Evolving Methods

Evolutionary psychologists commonly assert that some trait or propensity identified in lab studies is universal or pan-human and this means the trait or propensity evolved for adaptive reasons in the ancestral past. The problem with most such studies is that the test subjects are highly derived or WEIRD: “white, educated, industrialized, rich, democratic.” It is exceedingly odd to infer, based on studies of weirdos, that traits or propensities are human universals. This is especially true when it comes to sex preferences, which are notoriously malleable and strongly conditioned by culture.

A recent PNAS study examined allegedly universal or “ancestrally evolved” sex preferences using test subjects from a wide variety of cultures. The findings, unsurprisingly, are significantly at odds with those that dominate headlines here in the West:

It is a popular assumption that certain perceptions—for example, that highly feminine women are attractive, or that masculine men are aggressive—reflect evolutionary processes operating within ancestral human populations. However, observations of these perceptions have mostly come from modern, urban populations. This study presents data on cross-cultural perceptions of facial masculinity and femininity. In contrast to expectations, we find that in less developed environments, typical “Western” perceptions are attenuated or even reversed, suggesting that Western perceptions may be relatively novel.

A large [evolutionary psychology] literature proposes that preferences for exaggerated sex typicality in human faces (masculinity/femininity) reflect a long evolutionary history of sexual and social selection. This proposal implies that dimorphism was important to judgments of attractiveness and personality in ancestral environments. It is difficult to evaluate, however, because most available data come from large-scale, industrialized, urban populations. Here, we report the results for 12 populations with very diverse levels of economic development. Surprisingly, preferences for exaggerated sex-specific traits are only found in the novel, highly developed environments. Similarly, perceptions that masculine males look aggressive increase strongly with development and, specifically, urbanization. These data challenge the hypothesis that facial dimorphism was an important ancestral signal of heritable mate value.

These findings militate in favor of methodological caution. There is also a large evolutionary psychology literature which asserts that allegedly universal cognitive traits give rise to and sustain “religious” beliefs. Most of these studies are based on tests of weirdos. Until these findings are replicated and confirmed cross-culturally, we should be cautious.


Did you like this? Share it:

3 thoughts on “Evolving Methods

  1. GregJS

    Titillating topic. I mean the fact that studies on WEIRDos keep turning out to be so off – at least as far as establishing human universals go. So, as someone not very plugged into the academic world, I have to wonder: How far does this go? Has anyone collected a large number of these kinds of studies (debunking WEIRDness as universal) in a single volume? And how deeply has the understanding that WEIRD cultures might not represent universal traits penetrated the academic-scientific establishment?

    It’s fascinating – and a bit disconcerting – to think that my image-idea of what makes an attractive mate is so highly culturally conditioned. I guess I like to think of that as one of the few remaining aspects of my self that is still more or less “primal,” “natural” and so on. Oh well. Then again, it’s not so surprising that the extreme versions of masculinity and femininity in our culture aren’t all that natural. After all, how long could the sorts of women we think of as “sexy” survive in a hunter-gatherer world? And how well could the kinds of “macho” men we think of as masculine survive in an egalitarian, intensely cooperative, sharing culture?

    You’ve posted on similar topics a few times since I found your blog, Cris, and have really enjoyed them. And I hope your more frequent postings are a sign that your West Nile virus is easing up?

  2. Cris Post author

    Greg, I’m not aware of any volume of collected papers (or single-author monograph) that is oriented around the hypothesis that WEIRD subjects are not universal exemplars of humanity, or which surveys tests for traits using non-WEIRD subjects. The instant classic paper on the problem with WEIRD test subjects only appeared in 2010, which means there has not been much time to propose cross-cultural research, obtain grants for what is probably expensive research (requiring lots of travel), and publish confounding results. The results will probably just trickle in over the next decade.

    As for your well-stated question — “How well could the kinds of macho or aggressive men we think of as masculine survive in an egalitarian, intensely cooperative, sharing culture [i.e., a hunter-gatherer society]?” — the probable answer is: “Not well.” In fact, today I was just reading an article in Science which discusses a recent symposium on the possibility that the major shift in human evolution, which can be seen both anatomically and in symbolic artifacts — may be the result of domestication, particularly of males. Here are the relevant excerpts:

    Researchers at the symposium proposed that something similar happened as human ancestors began to live in closer quarters, relying more on each other and on wider social networks to survive. By favoring more tolerant, less antagonistic individuals, natural selection reshaped both our behavior and our appearance. “The hypothesis that humans may have domesticated themselves … has the potential to solve many of the long-standing problems of human evolution,” says linguist Robert Kluender of the University of California, San Diego.

    All of these changes tend to make male faces look more like female ones, Robert Franciscus noted at the meeting, and are linked to lower testosterone levels. He and his colleagues proposed that selection for higher levels of social tolerance led to lower levels of testosterone and stress hormones, especially in males, and thus facial feminization. Studies of dog DNA have shown that the genes that regulate aggression affect development of facial shape, he reported at the meeting.

    In his talk, Richard Wrangham argued that natural selection triggered just such a process of delayed development and reduced aggression in humans. As social ties became more important to survival, Wrangham thinks, human ancestors may have inflicted the same kind of capital punishment, weeding out males who acted with intense and confrontational aggression. This doesn’t mean that humans are not “a dastardly species,” capable of war and torture, he noted, only that selection favored males who could work together, whether for peaceable ends or to carry out “low-arousal” or coalitional aggressive acts such as war.

    So much for macho men and assholes.

  3. GregJS

    Reminds me of the argument made by Christopher Boehm in Moral Origins about how hunter-gatherer groups would have de-selected a-holes. Unfortunately, modern life seems to have introduced a whole (a-hole) new set of incentives, with the expected results…

    Didn’t realize the WEIRD idea was so new. Presumably means even much of the most recent research still has these sorts of flaws.

Leave a Reply