[T]he dominant lineage today among Basques and Western Europeans in general, haplogroup H, was already present in Magdalenian times in Cantabria, what is consistent with it being found in Epipaleolithic Portugal and Oranian Morocco and really puts to rest the hypothesis that promoted that it had arrived from West Asia with Neolithic colonists (something argued as a matter of fact but without any clear evidence). As of late, although I have yet to formalize it somehow, I've been thinking that a serious possibility is that mtDNA might have spread partly with Dolmenic Megalithism. While there is some apparent Neolithic expansion of H in the Basque area (apparent in this paper and resulting in an almost modern genetic pool), in other parts of Europe this is less obvious, with H showing up but not reaching modern levels just with Neolithic. In fact the loss of other Neolithic lineages like N1a strongly suggests that the populations of Central Europe were largely replaced after the Early Neolithic. Where from? Again from Southwest Europe, I suspect but not in the context that was once believed of Magdalenian expansion, but maybe in the context of Megalithic expansion instead, with origin not in the Franco Cantabrian region but in Portugal. This is just a draft hypothesis that I have mentioned before only in private discussions or at best in the comments section somewhere, and certainly it would need more research. My main argument is that before these results for Cantabria, the only pre-Neolithic location where the data clearly suggested very high levels of mtDNA H (near 75%) was Portugal (Chandler 2005) and Portugal played a major role in Neolithic and Chalcolithic Western Europe. As I said above, ancient Portuguese apparently developed the Dolmenic Megalithic pehnomenon (culture, religion...), later they developed some of the earliest Western European civilizations, since the Third millennium BCE, specially Zambujal (also at Wikipedia), which were central elements of this long-lasting Megalithic culture and later of the Bell Beaker phenomenon as well. And we need very high levels of mtDNA H in a colonizer population to changed the genetic landscape from c. 20% H into c. 45% H, we need something like a 70-80% H ancestral population unless replacement was total, what I think unlikely. What happened to that overwhelmingly H population of Portugal (assuming that the hypothesis is correct)? They were probably colonized in due time, possibly in the Bronze Age (the mysterious archaeological "horizons" that replace urban life in much of Southern Portugal in that period with their strange crab-shaped elite tombs, vaguely resembling Mycenaean circular walled ones) and/or in the period of Celtic invasions from inland Iberia later in the Iron Age (Hallstat periphery).The second paper looks at ancient autosomal DNA evidence from 5000 years ago from Sweden that suggests that there were distinct Russian and Iberian Neolithic populations that were present then. The Russian-like population was a Pitted Ware hunter-gather population. The Neolithic population was the one that was similar to modern Iberians. This largely confirms prior research with other methods.
Friday, April 27, 2012
New European Ancient DNA Papers
Maju has unearthed two new ancient DNA papers (he also notes that a third paper with ancient mtDNA from Biscany is coming soon). The most notable is an ancient mtDNA paper from Basque country which shows, for the first time in a formally published paper, solid evidence of mtDNA haplogroup H in Southwest Europe in two Magdelenian samples (i.e. before the arrival of herding and farming). Previous studies have found pre-Neolithic samples to be dominated by mtDNA haplogroup U. Also notable from the perspective of his thoughts on the subject is his willlingness to consider the possibility that mtDNA haplogroup H spread not in the Upper Paleolithic era, but sometime in the early to middle Neolithic or Copper Age, a view that I generally agree with: