Right - but this map (as other maps) shows the maximal extension of cultural expansion, but does not say anything about demic density of these cultures "initiators" nor even their density of cultural implantation -I hold saying Brittany received few men of the original centers of these 2 neolithical cultures : Cardial left more human remnants in western and southern France a sa whole than in Brittany and "Rubané" people left more human remnants in Alsace/Elsass or Normandy than in Brittany
It's true, of course, that it's often unclear how much demic involvement there is in any given cultural expansion. That said, what evidence leads you to believe that Brittany didn't receive substantial members from the centers of these two neolithic cultures? Or at least significant gene flow via their descendents, descendents who, at least outside the Balkans, seemed to engage in a rather limited amount of inter-marriage with the locals, thereby preserving their genetic signatures.
I'm waiting to see the actual paper, but if the abstract is correct, this four thousand year old farmer from Burgos (2,000 B.C.) is much the same as the farmer from Sweden, who is much the same as the farmer from the Tyrol. Yes, Gok 4 may have mixed a little more with the prior inhabitants, but basically, farmers from very widely separated areas of Europe share a remarkable genetic similarity.
http://www.diva-portal.org/smash/rec...d=diva2:665597
The spread of farming, the neolithisation process, swept over Europe after the advent of the farming lifestyle in the near east approximately 11,000 years ago. However the mode of transmission and its impact on the demographic patterns of Europe remains largely unknown. In this study we obtained : 66,476,944 bp of genomic DNA from the remains of a 4000 year old Neolithic farmer from the site of El Portalón, 15 km east of Burgos, Spain. We compared the genomic signature of this individual to modern-day populations as well as the few Neolithic individuals that has produced large-scale autosomal data. The Neolithic Portalón individual is genetically most similar to southern Europeans, similar to a Scandinavian Neolithic farmer and the Tyrolean Iceman. In contrast, the Neolithic Portalón individual displays little affinity to two Mesolithic samples from the near-by area, La Brana, demonstrating a distinct change in population history between 7,000 and 4,000 years ago for the northern Iberian Peninsula.
I think it's important to remember how few H/G's there were in Europe when the First Farmers arrived. I don't think it's analogous to the situation in Mexico or South America, where the rise of agriculture had led to the growth of large populations in certain areas.
Whatever more H/G or more northeastern input contributed to the genome of Europeans would not seem to have arrived in Iberia, for example, until perhaps 1600 B.C. where it made less of an impact than in Central Europe and the Isles perhaps because the central European and Isles farming communities had collapsed due to some combination of climate change, environmental collapse because of over use of the soil, the fact that the Neolithic package of the time was not yet appropriate for the climate and soils of the area, or even that some newcomers from the steppe brought with them some particularly nasty plague, as they did many times thereafter.