Origin: A Genetic History of the Americas

Jackson). He published extensively on functional anatomy, but also
conducted and published research that undermined racial typologies. In one
of his most famous works, “Race and Runners,” Cobb disproved the
popular notion that African American sprinters, broad jumpers, and other
athletes had an innate advantage owing to anatomical differences from
runners of other races. “Genetically we know they are not constituted
alike,” he wrote. “There is not one single physical feature, including skin
color, which all of our Negro champions have in common which would
identify them as Negroes… In fact if all our Negro and white champions
were lined up indiscriminately for inspection, no one except those
conditioned to American attitudes would suspect that race had anything
whatever to do with the athletes’ ability” (33).
Despite the efforts of the antiracist factions of the discipline, physical
anthropology had already provided “scientific support” for racial
categorizations in the early 20th century. These categorizations are now
firmly and perniciously rooted in the public mindset, contributing to a
terrible legacy of discrimination and violence against Black, Indigenous,
and other people of color.
Many physical anthropologists grappled mightily with the concept of
biological race using morphological data. Today, the extraordinarily
detailed view of human variation that genetics offers us reveals the
flimsiness of the typological approach (34). Early genetic studies in the
20th century—focused on mitochondrial and Y chromosome variation—
showed that the racial categories so often used by early physical
anthropologists did not correspond to actual patterns of genetic variation.
Our ability to sequence whole genomes—the most amount of information
about a person’s genetic ancestry that it’s possible to obtain—confirmed
this: While populations vary genetically, this genetic variation does not
follow patterns of racial categories articulated by Blumenbach, Morton, and
others. If that statement surprises you, it is because these concepts are so
deeply engrained within our culture.
Humans’ DNA is 99.9% identical. It is that tiny difference—just 0.1%—
along with what we loosely call the “environment” xiv that accounts for the
variation in our remarkable outward appearance, or phenotype. Much of
that genetic variation is distributed in patterns called clines, or gradually
changing over geographic distance. It makes sense when you think about it: