This makes Alaska — and specifically the interior of Alaska, which is the most likely location for the residual Ancient Beringian population after the main southward expansion — the most important region in North America for future ancient DNA research on early American populations.

Additional ancient genomes from Alaskan sites of similar or greater age to USR1 would dramatically increase our understanding of the early structure of the founding population, the timing and geography of the Ancient Beringian / proto-First American divergence, and the fate of the Ancient Beringian lineage in the millennia following USR1.

The archaeological record of Alaska is rich with sites from the relevant period — the late Pleistocene and early Holocene — many of which have been excavated or at least surveyed in sufficient detail to know that human remains might be present.

The challenge is that ancient DNA preservation in Alaskan sites is variable, dependent on the specific burial conditions and the thermal history of the site since deposition.