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6: Race and Human Variation

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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.

    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,

    The Arch and Anth Podcast,

    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.


    Antrosio, Jason. 2011. “‘Race Reconciled’: Race Isn’t Skin Color, Biology, or Genetics.” Living Anthropologically Website.

    Beals, Kenneth L., Courtland L. Smith, Stephen M. Dodd, J. Lawrence Angel, Este Armstrong, Bennett Blumenberg, Fakhry G. Girgis, et al. 1984. “Brain Size, Cranial Morphology, Climate, and Time Machines [and Comments and Reply].” Current Anthropology 25 (3): 301‒330.

    Betti, Lia, François Balloux, William Amos, Tsunehiko Hanihara, and Andrea Manica. 2008. “Distance from Africa, Not Climate, Explains Within-Population Phenotypic Diversity in Humans.” Proceedings of the Royal Society B: Biological Sciences 276 (Issue 165B): 809‒814. doi:10.1098/rspb.2008.1563.

    Betti, Lia, François Balloux, Tsunehiko Hanihara, and Andrea Manica. 2010. “The Relative Role of Drift and Selection in Shaping the Human Skull.” American Journal of Physical Anthropology 141 (1): 76‒82. doi:10.1002/ajpa.21115.

    Betti, Lia, Noreen von Cramon-Taubadel, Andrea Manica, and Stephen J. Lycett. 2013. “Global Geometric Morphometric Analyses of the Human Pelvis Reveal Substantial Neutral Population History Effects, Even across Sexes.” PloS ONE 8 (2): e55909. doi:10.1371/journal.pone.0055909.

    ———. 2014. “The Interaction of Neutral Evolutionary Processes with Climatically Driven Adaptive Changes in the 3D Shape of the Human Os Coxae.” Journal of Human Evolution 73 (August): 64‒74. doi:10.1016/j.jhevol.2014.02.021.

    Boas, Franz. 1931. “Race and Progress.” Science 74 (1905): 1‒8.

    Bowden, Rory, Tammie S. MacFie, Simon Myers, Garrett Hellenthal, Eric Nerrienet, Ronald E. Bontrop, Colin Freeman, Peter Donnelly, and Nicholas I. Mundy. 2012. “Genomic Tools for Evolution and Conservation in the Chimpanzee: Pan troglodytes ellioti Is a Genetically Distinct Population.” PLoS Genetics 8 (3): e1002504. doi:10.1371/journal.pgen.1002504.

    Gerbault, Pascale, Anke Liebert, Yuval Itan, Adam Powell, Mathias Currat, Joachim Burger, Dallas M. Swallow, and Mark G. Thomas. 2011. “Evolution of Lactase Persistence: An Example of Human Niche Construction.” Philosophical Transactions of the Royal Society B 366 (1566): 863‒877. doi:10.1098/rstb.2010.0268.

    Hooton, Earnest A. 1936. “Plain Statements about Race.” Science 83 (2161): 511‒513.

    Hrdlička, Aleš. 1918. “Physical Anthropology: Its Scope and Aims; Its History and Present Status in America. A: Physical Anthropology; Its Scopes and Aims.” American Journal of Physical Anthropology 1 (1): 3‒23.

    Huxley, Julian. 1942. Evolution: The Modern Synthesis. London: Allen and Unwin.

    Ingram, Catherine J. E., Charlotte A. Mulcare, Yuval Itan, Mark G. Thomas, and Dallas M. Swallow. 2009. “Lactose Digestion and the Evolutionary Genetics of Lactase Persistence.” Human Genetics 124 (6): 579‒591. doi:10.1007/s00439-008-0593-6.

    Jablonski, Nina G. 2004. “The Evolution of Human Skin and Skin Color.” Annual Review of Anthropology 33 (1): 585‒623. doi:10.1146/annurev.anthro.33.070203.143955.

    Jablonski, Nina G., and George Chaplin. 2000. “The Evolution of Human Skin Coloration.” Journal of Human Evolution 39 (1): 57‒106. doi:10.1006/jhev.2000.0403.

    Kronenberg, Zev N., Ian T. Fiddes, David Gordon, Shwetha Murali, Stuart Cantsilieris, Olivia S. Meyerson, Jason G. Underwood, et al. 2018. “High-Resolution Comparative Analysis of Great Ape Genomes.” Science 360 (6393): eaar6343. doi:10.1126/science.aar6343.

    Lewontin, Richard. 1972. “The Apportionment of Human Diversity.” Evolutionary Biology 6: 381‒398. Eds. Dobzhansky, Theodosius, Hecht, Max K., Steere, William C. Springer, New York, NY

    Linnaeus, Carl. 1758. Systema Naturae.

    Liu, Hua, Franck Prugnolle, Andrea Manica, and François Balloux. 2006. “A Geographically Explicit Genetic Model of Worldwide Human-Settlement History.” American Journal of Human Genetics 79 (2): 230‒237.

    Livingstone, Frank B. 1962. “On the Nonexistence of Human Races.” Current Anthropology 3 (3): 279‒281.

    Long, Jeffery C., and Kittles, Rick A. 2003. “Human Genetic Diversity and the Nonexistence of Biological Races.” Human Biology 75 (4): 449‒471.

    Luzzatto, Lucio. 2012. “Sickle Cell Anaemia and Malaria.” Mediterranean Journal of Hematology and Infectious Diseases 4 (1). doi:10.4084/MJHID.2012.065.

    Manica, Andrea, William Amos, François Balloux, and Tsunehiko Hanihara. 2007. “The Effect of Ancient Population Bottlenecks on Human Phenotypic Variation.” Nature 448 (7151): 346‒348. doi:10.1038/nature05951.

    Mourant, A. E., Ada C. Kopeć, and Kazimiera Domaniewska-Sobczak. 1976. The Distribution of the Human Blood Groups and Other Polymorphisms. 2nd edition. Oxford: Oxford University Press.

    Morton, Samuel George. 1839.Crania Americana, or, A comparative view of the skulls of various aboriginal nations of North and South America. Philadelphia: J. Dobson.

    National Research Council (U.S.) Committee on Human Genome Diversity. 1997. Evaluating Human Genetic Diversity. Washington, D.C.: National Academies Press

    Ousley, Stephen D., Richard L. Jantz, and Donna Freid. 2009. “Understanding Race and Human Variation: Why Forensic Anthropologists Are Good at Identifying Race.” American Journal of Physical Anthropology 139 (1): 68‒76. doi:10.1002/ajpa.21006.

    Oxford English Dictionary. 2018. 3rd edition. Oxford: Oxford University Press.

    Ponce de León, Marcia S., Toetik Koesbardiati, John David Weissmann, Marco Millela, Carlos S. Reyna-Blanco, Gen Suwa, Osamu Kondo, Anna-Sapfo Malaspinas, Tim D. White, and Christoph P. E. Zollikofer. 2018. “Human Bony Labyrinth Is an Indicator of Population History and Dispersal from Africa.” Proceedings of the National Academy of Sciences 115 (16): 4128‒4133. doi:10.1073/pnas.1808125115.

    Prado-Martinez, Javier, Peter H. Sudmant, Jeffrey M. Kidd, Heng Li, Joanna L Kelley, Belen Lorente-Galdos, Krishna R. Veeramah, et al. 2013. “Great Ape Genetic Diversity and Population History.” Nature 499 (7459): 471–475. doi:10.1038/nature12228.

    Prugnolle, Franck, Andrea Manica, and François Balloux. 2005. “Geography Predicts Neutral Genetic Diversity of Human Populations.” Current Biology 15 (5): 159‒160.

    Rathmann, Hannes, Hugo Reyes-Centeno, Silvia Ghirotto, Nicole Creanza, Tsunehiko Hanihara, and Katerina Harvati. 2017. “Reconstructing Human Population History from Dental Phenotypes.” Scientific Reports 7: 12495. doi:10.1038/s41598-017-12621-y.

    Relethford, John H. 2001. “Global Analysis of Regional Differences in Craniometric Diversity and Population Substructure.” Human Biology 73 (5): 629‒636. doi:10.1353/hub.2001.0073.

    ———. 2002. “Apportionment of Global Human Genetic Diversity Based on Craniometrics and Skin Color.” American Journal of Physical Anthropology 118 (4): 393‒398. doi:10.1002/ajpa.10079.

    ———. 2004. “Global Patterns of Isolation by Distance Based on Genetic and Morphological Data.” Human Biology 76 (4): 499‒513. doi:10.1353/hub.2004.0060.

    ———. 2009. “Race and Global Patterns of Phenotypic Variation.” American Journal of Physical Anthropology 139 (1): 16‒22. doi:10.1002/ajpa.20900.

    Rosenberg, Noah A., Saurabh Mahajan, Sohini Ramachandran, Chengfeng Zhao, Jonathan K. Pritchard, and Marcus W. Feldman. 2005. “Clines, Clusters, and the Effect of Study Design on the Inference of Human Population Structure.” PLoS Genetics 1 (6): e70. doi:10.1371 /journal.pgen.0010070.

    Rosenberg, Noah A., Jonathan K. Pritchard, James L. Weber, Howard M. Cann, Kenneth K. Kidd, Lev A. Zhivotovsky, and Marcus W. Feldman. 2002. “Genetic Structure of Human Populations.” Science 298 (5602): 2381‒2385.

    Sauer, Norman J. 1992. “Forensic Anthropology and the Concept of Race: If Races Don’t Exist, Why Are Forensic Anthropologists So Good at Identifying Them?” Social Science and Medicine 34 (2): 107‒111. doi:10.1016/0277-9536(92)90086-6.

    Staes, Nicky, Chet C. Sherwood, Katharine Wright, Marc de Manuel, Elaine E. Guevara, Tomas Marques-Bonet, Michael Krützen, et al. 2017. “FOXP2 Variation in Great Ape Populations Offers Insight into the Evolution of Communication Skills.” Scientific Reports 7 (1): 1‒10. doi:10.1038/s41598-017-16844-x.

    von Cramon-Taubadel, Noreen, and Stephen J. Lycett. 2008. “Brief Communication: Human Cranial Variation Fits Iterative Founder Effect Model with African Origin.” American Journal of Physical Anthropology 136 (1): 108‒113. doi:10.1002/ajpa.20775.

    Warren, Kerryn A. 2018. “AAPA Name Change.” Bone and Evolution, April 4.

    Weiss, Kenneth M., and Jeffrey C. Long. 2009. “Non-Darwinian Estimation: My Ancestors, My Genes’ Ancestors.” Genome Research 19: 703‒710. doi:10.1101/gr.076539.108.19.

    Wise, Tim. 2010. Colorblind: The Rise of Post-Racial Politics and the Retreat from Racial Equity. San Francisco: City Lights.

    Yudell, Michael, Dorothy Roberts, Rob DeSalle, and Sarah Tishkoff. 2016. “Taking Race out of Human Genetics.” Science 351 (6273): 564‒565. doi:10.1126/science.aac4951.

    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 reproduced from A. E. Mourant, 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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