Genomics of Mesolithic Scandinavia reveal colonization routes and high-latitude adaptation

Abstract

Scandinavia was one of the last geographic areas in Europe to become habitable for humans after the last glaciation. However, the origin(s) of the first colonizers and their migration routes remain unclear. We sequenced the genomes, up to 57x coverage, of seven hunter-gatherers excavated across Scandinavia and dated to 9,500-6,000 years before present. Surprisingly, among the Scandinavian Mesolithic individuals, the genetic data display an east-west genetic gradient that opposes the pattern seen in other parts of Mesolithic Europe. This result suggests that Scandinavia was initially colonized following two different routes: one from the south, the other from the northeast. The latter followed the ice-free Norwegian north Atlantic coast, along which novel and advanced pressure-blade stone-tool techniques may have spread. These two groups met and mixed in Scandinavia, creating a genetically diverse population, which shows patterns of genetic adaptation to high latitude environments. These adaptations include high frequencies of low pigmentation variants and a gene-region associated with physical performance, which shows strong continuity into modern-day northern Europeans. 2 29 30 31 32 33 34 35 36 37 38 39 40 41 42(EHGs) from northeastern Europe [14][15][16][17][18][19][20][21]. Archaeology, climate modeling, and genetics, suggest several possibilities for the colonization of Scandinavia, including migrations from the south, southeast, northeast and combinations of these, however, the early post-glacial peopling of Scandinavia remains elusive [1,4,[6][7][8][9][10][11][12][13][14][15][16][17]22,23]. In this study, we contrast genome sequence data and stable isotopes from Mesolithic human remains from western, northern, and eastern Scandinavia to infer the post-glacial colonization of Scandinavia -from where people came,

Four millennia of Iberian biomolecular prehistory illustrate the impact of prehistoric migrations at the far end of Eurasia

“…The statistic of the form f 4 (Chimp, X; Central_LBK_EN and Iberia_EN) measures whether an individual X shares more genetic drift with early Neolithic central Europeans (if the value is negative) or early Neolithic Iberians (if the value is positive). For this analysis, we only used SNP-captured individuals for the reference populations (Central LBK_EN and Iberia_EN) to avoid spurious affinities between references and X due to technological artifacts ( 49 , 50 ). In contrast to prehistoric populations from central Europe, this statistic is consistently shifted toward positive values for prehistoric Iberian groups from different chronologies ( Fig.…”

Skin colour and vitamin D: An update

“…[ 77 ] Thus, the classic light phenotype of Europeans became frequent only within the past 5000 years [ 3,56,70 ] and owes its origin to migrants from Near East and western Asia. [ 48 ]…”

Population Replacement in Early Neolithic Britain

“…This view is inconsistent with the predominantly Anatolian farmer-related ancestry in published data from British Early Neolithic farmers 8 , but the extent to which local British huntergatherer populations contributed to the first British farming populations, as well as the relationship of British hunter-gatherers to continental hunter-gatherer populations remains unresolved. These questions are of interest as Britain is situated between two geneticallydistinct contemporaneous groups of Mesolithic hunter-gatherers -Western European and Scandinavian (WHGs & SHGs) 16 . The British Isles could also have putatively harboured ancestry from hunter-gatherers related to earlier Magdalenian Palaeolithic groups that recolonised Europe from the southwest after the Last Glacial Maximum (~21 to 17 kBP) 17 .3 Here, we report the first genome data from six Mesolithic (including the 'Cheddar Man' skeleton from Gough's Cave, Cheddar Gorge, Somerset) and 16 Neolithic British individuals, and combine it with new and already reported data from 51 previously published Neolithic British individuals 8 to characterise the Mesolithic and Neolithic populations of Britain ( Figure 1).…”