The Invisible History of the Human Race

by Christine Kenneally

This has implications for the genetic databases: Even though sharing a common segment with someone doesn’t necessarily mean you have inherited that block from a relatively recent common ancestor, it is often the case that when genetic genealogy companies help customers with shared DNA hook their genealogical trees together, they do find a distant shared cousin from, say, six generations ago. What is the likelihood in this case that the shared block comes not from a shared fourth-great-grandparent but in fact from someone much further back along a different route through the genealogical tree? According to Ralph, the chance of two people sharing a block from a sixth-generation ancestor is close to one, so the chance of the shared block coming from an identified ancestor is pretty high. Yet it is still possible that those two people also share a block that doesn’t come from that ancestor. “If the known ancestor was Charlemagne,” Ralph explained, “the chance that you both inherited blocks from him is pretty small, so the block is probably not from him, especially given the huge number of unknown relatives you share from the time of Charlemagne.”

  contributed nothing to you genetically: The effect was first pointed out to Patterson by Oxford professor Jotun Hein in 2004. See D. L. Rohde, S. Olson, and J. T. Chang, “Modelling the Recent Common Ancestry of All Living Humans,” Nature 431, no. 7008 (2004): 562–66.

  “Northern Italy had the tradition”: Quotes from Guido Tabellini in this chapter are from my interview with him.

  Chapter 11: The Politics of DNA

  “an intimate and loving relationship”: G. Wood, “The Sally Hemings Case,” Barbara Chase-Riboud, reply by Gordon S Wood, New York Review of Books, June 12, 1997, available at http://www.nybooks.com/articles/archives/1997/jun/12/the-sally-hemings-case/. Note that in a May 2013 New York Review of Books article, Wood praised Gordon-Reed’s acute and correct analysis.

  match the Hemings Y: E. A. Foster, et al., “Jefferson Fathered Slave’s Last Child,” Nature 396, no. 6707 (1998): 27–28.

  deny the Jefferson/Hemings link: E. S. Lander and J. J. Ellis, “Founding Father,” Nature 396, no. 6707 (1998): 13–14.

  “suggests the strong likelihood”: D. P. Jordan, Statement on the TJMF Research Committee Report on Thomas Jefferson and Sally Hemings, available at http://www.monticello.org/site/plantation-and-slavery/report-research

  -committee-thomas-jefferson-and-sally-hemings.

  “veins was Thomas Jefferson’s”: M. Hendricks, “A Daughter’s Dedication,” Johns Hopkins Magazine, September 1999, available at http://pages.jh

  .edu/~jhumag/0999web/roots.html.

  stories and the DNA evidence: S. R. Williams, “Genetic Genealogy: The Woodson Family’s Experience,” Culture, Medicine and Psychiatry 29, no. 2 (2005): 225–52; and personal communciation.

  “They matched so well”: Unless otherwise cited, quotes from Sloan Williams in this chapter are from my interviews with her.

  “They were extremely suspicious”: S. R. Williams, “Genetic Genealogy: The Woodson Family’s Experience,” Culture, Medicine and Psychiatry 29,

  no. 2 (2005) 226.

  black—were as well: CeCe Moore of YourGeneticGenealogist.com currently runs an autosomal DNA project to gather DNA from descendants of Madison Hemings (as well as descendants of Eston and the other Hemings children) in order to try to match it against descendants of the known Jefferson lineage. She also accepts DNA from other nonlineal relatives of the Jefferson and Hemings families.

  “results are unexpected or undesired”: D. A. Bolnick, et al., “The Science and Business of Genetic Ancestry Testing,” Science 318, no. 5849 (2007): 399.

  “general and the scientific communities”: C. D. Royal, et al., “Inferring Genetic Ancestry: Opportunities, Challenges, and Implications,” American Journal of Human Genetics 86, no. 5 (2010): 661–73.

  “more problems than it solves”: C. Elliott and P. Brodwin, “Identity and Genetic Ancestry Tracing,” British Medical Journal 325, no. 7378 (2002): 1469.

  few scientists would disagree: J. Marks, “Contemporary Bio-Anthropology,” Anthropology Today 18, no. 4 (2002)): 3, 5, 7; and J. Marks, “‘We’re Going to Tell These People Who They Really Are’: Science and Relatedness,” in Relative Values: Reconfiguring Kinship Studies, ed. S. Franklin and S. McKinnon (Durham and London: Duke University Press, 2001), pp. 355–83.

  “Africa and Africans as primordial”: K. TallBear, “Narratives of Race and Indigeneity in the Genographic Project,” The Journal of Law, Medicine & Ethics 35, no. 3, 412–424.

  “political agenda of science haters”: C. Tuniz, R. Gillespie, and C. Jones, The Bone Readers (Crows Nest: Allen & Unwin, 2009), 195

  differently shaped skulls: L. Betti, et al., “The Relative Role of Drift and Selection in Shaping the Human Skull,” American Journal of Physical Anthropology 141, no. 1 (2010): 76–82.

  no such thing as biological race: Lewontin is not the only researcher who made this case, yet while others made it before him, he is most often popularly associated with this argument today.

  “Human races and populations are remarkably similar”: R. C. Lewontin, “The Apportionment of Human Diversity,” Evolutionary Biology 6 (1972): 381–98. For a recent essay about Lewontin’s views on race and ancestry see R. Lewontin, “Confusions About Human Races,” Is Race “Real”? June 7, 2006, available at http://raceandgenomics.ssrc.org/Lewontin/

  “two random individuals”: D. Witherspoon, “Genetic Similarities Within and Between Human Populations,” Genetics, May 2007; 176 (1): 351.

  the picture changes: This was first pointed out in A. W. Edwards, “Human Genetic Diversity: Lewontin’s Fallacy,” BioEssays 25, no. 8 (2003): 798–801. Also see N. Risch, et al., “Categorization of Humans in Biomedical Research: Genes, Race and Disease,” Genome Biology 3, no. 7 (2002): 1–12.

  than from a distant one: D. Witherspoon, “Genetic Similarities Within and Between Human Populations,” Genetics, May 2007; 176 (1): 351.

  genetics as a solution to disease: L. Braun, “Reifying Human Difference: The Debate on Genetics, Race, and Health,” International Journal of Health Services 36, no. 3 (2006): 557–73.

  medical utility of “race”: A. M. Leroi, “A Family Tree in Every Gene,” Journal of Genetics 84, no. 1 (2005): 3–6.

  “clear benefits for public health”: J. Stevens, “Eve Is from Adam’s Rib, the Earth Is Flat, and Races Come from Genes,” in Is Race “Real”? June 7, 2006, available at http://raceandgenomics.ssrc.org/Stevens/.

  “data-rich scientists”: Quotes from Eran Elhaik in this chapter are from my interviews with him.

  “You cannot do it for every population”: A different study found that Indian castes seemed to differ in the relative proportion of northern and southern Indian DNA in their genome. D. Reich, et al., “Reconstructing Indian Population History,” Nature 461, no. 7263 (2009): 489–94.

  Ancestry does not work that way: Other analyses have shown that the racial/ethnic self-identification of people who were sorted into clusters based on genomic markers agreed with the clustering. See, for example, N. Risch, et al., “Categorization of Humans in Biomedical Research: Genes, Race and Disease,” Genome Biology 3, no. 7 (2002): 1–12.

  a survey conducted by Wendy Roth: W. D. Roth and B. Ivemark, “‘Not Everybody Knows That I’m Actually Black’: The Effects of DNA Ancestry Testing on Racial and Ethnic Boundaries,” presented at the American Sociological Association Annual Meeting Atlanta, August 14–17, 2010.

  “general level of ignorance”: Unless otherwise cited, quotes from Wendy Roth in this chapter are from my interviews with her.

  to include the new information: Their identification depended on a number of factors, including their level of education, how distant they felt from the group in question, whether they looked physically as if they belonged to one group and not another, and how their family identified itself.

  “integrating the contributing factors”: Quotes
from Jennifer Wagner in this chapter are from my interviews with her.

  “the study of peas or fruit flies”: N. G. Jablonski, M. Shriver, and H. Gates, “Using Genetics and Genealogy to Teach Evolution and Human Diversity,” National Evolutionary Synthesis Center, Catalysis Meeting, available at https://www.nescent.org/science/awards_summary.php?id=321.

  Chapter 12: The History of the World

  intentional engraving were discovered: P.-J. Texier, et al., “A Howiesons Poort Tradition of Engraving Ostrich Eggshell Containers Dated to 60,000 Years Ago at Diepkloof Rock Shelter, South Africa,” Proceedings of the National Academy of Sciences 107, no. 14 (2010): 6180–85.

  more than 100,000years ago: T. F. Strasser, et al., “Dating Palaeolithic Sites in Southwestern Crete, Greece,” Journal of Quaternary Science 26, no. 5 (2011): 553–60.

  ocher processing: C. S. Henshilwood, et al., “A 100,000-Year-Old Ochre-Processing Workshop at Blombos Cave, South Africa,” Science 334, no. 6053 (2011): 219–22.

  their stone tools using heat: V. Mourre, P. Villa, and C. S. Henshilwood, “Early Use of Pressure Flaking on Lithic Artifacts at Blombos Cave, South Africa,” Science 330, no. 6004 (2010): 659–62.

  perhaps not much more than one thousand: The number of individuals in an ancestral population is usually considerably greater than the number of individuals who reproduce, known as the effective population size. The estimate of 1,000-2,500 individuals is the effective population size. See B. Henn, et al. “The Great Human Expansion,” Proceedings of the National Academy of Sciences 109, 44 (2012): 17758–17764.

  “that happened a long time ago”: Quotes from Marcus Feldman in this chapter are from my interview with him.

  skating on ice: F. Formenti and A. E. Minetti, “The First Humans Travelling on Ice: An Energy-Saving Strategy?” Biological Journal of the Linnean Society 93, no. 1 (2008): 1–7.

  Pacific coastline and then eastward: J. A. Raff and D. A. Bolnick, “Genetic Roots of the First Americans,” Nature 506, no. 7487 (2014): 162–63.

  Eurasia that was ancestral to both: N. Patterson, et al., “Ancient Admixture in Human History,” Genetics 192, no. 3 (2012): 1065–93.

  population in western Eurasia: M. Raghavan, et al., “Upper Palaeolithic Siberian Genome Reveals Dual Ancestry of Native Americans,” Nature 505, no. 7481 (2014): 87–91.

  others from North America: M. Rasmussen, et al., “The Genome of a Late Pleistocene Human from a Clovis Burial Site in Western Montana,” Nature 506, no. 7487 (2014): 225–29.

  wild canine in with them: I. Pugach, et al., “Genome-wide Data Substantiate Holocene Gene Flow from India to Australia,” Proceedings of the National Academy of Sciences 110, no. 5 (2013): 1803–8.

  blended with other groups: C. M. Schlebusch, et al., “Genomic Variation in Seven Khoe-San Groups Reveals Adaptation and Complex African History,” Science 338, no. 6105 (2012): 374–79.

  modern human exodus from Africa: H. Reyes-Centeno, et al., “Genomic and Cranial Phenotype Data Support Multiple Modern Human Dispersals from Africa and a Southern Route into Asia,” Proceedings of the National Academy of Sciences 111, no. 20, (2014): 7248–53.

  years ago support this idea: J. Rose, et al., “The Nubian Complex of Dhofar, Oman: An African Middle Stone Age Industry in Southern Arabia,” PLoS ONE 6, no. 11 (2011): e28239.

  “Neanderthals and Homo sapiens are like lions and tigers”: Quote from Colin Groves in this chapter is from my interview with him. Razib Khan suggested to me that the difference was more like polar bears versus brown bears.

  including David Reich at Harvard: R. E. Green, et al., “A Draft Sequence of the Neandertal Genome,” Science 328, no. 5979 (2010): 710–22.

  the beginning of metallurgy: G. Brandt, et al., “Ancient DNA Reveals Key Stages in the Formation of Central European Mitochondrial Genetic Diversity,” Science 342, no. 6155 (2013): 257–61.

  farmers replaced the hunter-gatherers: P. Skoglund, et al., “Genomic Diversity and Admixture Differs for Stone-Age Scandinavian Foragers and Farmers,” Science 344 no. 6185 (2014): 747–750.

  such as addiction to cigarettes: S. Sankararaman, et al., “The Genomic Landscape of Neanderthal Ancestry in Present-Day Humans,” Nature 507, no. 7492 (2014): 354–57.

  lipid catabolism: E. Khrameeva, “Neanderthal Ancestry Drives Evolution of Lipid Catabolism in Contemporary Europeans,” Nature Communications 5, available at DOI: 10.1038/ncomms4584.

  the genomes of modern people: J. Krause, et al., “The Complete Mitochondrial DNA Genome of an Unknown Hominin from Southern Siberia,” Nature 464, no. 7290 (2010): 894–97.

  different, as yet unknown, species: M. F. Hammer, et al., “Genetic Evidence for Archaic Admixture in Africa,” Proceedings of the National Academy of Sciences 108, no. 37 (2011): 15123–28.

  several times over in different groups: S. A. Tishkoff, et al., “Convergent Adaptation of Human Lactase Persistence in Africa and Europe,” Nature Genetics 39, no. 1 (2007): 31–40.

  the better we could process starch: G. Perry, “Diet and the Evolution of Human Amylase Gene Copy Number Variation,” Nature Genetics 39 (2007): 1256–1260.

  a series of apocalyptic Mexican pandemics: R. Acuna-Soto, et al., “Megadrought and Megadeath in 16th Century Mexico,” Revista Biomédica 13 (2002): 289–292.

  New Guinea/Australia bacteria: Y. Moodley, et al., “The Peopling of the Pacific from a Bacterial Perspective,” Science 323, no. 5913 (2009): 527–30.

  based on mouse movements alone: J. B. Searle, et al., “Of Mice and (Viking?) Men: Phylogeography of British and Irish House Mice,” Proceedings of the Royal Society B: Biological Sciences 276, no. 1655 (2009): 201–7.

  did not leave a lasting imprint: E. P. Jones, et al., “Fellow Travellers: A Concordance of Colonization Patterns Between Mice and Men in the North Atlantic Region,” BMC Evolutionary Biology 12, no. 1 (2012): 35.

  Chapter 13: The Past Is Written on Your Face:

  DNA, Traits, and What We Make of Them

  “One of the most fascinating mysteries in Tennessee lore”: W. Winkler, Walking Toward the Sunset: The Melungeons of Appalachia (Macon, GA: Mercer University Press, 2005), ix.

  “explain what a Melungeon is”: Wagne Winkler’s quote comes from my interviews with him. Unless otherwise cited as W. Winkler, Walking Toward the Sunset: The Melungeons of Appalachia (Macon, GA: Mercer University Press, 2005); and W. Winkler, “Melungeons Yesterday and Today: Thirty Years Later,” Melungeon Heritage Association, 2005, available at http://melungeon.ning.com/forum/topics/2005-winkler-article-on-jean-patterson-bible-s-study-of (accessed April 17, 2014), then other Winkler quotes come from my interviews with him.

  “A Melungeon isn’t”: J. Bible, Melungeons Yesterday and Today (Signal Mountain, TN: Mountain Press 5th ed., 1975), 13.

  “After the breaking out of the war”: W. Winkler, Walking Toward the Sunset: The Melungeons of Appalachia (Macon, GA: Mercer University Press, 2005, 261), 271.

  Kennedy, who wrote The Melungeons: N. B. Kennedy and R. V. Kennedy, The Melungeons: The Resurrection of a Proud People: An Untold Story of Ethnic Cleansing in America (Macon, GA: Mercer University Press, 1997). As outlandish as the idea seems that some Melungeons may have descended from settlers who arrived in the United States before Jamestown, or even who came from Roanoke, it’s not that different from another legend-turned-fact further up the East Coast. The stories that Vikings sailed to North America long before the Spanish or the British were considered a fantasy until the 1960s, when the remains of a Norse settlement were dug up in Newfoundland.

  “So smooth of tongue”: W. Winkler, Walking Toward the Sunset: The Melungeons of Appalachia (Macon, GA: Mercer University Press, 2005), 7.

  I want to document as best I can: W. Winkler, Walking Toward the Sunset: The Melungeons of Appalachia (Macon, GA: Mercer University Press,

  2005), xii.

 
“I saw the still-living tentacles”: N. B. Kennedy and R. V. Kennedy, The Melungeons: The Resurrection of a Proud People: An Untold Story of Ethnic Cleansing in America (Macon, GA: Mercer University Press, 1997), 7.

  late nineteenth and early twentieth centuries: This study’s method of selecting subjects was similar to the Viking surname and the Y chromosome study. By choosing names that were independently associated with Viking history and then examining subjects who bore those names for a Viking Y, the researchers in that study maximized the chance that they would find a historical trace of Viking men. In the Melungeon study, by using one of the only independent records of Melungeons that exist, the researchers were able to narrow their focus much more effectively.

  people have shovel-shaped incisors: Finnish people have shovel-shaped incisors too. It’s thought that as the ancient Asian travelers moved into Beringia, they left some genes in the Finnish Sami population.

  “For some reason, people”: Quotes from Richard Scott in this chapter are from my interview with him.

  single letter within a single gene: Variation in the trait is affected by a single letter of DNA; for example, if a particular spot in the gene is filled by a C, then the carrier has wet earwax. If instead the spot is filled by a T, the carrier will have dry earwax. Customers of 23andMe can find out which earwax gene they have. They can also find out if they have the gene that controls the flush reaction to alcohol and the gene that controls the ability to taste bitter tastes, among others.

  way from the full picture: R. Kimura, et al., “A Common Variation in EDAR Is a Genetic Determinant of Shovel-Shaped Incisors,” American Journal of Human Genetics 85, no. 4 (2009): 528–35.

  more than ten thousand Europeans: F. Liu, et al., “A Genome-Wide Association Study Identifies Five Loci Influencing Facial Morphology in Europeans,” PLoS Genetics 8, no. 9 (2012): e1002932.

  They found five genes: PAX3, TP63, and one other gene had already been implicated in other studies, but the association of the remaining two with the face was completely new.