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Angela
28-05-17, 20:44
See:Gloria Gonzalez Fortes et al

http://www.cell.com/action/showImagesData?pii=S0960-9822%2817%2930559-6

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•A large WHG genome component was present in Eneolithic communities in this region

•The further east in Europe, the weaker the genetic component of Anatolian farmers

•Environmental factors may account for a demic diffusion breakdown in these regions


Summary

The transition from hunting and gathering to farming involved profound cultural and technological changes. In Western and Central Europe, these changes occurred rapidly and synchronously after the arrival of early farmers of Anatolian origin [1, 2, 3], who largely replaced the local Mesolithic hunter-gatherers [1, 4, 5, 6]. Further east, in the Baltic region, the transition was gradual, with little or no genetic input from incoming farmers [7]. Here we use ancient DNA to investigate the relationship between hunter-gatherers and farmers in the Lower Danube basin, a geographically intermediate area that is characterized by a rapid Neolithic transition but also by the presence of archaeological evidence that points to cultural exchange, and thus possible admixture, between hunter-gatherers and farmers. We recovered four human paleogenomes (1.1× to 4.1× coverage) from Romania spanning a time transect between 8.8 thousand years ago (kya) and 5.4 kya and supplemented them with two Mesolithic genomes (1.7× and 5.3×) from Spain to provide further context on the genetic background of Mesolithic Europe. Our results show major Western hunter-gatherer (WHG) ancestry in a Romanian Eneolithic sample with a minor, but sizeable, contribution from Anatolian farmers, suggesting multiple admixture events between hunter-gatherers and farmers. Dietary stable-isotope analysis of this sample suggests a mixed terrestrial/aquatic diet. Our results provide support for complex interactions among hunter-gatherers and farmers in the Danube basin, demonstrating that in some regions, demic and cultural diffusion were not mutually exclusive, but merely the ends of a continuum for the process of Neolithization.

Results

We investigated the interactions between hunter-gatherers and Neolithic farmers in the Lower Danube basin in Romania by recovering the genomes of four prehistoric individuals: a Mesolithic hunter-gatherer from Ostrovul Corbului (OC1_Meso) dated at 8.7 thousand years ago (kya), two Mesolithic hunter-gatherers from Schela Cladovei (SC1_Meso and SC2_Meso) dated at around 8.8 kya, and an Eneolithic (the period between the Neolithic and the Bronze Age) individual dated at 5.3 kya from Gura Baciului (GB1_Eneo), located north-northeast of the Iron Gates on a terrace of the Suceag creek (Figure 1 (http://www.cell.com/cms/attachment/2095367637/2077568435/gr1.jpg)A and STAR Methods (http://www.cell.com/current-biology/fulltext/S0960-9822(17)30559-6?_returnURL=http%3A%2F%2Flinkinghub.elsevier.com% 2Fretrieve%2Fpii%2FS0960982217305596%3Fshowall%3Dt rue#sec3), Method Details (http://www.cell.com/current-biology/fulltext/S0960-9822(17)30559-6?_returnURL=http%3A%2F%2Flinkinghub.elsevier.com% 2Fretrieve%2Fpii%2FS0960982217305596%3Fshowall%3Dt rue#sec3.3)). Contact between hunter-gatherers and farmers has been hypothesized for a number of archaeological sites across Europe. In 2012, Skoglund et al. [4] reported the first genomic data suggesting different origins for hunter-gatherers and early farmers in Scandinavia. Further work [1, 5, 6] provided additional paleogenomic evidence that Neolithization was driven by immigration of farming populations, supporting the demic diffusion model, at least for Scandinavia and Western and Central Europe. In Southeast Europe, the Lower Danube Basin has provided some of the best evidence for cultural exchange, and thus possible mixing, between hunter-gatherers and farmers [10, 11, 12]. Archaeological data put the arrival of the typical Neolithic package, including farming, pottery, and new burial practices, at around 8 kya. Isotopic analysis of very late Mesolithic burials from Lepenski Vir around that time revealed several individuals whose diets were relatively high in terrestrial proteins, a profile more typical of farming communities [11]; although the genetic origin of these individuals is unknown, their presence points to contact of this Mesolithic community with farmers (either through cultural exchange or immigration). The presence of personal ornaments of Neolithic type in some Late Mesolithic (8.3–8.0 kya) graves at Lepenski Vir and Vlasac [13] and the recovery of cereal starch granules from dental calculus on Mesolithic teeth from Vlasac [12] further support the hypothesized adoption of new practices by local hunter-gatherers in the Lower Danube basin [11]."

This is their admixture graph. They show CHG in EHG, Lativia Neolithic and Ukraine Neolithic.
http://www.cell.com/action/showImagesData?pii=S0960-9822%2817%2930559-6

This is the Supp. I'm off. Enjoy.
http://www.cell.com/cms/attachment/2095367637/2077568440/mmc1.pdf

bicicleur
28-05-17, 21:03
Maciamo already made a nice resumé :

http://www.eupedia.com/forum/threads/34116-More-genomes-from-Mesolithic-Romania-and-Spain-(Gonzales-Fortes-et-al-2017)