‘Everyone is African’
Geneticist, professor talks about race, genetics, origin of human race
Geneticist, author, professor and artist Dr. Daniel Fairbanks gave scientific proof that the entire human population hails from Africa during his lecture Thursday titled “Everyone is African: How Science Explodes the Myth of Race.”
The lecture, held at Texas A&M University as part of the Program for Learning and Engagement’s series on “Race and Ethnicity,” was based on his book by the same name, and explores data including genetic mutations, DNA and fossil evidence showing that humans as we know them originated in the eastern portion of the African continent.
“To understand how genetic diversity is distributed among humans, we must recognize that we were African in origin and the majority of the time our species … have been in existence, was entirely confined to Africa,” Fairbanks said, “and it is only recently, meaning in the past 60,000 years or so, that people have lived outside of Africa. That period of time has allowed for new variants to arise both in the people who remained in Africa and those who went outside of it.”
He explained the oldest fossils of the earliest human-like species, called hominins, are seven million years old and were found in Africa. These had a larger brain casing (skull) and showed other anatomical traits of humans, including a pelvis that showed a transition to an upright posture. As early as four million years ago,
the species began developing an upright posture in all of Africa, with fossils of homo erectus, upright humans, dating to one million years ago.
“That’s the first indication of human like species leaving Africa,” Fairbanks said. “There are fossils of homo erectus that go across Asia.”
He went on to describe the European and Middle Eastern migration of Neandertals about 700,000 years ago, adding the species eventually died out.
Other species survived, with many traveling into eastern Europe and southern Asia, and some taking the path across a land bridge to North America and eventually in South America – all areas of the world containing indigenous tribes with the same initial genetic background, he said.
He detailed how the gene for male pattern baldness must have originated before the migration, because it’s found all over the world. Also, he explained the genetics and natural selection of humans’ pigmentation loss as they traveled to northern parts of the Earth, areas with less sunlight than those of equatorial countries.
Fairbanks said each step in migration also created a reduction in genetic diversity, and by tracing the DNA, scientists reaffirmed what fossils had shown – human life began in Africa.
“Wherever you have the greatest genetic diversity in a species, that’s the most likely place for its origin, and that’s unequivocally Africa for humans,” he said. “There is more genetic diversity in Africa than the rest of the world combined. Which seems kind of counterintuitive to us, but that’s what the DNA data shows.”
Fairbanks said race is very real from a social standpoint, but not so much from a biological one.
“We have so much discussion about diversity and racial tensions and other sorts of things, and I think understanding the science gets rid of some of the preconceptions that some people have about notions of racial superiority that are somehow are biologically determined,” he said. “The genetic diversity that we have in our nation, which is the consequence of our history, is really something to celebrate rather than to denigrate.”