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6: Race and Human Variation

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    130059
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    Michael B. C. Rivera, Ph.D., University of Cambridge

    Learning Objectives
    • Review the illustrious and (at times) troubling history of “race” concepts.
    • Recognize human diversity and evolution as the thematic roots of our discipline.
    • Critique earlier “race” concepts based on overall human diversity being lower compared to other species and human genetic variation being greater within a population than between populations.
    • Explain how biological variation in humans is distributed clinally and in accordance with both isolation-by-distance and Out-of-Africa models.
    • Identify phenotypic traits that reflect selective and neutral evolution.
    • Relate a more nuanced view of human variation with today’s ongoing bioanthropological research, implications for biomedical studies, applications in forensic anthropology, and sociopolitical/economic concerns.

    Humans exhibit biological diversity. Cognitively, humans also have a natural desire to categorize objects and other humans in order to make sense of the world around them. Since the birth of the discipline of biological anthropology, we have been interested in studying how humans vary biologically and what the sources of this variation are. Before we tackle these big problems, this first begs the question: Why should we study human diversity?

    There are certainly academic reasons for studying human diversity. First, it is highly interesting and important to consider the evolution of our species and how our biological variation may be similar to (or different from) that of other species of animals (e.g., other primates and apes). Such investigation can give us clues as to how unique we are as a biological organism in relation to the rest of the animal kingdom. Second, anthropologists study modern human diversity to understand how different biological traits developed over evolutionary time. If we are able to grasp the evolutionary processes that produce and affect diversity, we can make more accurate inferences about evolution and adaptation among our hominin ancestors, complementing our study of fossil evidence and the archaeological record. Third, as will be discussed in more detail later on, it is important to consider that biological variation among humans has biomedical, forensic, and sociopolitical implications. For these reasons, the study of human variation and evolution has formed the basis of anthropological inquiry for centuries and continues to be a major source of intrigue and inspiration for scientific research conducted today.

    An even more important role of the biological anthropologist is to improve public understanding of human evolution and diversity, outside of academic circles. Terms such as race and ethnicity are used in everyday conversations and in formal settings within and outside academia. The division of humankind into smaller, discrete categories is a regular occurrence in day-to-day life. This can be seen regularly when governments acquire census data with a heading like “geographic origin” or “ethnicity.” Furthermore, such checkboxes and drop-down lists are commonly seen as part of the identifying information required for surveys and job applications.

    According to the Oxford English Dictionary (2018), race is a term that should be used to describe one or more of the following:

    • a major division of the human species based on particular physical characteristics;
    • the biological origin of a group of people, or ancestry;
    • the fact or condition of belonging to a racial division or group, or the social qualities associated with this;
    • a group of people sharing the same culture and language;
    • any group of people or things with a common feature or features;
    • a population within a species that is distinct in some way, especially a subspecies.

    So many various definitions for one word already suggests that perhaps the concepts or meanings behind biological diversity are complicated. Even though the terms race and ethnicity are used often in commonplace settings, there is no consensus among biological anthropologists as to what races are, whether they even exist, and, if they do, how the term should be applied to the human species meaningfully. If biological anthropologists cannot reach a consensus on how to view human diversity, how can we possibly expect there to be a clear perspective on the nature and causes of biological variation outside of scientific academia? Ideas about ethnicity that people hold have huge social and political impacts, and notions of race have been part of the motivation behind various forms of racism and prejudice today, as well as many wars and genocides throughout history. This is how the role of the biological anthropologist becomes crucial in the public sphere, as we may be able to debunk myths surrounding human diversity and shed light on how human variation is actually distributed worldwide for the non-anthropologists around us (Figure 13.1). Recent work in anthropological genetics has revealed the similarities amongst humans on a molecular level and the relatively few differences that exist between populations that one might be tempted to see as significantly distinctive.

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    Figure 13.1 Humans are biologically and culturally diverse. (Top left: Hadzabe members in Tanzania; top right: Inuit family in traditional seal and caribou clothing; bottom left: Andean man in traditional dress in Peru; bottom right: Dr. Jane Goodall.)

    Science communication and education that centers upon race and our species’ variation is interesting and important. Throughout this chapter, I will highlight how humans cannot actually be divided into discrete “races,” because most traits instead vary on a continuous basis and human biology is, in fact, very homogenous compared to the greater genetic variation we observe in other closely related species. The reason we know this now is thanks to technological developments that have taken place over the last 50 or so years. Molecular anthropology, or anthropological genetics, revolutionized and continues to add new layers to our understanding of human biological diversity and the evolutionary processes that gave rise to the patterns of variation we observe in contemporary populations. The study of human variation has not always been unbiased, and thinkers and scientists have always worked in their particular sociohistorical context. For this reason, this chapter opens with a brief overview of race concepts throughout history, many of which relied on unethical and unscientific notions about different human groups.

    About the Author

    Michael B. C. Rivera

    University of Cambridge, mbcr2@alumni.cam.ac.uk

    The Arch and Anth Podcast, archandanthpodcast@gmail.com

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    Michael B. C. Rivera

    Michael B. C. Rivera is a biological anthropologist and human bioarchaeologist, studying the transition into agriculture in coastal environments. His recently completed doctoral thesis brought together human skeletal biology, palaeopathology, and prehistoric archaeology to investigate the lives of ancient people on the northeastern European coastline. Being from Hong Kong and a student of human biological variation, Michael is also an advocate for greater inclusion, diversity, and equality in academia. Additionally, as a believer in the value of science communication, and of the value of the discipline to greater society, he launched The Arch and Anth Podcast in May 2019, which disseminates scientific knowledge in a fun, educational, and informal interview-style audio format.

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    Figure Attributions

    Figure 13.1a Tanzania – Hadzabe hunter (14533536392) by A_Peach from Berlin, Germany, is used under a CC BY 2.0 License.

    Figure 13.1b Inuit-Kleidung 1 by Ansgar Walk is used under a CC BY-SA 3.0 License.

    Figure 13.1c Andean Man by Cacophony is used under a CC BY-SA 4.0 License.

    Figure 13.1d Jane Goodall GM byFloatjon is used under a CC BY-SA 3.0 License.

    Figure 13.2 Egyptian races Drawing (1772-1846) by an unknown artist after a mural of the tomb of Seti I, Copy by Heinrich von Minutoli (1820), is in the public domain.

    Figure 13.3 Naturalishistoria from the front page of Pliny the Elder’s Naturalis Historia is in the public domain.

    Figure 13.4 Great Chain of Being 2 by Didacus Valades (Diego Valades) is in the public domain.

    Figure 13.5 Carl von Linné by Alexander Roslin artist QS:P170,Q315102 is in the public domain.

    Figure 13.6 Discovery of the Mississippi by William Henry Powell artist QS:P170,Q3568696 (photograph courtesy Architect of the Capitol) is in the public domain.

    Figure 13.7 Blumenbach’s five races by Johann Friedrich Blumenbach is in the public domain.

    Figure 13.8 (Ales Hrdlicka) SIA2009-4246 by Unknown photographer is in the public domain.

    Figure 13.9 Eugenics congress logo scanned from Harry H. Laughlin, The Second International Exhibition of Eugenics held September 22 to October 22, 1921, is in the public domain.

    Figure 13.10 Dobzhansky no Brasil em 1943 by Unknown photographer is in the public domain.

    Figure 13.11 Julian Huxley 1-2 by Unknown photographer is in the public domain.

    Figure 13.12 Skin color by S25454541 is used under a CC BY-SA 4.0 License.

    Figure 13.13a Map of blood group a by Muntuwandi at en.Wikipedia is used under a CC BY-SA 3.0 License.

    Figure 13.13b Map of blood group b by Muntuwandi at en.Wikipedia is used under a CC BY-SA 3.0 License.

    Figure 13.13c Map of blood group o Based on diagrams from anthro.palomar.edu/vary/vary_3.htm reproduced from A. E. Mourant et.al., The Distribution of the Human Blood Groups and Other Polymorphisms, 2nd ed. (1976) is used under a CC BY-SA 3.0 License.

    Figure 13.14 Sub-Saharan-Africa by Ezeu has been designated to the public domain (CC0).

    Figure 13.15 Bottleneck effect by Tsaneda is used under a CC BY 3.0 License.

    Figure 13.16 Chimpanzee IV (13968482163) by Chi King is used under a CC BY 2.0 License.

    Figure 13.17 Human skulls by 22Kartika is used under a CC BY-SA 3.0 License.

    Figure 13.18 Bony labyrinth by Selket (5 February 2007, UTC) has been designated to the public domain (CC0).

    Figure 13.19 Forensic Anthropology Lab by Pp391 is used under a CC BY-SA 3.0 License.

    Figure 13.20 Michael B. C. Rivera in Hong Kong original to Explorations: An Open Invitation to Biological Anthropology is under a CC BY-NC 4.0 License.


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