One hypothesis for how humans transitioned from developing a robust Neandertal visage in maturity to retaining finer features throughout life is that we “self-domesticated” our face. This idea suggests that as humans increasingly relied on peaceable social interactions to flourish, our ancestors began selecting mates with less aggressive features for facial appearance and other traits. But genetic evidence linking facial characteristics to this self-domestication process has been scant.
A new study published on December 4 in Science Advances provides a missing link. The results show that DNA changes underlying facial development differ distinctly between today’s humans and our closest extinct relatives, the Neandertals and Denisovans—another ancient branch of the human family tree.
These differences would be expected if modern humans are a self-domesticated species, says Richard Wrangham, a professor of biological anthropology at Harvard University, who was not involved in the work. Previous studies circled around genes potentially linked to domestication in humans, he says, but the “critical advance” of the new paper is that it takes one important gene candidate and ties it to a predicted result of domestication: finer facial features.
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