#1 - Posted: 06/08/2008 15:17
Here’s more evidence of the problem with standard sexual selection theory. A paper in 5 August PNAS shows that the old idea that alpha males aren’t guaranteed long-term success. Anthropologists and geneticists sifted through the DNA of 1269 males from 41 Indonesian communities, looking back more than 3000 years. Only 5 of those communities seem to have been dominated by a few male lines. Interestingly, 3 of the 5 were polygamous communities – which have obvious benefits for the dominant males. Turns out the main author has been aware of this for a while – there’s a video of him speaking on it here , as well as a summary which includes:
A central tenet of human behavioral ecology holds that facultative behaviors, such as those associated with dominance, produce fitness effects that are subject to cultural selection. “In more than one hundred well studied societies", according to a recent review, “high-ranking men have the right to more wives." But evidence for such selection is inconclusive, based on short-term statistical associations between behaviour and fertility. And the underlying model of selection, based on Fisher´s “fundamental theorem of natural selection" (circa 1930), is no longer taken seriously in population genetics.
The New Scientist story is here.