Ancient DNA from Hunter-Gatherer and Farmer Groups from Northern Spain Supports a Random Dispersion Model for the Neolithic Expansion into Europe

Abstract

Background/Principal FindingsThe phenomenon of Neolithisation refers to the transition of prehistoric populations from a hunter-gatherer to an agro-pastoralist lifestyle. Traditionally, the spread of an agro-pastoralist economy into Europe has been framed within a dichotomy based either on an acculturation phenomenon or on a demic diffusion. However, the nature and speed of this transition is a matter of continuing scientific debate in archaeology, anthropology, and human population genetics. In the present study, we have analyzed the mitochondrial DNA diversity in hunter-gatherers and first farmers from Northern Spain, in relation to the debate surrounding the phenomenon of Neolithisation in Europe.Methodology/SignificanceAnalysis of mitochondrial DNA was carried out on 54 individuals from Upper Paleolithic and Early Neolithic, which were recovered from nine archaeological sites from Northern Spain (Basque Country, Navarre and Cantabria). In addition, to take all necessary precautions to avoid contamination, different authentication criteria were applied in this study, including: DNA quantification, cloning, duplication (51% of the samples) and replication of the results (43% of the samples) by two independent laboratories. Statistical and multivariate analyses of the mitochondrial variability suggest that the genetic influence of Neolithisation did not spread uniformly throughout Europe, producing heterogeneous genetic consequences in different geographical regions, rejecting the traditional models that explain the Neolithisation in Europe.ConclusionThe differences detected in the mitochondrial DNA lineages of Neolithic groups studied so far (including these ones of this study) suggest different genetic impact of Neolithic in Central Europe, Mediterranean Europe and the Cantabrian fringe. The genetic data obtained in this study provide support for a random dispersion model for Neolithic farmers. This random dispersion had a different impact on the various geographic regions, and thus contradicts the more simplistic total acculturation and replacement models proposed so far to explain Neolithisation.

Ancient mitochondrial lineages support the prehistoric maternal root of Basques in Northern Iberian Peninsula

“…In order to establish their antiquity and obtain information about their diet these remains were radiocarbon dated and subjected to the analysis of stable isotopes of carbon 13 C/ 12 C (δ 13 C) and nitrogen 15 N/ 14 N (δ 15 N; Table 1, Supplementary Dataset S1 and Supplementary Appendix).…”

“…On the other hand, Mesolithic sample from Santimamiñe, S.12N, was joined to previously studied pre-Neolithic/hunter-gatherer remains from the northern Iberian Peninsula (HGNI). 13,14 A PCA was performed with haplogroup frequencies of European populations from different prehistoric periods (Figure 3, Supplementary Dataset S3).…”

“…In contrast with several studies focused on the analysis of the current autochthonous population, there are only a few reports on pre-Neolithic samples from the Franco-Cantabrian region. 13,14 These studies are grounded in the supposedly genetic continuity between the Palaeolithic huntergatherers and the autochthonous Basque population. 15,16 Herein we report a study on ancient maternal lineages of the Franco-Cantabrian region and their persistence in modern populations.…”

Echoes from Sepharad: signatures on the maternal gene pool of crypto-Jewish descendants

“…54 Although this haplogroup was found in Neolithic and Mesolithic skeletal remains from Central and Northwest Europe, [55][56][57] it was absent in previous studies on Iberian Neolithic populations, suggesting a rather uneven genetic and geographical spread of this lineage across Europe. 58,59 However, more recently, Gamba et al 60 detected this lineage in Neolithic northeast Iberia, evidencing a possible scenario of several Neolithic colonization events along the Mediterranean, from the Near East. The samples from Braganc¸a cluster into sub-haplogroups N1a and N1b and similarly to what was observed for HV0, NJ networks of N1b revealed no CR haplotype sharing with the general Portuguese population, except for four individuals from Miranda, an isolated population from the same geographical area as well as with two samples from Zamora 41,42 (Supplementary Figure 3).…”

New clues to the evolutionary history of the main European paternal lineage M269: dissection of the Y-SNP S116 in Atlantic Europe and Iberia

“…22 Thus, the spread of Neolithic culture would mean a lower demic movement. The theories that argue for an origin in the East and during the Neolithic period assume a rapid expansion of M269 throughout Europe, replacing most of the previously settled haplogroups, which would be compatible with a main scenario of demic diffusion.…”