Advanced DNA sequencing has given researchers new insight into the origin of the first human settlers on the Scandinavian Peninsula. The new data suggests that these settlers came from two distinct regions, and the subsequent population evolved to survive extreme weather conditions.
Evidence shows that there was a human presence on the Scandinavian Peninsula beginning nearly 12,000 years ago, yet the routes and origins of the migrants have remained a mystery.
The research team sequenced the genomes of seven hunter-gatherers recovered from across Scandinavia, which dated back between 9,500-6,000 years old. The experts discovered that migrations into the Scandinavian Peninsula most likely followed two routes – one from central Europe and one along the Norwegian Atlantic Coast.
The two populations mixed in Scandinavia, and created a genetically diverse group of individuals with many genetic variants that are not found in modern-day Europeans.
The experts analyzed the DNA evidence for signs of adaptation to the cold and low daylight conditions of high-latitude regions. They found several genetic variants which were linked to a gene associated with physical performance and, according to the researchers, are likely associated with physiological adaptation to cold as well.
The genomes also revealed a high frequency of genetic variants linked to reduced skin pigmentation, which is a known adaptation to the low UV radiation found in high-latitude environments.
Torsten Günther is a population geneticist at Uppsala University and one of the lead authors of the study.
“We used cutting-edge genomic approaches to investigate hypotheses about the early colonization of northern Europe after the ice-sheet of the last glaciation retracted,” said Günther. “It is really great to see how evidence from different disciplines can be combined to understand these complex past demographic processes.”
“Our findings are important for human genetics, archaeology and anthropology, and it will be interesting to see what similar approaches can tell us about the post glacial population dynamics in other parts of Europe and the rest of the world.”
The is published in the open access journal PLOS Biology.