On the Mesolithic colonization of Scandinavia (Günther et al. 2017 preprint)

Over at bioRxiv at this LINK. The main takeaway point from this preprint is that Scandinavia was a more happening place than most of the rest of Europe during the Mesolithic, because at the time it was the meeting place between two relatively divergent forager groups, West European hunter-gatherers (WHG) and East European hunter-gatherers (EHG), that entered the peninsula from different directions, the southwest and northeast, respectively, and mixed to form Scandinavian hunter-gatherers (SHG). Other key points:

- EHG probably dispersed across Scandinavia in a counter-clockwise direction via an ice-free route along the Atlantic coast in what is now Norway, because SHG samples from northern and western Scandinavia show more EHG ancestry than those from southern and eastern Scandinavia

- at least 17% of the SNPs that are common in SHG are not found in present-day Europeans, suggesting that a large part of European variation has been lost since the Mesolithic

- although it's unlikely that SHG made a significant contribution to the present-day Northern European gene pool, some gene-variants common in SHG that appear to be associated with metabolic, cardiovascular, developmental and psychological traits are carried at high frequencies by present-day Northern Europeans, especially compared to present-day Southern Europeans, probably due to strong selective pressures specific to northern latitudes in Europe

- SHG is inferred to have had fair skin and varied blue to light-brown eye color, which makes sense considering that it was a mixture of apparently fair-skinned/brown-eyed EHG and dark-skinned/blue-eyed WHG, except that the frequencies of blue-eyed variants and one fair-skinned variant in SHG are much higher than expected from its EHG/WHG mixture ratios, again pointing to strong selective pressures specific to northern latitudes in Europe acting upon certain gene-variants

- a 3D computer generated facial reconstruction of an SHG female based on data from a very high (57x) coverage genome sequence looks, at least to me, like a fairly typical present-day Northern European woman (see Figure S9.1 in the supp info here), though I suspect that the result might be biased in some way, simply because it's impossible to know whether variants associated with specific facial traits in present-day Northern Europeans were also associated with the same facial traits in SHG.

Citation...

Günther et al., Genomics of Mesolithic Scandinavia reveal colonization routes and high-latitude adaptation, bioRxiv, Posted July 17, 2017, doi: https://doi.org/10.1101/164400