Was Human Evolution Guided By What Men Think is Hot?
A recent Slate article by Katy Waldman challenges a theory asserted by University of Washington geneticist Joshua Ackey that says that when it comes to natural selection, it all comes down to the "sexually visible effects."
Waldman cites a 35,000-year-old gene mutation called EDAR, which studies have linked to physical traits common in East Asians — thick hair, distinctively-shaped teeth, small breasts and extra sweat glands. In an article that ran in the New York Times science section last week, British-born science writer Nicholas Wade hypothesized that the characteristic that made EDAR so valuable was the sweat glands; they were necessary for people to stay cool while hunting and gathering in China’s formerly smoggy, warm climate.
To Waldman’s dismay, Wade then quotes Joshua Ackey, saying "thick hair and small breasts are visible sexual signals which, if preferred by men, could quickly become more common as the carriers had more children." He claims that "the sexually visible effects of EDAR are likely to have been stronger drivers of natural selection than sweat glands." In other words (Waldman’s): "it all comes down to lady parts."
Yes, this might "assume alarming passivity on the part of females," if you interpret the genetic mutation as flourishing because men wanted to have sex with the women that carried it. And yes, other factors have proven to play much larger roles in human survival, like being able to store fat to biologically manage famine. But, this evidence does not strike down the theory that the sexual selection of female partners by males, based on the response of "sexually visible effects," may have very well influenced the human female phenotype on a smaller scale than other factors. Waldman finds this notion ridiculous, but her view may be grounded more in her political beliefs — in that any assertion of male power over females should be challenged — than in science.
While there has been no established evidence that the male sexual preference — in the specific East Asian case cited in the article — did, in fact, help mold the modern woman, responding by claiming the notion is absurd is rather absurd in itself.
Before I piss off too many feminists, don’t get me wrong; sexual preference is clearly not the foremost or leading factor in the evolution of the modern woman. It’s a secondary effect, at best. But putting science aside and claiming that males, as a group, will have sex with just about anything that has a pulse, is no way to effectively argue against the theory that male sexual preferences have some impact on evolution. It’s pointless arguing with individual males in this regard because they will all say they have standards. Sure, they do, but that doesn’t say anything about how high or low those standards are.
It makes no sense to claim that display-based sexual selection on the part of males could not possibly have any influence at all on the modern female’s phenotype, which is the tone suggested by Waldman. If individuals with the EDAR gene tended to (even by small margins) be more sexually attractive, which ultimately led to them having more offspring, then male sexual selection has to be at least in part why this mutation became common. The point is that sexual selection isn’t "dingbat" science — it’s real, and it acts on humans as on animals. After all, there is pretty much no other explanation for things the spread of blue eyes out of Northern Europe, which occurred only a few thousand years ago.