Genetic Genealogy & Ancient DNA (TITLES/ABSTRACTS)

[JMcB]

Courtesy of lg16:


Genomic ancestry and social dynamics of the last hunter-gatherers of Atlantic France

Luciana G. Simões, Rita Peyroteo-Stjerna, Grégor Marchand and Mattias Jakobsson



Significance:

Since the early Holocene, western and central Europe was inhabited by a genetically distinct group of hunter-gatherers. We generated different types of biomolecular data, including deep coverage complete genome sequencing, from human skeletal remains buried in the iconic sites of Téviec and Hoedic in Brittany, representing some of the last hunter-gatherers of western Europe. The data show that these last foragers were part of a network of people who maintained exogamic practices. These socio-cultural dynamics contributed to avoiding inbreeding. Some of the forager individuals overlapped in time with the arrival of Neolithic farmers to neighboring regions. However, we did not find any farmer-associated ancestry in the analyzed hunter-gatherers and the mate-exchanging networks appear to be exclusive for the foraging group.


Abstract:

Since the early Holocene, western and central Europe was inhabited by a genetically distinct group of Western Hunter-Gatherers (WHGs). This group was eventually replaced and assimilated by the incoming Neolithic farmers. The western Atlantic façade was home to some of the last Mesolithic sites of mainland Europe, represented by the iconic open-air sites at Hoedic and Téviec in southern Brittany, France. These sites are known for the unusually well-preserved and rich burials. Genomic studies of Mesolithic European hunter-gatherers have been limited to single or a few individuals per site and our understanding of the social dynamics of the last Mesolithic hunter-gatherers of Europe and their interactions with incoming farmers is limited. We sequenced and analyzed the complete genomes of 10 individuals from the Late Mesolithic sites of Hoedic, Téviec, and Champigny, in France, four of which sequenced to between 23- and 8-times genome coverage. The analysis of genomic, chronological and dietary data revealed that the Late Mesolithic populations in Brittany maintained distinct social units within a network of exchanging mates. This resulted in low intra-group biological relatedness that prevented consanguineous mating, despite the small population size of the Late Mesolithic groups. We found no genetic ancestry from Neolithic farmers in the analyzed hunter-gatherers, even though some of them may have coexisted with the first farming groups in neighboring regions. Hence, contrary to previous conclusions based on stable isotope data from the same sites, the Late Mesolithic forager community was limited in mate-exchange to neighboring hunter-gatherer groups, to the exclusion of Neolithic farmers.

https://www.pnas.org/doi/10.1073/pnas.2310545121