Ancient human genomes suggest three ancestral populations for present-day Europeans has finally be published in journal, Nature. This is important as a validation and confirmation of the strange results which were reported therein. One simple finding which I haven’t commented on in too much detail is how clearly Europe as a biogeographic entity is distinct from the Near East genetically. Arguably, it’s more than a cultural construct. Europeans share descent in part from an ancient lineage which dates to the late Pleistocene, and is not shared with those outside Europe (haplogroup I-M70 in Y chromosomes). To an extent this isn’t totally surprising, as water barriers are often incredibly good at allow for populations to drift apart due to lack of reoccurring gene flow (even ones as narrow as the Straits of Gibraltar and the Bosporus). On the other hand there is arguably more continuum with populations in Northeast Asia, though much of that is relatively recent in vintage (e.g., many of the Central Asian Turkic groups occupy a position between west and east Eurasia, but they are relatively recent admixtures).

Finally, this paper leaves a lot of unanswered questions, which I suspect will be answered soon:

Several questions will be important to address in future ancient DNA work. One question concerns where and when the Near Eastern farmers mixed with European hunter-gatherers to produce the EEF. A second question concerns how the ancestors of present-day Europeans first acquired their ANE ancestry. Discontinuity in central Europe during the late Neolithic (~4,500 years ago) associated with the appearance of mtDNA types absent in earlier farmers and hunter-gatherers raises the possibility that ANE ancestry may have also appeared at this time. Finally, it will be important to study ancient genome sequences from the Near East to provide insights into the history of the basal Eurasians.

One thing to note about “basal Eurasians” is that they claim that it shares “drift” with all other non-Africans. This implies that they were not post-Out-of-Africa migrants from Sub-Saharan Africa, but shared in a common Out-of-Africa history with the other populations of the world. I hope that deeper study of non-European populations might be able to get us a better sense of where basal Eurasians shake out.