Say you have a abstruse paper such as, Accelerated genetic drift on chromosome X during the human dispersal out of Africa:
Comparisons of chromosome X and the autosomes can illuminate differences in the histories of males and females as well as shed light on the forces of natural selection. We compared the patterns of variation in these parts of the genome using two datasets that we assembled for this study that are both genomic in scale. Three independent analyses show that around the time of the dispersal of modern humans out of Africa, chromosome X experienced much more genetic drift than is expected from the pattern on the autosomes. This is not predicted by known episodes of demographic history, and we found no similar patterns associated with the dispersals into East Asia and Europe. We conclude that a sex-biased process that reduced the female effective population size, or an episode of natural selection unusually affecting chromosome X, was associated with the founding of non-African populations.
Over at Gene Expression Classic p-ter expresses his befuddlement:
At the same time, another group (Keinan et al.) was independently looking at this issue in other datasets. Their analysis, published today is markedly different. In particular, they see the exact opposite of the pattern in Hammer et al.–a decrease in the X/autosome ratio in effective population size compared to 0.75 (a figure from their paper is on the right. Note that the y-axis is the same in both this and the Hammer et al. figure–the x/autosome ratio in Ne. In both, the solid horizontal line is at 0.75). . And this is not due to extremely different methodologies–one of the analyses presented by Keinan et al. is very similar to that in Hammer et al., only using different data.
So this is all a bit odd, to say the least.
All right. So how does this play in the press? They go crazy! Did warfare drive out-of-Africa migration?:
Roving bands of men might have waged history’s first traceable war against the ancestors of all Europeans, Asians and other non-Africans, some 60,000 years ago.
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