A short article in The Conversation by Jan Apel describes some new research from Mattias Jakobsson’s lab on the population mixture that gave rise to the Mesolithic people of Scandinavia: “Ancient DNA sheds light on the mysterious origins of the first Scandinavians”.
This contradiction between genetics and geography can only be explained by two main migrations into Scandinavia. It would have started with an initial pulse from the south – modern day Denmark and Germany – that took place just after 11,700 years ago. Then there would have been an additional migration from the northeast, following the Atlantic coast in northern Finland and Norway becoming free of ice.
I think this work is exciting. The retreat of the European ice sheet left an opportunity for ancestral hunter-gatherers to colonize Scandinavia. The genetic data show that even this very simple biogeographic setting nonetheless gave rise to a complex mixture of populations from multiple sources, over a few thousand years of time.
Later, the introduction of farming into the region led to its own complex series of genetic migrations and interactions.
I can’t wait until we have equivalent or larger samples of individuals from other parts of the world of the same age.
Günther T, Malmström H, Svensson EM, Omrak A, Sánchez-Quinto F, Kılınç GM, et al. (2018) Population genomics of Mesolithic Scandinavia: Investigating early postglacial migration routes and high-latitude adaptation. PLoS Biol 16(1): e2003703. https://doi.org/10.1371/journal.pbio.2003703