Funny thing about dogma — no matter who’s espousing it, they’re probably wrong. And science is by no means immune.
Take, for example, a nifty bit of evolutionary dogma so often repeated that it’s now assumed correct: sexual preferences for certain body types exist because we’ve evolved these desires to maximize our chances of mating with the most fertile or healthiest partner. Generally this means slim and fit, and tall if you’re a man.
The logic underlying this belief seems solid enough, and there’s evidence supporting it via studies conducted in Western nations. Ah, but there’s the rub. Mind Hacks points to a new study in the journal Biology Letters showing that this alleged universal preference does not exist in the least among the Hadza people, a hunter-gather tribe from Tanzania.
Quoting from the Science News review of the study:
Hadza marriages don’t tend to consist of individuals with similar heights, weights, body mass indexes, body-fat percentages or grip strengths… Neither do Hadza couples feature a disproportionate percentage of husbands taller than their wives, as has been documented in some Western nations.
Almost no Hadza individuals mention height or size when asked to explain what makes for an attractive mate, Rebecca Sear and Frank Marlowe (the study authors) add.
Worth noting, this doesn’t mean that people do not generally seek healthy, fertile marriage partners. Overall, they do. But, quoting Rebecca Sear: “I suspect there may not be a preference for one particular signal of health in mates across every population.”
Western studies on this topic are often conducted using college students. Since most research happens at universities, students are the plentiful and cheap population of choice for researchers. Offer them extra credit and you’ve got an eager group of study participants ready to go. The problem is that college students at Western universities are in many ways an atypical group. Quoting again from Science News (via Mind Hacks):
Sear and Marlowe criticize evolutionary psychologists who have argued that physical size influences mating decisions in all societies. That argument rests largely on self-reports of Western college students and analyses of personal advertisements in U.S. newspapers for dating partners, they say.
This isn’t the first time the Hadza have been used in research to undermine evolutionary sex preference dogma. In a previous study, Hadza males were shown pictures of females with varying sized waist-to-hip ratios. Not only did they not show preference for low ratios, but they didn’t even consider the ratio in their determination of attractiveness.