Explorations: An Open Invitation to Biological Anthropology

Citation

Shook, B., Braff, L., Nelson, K., & Aguilera, K. (Eds.). (2023). Explorations: An Open Invitation to Biological Anthropology (2nd ed.). American Anthropological Association. Free official edition: https://explorations.americananthro.org/

Chapter Summary

The book has seventeen chapters and four appendices, each written by a different specialist or team and edited by the four editors. The preface describes the plan: Chapters 1–4 lay the foundations (the discipline, evolutionary thought, genetics and the forces of evolution); Chapters 5–8 deal with the living primates, the fossil record and primate evolution; Chapters 9–12 follow the hominins to modern Homo sapiens; and Chapters 13–17 take up human variation, forensic anthropology, health and the politics of heredity. Every chapter opens with learning objectives and closes with review questions and a list of key terms.

Chapters 1–2: Introduction to Biological Anthropology; A History of Evolutionary Thought

Chapter 1 places biological anthropology among the discipline's subfields (cultural, linguistic, applied, archaeology and biological), presents the anthropological approaches of holism, comparison, dynamism and fieldwork, and surveys the subfields of the biological side: primatology, paleoanthropology, molecular anthropology, bioarchaeology, forensic anthropology and human biology. It then explains the scientific method, the difference between hypotheses, theories and laws, and how science differs from faith as a way of knowing. Chapter 2, new in this edition, traces evolutionary ideas from ancient and medieval thinkers through the Western European tradition to Darwin and Wallace, what Darwin lacked (an account of heredity, supplied by Mendel), and the Modern Synthesis. It also covers common misconceptions, how evolution is taught around the world, and whether humans are still evolving.

Chapters 3–4: Molecular Biology and Genetics; Forces of Evolution

Chapter 3 builds the biology that later chapters assume: cells and molecules, DNA structure, replication and cell division, protein synthesis, Mendelian inheritance (with the ABO blood groups as the worked example), polygenic traits, genomics, epigenetics and genetic testing. Chapter 4 turns genes into population change, with mutation, genetic drift, gene flow and natural selection, the Hardy-Weinberg equilibrium, speciation, and the link from micro- to macroevolution. Special topics include neurofibromatosis, sickle cell anemia and the calculation of Hardy-Weinberg frequencies.

Chapters 5–6: Meet the Living Primates; Primate Ecology and Behavior

Chapter 5 explains how primates are classified (grades versus clades), which traits define the order, and the main groups from lemurs and lorises through tarsiers and New World monkeys to Old World monkeys, apes and humans. Chapter 6 moves to diet, community ecology, group living, reproductive strategies, communication and the evidence for cultural traditions in chimpanzees and macaques. Its special topics cover women in primatology and decolonizing primatology.

Chapters 7–8: Stones and Bones: Studying the Fossil Record; Primate Evolution

Chapter 7 covers how fossils form (taphonomy, types of fossils), relative and chronometric dating methods, and environmental reconstruction. Chapter 8 uses these tools to follow primates from competing hypotheses about their origins (arboreal, visual predation, angiosperm coevolution) through plesiadapiforms, the first true primates and the anthropoids to the apes of the Miocene.

Chapters 9–10: Early Hominins; Early Members of the Genus Homo

Chapter 9 defines hominins and links their evolution to paleoenvironmental hypotheses, bipedalism, dentition and the earliest stone tools, then reviews Sahelanthropus, Orrorin, Ardipithecus, Australopithecus and Paranthropus. Chapter 10 defines the genus Homo, discusses Pleistocene climate change, and treats Homo habilis and Homo erectus, including their anatomy, tools, diet, fire and migration out of Africa.

Chapters 11–12: Archaic Homo; Modern Homo sapiens

Chapter 11 sets aside the "caveman" stereotype to describe archaic Homo sapiens, Neanderthal anatomy, culture and disappearance, the Denisovans, and the puzzling Homo naledi and Homo floresiensis. Chapter 12 defines modernity in skeletal and behavioral terms, follows the spread of our species across Africa, to Australia, Europe and the Americas, and then examines the origins and consequences of agriculture.

Chapters 13–14: Race and Human Variation; Human Variation: An Adaptive Significance Approach

Chapter 13 reviews the history of "race" concepts and shows why contemporary data (nonconcordant traits, clinal variation, greater variation within than between groups) do not support them. Chapter 14 distinguishes adjustments from adaptations in coping with stressors, with examples including skin tone, high-altitude populations and the sickle-cell trait.

Chapters 15–17: Forensic Anthropology; Contemporary Topics: Human Biology and Health; Social and Biopolitical Dimensions of Evolutionary Thinking

Chapter 15 sets out the questions of skeletal analysis (is it bone, is it human, how many individuals, the biological profile, trauma, taphonomy) and the ethics of working with human remains; it carries a content warning. Chapter 16 applies evolution to health: diet and disease before agriculture, epidemiological transitions, obesity, cardiovascular disease, cancer, stress and the syndemic framing of COVID-19. Chapter 17 argues that evolution operates at multiple levels, examines the biopolitics of heredity, and criticizes adaptationism.

Appendices A–D

The appendices cover osteology, primate conservation, human behavioral ecology and ancient DNA.

Key Concepts

Chapters 1–4: Foundations

• Holism and comparison: anthropology's habit of studying humans in all their aspects and by comparing populations and species.
• Modern Synthesis: the combination of Mendelian genetics with Darwinian natural selection into a unified theory.
• Forces of evolution: mutation, genetic drift, gene flow and natural selection as the processes that change allele frequencies.
• Hardy-Weinberg equilibrium: the expected genotype frequencies in a population when no evolutionary forces act.

Chapters 5–8: Primates and the Fossil Record

• Grades and clades: two ways of grouping taxa, by shared level of organization or by common ancestry.
• Derived and ancestral traits: the distinction used to classify primates and, later, hominins.
• Chronometric and relative dating: methods that give numerical ages and methods that only order finds in time.
• Taphonomy: the study of what happens to an organism between death and discovery.

Chapters 9–12: Hominin Evolution

• Bipedalism: the anatomical changes associated with walking on two legs, treated as the key early hominin adaptation.
• Paleoenvironmental hypotheses: the savannah, turnover pulse and variability selection explanations for hominin change.
• Archaic Homo sapiens: the Middle Pleistocene groups, including Neanderthals and Denisovans, between early Homo and modern humans.
• Behavioral modernity: the set of behavioral signs, alongside skeletal traits, used to define modern Homo sapiens.

Chapters 13–17: Variation, Health and Society

• Clinal variation: gradual geographic change in traits, which undercuts discrete racial categories.
• Adjustment versus adaptation: nongenetic coping versus genetically based change in response to stress.
• Biological profile: the estimate of age, sex, ancestry and stature from a skeleton in forensic work.
• Syndemic and mismatch: interacting health crises, and the gap between evolved biology and modern lifestyles.
• Biopolitics of heredity: the social and political uses of ideas about genes and ancestry.

Critical Analysis

Strengths

• Specialist authors, consistent format. Each chapter is written by a researcher or teacher in the area, from primatologists to forensic anthropologists, yet the shared structure of learning objectives, special topics, "dig deeper" boxes, review questions and key terms makes the volume read as one book.
• A clear teaching design. The preface says chapters were shortened to 8,000–10,000 words and an instructors' guide shows how to reorder, drop or adapt chapters. The editors also describe student reviewers' input and accessibility reviews.
• Race is treated head-on. A full chapter reviews the history of race concepts and the genetic evidence on human variation, and a further chapter on the biopolitics of heredity and the limits of adaptationism pushes students to question simple genetic explanations.
• Applications and context. Forensic anthropology, health and disease, primate conservation and the ethics of studying human remains appear as chapters or appendices, rather than as asides.
• Free and adaptable. The Creative Commons license (attribution, non-commercial) allows reuse and adaptation, and the book can be read online, downloaded or ordered in print.

Limitations

• Uneven voice and depth. Because the chapters have different authors, the level of detail varies, and some open with personal anecdotes while others do not.
• Chapters depend on each other. Later chapters refer back to Chapters 2–4, so selecting a few chapters for a short course needs planning.
• Narrow scope outside biology. Archaeology and bioarchaeology are mostly left to other open books, as the preface points out, and the forensic methods in Chapter 15 are described as specific to the United States.
• Species detail is delegated to tables. The hominin chapters lean on "Hominin Species Summaries" for specimen-level facts; readers who want site-by-site argument will need a reference such as Klein's volume.

Where It Fits in the Course

Within this course list, Explorations is a free alternative to the commercial introductory textbooks in biological anthropology, such as Stanford, Allen and Antón's Biological Anthropology and Larsen's Our Origins. All follow roughly the same sequence from evolutionary mechanisms to primates, hominins and human variation, so choose among them on cost, voice and the presence of extras such as a lab manual (Explorations has a separate lab and activities manual).

Bernard Wood's Human Evolution: A Very Short Introduction is a brief account of the fossil evidence, useful as a quick companion to Chapters 9–12. For more depth, Lewin and Foley's Principles of Human Evolution treats the human lineage as an instance of general evolutionary and ecological theory and assumes an introductory course, and Klein's The Human Career is a large, densely referenced survey of the fossil and archaeological record that works as a reference after Explorations.

How to Use This Book

The book is for first-year and second-year students in an introductory biological anthropology course. No previous biology is assumed, and Chapters 3 and 4 teach the genetics from scratch.

A practical plan:

• Core: Chapters 1–4 first, then 5, 7, 9, 10, 11 and 12 in order. These give the evolutionary frame and the main hominin story.
• Add as needed: Chapters 6 and 8 for primate behavior and primate origins; Chapter 13 before or after Chapter 12, since it discusses human variation and can stand alone; Chapters 14–17 as units on adaptation, forensic work, health and the history of ideas about heredity.
• Appendices: Appendix A is a useful reference for osteology before Chapter 15; Appendix D complements Chapters 11 and 12.

Read the learning objectives before each chapter, answer the review questions afterwards, and use the key-term lists for revision. Allow extra time for the genetics chapters (3 and 4) and for the species-heavy Chapters 9–11. Readers who want a shorter path can combine Chapters 1–4 with Wood's short book.

Edition and Sources

This guide describes the second edition (July 2023), published by the American Anthropological Association under a Creative Commons Attribution-NonCommercial 4.0 license, with the free ebook at https://explorations.americananthro.org/ as the official version. It is based on the free official edition, including the preface and instructors' guide, the learning objectives, section headings, special topics, review questions and key-term lists of all seventeen chapters and four appendices, and the opening and closing sections of each.