Spencer Wells is Explorer in Residence at the National Geographic Society. He has impeccable credentials: Ph.D. with Richard Lewontin, and postdoc with Luigi Luca Cavalli-Sforza and Sir Walter Bodmer. Wells heads the The Genographic Project, a project that collects and analyzes DNA samples from individuals around the world in an attempt to understand human evolution and migration.
Wells spoke last Wednesday morning in the amphitheater. He gave an interesting and informative lecture on "Deep Ancestry: Inside the Genographic Project." Most Sandwalk readers are familiar with the basic results of these studies. They indicate that modern humans originated in Africa and rapidly spread from there to all other continents. The controversy is about timing. Wells promoted the view that the last migration out of Africa took place only about 50,000 years ago.
Before the lecture, I explained to my students that this type of DNA sequence analysis relies on the fact that different human populations are genetically distinguishable. What this means is that scientists are able to tell what group you belong to by looking at your DNA. This establishes that there is a biological difference between races/populations. That's why you can trace migration routes.
Wells explained this very well without using the "race" word. Africans split from the groups on all other continents less than 100,000 years ago. Later on the migrating population subdivided into Europeans, Asians, and native Americans (+ others). In response to a question after the lecture he made the standard politically correct statement ...
Listen, I’m a scientist, and to the extent that people listen to scientists, I would like them to absorb this message, that scientifically speaking, races have no biological basis.This got the expected round of applause from the audience. (They love that stuff at Chautauqua.) Nobody seemed to notice the discrepancy between what he said in his lecture and the idea that "races have no biological basis."
Aside from that minor glitch, Wells did a fine job of explaining the science behind these studies. The Genographic kits were on sale at the Chautauqua bookstore and I suspect they sold a lot of kits last week. According to Wells, the Genographic Project is the largest DNA typing program in the world and the information it returns to you on your ancestry is much more reliable—and cheaper—than many of the for-profit companies that have sprung up recently.
[Photo Credit: Chautauquan Daily]
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