\/sup>C in the atmosphere is not stable over time. It fluctuates based on changes to the earth\u2019s magnetic field and solar activity. In order to turn <sup>14<\/sup>C results into accurate calendar years, they must be calibrated using data from other sources. Annual tree rings (see discussion of <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_904\">dendrochronology<\/a><\/strong> below), <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_906\">foraminifera<\/a><\/strong> from stratified marine sediments, and microfossils from lake sediments can be used to chart the changes in <sup>14<\/sup>C as \u201ccalibration curves.\u201d The radiocarbon date obtained from the sample is compared to the established curve and then adjusted to reflect a more accurate calendar date (see Figure 7.24). The curves are updated over time with more data so that we can continue to refine radiocarbon dates (T\u00f6rnqvist et al. 2016). The most recent calibration curves were released in 2020 and may change the dates for some existing sites by hundreds of years (Jones 2020).<\/p>\n<figure style=\"width: 547px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image17-2.jpg\" alt=\"Radiocarbon date calibration curve.\" width=\"547\" height=\"384\" \/><figcaption class=\"wp-caption-text\">Figure 7.24: This is a simplified example of a calibration curve, showing how the radiocarbon age (y axis) is compared with the calibration curve to produce calibrated dates (x axis). <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 href=\"https:\/\/commons.wikimedia.org\/wiki\/File:Radiocarbon_Date_Calibration_Curve.svg\">Radiocarbon Date Calibration Curve<\/a> by <a href=\"https:\/\/commons.wikimedia.org\/wiki\/User:HowardMorland\">HowardMorland<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-sa\/3.0\/\">CC BY-SA 3.0 License<\/a>. [Based on information from Reimer et al. 2004. Radiocarbon 46: 1029-58.]<\/figcaption><\/figure>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As you will see in the hominin chapters (Chapters 9\u201312), 55,000 years is only a tiny fragment of human evolutionary history. It is insignificant in the context of the age of our planet. In order to date even older fossils, other methods are necessary.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_908\">Potassium-argon (K-Ar) dating<\/a><\/strong> and <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_910\">argon-argon (Ar-Ar) dating<\/a><\/strong> can reach further back into the past than radiocarbon dating. Used to date volcanic rock, these techniques are based on the decay of unstable potassium 40 (<sup>40<\/sup>K) into argon 40 (<sup>40<\/sup>Ar) gas, which gets trapped in the crystalline structures of volcanic material. It is a method of indirect dating. Instead of dating the fossil itself, K-Ar and Ar-Ar dates volcanic layers around the fossil. It will tell you when the volcanic eruption that deposited the layers occurred. This is where stratigraphy becomes important. The date of the surrounding layers can give you a minimum and maximum age of the fossil based on where it is in relation to those layers. This technique was used at Gesher Benot Ya&#8217;aqo in the Jordan Valley, dating early stratigraphic deposits of basalt flows to 100,000 years old (Bar-Yosef and Belmaker 2011). The site is unique because early layers of occupation with an Acheulean handaxe industry were made primarily of basalt, which is an uncommon material for this tool technology (see Chapter 10 for a full discussion of this tool technology). The benefit of this dating technique is that <sup>40<\/sup>K has a half-life of circa 1.3 billion years, so it can be used on sites as young as 100 kya and as old as the age of Earth. As you will see in later chapters, it is particularly useful in dating early hominin sites in Africa (Michels 1972, 120; Renfrew and Bahn 2016, 155). Another benefit to this technique is that it does not damage precious fossils because the samples are taken from the surrounding rock instead. However, this method is not without its flaws. A study by J. G. Funkhouser and colleagues (1966) and Raymond Bradley (2015) demonstrated that igneous rocks with fluid inclusions, such as those found in Hawai\u2018i, can release gasses including radiogenic argon when crushed, leading to incorrectly older dates. This is an example of why it is important to use multiple dating methods in research to detect anomalies.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_912\">Uranium series dating<\/a><\/strong> is based on the decay chain of unstable isotopes of uranium. It uses mass spectrometry to detect the ratios of uranium 238 (<sup>238<\/sup>U), uranium 234(<sup>234<\/sup>U), and thorium 230 (<sup>230<\/sup>Th) in carbonates (Wendt et al. 2021). Thorium accumulates in the carbonate sample through radiometric decay. Thus, the age of the sample is calculated from the difference between a known initial ratio and the ratio present in the sample to be dated. This makes uranium series ideal for dating carbonate rich deposits such as carbonate cements from glacial moraine deposits, speleothems (deposits of secondary minerals that form on the walls, floors, and ceilings of caves, like stalactites and stalagmites), marine and lacustrine carbonates from corals, caliche, and tufa, as well as bones and teeth (University of Arizona, n.d.; van Calsteren and Thomas 2006). Due to the timing of the decay process, this dating technique can be used from a few years up to 650k (Wendt et al. 2021). Since many early hominin sites occur in cave environments, this dating technique can be very powerful. This method has also been used to develop more accurate calibration curves for radiocarbon dating. However, the accuracy of this method depends on knowing the initial ratios of the elements and ruling out possible contamination (Wendt et al. 2021). It also involves the destruction of a small sample of material.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_914\">Fission track dating<\/a> <\/strong>is another useful dating technique for sites that are millions of years old. This is based on the decay of radioactive uranium 238 (<sup>238<\/sup>U). The unstable atom of <sup>238<\/sup>U fissions at a predictable rate. The fission takes a lot of energy and causes damage to the surrounding rock. For instance, in volcanic glasses we can see this damage as trails in the glass. Researchers in the lab take a sample of the glass and count the number of fission trails using an optical microscope. As <sup>238<\/sup>U has a half-life of 4,500 million years, it can be used to date rock and mineral material starting at just a few decades and extending back to the age of Earth. As with K-Ar, archaeologists are not dating artifacts directly. They are dating the layers around the artifacts in which they are interested (Laurenzi et al. 2007).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_916\">Luminescence dating<\/a><\/strong>, which includes thermoluminescence and a related technique called optically stimulated luminescence, is based on the naturally occurring background radiation in soils. Pottery, baked clay, and sediments that include quartz and feldspar are bombarded by radiation from the soils surrounding it. Electrons in the material get displaced from their orbit and trapped in the crystalline structure of the pottery, rock, or sediment. When a sample of the material is heated to 500\u00b0C (thermoluminescence) or exposed to particular light wavelengths (optically stimulated luminescence) in the laboratory, this energy gets released in the form of light and heat and can be measured (Cochrane et al. 2013; Renfrew and Bahn 2016, 160). You can use this method to date artifacts like pottery and burnt flint directly. When attempting to date fossils, you may use this method on the crystalline grains of quartz and feldspar in the surrounding soils (Cochrane et al. 2013). The important thing to remember with this form of dating is that heating the artifact or soils will reset the clock. The method is not necessarily dating when the object was last made or used but when it was last heated to 500\u00b0C or more (pottery) or exposed to sunlight (sediments). Luminescence dating can be used on sites from less than 100 years to over 100,000 years (Duller 2008, 4). As with all archaeological data, context is crucial to understanding the information.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Like thermoluminescence dating, <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_918\">electron spin resonance dating<\/a><\/strong> is based on the measurement of accumulated background radiation from the burial environment. It is used on artifacts and rocks with crystalline structures, including tooth enamel, shell, and rock\u2014those for which thermoluminescence would not work. The radiation causes electrons to become dislodged from their normal orbit. They become trapped in the crystalline matrix and affect the electromagnetic energy of the object. This energy can be measured and used to estimate the length of time in the burial environment. This technique works well for remains as old as two million years (Carvajal et al. 2011, 115\u2013116). It has the added benefit of being nondestructive, which is an important consideration when dealing with irreplaceable material.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Not all chronometric dating methods are based on unstable isotopes and their rates of decay. There are several other methods that make use of other natural biological and geologic processes. One such method is known as dendrochronology (Figure 7.25), which is based on the natural growth patterns of trees. Trees create concentric rings as they grow; the width of those rings depends on environmental conditions and season. The age of a tree can be determined by counting its rings, which also show records of rainfall, droughts, and forest fires.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image16-1.png\" alt=\"A tree, cross-section of tree core, and tree-ring timeline.\" width=\"413\" height=\"450\" \/><\/p>\n<figure style=\"width: 411px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image23-1-1.png\" alt=\"Tree rings and dates.\" width=\"411\" height=\"424\" \/><figcaption class=\"wp-caption-text\">Figure 7.25: Dendrochronology uses the variations in tree rings to create timelines. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Dendrochronology (Figure 7.34)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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;\">Tree rings can be used to date wood artifacts and ecofacts from archaeological sites. This first requires the creation of a profile of trees in a particular area. The Laboratory of Tree-Ring Research at the University of Arizona has a comprehensive and ongoing catalog of tree profiles (see University of Arizona n.d.). Archaeologists can then compare wood artifacts and ecofacts with existing timelines, provided the tree rings are visible, and find where their artifacts fit in the pattern. Dendrochronology has been in use since the early 20th century (Dean 2009, 25). The Northern Hemisphere chronology stretches back nearly 14,000 years (Reimer et al. 2013, 1870) and has been used successfully to date southwestern U.S. sites such as Pueblo Bonito and Aztec Ruin (Dean 2009, 26). Dendrochronological evidence has helped calibrate radiocarbon dates and even provided direct evidence of global warming (Dean 2009, 26\u201327).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">In Australia, dendrochronology, along with other environmental reconstruction methods, has been used to show that the Indigenous people had sophisticated land management systems before the arrival of British invaders. According to the work of Michael-Shawn Fletcher and colleagues (2021), there was a significant encroachment of the rainforests and tree species into grasslands after the British invasion. Prior to this time, Indigenous people managed the landscape through controlled burns at regular intervals. This practice created climate-resistant grasslands that were biodiverse and provided predictable food supplies for humans and other animals. Under European land management, there have been negative impacts on biodiversity and climate resilience and an increase in catastrophic wildfires (Fletcher et al. 2021).<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">This dating method does have its difficulties. Some issues are interrupted ring growth, microclimates, and species growth variations. This is addressed through using multiple samples, statistical analysis, and calibration with other dating methods. Despite these limitations, dendrochronology can be a powerful tool in dating archaeological sites (Hillam et al. 1990; Kuniholm and Striker 1987).<\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Environmental Reconstruction<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">As you read in Chapter 2, Charles Darwin, Jean-Baptiste Lamarck, Alfred Russel Wallace, and others recognized the importance of the environment in shaping the evolutionary course of animal species. To understand what selective processes might be shaping evolutionary change, we must be able to reconstruct the environment in which the organism was living.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">One of the ways to do that is to look at the plant species that lived in the same time range as the species in which you are interested. One way to identify ancient flora is to analyze <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_920\">sediment cores<\/a><\/strong> from water and other protected sources. Pollen gets released into the air and some of that pollen will fall on wetlands, lakes, caves, and so forth. Eventually it sinks to the bottom of the lake and forms part of the sediment. This happens year after year, so subsequent layers of pollen build up in an area, creating strata. By taking a core sample and analyzing the pollen and other organic material, an archaeologist can build a timeline of plant types and see changes in the vegetation of the area (Hester et al. 1997, 284). This can even be done over large areas by studying ocean bed cores, which accumulate pollen and dust from large swaths of neighboring continents.<\/p>\n<p class=\"import-Normal\">While sediment coring is one of the more common ways to reconstruct past environments, there are a few other methods. These have been recently employed at Holocene Lake Ivanpah, a paleolake that straddles the California and Nevada border in the United States. This lake was originally thought to have been completely dry around 9,300\u20137,800 kya (Sims and Spaulding 2017). However, analyzing core samples using soil identification, sediment chemistry, subsurface stratigraphy, and <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_922\">geomorphology<\/a><\/strong> (the study of the physical characteristics of the Earth\u2019s surface) revealed deposition of three recent lake fillings during this period in the forms of additional hardpan, or lake bottom, playas, bedded or layered fine-grained (wetland) sediments, and buried beaches below the surface (Sims and Spaulding 2017; Spaulding and Sims 2018). These discoveries are important because they have not been integrated into interpretation of the local archaeological record, as it was assumed that the lake had been dry for thousands of years. Sedimentological analyses such as coring and those listed above can provide great insight into past climates and are accomplished in a minimally destructive way.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Another way of reconstructing past environments is by using stable isotopes. Unlike unstable isotopes, stable isotopes remain constant in the environment throughout time. Plants take in the isotopes through photosynthesis and ground water absorption. Animals take in isotopes by drinking local water and eating plants. Stable isotopes can be powerful tools for identifying where an organism grew up and what kind of food the organism ate throughout its life. They can even be used to identify global temperature fluctuations.<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Global Temperature Reconstruction<\/em><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Oxygen isotopes are a powerful tool in tracking global temperature fluctuations throughout time. The isotopes of Oxygen 18 (<sup>18<\/sup>O) and Oxygen 16 (<sup>16<\/sup>O) occur naturally in Earth\u2019s water. Both are stable isotopes, but <sup>18<\/sup>O has a heavier atomic weight. In the normal water cycle, evaporation takes water molecules from the surface to the atmosphere. Because <sup>16<\/sup>O is lighter, it is more likely to be part of this evaporation process. The moisture gathers in the atmosphere as clouds that eventually may produce rain or snow and release the water back to the surface of the planet. During cool periods like <strong><a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_924\">glacial periods<\/a><\/strong> (ice ages), the evaporated water often comes down to Earth\u2019s surface as snow. The snow piles up in the winter but, because of the cooler summers, does not melt off. Instead, it gets compacted and layered year after year, eventually resulting in large glaciers or ice sheets covering parts of Earth. Since <sup>16<\/sup>O, with the lighter atomic weight, is more likely to be absorbed in the evaporation process, it gets locked up in glacier formation. The waters left in oceans would have a higher ratio of <sup>18<\/sup>O during these periods of cooler global temperatures (Potts 2012, 154\u2013156; see Figure 7.26).<\/p>\n<figure style=\"width: 389px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image15-1.png\" alt=\"Graph with oxygen isotope on y axis and years on x axis.\" width=\"389\" height=\"218\" \/><figcaption class=\"wp-caption-text\">Figure 7.26: This graph depicts how temperatures of the sea have fluctuated greatly over the course of the history of the planet. <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 href=\"https:\/\/www.giss.nasa.gov\/research\/briefs\/1999_schmidt_01\/\">Oxygen in deep sea sediment carbonate (Figure 2)<\/a> by <a href=\"https:\/\/www.giss.nasa.gov\/\">NASA Goddard Institute for Space Studies<\/a> originally from &#8220;Science Briefs: Cold Climates, Warm Climates: How Can We Tell Past Temperatures?&#8221; by <a href=\"https:\/\/www.giss.nasa.gov\/staff\/gschmidt.html\">Gavin Schmidt<\/a>, is in the <a 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 microorganisms that live in the oceans, foraminifera, absorb the water from their environment and use the oxygen isotopes in their body structures. When these organisms die, they sink to the ocean floor, contributing to the layers of sediment. Scientists can extract these ocean cores and sample the remains of foraminifera for their <sup>18<\/sup>O and <sup>16<\/sup>O ratios. These ratios give us a good approximation of global temperatures deep into the past. Cooler temperatures indicate higher ratios of <sup>18<\/sup>O (Potts 2012, 154\u2013156).<\/p>\n<h4 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><em>Diet Reconstruction<\/em><\/h4>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">You may be familiar with the saying \u201cyou are what you eat.\u201d When it comes to your teeth and bones, this adage is literal. Stable isotopes can also be used to reconstruct animal diet and migration patterns. Living organisms absorb elements from ingested plants and water. These elements are used in tissues like bones, teeth, skin, hair, and so on. By analyzing the stable isotopes in the bones and teeth of humans and other animals, we can identify the types of food they ate at different stages of their lives.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Plants take in carbon dioxide from the atmosphere during photosynthesis. We\u2019ve already discussed this using the example of the unstable isotope <sup>14<\/sup>C; however, this absorption also takes place with the stable isotopes of <sup>12<\/sup>C and <sup>13<\/sup>C. During photosynthesis, some plants incorporate carbon dioxide as a three-carbon molecule (C3 plants) and some as a four-carbon molecule (C4 plants). On the one hand, C3 plants include certain types of trees and shrubs that are found in relatively wet environments and have lower ratios of <sup>13<\/sup>C compared to <sup>12<\/sup>C. C4 plants, on the other hand, include plants from drier environments like savannahs and grasslands. C4 plants have higher ratios of <sup>13<\/sup>C to <sup>12<\/sup>C than C3 plants (Renfrew and Bahn 2016, 312). These ratios remain stable as you go up the food chain. Therefore, you can analyze the bones and teeth of an animal to identify the <sup>13<\/sup>C\/<sup>12<\/sup>C ratios and identify the types of plants that animal was eating.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">The ratios of stable nitrogen isotopes <sup>15<\/sup>N and <sup>14<\/sup>N can also give information about the diet of fossilized or deceased organisms. Though initially absorbed from water and soils by plants, the nitrogen ratios change depending on the primary diet of the organism. An animal who has a mostly vegetarian diet will have lower ratios of <sup>15<\/sup>N to <sup>14<\/sup>N, while those further up the food chain, like carnivores, will have higher ratios of <sup>15<\/sup>N. Interestingly, breastfeeding infants have a higher nitrogen ratio than their mothers, because they are getting all of their nutrients through their mother\u2019s milk. So nitrogen can be used to track life events like weaning (Jay et al. 2008, 2). A marine versus terrestrial diet will also affect the nitrogen signatures. Terrestrial diets have lower ratios of <sup>15<\/sup>N than marine diets. In the course of human evolution, this type of analysis can help us identify important changes in human nutrition. It can help anthropologists figure out when meat became a primary part of the ancient human diet or when marine resources began to be used. The ratios of stable nitrogen isotopes can also be used to determine a change in status, as in the case of the Llullaillaco children (the \u201cice mummies\u201d) found in the Andes Mountains. For instance, the nitrogen values in hair from the Llullaillaco Maiden showed a significant positive shift that is associated with increased meat consumption in the last 12 months of her life (Wilson et al. 2007). Although the two younger children had little changes in their diets in the last year of their short lives, the changes in their nitrogen values were significant enough to suggest that the improvement in their diets may have been attributed to the Incas\u2019 desire to sacrifice healthy, high-status children\u201d (Faux 2012, 6).<\/p>\n<h4 class=\"import-Normal\"><em>Migration<\/em><\/h4>\n<p class=\"import-Normal\">Stable isotopes can also tell us a great deal about where an individual lived and whether they migrated during their lifetime. The geology of Earth varies because rocks and soils have different amounts or ratios of certain elements in them. These variations in the ratios of isotopes of certain elements are called isotopic signatures. They are like a chemical fingerprint for a geographical region. These isotopes get into the groundwater and are absorbed by plants and animals living in that area. Elements like strontium, oxygen, and nitrogen, among others, are then used by the body to build bones and teeth. If you ate and drank local water all of your life, your bones and teeth would have the same isotopic signature as the geographical region in which you lived.<\/p>\n<p class=\"import-Normal\">However, many people (and animals) move around during their lifetimes. Isotopic signatures can be used to identify migration patterns in organisms (Montgomery et al. 2005). Teeth develop in early childhood. If the isotopes of teeth are analyzed, these isotopes would resemble those found in the geographic area where an individual lived as a child. Bones, however, are a different story. Bones are constantly changing throughout life. Old cells are removed and new cells are deposited to respond to growth, healing, activity change, and general deterioration. Therefore, the isotopic signature of bones will reflect the geographical area in which an individual spent the last seven to ten years of life. If an individual has different isotopic signatures for their bones and teeth, it could indicate a migration some time during their life after childhood.<\/p>\n<figure style=\"width: 386px\" class=\"wp-caption alignright\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image24-2.jpg\" alt=\"Upright boulders of Stonehenge.\" width=\"386\" height=\"289\" \/><figcaption class=\"wp-caption-text\">Figure 7.27: Stonehenge continues to provide clues to its mysterious existence with recent research using isotope ratios. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Stonehenge (Figure 7.37)<\/a> by Sarah S. King is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p>Recent work involving stable isotope analysis has been done on the cremation burials from Stonehenge, in Wessex, England (Figure 7.27). Much of the archaeological work at Stonehenge in the past focused on the building and development of the monument itself. That is partly because most of the burials at the monument were cremated remains, which are difficult to study because of their fragmentary nature and the chemical alterations that bone and teeth undergo when heated. The cremation process complicates the oxygen and carbon isotopes. However, the researchers determined that strontium would not be affected by heating and could still be analyzed in cranial fragments. Using the remains of 25 individuals, they compared their strontium signatures to the geology of Wessex and other regions of the UK. Fifteen of those individuals had strontium signatures that matched the local geology. This means that in the last ten or so years of their lives, they lived and ate food from around Stonehenge. However, ten of the individuals did not match the local geologic signature. These individuals had strontium ratios more closely aligned with the geology of west Wales. Archaeologists find this particularly interesting because in the early phases of Stonehenge\u2019s construction, the smaller \u201cblue stones\u201d were brought 200 km from Wales in a feat of early engineering. These larger regional connections show that Stonehenge was not just a site of local importance. It dominated a much larger region of influence and drew people from all over ancient Britain (Snoeck et al. 2018).<\/p>\n<div class=\"textbox\">\n<h2 class=\"import-Normal\">Special Topic: Cold Case Naia<\/h2>\n<figure style=\"width: 455px\" class=\"wp-caption alignleft\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image4-1-2.png\" alt=\"Sites on Yucatan peninsula.\" width=\"455\" height=\"351\" \/><figcaption class=\"wp-caption-text\">Figure 7.28: Map of Mexico showing the Yucatan Peninsula and the locations of Hoyo Negro and Sistema Sac Actun. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Hoyo Negro and Sistema Sac Actun, Mexic0 (Figure 7.38)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Elyssa Ebding at <a href=\"https:\/\/www.csuchico.edu\/geop\/geoplace\/index.shtml\">GeoPlace, California State University, Chico<\/a> is under a <a href=\"https:\/\/creativecommons.org\/licenses\/by-nc\/4.0\/\">CC BY-NC 4.0 License<\/a>.<\/figcaption><\/figure>\n<p class=\"import-Normal\">In 2007, cave divers exploring the Sistema Sac Actun in the Yucat\u00e1n Peninsula in Mexico (see Figure 7.28 and 7.29) discovered the bones of a 15- to 16-year-old female human along with the bones of various extinct animals from the Pleistocene (Collins et al. 2015). The site was named Hoyo Negro (\u201cBlack Hole\u201d). The human bones belonged to a Paleo-American, later named \u201cNaia\u201d after a Greek water nymph. Examination of the partially fossilized remains revealed a great deal about Naia\u2019s life, and the radiocarbon dating of her tooth enamel indicated that she lived some 13,000 years ago (Chatters et al. 2014). Naia\u2019s arms were not overly developed, so her daily activities did not involve heavy carrying or grinding of grain or seeds. Her legs, however, were quite muscular, implying that Naia was used to walking long distances. Naia\u2019s teeth and bones indicate habitually poor nutrition. There is evidence of violent injury during the course of Naia\u2019s life from a healed spiral fracture of her left forearm. Naia also suffered from tooth decay and osteoporosis even though she appeared young and undersized. Dr. Jim Chatters hypothesizes that Naia entered the cave at a time when it was not flooded, probably looking for water. She may have become disoriented and fell off a high ledge to her death. The trauma to her pelvis is consistent with such an injury (Watson 2017).<\/p>\n<p class=\"import-Normal\">Naia\u2019s skeleton is remarkably complete given its age. As divers were able to locate her skull, Naia\u2019s physical appearance in life could be interpreted. Surprisingly, in examining the skull, it was determined that Naia did not resemble modern Indigenous peoples in the region. However, the<strong> <a class=\"glossary-term\" aria-haspopup=\"dialog\" aria-describedby=\"definition\" href=\"#term_254_926\">mitochondrial DNA<\/a><\/strong> (mtDNA) recovered from a tooth indicates that Naia shares her DNA with modern Indigenous peoples (Chatters et al. 2014). Though Naia\u2019s burial environment made chemical analysis difficult, researchers were able to recover carbon isotopes from her remains. The isotopes from Naia\u2019s tooth enamel suggest a diet of \u201ccool-season grasses and\/or broad-leaf vegetation\u201d (Chatters et al. 2022, 68). Naia\u2019s teeth also displayed numerous dental caries and only light dental wear. Coupled with the isotopic data, she likely had a \u201csofter, more sugar-rich diet\u201d (Chatters et al. 2022, 68).<\/p>\n<figure style=\"width: 625px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image32-1.png\" alt=\"Cross-section of the Hoyo Negro cenote.\" width=\"625\" height=\"353\" \/><figcaption class=\"wp-caption-text\">Figure 7.29: A diagram of the Sistema Sac Actun and the Hoyo Negro cenote where Naia rested underwater for roughly 13,000 years. The illustration depicts a cenote or hole in the ground leading to a long, narrow tunnel, ending in a large cavern. The cavern and tunnel are both filled with water. Credit: <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/chapter\/__unknown__-7\/\">Hoyo Negro cenote (Figure 7.39)<\/a> original to <a href=\"https:\/\/pressbooks-dev.oer.hawaii.edu\/explorationsbioanth\/\">Explorations: An Open Invitation to Biological Anthropology<\/a> by Mary Nelson is under a <a 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\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ff99cc;\">Summary<\/span><\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><span style=\"background-color: #ff99cc;\">With a timeline that extends back some 4.6 billion years, Earth has witnessed continental drift, environmental changes, and a growing complexity of life. Fossils, the mineralized remains of living organisms, provide physical evidence of life and the environment on the planet over the course of billions of years. In order to better understand the fossil record, anthropologists rely on the collaboration of numerous academic fields and disciplines. Anthropologists use a variety of scientific methods, both relative and chronometric, to analyze fossils to determine age, origins, and migration patterns as well as to provide insight into the health and diet of the fossilized organism. While each method has its advantages, disadvantages, and limited applications, these tools enable anthropologists to theorize how all living organisms evolved, including the evolution of early humans into modern humans, <em>H. sapiens<\/em>. The fossil record is far from complete, but our expanding understanding of the fossil context, with exciting new discoveries and improved scientific methods, enables us to document the history of our planet and the evolution of life on Earth.<\/span><\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Dating Methods Quick Guide<\/strong><\/h3>\n<div style=\"text-align: left;\">\n<table style=\"width: 463.5pt; height: 586px;\">\n<thead>\n<tr style=\"height: 24.25pt;\">\n<td class=\"Table1-C\" style=\"padding: 5pt; border: 1pt solid #000000; height: 30px; width: 157.45px;\">\n<p class=\"import-Normal\"><strong>Method<\/strong><\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 1pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\n<p class=\"import-Normal\"><strong>Material <\/strong><\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 1pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\n<p class=\"import-Normal\"><strong>Effective date range<\/strong><\/p>\n<\/td>\n<\/tr>\n<\/thead>\n<tbody>\n<tr class=\"Table1-R\" style=\"height: 24.25pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 30px; width: 157.45px;\">\n<p class=\"import-Normal\">Stratigraphy<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\n<p class=\"import-Normal\">Soil layers<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\n<p class=\"import-Normal\">Relative<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 36px; width: 157.45px;\">\n<p class=\"import-Normal\">Biostratigraphy<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 36px; width: 250.533px;\">\n<p class=\"import-Normal\">Plant and animal remains<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 36px; width: 166.017px;\">\n<p class=\"import-Normal\">Relative<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 24.25pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 30px; width: 157.45px;\">\n<p class=\"import-Normal\">Cultural dating<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\n<p class=\"import-Normal\">Human-made objects<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\n<p class=\"import-Normal\">Relative<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 24.25pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 30px; width: 157.45px;\">\n<p class=\"import-Normal\">Fluorine<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 250.533px;\">\n<p class=\"import-Normal\">Bone, antler, teeth<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 30px; width: 166.017px;\">\n<p class=\"import-Normal\">Relative<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 78.25pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 90px; width: 157.45px;\">\n<p class=\"import-Normal\">Radiocarbon<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 90px; width: 250.533px;\">\n<p class=\"import-Normal\">Organic carbon bearing material (bones, teeth, antler, plant material, shell, charcoal)<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 90px; width: 166.017px;\">\n<p class=\"import-Normal\">Younger than 55,000 years<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 46px; width: 157.45px;\">\n<p class=\"import-Normal\">Potassium-argon and argon-argon<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 250.533px;\">\n<p class=\"import-Normal\">Volcanic rock<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 166.017px;\">\n<p class=\"import-Normal\">Older than 100,000 years<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 64.75pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 72px; width: 157.45px;\">\n<p class=\"import-Normal\">Uranium series<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 72px; width: 250.533px;\">\n<p class=\"import-Normal\">Carbonates such as stalactites, stalagmites, corals, caliche, and tufa<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 72px; width: 166.017px;\">\n<p class=\"import-Normal\">Younger than 650,000 years<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 46px; width: 157.45px;\">\n<p class=\"import-Normal\">Fission track<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 250.533px;\">\n<p class=\"import-Normal\">Volcanic glasses and crystalline minerals<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 166.017px;\">\n<p class=\"import-Normal\">Spans age of Earth<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 37.75pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 46px; width: 157.45px;\">\n<p class=\"import-Normal\">Luminescence<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 250.533px;\">\n<p class=\"import-Normal\">Pottery, baked clay, sediments<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 46px; width: 166.017px;\">\n<p class=\"import-Normal\">100 to older than 100,000 years<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 51.25pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 54px; width: 157.45px;\">\n<p class=\"import-Normal\">Electron spin resonance dating<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 54px; width: 250.533px;\">\n<p class=\"import-Normal\">Tooth enamel, shell, rock with crystalline structures<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 54px; width: 166.017px;\">\n<p class=\"import-Normal\">Younger than 2 million years<\/p>\n<\/td>\n<\/tr>\n<tr class=\"Table1-R\" style=\"height: 51.25pt;\">\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt; padding: 5pt; height: 61px; width: 157.45px;\">\n<p class=\"import-Normal\">Dendrochronology<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 61px; width: 250.533px;\">\n<p class=\"import-Normal\">Wood (where tree rings are identifiable)<\/p>\n<\/td>\n<td class=\"Table1-C\" style=\"border-color: #000000; border-style: solid; border-width: 0.75pt 1pt 1pt 0.75pt; padding: 5pt; height: 61px; width: 166.017px;\">\n<p class=\"import-Normal\">Dependent on location and available chronologies<\/p>\n<\/td>\n<\/tr>\n<tr style=\"height: 15px;\">\n<td style=\"height: 15px; width: 158.317px;\"><\/td>\n<td style=\"height: 15px; width: 251.9px;\"><\/td>\n<td style=\"height: 15px; width: 166.883px;\"><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<div class=\"textbox shaded\">\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Review Questions<\/h2>\n<ul>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">How do remains become fossils? What conditions are necessary for the fossilization process?<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">What kind of information could you acquire from a single fossil? What could it tell you about the broader environment?<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">What factors would you take into consideration when deciding which dating method to use for a particular artifact?<\/li>\n<li class=\"import-Normal\" style=\"text-indent: 0pt;\">What methods do anthropologists use to reconstruct past environments and lifestyles?<\/li>\n<\/ul>\n<\/div>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Key Terms<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Anaerobic<\/strong>: An oxygen-free environment.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Anthropocene<\/strong>: The proposed name for our current geologic epoch based on human-driven climate change.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Argon-argon (Ar-Ar) dating<\/strong>: A chronometric dating method that measures the ratio of argon gas in volcanic rock to estimate time elapsed since the volcanic rock cooled and solidified. See also <em>potassium-argon dating<\/em>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Atom<\/strong>: A small building block of matter.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Bezoars<\/strong>: Hard, concrete-like substances found in the intestines of fossil creatures.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Biostratigraphy<\/strong>: A relative dating method that uses other plant and animal remains occurring in the stratigraphic context to establish time depth.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Bya<\/strong>: Billion years ago.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Chronometric dating<\/strong>: Dating methods that give estimated numbers of years for artifacts and sites.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Continental drift<\/strong>: The slow movement of continents over time.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Coprolite<\/strong>: Fossilized poop.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Cultural dating<\/strong>: The relative dating method that arranges human-made artifacts in a time frame from oldest to youngest based on material, production technique, style, and other features.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Deep Time<\/strong>: James Hutton\u2019s theory that the world was much older than biblical explanations allowed. This age could be determined by gradual natural processes like soil erosion.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Dendrochronology<\/strong>: A chronometric dating method that uses the annual growth of trees to build a timeline into the past.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Electron spin resonance dating<\/strong>: A chronometric dating method that measures the background radiation accumulated in material over time.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Element<\/strong>: Matter that cannot be broken down into smaller matter.<\/p>\n<p class=\"import-Normal\"><strong>Eon<\/strong>: The largest unit of geologic time, spanning billions of years and divided into subunits called <em>eras<\/em>, <em>periods<\/em>, and <em>epochs<\/em>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Epochs<\/strong>: The smallest units of geologic time, spanning thousands to millions of years.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Eras<\/strong>: Units of geologic time that span millions to billions of years and that are subdivided into <em>periods<\/em> and <em>epochs<\/em>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Fission track dating<\/strong>: A chronometric dating method that is based on the fission of <sup>283<\/sup>U.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Fluorine dating<\/strong>: A relative dating method that analyzes the absorption of fluorine in bones from the surrounding soils.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Foraminifera<\/strong>: Single-celled marine organisms with shells.<\/p>\n<p class=\"import-Normal\"><strong>Fossilization<\/strong>: The process by which an organism becomes a fossil.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Fossils<\/strong>: Mineralized copies of organisms or activity imprints.<\/p>\n<p class=\"import-Normal\"><strong>G<\/strong><strong>eomorphology<\/strong>: The study of the physical characteristics of the Earth\u2019s surface.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Glacial periods<\/strong>: Periods characterized by low global temperatures and the expansion of ice sheets on Earth\u2019s surface.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Holocene<\/strong>: The geologic epoch from 10 kya to present. (See the discussion on \u201cthe Anthropocene\u201d for the debate regarding the current epoch name.)<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Hominin<\/strong>: The term used for humans and their ancestors after the split with chimpanzees and bonobos.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>In matrix<\/strong>: When a fossil is embedded in a substance, such as igneous rock.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Isotopes<\/strong>: Variants of elements.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Kya<\/strong>: Thousand years ago.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Law of Superposition<\/strong>: The scientific law that states that rock and soil are deposited in layers, with the youngest layers on top and the oldest layers on the bottom.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Lithification<\/strong>: The process by which the pressure of sediments squeeze extra water out of decaying remains and replace the voids that appear with minerals from the surrounding soil and groundwater.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Luminescence dating<\/strong>: The chronometric dating method based on the buildup of background radiation in pottery, clay, and soils.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Megafauna<\/strong>: Large animals such as mammoths and mastodons.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Mitochondrial DNA<\/strong>: DNA located in the mitochondria of a cell that is only passed down from biological mother to child.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Mya<\/strong>: Million years ago.<\/p>\n<p class=\"import-Normal\"><strong>P<\/strong><strong>aleopathology<\/strong>: Study of ancient diseases and injuries identified through examining remains.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Periods<\/strong>: Geologic time units that span millions of years and are subdivided into <em>epochs<\/em>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Permineralization<\/strong>: When minerals from water impregnate or replace organic remains, leaving a fossilized copy of the organism.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Petrified wood<\/strong>: A fossilized piece of wood in which the original organism is completely replaced by minerals through petrifaction.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Potassium-argon (K-Ar) dating<\/strong>: A chronometric dating method that measures the ratio of argon gas in volcanic rock to estimate time elapsed since the volcanic rock cooled and solidified. See also <em>argon-argon dating<\/em>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Pseudofossils<\/strong>: Natural rocks or mineral formations that can be mistaken for fossils.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Radioactive decay<\/strong>: The process of transforming the atom by spontaneously releasing energy.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Radiocarbon dating<\/strong>: The chronometric dating method based on the radioactive decay of <sup>14<\/sup>C in organic remains.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Relative dating<\/strong>: Dating methods that do not result in numbers of years but, rather, in relative timelines wherein some organisms or artifacts are older or younger than others.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Sediment cores<\/strong>: Core samples taken from lake beds or other water sources for analysis of their pollen.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Stable isotopes<\/strong>: Variants of elements that do not change over time without outside interference.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Stratigraphy<\/strong>: A relative dating method that is based on ordered layers or (strata) that build up over time.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Taphonomy<\/strong>: The study of what happens to an organism after death.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Trace fossils<\/strong>: Fossilized remains of activity such as footprints.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Uniformitarianism<\/strong>: The theoretical perspective that the geologic processes observed today are the same as the processes operating in the past.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Unstable isotopes<\/strong>: Variants of elements that spontaneously change into stable isotopes over time.<\/p>\n<p class=\"import-Normal\"><strong>Uranium series dating<\/strong>: A radiometric dating method based on the decay chain of unstable isotopes of <sup>238<\/sup>U and <sup>235<\/sup>U.<\/p>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">About the Authors<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image9-1.jpg\" alt=\"A woman with curly blonde hair and sunglasses smiles in front of a mountain landscape.\" width=\"179\" height=\"250\" \/><\/p>\n<h3 class=\"import-Normal\">Sarah S. King, Ph.D.<\/h3>\n<p class=\"import-Normal\">Cerro Coso Community College, sarah.king1@cerrocoso.edu<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dr. Sarah S. King is an anthropology\/sociology professor at Cerro Coso Community College in California. She completed her Ph.D. work at the Division of Archaeological, Geographical and Environmental Sciences at the University of Bradford in West Yorkshire, England. Her thesis was entitled \u201cWhat Makes War?: Assessing Iron Age Warfare through Mortuary Behavior and Osteological Patterns of Violence.\u201d She also holds anthropology degrees from the University of California, Santa Cruz (B.A. hons., 2004), and the University of New Mexico, Albuquerque (M.A., 2006).<\/p>\n<p>&nbsp;<\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><img loading=\"lazy\" decoding=\"async\" class=\"alignleft wp-image-253\" src=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390.jpg\" alt=\"A person with short, curly brown hair and glasses smiles at the camera.\" width=\"180\" height=\"254\" srcset=\"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390.jpg 406w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390-213x300.jpg 213w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390-65x92.jpg 65w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390-225x318.jpg 225w, https:\/\/opentextbooks.concordia.ca\/explorations\/wp-content\/uploads\/sites\/57\/2023\/08\/image3-e1684810044390-350x494.jpg 350w\" sizes=\"auto, (max-width: 180px) 100vw, 180px\" \/>Kara Jones, M.A.<\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">PhD student at University of Nevada, Las Vegas, jonesk44@unlv.nevada.edu<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Kara Jones received their B.A. in anthropology at California State University, Bakersfield (2018) and their M.A. from University of Nevada, Las Vegas (2023, summer). Their master\u2019s thesis is titled \u201cRockin\u2019 at the Lake: Toolstone Use and Procurement along Holocene Lake Ivanpah, CA.\u201d Mx Jones is a Mojave Desert archaeologist specializing in stone tool use and manufacture, focusing further on Holocene lakeshore adaptations.<\/p>\n<\/div>\n<h2>For Further Exploration<\/h2>\n<div class=\"__UNKNOWN__\">\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Books<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Bjornerud, Marcia. 2006. <em>Reading the Rocks: The Autobiography of the Earth<\/em>. New York: Basic Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hazen, Robert M. 2013. <em>The Story of Earth: The First 4.5 Billion Years, From Stardust to Living Planet<\/em>. New York: Viking Penguin.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Holmes, Richard. 2010. <em>The Age of Wonder: The Romantic Generation and the Discovery of the Beauty and Terror of Science<\/em>. New York: Vintage.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Palmer, Douglas. 2005. <em>Earth Time: Exploring the Deep Past from Victorian England to the Grand Canyon<\/em>. New York: John Wiley &amp; Sons.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Prothero, Donald R. 2015. <em>The Story of Life in 25 Fossils: Tales of Intrepid Fossil Hunters and the Wonder of Evolution<\/em>. New York: Columbia University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Pyne, Lydia. 2016. <em>Seven Skeletons: The Evolution of the World\u2019s Most Famous Human Fossils<\/em>. New York: Viking Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Repcheck, Jack. 2009. <em>The Man Who Found Time: James Hutton and the Discovery of the Earth\u2019s Antiquity<\/em>. New York: Basic Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taylor, Paul D., Aaron O\u2019Dea. 2014. <em>A History of Life in 100 Fossils<\/em>. Washington, DC: Smithsonian Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ward, David. 2002. <em>Smithsonian Handbooks: Fossils<\/em>. Washington, DC: Smithsonian Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Winchester, Simon. 2009. <em>The Map That Changed the World: William Smith and the Birth of Modern Geology<\/em>. New York: Harper Perennial.<\/p>\n<h3 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><strong>Websites<\/strong><\/h3>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.ambermuseum.eu\/en\/\">Amber Museum<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.etsu.edu\/cas\/paleontology\/\">East Tennessee State University Center of Excellence in Paleontology<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.granger.com\/\">Granger Historical Picture Archive<\/a><\/p>\n<p class=\"import-Normal\"><a href=\"https:\/\/www.facebook.com\/indigarchs\/\">Indigenous Archaeology Collective<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/tarpits.org\">La Brea Tar Pits Museum<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.lymeregismuseum.co.uk\">Lyme Regis Museum<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.nhm.ac.uk\/discover\/mary-anning-unsung-hero.html\">Natural History Museum (London), on Mary Anning<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/en.pechmerle.com\">Pech Merle Cave<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/www.nps.gov\/pefo\/index.htm\">Petrified Forest National Park (NE Arizona)<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/poozeum.com\">Poozeum: The No. 2 Wonder of the World<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\"><a href=\"https:\/\/paleobiology.si.edu\/fossiLab\/projects.html\">Smithsonian National Museum of Natural History, Department of Paleobiology<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Smithsonian National Museum of Natural History, on <a href=\"https:\/\/humanorigins.si.edu\">\u201cWhat Does It Mean to be Human\u201d<\/a><\/p>\n<p class=\"import-Normal\">Society for American Archaeology, on <a href=\"https:\/\/www.saa.org\/career-practice\/ethics-in-professional-archaeology\">\u201cEthics in Professional Archaeology\u201d<\/a><\/p>\n<p class=\"import-Normal\">Society for American Archaeology, <a href=\"https:\/\/archaeologicalethics.org\/code-of-ethics\/society-for-american-archaeology-principles-of-archaeological-ethics\/\">\u201cPrinciples of Archaeological Ethics\u201d<\/a><\/p>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">References<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Antoine, Pierre-Oliver, Maeva J. Orliac, Gokhan Atici, Inan Ulusoy, Erdal Sen, H. Evren \u00c7ubuk\u00e7u, Ebru lbayrak, Ne\u015fe Oyal, Erkan Aydar, and Sevket Sen. 2012. \u201cA Rhinocerotid Skull Cooked to Death in a 9.2 Mya-Old Ignimbrite Flow of Turkey.\u201d <em>PLoS ONE<\/em> 7 (11): e49997.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Aufderheide, Arthur C. 2003. <em>The Scientific Study of Mummies<\/em>. Cambridge, UK: Cambridge University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Bar-Yosef, O., and M. Belmaker. 2011. \u201cEarly and Middle Pleistocene Faunal and Hominins Dispersals through Southwestern Asia.\u201d<em> Quaternary Science Reviews<\/em> 30 (11\u201312): 1318\u20131337.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Barras, C. 2022. \u201cLost Footprints of Our Ancestors.\u201d <em>New Scientist<\/em> 254 (3381): 40\u201344.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Blong, John C., Martin E. Adams, Gabriel Sanchez, Dennis L. Jenkins, Ian D. Bull, and Lisa-Marie Shillito. 2020. \u201cYounger Dryas and Early Holocene Subsistence in the Northern Great Basin: Multiproxy Analysis of Coprolites from the Paisley Caves, Oregon, USA.\u201d <em>Archaeological and Anthropological Sciences<\/em> 12 (9): 1\u201329.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Boaz, Noel T., Russel L. Ciochon, Qinqi Xu, and Jinyi Liu. 2004. \u201cMapping and Taphonomic Analysis of the <em>Homo erectus<\/em> Loci at Locality 1 Zhoukoudian, China.\u201d <em>Journal of Human Evolution <\/em>46 (5): 519\u2013549.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Booth, Thomas J., Andrew T. Chamberlain, and Mike Parker Pearson. 2015. \u201cMummification in Bronze Age Britain.\u201d <em>Antiquity<\/em> 89 (347): 1,155\u20131,173.<\/p>\n<p class=\"import-Normal\">Bradley, Raymond S. 2015. \u201cChapter 3: Dating Methods I.\u201d In <em>Paleoclimatology<\/em>, edited by Raymond S. Bradley, 55\u2013101. Cambridge, MA: Academic Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Brown, Theodore L., H. Eugene LeMay Jr., Bruce E. Burston, Catherine J. Murphy, Patrick M. Woodward, and Matthew Stoltzfus. 2018. <em>Chemistry: The Central Science.<\/em> New York: Pearson.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Campbell, Neil A., and Jane B. Reece. 2005. <em>Biology 7th ed. <\/em>New York: Pearson.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Carvajal, Eduar, Luis Montes, and Ovidio A. Almanza. 2011. \u201cQuaternary Dating by Electron Spin Resonance (ESR) Applied to Human Tooth Enamel.\u201d <em>Earth Sciences Research Journal<\/em> 15 (2): 115\u2013120.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Chatters, James C., Joaquin Arroyo-Cabrales, and Pilar Luna-Erreguerena. 2022. \u201cThe Pre-Ceramic Skeletal Record of Mexico and Central America.\u201d In <em>The Routledge Handbook of Mesoamerican Bioarchaeology,<\/em> edited by V. Tieslar, 49\u201374. New York: Routledge.<\/p>\n<p class=\"import-Normal\">Chatters, James C., Douglas J. Kennett, Yemane Asmerom, Brian M. Kemp, Victor Polyak, Alberto Nava Blank, Patricia A. Beddows, et al. 2014. \u201cLate Pleistocene Human Skeleton and mtDNA Link Paleoamericans and Modern Native Americans.\u201d <em>Science<\/em> 344 (6185): 750\u2013754.<\/p>\n<p class=\"import-Normal\">Clough, Sharon. 2020. &#8220;Ethics in Human Osteology.&#8221; <em>The Archaeologist<\/em> 109 (2020): 3\u20135.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cochrane, Grant W. G., Trudy Doelman, and Lyn Wadley. 2013. \u201cAnother Dating Revolution for Prehistoric Archaeology?\u201d <em>Journal of Archaeological Method and Theory<\/em> 20 (1): 42\u201360.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Collins, S. V., E. G. Reinhardt, D. Rissolo, J. C. Chatters, A. Nava-Blank, and P. Luna-Erreguerena. 2015. \u201cReconstructing Water Level in Hoyo Negro, Quintana Roo, Mexico: Implications for Early Paleoamerican and Faunal Access.\u201d <em>Quaternary Science Reviews <\/em>124: 68\u201383.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cook, Harold J. 1928. \u201cGlacial Age Man in New Mexico.\u201d <em>Scientific American<\/em> 139 (1): 38\u201340.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cook, S. F., and H. C. Ezra-Cohn. 1959. \u201cAn Evaluation of the Fluorine Dating Method.\u201d <em>Southwestern Journal of Anthropology <\/em>15 (3): 276\u2013290.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Cooper, Arnie. 2010. \u201cSticky Situation at the Tar Pits.\u201d <em>LA Weekly<\/em>, May 27, 2010. https:\/\/www.laweekly.com\/sticky-situation-at-the-tar-pits\/.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Crompton, Robin H., Todd C. Pataky, Russell Savage, Kristiaan D\u2019Ao\u00fbt, Matthew R. Bennett, Michael H. Day, Karl Bates, Sarita Morse, and William I. Sellers. 2012. \u201cHuman-like External Function of the Foot, and Fully Upright Gait, Confirmed in the 3.66 Million Year Old Laetoli Hominin Footprints by Topographic Statistics, Experimental Footprint-Formation and Computer Simulation.\u201d <em>Journal of the Royal Society Interface<\/em> 9 (69): 707\u2013719. doi: 10.1098\/rsif.2011.0258<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Crutzen, Paul J., and Eugene F. Stoermer. 2000. \u201cThe \u2018Anthropocene.\u2019\u201d <em>Global Change Newsletter<\/em> 41: 17\u201318.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Darwin, Charles. 1859. <em>On the Origin of Species<\/em>. London, UK: John Murray.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dean, Jeffery S. 2009. \u201cOne Hundred Years of Dendroarchaeology: Dating, Human Behavior, and Past Climate.\u201d In <em>Tree-rings, Kings, and Old World Archaeology and Environment: Papers Presented in Honor of Peter Ian Kuniholm<\/em>, edited by S. Manning and M. J. Bruce, 25\u201332. Oxford, UK: Oxbow Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Dolnick, Edward. 2011. <em>The Clockwork Universe: Isaac Newton, the Royal Society, and the Birth of the Modern World<\/em>. New York: HarperCollins.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Duller, G.A.T. 2008. <em>Luminescence Dating: Guidelines on Using Luminescence Dating in Archaeology<\/em>. Swindon, UK: English Heritage.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Eisenbeiss, Sabine. 2016. \u201cPreserved in Peat: Decoding Bodies from Lower Saxony, Germany.\u201d <em>Expedition<\/em> 58 (2): 18\u201321.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Emling, Shelley. 2009. <em>The Fossil Hunter: Dinosaurs, Evolution, and the Woman Whose Discoveries Changed the World<\/em>. New York: St. Martin\u2019s Griffin.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Faux, Jennifer L. 2012. \u201cHail the Conquering Gods: Ritual Sacrifice of Children in Inca Society.\u201d <em>Journal of Contemporary Anthropology<\/em> 3 (1): 1\u201315.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Feder, Kenneth L. 2017. <em>The Past in Perspective: An Introduction to Human Prehistory<\/em>. 7th ed. New York: Oxford University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Fletcher, Michael-Shawn, Tegan Hall, and Andreas Nicholas Alexandra. 2021. \u201cThe Loss of an Indigenous Constructed Landscape Following British Invasion of Australia: An Insight into the Deep Human Imprint on the Australian Landscape.\u201d <em>Ambio<\/em> 50 (1): 138\u2013149.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Flowers, Paul, Klaus Theopold, Richard Langley, and William R. Robinson. 2018. <em>Chemistry<\/em>. Houston, TX: Openstax, Rice University.<\/p>\n<p class=\"import-Normal\">Fumagalli, Matteo, Ida Moltke, Niels Grarup, Fernando Racimo, Peter Bjerregaard, Marit E. J\u00f8rgensen, Thorfinn S. Korneliussen, Pascale Gerbault, Line Skotte, Allan Linneberg, Cramer Christensen, Ivan Brandslund, Torben J\u00f8rgensen, Emilia Huerta-S\u00e1nchez, Erik B. Schmidt, Oluf Pedersen, Torben Hansen, Anders Albrechtsen, and Rasmus Nielsen. 2015. \u201cGreenlandic Inuit show genetic signatures of diet and climate adaptation.\u201d <em>Science<\/em> 349 (6254): 1343-1347.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Funkhouser, J. G., I. L. Barnes, and J. J. Naughton. 1966. \u201dProblems in the Dating of Volcanic Rocks by the Potassium-Argon Method.\u201d<em> Bull Volcanol<\/em> 29: 709\u2013717.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Giles, Melanie. 2020. <em>Bog Bodies: Face to Face with the Past.<\/em> Manchester, UK: Manchester University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Goodrum, Matthew R., and Cora Olson. 2009. \u201cThe Quest for an Absolute Chronology in Human Prehistory: Anthropologists, Chemists, and the Fluorine Dating Method in Palaeoanthropology.\u201d <em>British Journal for the History of Science<\/em> 42 (1): 95\u2013114.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Granger, Darryl E., Ryan J. Gibbon, Kathleen Kuman, Ronald J. Clarke, Laurent Bruxelles, and Marc W. Caffee. 2015. \u201cNew Cosmogenic Burial Ages for Sterkfontein Member 2 <em>Australopithecus<\/em> and Member 5 Oldowan.\u201d <em>Nature<\/em> 522 (7554): 85\u201388.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Granger Historical Picture Archive. 2018. <em>Cro-Magnon Footprint<\/em>. Image no. 0167868. Accessed March, 02, 2023. <a class=\"rId129\" href=\"https:\/\/www.granger.com\/results.asp?image=0167868&amp;itemw=4&amp;itemf=0001&amp;itemstep=1&amp;itemx=11&amp;screenwidth=1085\">https:\/\/www.granger.com\/results.asp?image=0167868&amp;itemw=4&amp;itemf=0001&amp;itemstep=1&amp;itemx=11&amp;screenwidth=1085<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Gruhn, R., 2020. \u201cEvidence Grows That Peopling of the Americas Began More Than 20,000 Years Ago.\u201d <em>Nature<\/em> 584: 47\u201348.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Haddy, A., and A. Hanson. 1982. \u201cResearch Notes and Application Reports Nitrogen and Fluorine Dating of Moundville Skeletal Samples. <em>Archaeometry<\/em> 24 (1): 37\u201344.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hajdas, I., P. Ascough, M. H. Garnett, S. J. Fallon, C. L. Pearson, G. Quarta, K. L. Spalding, H. Yamaguchi, and M. Yoneda. 2021. \u201cRadiocarbon Dating.\u201d <em>Nature Reviews Methods Primers<\/em> 1 (62): 1\u201326.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hatala, Kevin G., Brigitte Demes, and Brian G. Richmond. 2016. \u201cLaetoli Footprints Reveal Bipedal Gait Biomechanics Different from Those of Modern Humans and Chimpanzees.\u201d <em>Proceedings of the Royal Society B<\/em> 283: 20160235. <a class=\"rId130\" href=\"https:\/\/dx.doi.org\/10.1098\/rspb.2016.0235\">https:\/\/dx.doi.org\/10.1098\/rspb.2016.0235<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hester, Thomas R., Harry J. Shafer, and Kenneth L. Feder. 1997. <em>Field Methods in Archaeology<\/em>, 7th ed. Mountain View, CA: Mayfield Publishing.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Hillam, J., C. M. Groves, D. M. Brown, M. G. L. Baillie, J. M. Coles, and B. J. Coles. 1990. \u201cDendrochronology of the English Neolithic.\u201d <em>Antiquity<\/em> 64 (243): 210\u2013220.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Holmes, Richard. 2010. <em>The Age of Wonder: How the Romantic Generation Discovered the Beauty and Terror of Science<\/em>. New York: Vintage.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ingber, Sasha. 2012. \u201cVolcano Eruption Baked Rare Rhino Fossil.\u201d <em>National Geographic News<\/em>, November 30, 2012. Accessed July 25, 2018. https:\/\/www.nationalgeographic.com\/science\/article\/121130-rare-rhino-fossil-created-by-volcanic-explosion.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Jay, Mandy, B. T. Fuller, Michael P. Richards, Christopher J. Kn\u00fcsel, and Sarah S. King. 2008. \u201cIron Age Breastfeeding Practices in Britain: Isotopic Evidence from Wetwang Slack, East Yorkshire.\u201d <em>American Journal of Physical Anthropology<\/em> 136 (3): 327\u2013337.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Jones, Nicola. 2020. \u201cCarbon Dating, the Archaeological Workhorse, Is Getting a Major Reboot.\u201d <em>Nature<\/em><em> News<\/em>, May 19, 2020. doi: <a class=\"rId131\" href=\"https:\/\/doi.org\/10.1038\/d41586-020-01499-y\">https:\/\/doi.org\/10.1038\/d41586-020-01499-y<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Klein, Richard G. 1999. <em>The Human Career: Human Biological and Cultural Origins<\/em>, 2nd ed. Chicago: University of Chicago Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Komar, Debra A., and Jane E. Buikstra. 2008. <em>Forensic Anthropology: Contemporary Theory and Practice<\/em>. New York: Oxford University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Kuniholm, Peter Ian, and Cecil L. Striker. 1987. \u201cDendrochronological Investigations in the Aegean and Neighboring Regions, 1983\u20131986.\u201d <em>Journal of Field Archaeology<\/em> 14 (4): 385\u2013398.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Laurenzi, Marinella A., Maria Laura Balestrieri, Giulio Bigazzi, Julio C. Hadler Neto, Pedro J. Iunes, Pio Norelli, Massimo Oddone, Ana Maria Osorio Araya, and Jos\u00e9 G. Viramonte. 2007. \u201cNew Constraints on Ages of Glasses Proposed as Reference Materials for Fission-Track Dating.\u201d <em>Geostandards &amp; Geoanalytical Research<\/em> 31 (2): 105\u2013124.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Lebatard, Anne-Elisabeth, Didier L. Bourl\u00e8s, Philippe Duringer, Marc Jolivet, R\u00e9gis Braucher, Julien Carcaillet, Mathieu Schuster, et al. 2008. \u201cCosmogenic Nuclide Dating of <em>Sahelanthropus tchadensis<\/em> and <em>Australopithecus bahrelghazali<\/em>: Mio-Pliocene Hominids from Chad.\u201d <em>Proceedings of the National Academy of Sciences<\/em> 105 (9): 3226\u20133231.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Lyell, Charles. 1830\u20131833. <em>Principles of Geology, Being an Attempt to Explain the Former Changes of the Earth\u2019s Surface, by Reference to Causes Now in Operation<\/em>. 3 vols. London: John Murray.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Maixner, Frank, Dmitrij Turaev, Amaury Cazenave-Gassiot, Marek Janko, Ben Krause-Kyora, Michael R. Hoopmann, Ulrike Kusebauch, et al. 2018. \u201cThe Iceman\u2019s Last Meal Consisted of Fat, Wild Meat, and Cereals.\u201d <em>Current Biology<\/em> Report 28 (14): 2348\u20132355.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Masao, Fidelis T., Elgidius B. Ichumbaki, Marco Cherin, Angelo Barili, Giovanni Boschian, David A. Lurino, Sofia Menconero, Jacopo Moggi-Cecchi, and Giorgio Manzi. 2016. \u201cNew Footprints from Laetoli (Tanzania) Provide Evidence for Marked Body Size Variation in Early Hominins.\u201d\u00a0<em>eLife <\/em>5: e19568. <a class=\"rId132\" href=\"https:\/\/elifesciences.org\/articles\/19568\">https:\/\/elifesciences.org\/articles\/19568<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">McDonough, Katelyn, Taryn Johnson, Ted Goebel, and Karl Reinhard. 2022. \u201cDisease, Diet, and Thorny Headed Worm Infection in the Great Basin.\u201d Paper presented at 50th Annual Meeting of the Nevada Archaeological Association, Tonopah, Nevada, April 22nd, 2022.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Michels, Joseph W. 1972. \u201cDating Methods.\u201d <em>Annual Review of Anthropolog<\/em>y 1: 113\u2013126.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Monastersky, Richard. 2015. \u201cAnthropocene: The Human Age.\u201d <em>Nature<\/em> 519 (7542): 144\u2013147.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Montgomery, Janet, Jane A. Evans, Dominic Powlesland, and Charlotte A. Roberts. 2005. \u201cContinuity or Colonization in Anglo-Saxon England? Isotope Evidence for Mobility, Subsistence Practice, and Status at West Heslerton.\u201d <em>American Journal of Physical Anthropology<\/em> 126 (2): 123\u2013138.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">National Park Service. 2022. \u201cFossilized Footprints.\u201d <em>National Park Service <\/em>website, February 1. Accessed May 31, 2022. https:\/\/www.nps.gov\/whsa\/learn\/nature\/fossilized-footprints.htm.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Pastoors, Andreas, Tilman Lenssen-Erz, Bernd Breuckmann, Tsamkxao Ciqae, Ui Kxunta, Dirk Rieke-Zapp, and Thui Thao. 2017. \u201cExperience Based Reading of Pleistocene Human Footprints in Pech-Merle.\u201d <em>Quaternary International <\/em>430 (A): 155\u2013162.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Potts, Richard. 2012. \u201cEvolution and Environmental Change in Early Human Prehistory.\u201d <em>Annual Review of Anthropology<\/em> 41: 151\u2013167.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Raichlen, David A., and Adam D. Gordon. 2017. \u201cInterpretation of Footprints From Site S Confirms Human-like Bipedal Biomechanics in Laetoli Hominins.\u201d <em>Journal of Human Evolution<\/em> 107: 134\u2013138.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ravn, Morten. 2010. \u201cBronze and Early Iron Age Bog Bodies from Denmark.\u201d <em>Acta Archaeologica<\/em> 81 (1): 112\u2013113.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Reimer, Paula J., Edouard Bard, Alex Bayliss, J. Warren Beck, Paul G. Blackwell, Christopher Bronk Ramsey, Caitlin E. Buck, et al. 2013. \u201cINTCAL13 and Marine13 Radiocarbon Age Calibration Curves 0\u201350,000 Years cal BP.\u201d <em>Radiocarbon<\/em> 55 (4): 1869\u20131887.<\/p>\n<p class=\"import-Normal\">Reinhard, Johan. 2006. <em>Ice Maiden: Inca Mummies, Mountain Gods, and Sacred Sites in the Andes<\/em>. Washington, DC.: National Geographic.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Reitz, Elizabeth J., and Elizabeth S. Wing. 1999. <em>Zooarchaeology<\/em>. Cambridge, UK: Cambridge University Press.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Renfrew, Colin, and Paul Bahn. 2016. <em>Archaeology: Theories, Methods, and Practice<\/em>, 7th ed. New York: Thames and Hudson.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Ruddiman, William F., Zhengtang Guo, Xin Zhou, Hanbin Wu, and Yanyan Yu. 2008. \u201cEarly Rice Farming and Anomalous Methane Trends.\u201d <em>Quaternary Science Reviews<\/em> 27 (13\u201314): 1291\u20131295.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Schmidt, Gavin. 1999. \u201cScience Briefs: Cold Climates, Warm Climates: How Can We Tell Past Temperatures?\u201d <em>National Aeronautics and Space Administration Goddard Institute for Space Studies<\/em>. <a class=\"rId133\" href=\"https:\/\/www.giss.nasa.gov\/research\/briefs\/1999_schmidt_01\/\">https:\/\/www.giss.nasa.gov\/research\/briefs\/1999_schmidt_01\/<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Shillito, Lisa-Marie, John C. Blong, Eleanor J. Green, and Eline N. van Asperen. 2020a. \u201cThe What, How and Why of Archaeological Coprolite Analysis.\u201d <em>Earth-Science Reviews<\/em> 207. <a class=\"rId134\" href=\"https:\/\/doi.org\/10.1016\/j.earscirev.2020.103196\">https:\/\/doi.org\/10.1016\/j.earscirev.2020.103196<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Shillito, Lisa-Marie, Helen L. Whelton, John C. Blong, Dennis L. Jenkins, Thomas J. Connolly, and Ian D. Bull. 2020b. \u201cPre-Clovis occupation of the Americas Identified by Human Fecal Biomarkers in Coprolites from Paisley Caves, Oregon.\u201d <em>Science Advances<\/em> 6 (29).\u200b\u200b https:\/\/www.science.org\/doi\/10.1126\/sciadv.aba6404.<\/p>\n<p class=\"import-Normal\">Sims, Douglas., and W. Spaulding. 2017. \u201cShallow Subsurface Evidence for Postglacial Holocene Lakes at Ivanpah Dry Lake: An Alternative Energy Development Site in the Central Mojave Desert, California, USA.\u201d <em>Journal of Geography and Geology<\/em> 9 (1): 1\u201324. DOI: <a class=\"rId135\" href=\"https:\/\/doi.org\/10.5539\/jgg.v9n1p1\">10.5539\/jgg.v9n1p1<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Slon, Viviane, Fabrizio Mafessoni, Benjamin Vernot, Cesare De Filippo, Steffi Grote, Bence Viola, Mateja Hajdinjak, St\u00e9phane Peyr\u00e9gne, Sarah Nagel, Samantha Brown, et al. 2018. \u201cThe Genome of the Offspring of a Neanderthal Mother and a Denisovan Father.\u201d <em>Nature<\/em> 561 (7721): 113\u2013116.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Smithsonian National Museum of Natural History. 2018. Laetoli Footprint Trails. Smithsonian National Museum of History, October 23. Accessed February 14, 2023. <a class=\"rId136\" href=\"https:\/\/humanorigins.si.edu\/evidence\/behavior\/footprints\/laetoli-footprint-trails\">https:\/\/humanorigins.si.edu\/evidence\/behavior\/footprints\/laetoli-footprint-trails<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Snoeck, Christophe, John Pouncett, Philippe Claeys, Steven Goderis, Nadine Mattielli, Mike Parker Pearson, Christie Willis, Antoine Zazzo, Julia A. Lee-Thorp, and Rick J. Schulting. 2018. \u201cStrontium Isotope Analysis on Cremated Human Remains from Stonehenge Support[sic] Links With West Wales.\u201d <em>Scientific Reports <\/em>8. <a class=\"rId137\" href=\"https:\/\/www.nature.com\/articles\/s41598-018-28969-8\">https:\/\/www.nature.com\/articles\/s41598-018-28969-8<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Spaulding, W. G., and D. B. Sims. 2018. \u201cA Glance to the East: Lake Ivanpah\u2014An Isolated Southern Great Basin Paleolake. <em>The 2018 Desert Symposium Field Guide and Proceedings<\/em>, 121-131. <a class=\"rId138\" href=\"https:\/\/www.researchgate.net\/publication\/340493333_A_glance_to_the_east_Lake_Ivanpah-_an_isolated_southern_Great_Basin_paleolake\">https:\/\/www.researchgate.net\/publication\/340493333_A_glance_to_the_east_Lake_Ivanpah-_an_isolated_southern_Great_Basin_paleolake<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Spray, Aaron. \u201cLa Brea Woman: Only (&amp; Controversial) Human from La Brea Tar Pits.\u201d <em>The Travel<\/em>, April 3, 2022. Accessed July 31, 2022. <a class=\"rId139\" href=\"https:\/\/www.thetravel.com\/what-to-know-of-the-la-brea-woman\/\">https:\/\/www.thetravel.com\/what-to-know-of-the-la-brea-woman\/<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Steffen, Will, Johan Rockstr\u00f6m, Katherine Richardson, Timothy M. Lenton, Carl Folke, Diana Liverman, Colin P. Summerhayes, et al. 2018. \u201cTrajectories of the Earth System in the Anthropocene.\u201d <em>PNAS <\/em>115 (33): 8252\u20138259.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Stodder, Ann L. W. 2008. \u201cTaphonomy and the Nature of Archaeological Assemblages.\u201d In <em>Biological Anthropology of the Human Skeleton<\/em>, edited by M. Anne Katzenberg and Shelley R. Saunders, 71\u2013115. Hoboken, NJ: Wiley Blackwell.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Straus, Lawrence Guy. 1989. \u201cGrave Reservations: More on Paleolithic Burial Evidence.\u201d <em>Current Anthropology<\/em> 30 (5): 633\u2013634.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Sullivan, Terry, and Harry Gifford. 1908. <em>She Sells Sea-Shells<\/em>. London: Francis, Day, and Hunter.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taylor, Anthony, Jarod M. Hutson, Vaughn M. Bryant, and Dennis L. Jenkins. 2020. \u201cDietary Items in Early to Late Holocene Human Coprolites from Paisley Caves, Oregon, USA.\u201d <em>Palynology<\/em> 44 (1): 12\u201323.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Taylor, Paul D., Aaron O\u2019Dea. 2014. <em>A History of Life in 100 Fossils<\/em>. Washington, D.C.: Smithsonian Books.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">T\u00f6rnqvist, T. E., B. E. Rosenheim, P. Hu, and A. B. Fernandez. 2015. \u201cRadiocarbon Dating and Calibration.\u201d In <em>Handbook of Sea-Level Research<\/em>, edited by Ian Shennan, Antony J. Long, and Benjamin P. Horton, 347-360. Oxford, UK: John Wiley &amp; Sons. <a class=\"rId140\" href=\"https:\/\/doi.org\/10.1002\/9781118452547.ch23\">https:\/\/doi.org\/10.1002\/9781118452547.ch23<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">University of Arizona. n.d. \u201cUranium-Thorium Dating: The Uranium 238 Decay Series.\u201d Accessed November 21, 2022. <a class=\"rId141\" href=\"https:\/\/www.geo.arizona.edu\/Antevs\/ecol438\/uthdating.html\">https:\/\/www.geo.arizona.edu\/Antevs\/ecol438\/uthdating.html<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">University of the Witwatersrand. 2017. \u201cLittle Foot Takes a Bow: South Africa\u2019s Oldest and the World\u2019s Most Complete <em>Australopithecus<\/em> Skeleton Ever Found, Introduced to the World.\u201d <em>ScienceDaily<\/em>, December 6. Accessed February 14, 2023. <a class=\"rId142\" href=\"https:\/\/www.sciencedaily.com\/releases\/2017\/12\/171206100104.htm\">https:\/\/www.sciencedaily.com\/releases\/2017\/12\/171206100104.htm<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">van Calsteren, Peter, and Louise Thomas. 2006. \u201cUranium-Series Dating Applications in Natural Environmental Science.\u201d <em>Earth-Science Reviews<\/em> 75 (1\u20134): 155\u2013175.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Vanzetti, A., M. Vidale, M. Gallinaro, D. W. Frayer, and L. Bondioli. 2010. \u201cThe Iceman as a Burial.\u201d <em>Antiquity<\/em> 84 (325): 681\u2013692. <a class=\"rId143\" href=\"https:\/\/doi.org\/10.1017\/S0003598X0010016X\">https:\/\/doi.org\/10.1017\/S0003598X0010016X<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Verghese, Namrata. 2021. \u201cWhat Is Necropolitics? The Political Calculation of Life and Death.\u201d <em>Teen Vogue<\/em>. March 10, 2021. Accessed February 14, 2023. https:\/\/www.teenvogue.com\/story\/what-is-necropolitics.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Vidale, M., L. Bondioli, D. W. Frayer, M. Gallinaro, and A. Vanzetti. 2016. \u201c\u00d6tzi the Iceman.\u201d <em>Expedition<\/em> 58 (2): 13\u201317. Accessed February 14, 2023. <a class=\"rId144\" href=\"https:\/\/www.penn.museum\/sites\/expedition\/otzi-the-iceman\/\">https:\/\/www.penn.museum\/sites\/expedition\/otzi-the-iceman\/<\/a>.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wade, Lizzie. 2021. &#8220;Footprints Support Claim of Early Arrival in the Americas.&#8221; <em>Science <\/em>373 (6562): 1426. Accessed February 14, 2023. https:\/\/www.sciencemagazinedigital.org\/sciencemagazine\/24_september_2021\/MobilePagedArticle.action?articleId=1727132#articleId1727132.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Waters, Colin N., Jan Zalasiewicz, Anthony D. Barnosky, Alejandro Cearreta, Agieszka Galuszka, Juliana A. Ivar Do Sul, Catherine Jeandel, et al. 2016 \u201cIs the Anthropocene Distinct from the Holocene?\u201d <em>Science <\/em>351 (6269): aad2622-1-10. DOI:<a class=\"rId145\" href=\"https:\/\/dx.doi.org\/10.1126\/science.aad2622\">10.1126\/science.aad2622<\/a><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Watson, Traci. 2017. \u201cAncient Bones Reveal Girl\u2019s Tough Life in Early Americas.\u201d <em>Nature <\/em>544 (7648): 15\u201316<em>. <\/em><\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wendt, Kathleen, A., Xianglei Li,, and R. Lawrence Edwards. 2021. \u201cUranium-Thorium Dating of Speleothems.\u201d Elements 17 (2): 87\u201392.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">White, Tim D. 1986. \u201cCut Marks on the Bodo Cranium: A Case of Prehistoric Defleshing.\u201d <em>American Journal of Physical Anthropology<\/em> 69 (4): 503\u2013509.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Williams, Linda D. 2004. <em>Earth Science Demystified<\/em>. New York: McGraw-Hill Professional.<\/p>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Wilson, Andrew S., Timothy Taylor, Maria Constanza Ceruti, Jose Antonio Chavez, Johan Reinhard, Vaughan Grimes, Wolfram Meier-Augenstein, et al. 2007. \u201cStable Isotope and DNA Evidence for Ritual Sequences in Inca Child Sacrifice.\u201d <em>PNAS<\/em> 104 (42): 16456\u201316461.<\/p>\n<h2 class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">Acknowledgments<\/h2>\n<p class=\"import-Normal\" style=\"margin-left: 0pt; text-indent: 0pt;\">We are grateful to Lee Anne Zajicek, who coauthored the first edition. Her original contributions continue to be an integral part of this chapter. We thank the staff of the Maturango Museum, Ridgecrest, California. Specifically, for their generous help with photography and fossil images, we acknowledge Debbie Benson, executive director; Alexander K. Rogers, former archaeology curator; Sherry Brubaker, natural history curator; and Elaine Wiley, history curator. We thank Sharlene Paxton, a librarian at Cerro Coso Community College, Ridgecrest, California, for her guidance and expertise with OER and open-source images, and John Stenger-Smith and Claudia Sellers from Cerro Coso Community College, Ridgecrest, California, for their feedback on the chemistry and plant biology content. Finally, we thank William Zajicek and Lauren Zajicek, our community college students, for providing their impressions and extensive feedback on early drafts of the chapter.<\/p>\n<\/div>\n<div class=\"glossary\"><span class=\"screen-reader-text\" id=\"definition\">definition<\/span><template id=\"term_254_826\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_826\"><div tabindex=\"-1\"><p>James Hutton\u2019s theory that the world was much older than biblical explanations allowed. This age could be determined by gradual natural processes like soil erosion.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_828\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_828\"><div tabindex=\"-1\"><p>The slow movement of continents over time.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_830\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_830\"><div tabindex=\"-1\"><p>The theoretical perspective that the geologic processes observed today are the same as the processes operating in the past.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_832\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_832\"><div tabindex=\"-1\"><p>Mineralized copies of organisms or activity imprints.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_844\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_844\"><div tabindex=\"-1\"><p>Billion years ago.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_836\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_836\"><div tabindex=\"-1\"><p>Units of geologic time that span millions to billions of years and that are subdivided into periods and epochs.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_838\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_838\"><div tabindex=\"-1\"><p>Geologic time units that span millions of years and are subdivided into epochs.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_846\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_846\"><div tabindex=\"-1\"><p>The smallest units of geologic time, spanning thousands to millions of years.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_840\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_840\"><div tabindex=\"-1\"><p>The geologic epoch from 10 kya to present.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_842\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_842\"><div tabindex=\"-1\"><p>Thousand years ago.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_848\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_848\"><div tabindex=\"-1\"><p>The proposed name for our current geologic epoch based on human-driven climate change.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_850\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_850\"><div tabindex=\"-1\"><p>The study of what happens to an organism after death.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_852\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_852\"><div tabindex=\"-1\"><p>The process by which an organism becomes a fossil.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_854\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_854\"><div tabindex=\"-1\"><p>An oxygen-free environment.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_856\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_856\"><div tabindex=\"-1\"><p>The process by which the pressure of sediments squeeze extra water out of decaying remains and replace the voids that appear with minerals from the surrounding soil and groundwater.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_858\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_858\"><div tabindex=\"-1\"><p>When minerals from water impregnate or replace organic remains, leaving a fossilized copy of the organism.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_860\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_860\"><div tabindex=\"-1\"><p>A fossilized piece of wood in which the original organism is completely replaced by minerals through petrifaction.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_862\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_862\"><div tabindex=\"-1\"><p>Million years ago.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_800\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_800\"><div tabindex=\"-1\"><p>Species that are regarded as human, directly ancestral to humans, or very closely related to humans.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_864\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_864\"><div tabindex=\"-1\"><p>Large animals such as mammoths and mastodons.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_866\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_866\"><div tabindex=\"-1\"><p>Fossilized remains of activity such as footprints.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_868\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_868\"><div tabindex=\"-1\"><p>Hard, concrete-like substances found in the intestines of fossil creatures.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_870\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_870\"><div tabindex=\"-1\"><p>Fossilized poop.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_872\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_872\"><div tabindex=\"-1\"><p>When a fossil is embedded in a substance, such as igneous rock.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_874\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_874\"><div tabindex=\"-1\"><p>Natural rocks or mineral formations that can be mistaken for fossils.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_876\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_876\"><div tabindex=\"-1\"><p>Dating methods that do not result in numbers of years but, rather, in relative timelines wherein some organisms or artifacts are older or younger than others.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_878\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_878\"><div tabindex=\"-1\"><p>A relative dating method that is based on ordered layers or (strata) that build up over time.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_880\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_880\"><div tabindex=\"-1\"><p>The scientific law that states that rock and soil are deposited in layers, with the youngest layers on top and the oldest layers on the bottom.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_882\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_882\"><div tabindex=\"-1\"><p>A relative dating method that uses other plant and animal remains occurring in the stratigraphic context to establish time depth.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_884\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_884\"><div tabindex=\"-1\"><p>The relative dating method that arranges human-made artifacts in a time frame from oldest to youngest based on material, production technique, style, and other features.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_886\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_886\"><div tabindex=\"-1\"><p>A relative dating method that analyzes the absorption of fluorine in bones from the surrounding soils.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_888\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_888\"><div tabindex=\"-1\"><p>Dating methods that give estimated numbers of years for artifacts and sites.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_890\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_890\"><div tabindex=\"-1\"><p>Matter that cannot be broken down into smaller matter.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_892\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_892\"><div tabindex=\"-1\"><p>A small building block of matter.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_894\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_894\"><div tabindex=\"-1\"><p>Variants of elements.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_896\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_896\"><div tabindex=\"-1\"><p>Variants of elements that do not change over time without outside interference.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_898\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_898\"><div tabindex=\"-1\"><p>Variants of elements that spontaneously change into stable isotopes over time.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_900\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_900\"><div tabindex=\"-1\"><p>The process of transforming the atom by spontaneously releasing energy.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_902\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_902\"><div tabindex=\"-1\"><p>The chronometric dating method based on the radioactive decay of 14C in organic remains.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_904\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_904\"><div tabindex=\"-1\"><p>A chronometric dating method that uses the annual growth of trees to build a timeline into the past.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_906\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_906\"><div tabindex=\"-1\"><p>Single-celled marine organisms with shells.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_908\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_908\"><div tabindex=\"-1\"><p>A chronometric dating method that measures the ratio of argon gas in volcanic rock to estimate time elapsed since the volcanic rock cooled and solidified.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_910\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_910\"><div tabindex=\"-1\"><p>A chronometric dating method that measures the ratio of argon gas in volcanic rock to estimate time elapsed since the volcanic rock cooled and solidified.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_912\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_912\"><div tabindex=\"-1\"><p>A radiometric dating method based on the decay chain of unstable isotopes of 238U and 235U.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_914\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_914\"><div tabindex=\"-1\"><p>A chronometric dating method that is based on the fission of 283U.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_916\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_916\"><div tabindex=\"-1\"><p>The chronometric dating method based on the buildup of background radiation in pottery, clay, and soils.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_918\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_918\"><div tabindex=\"-1\"><p>A chronometric dating method that measures the background radiation accumulated in material over time.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_920\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_920\"><div tabindex=\"-1\"><p>Core samples taken from lake beds or other water sources for analysis of their pollen.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_922\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_922\"><div tabindex=\"-1\"><p>The study of the physical characteristics of the Earth\u2019s surface.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_924\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_924\"><div tabindex=\"-1\"><p>Periods characterized by low global temperatures and the expansion of ice sheets on Earth\u2019s surface.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><template id=\"term_254_926\"><div class=\"glossary__definition\" role=\"dialog\" data-id=\"term_254_926\"><div tabindex=\"-1\"><p>DNA located in the mitochondria of a cell that is only passed down from biological mother to child.<\/p>\n<\/div><button><span aria-hidden=\"true\">&times;<\/span><span class=\"screen-reader-text\">Close definition<\/span><\/button><\/div><\/template><\/div>","protected":false},"author":1,"menu_order":7,"template":"","meta":{"pb_show_title":"on","pb_short_title":"","pb_subtitle":"","pb_authors":["beth-shook","ph-d","lara-braff","katie-nelson","kelsie-aguilera","m-a"],"pb_section_license":"cc-by-nc"},"chapter-type":[],"contributor":[60,63,64,62,65,61],"license":[55],"class_list":["post-254","chapter","type-chapter","status-publish","hentry","contributor-beth-shook","contributor-katie-nelson","contributor-kelsie-aguilera","contributor-lara-braff","contributor-m-a","contributor-ph-d","license-cc-by-nc"],"part":20,"_links":{"self":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/chapters\/254","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/chapters"}],"about":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/wp\/v2\/types\/chapter"}],"author":[{"embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/wp\/v2\/users\/1"}],"version-history":[{"count":16,"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/chapters\/254\/revisions"}],"predecessor-version":[{"id":1770,"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/chapters\/254\/revisions\/1770"}],"part":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/parts\/20"}],"metadata":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/chapters\/254\/metadata\/"}],"wp:attachment":[{"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/wp\/v2\/media?parent=254"}],"wp:term":[{"taxonomy":"chapter-type","embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/pressbooks\/v2\/chapter-type?post=254"},{"taxonomy":"contributor","embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/wp\/v2\/contributor?post=254"},{"taxonomy":"license","embeddable":true,"href":"https:\/\/opentextbooks.concordia.ca\/explorations\/wp-json\/wp\/v2\/license?post=254"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}