A recent study, Balaresque et al. (2010) in PLoS Biology, reports that some 80% of the genetic origin of European males probably originates from an expansion in Anatolia after the Ice Age. They link it to the spread of agriculture in Europe.
It pleases me to see that they are using the geographical tools for analysis that I advocated in Européernas DNA (2003). The number of haplotypes on the Y chromosome has increased significantly since I did that little study. Back then, the available data indicated that haplogroup R1b was the dominating one in Western Europe, and R1a1 in Eastern.
The new study shows that a sub-haplogroup to R1b, namely R1b1b2, accounts for the majority of Y chromosomes in the west (cf. Fig. 1B). The same figure shows the so-called microsatellite variance, in panel C. The variance is expected to be highest in the area where the mutation happened – in this case in Anatolia near the Aegean Sea. Areas with high concentration and low variability indicate a founder effect, i.e., a rapid population growth from a small original group. We see this in the – generally speaking – Celtic area of Europe.
The authors connect is to the Neolithic expansion, which I have referred to as the Neolithic ®evolution (since although it was a long and slow process the term Revolution has become almost a fixed idea). Perhaps they are right, but perhaps not. Their conclusion assumes that men had a gender-specific advantage of agriculture, which I doubt, since it was typically a women’s task.
Also, the fact that there appears to be a correlation to the Celts should raise an alert. Agriculture spread, from what I seem to recall from doing research for that study, along the Danube. It does not match the pattern of R1b1b2 at all. On the other hand, Celts are famous for weapons. It is rather self-evident that having the better weapon is a gender-specific advantage for males.
Although it is an interesting article, I am sure, there is still much more to be done, and I am certain that new results will come out when geneticists become (even) more inter-disciplinary in their work.