At the end of last year I predicted that full genome sequencing would begin turning up evidence for more archaic admixture in Africa. Halfway into the year, it appears that my prediction has proven to be correct: a new study in Cell by Lachance et al. documents the existence of such admixture between an archaic hominin and Pygmies from Cameroon, and the East African Hadza and Sandawe.
Archaic admixture in Biaka and San was previously detected by Hammer et al. Hence, we now have evidence for archaic admixture from several regions that encompass all major regions within sub-Saharan Africa. It seems that my old idea about layers of Palaeoafricans being absorbed by early modern humans in Africa was basically correct, and that some of these layers correspond to archaic African populations.
But not all agree. The New York Times coverage of the paper suggests that there is a controversy surrounding the new study:
All human fossil remains in Africa for the last 100,000 years, and probably the last 200,000 years, are of modern humans, providing no support for a coexistent archaic species.
Paleoanthropologists like Dr. Klein consider it “irresponsible” of the geneticists to publish genetic findings about human origins without even trying to show how they may fit in with the existing fossil and archaeological evidence. Dr. Akey said he agreed that genetics can provide only part of the story. “But hopefully this is just a period when new discoveries are being made and there hasn’t been enough incubation time to synthesize all the disparities,” he said.
This is of course completely wrong; as Chris Stringer mentions in the NY Times piece, there is ample evidence for archaic Africans down to quite recent times in the form of Iwo Eleru and Ishango, and there is more evidence besides. Indeed, it does not appear at all that there was a punctuational event that replaced archaic hominins with a new Homo sapiens species. If anyone wants to criticize the new study, complaining about it being in disharmony with physical anthropology is not a good way to go about it. Nor is it, of course, “irresponsible” to report the new findings.
Source and full article: Dienekes’ Anthropology Blog