We have an exciting press release from the University of Texas! Human evolution has been demonstrated by psychologists! It’s titled Men’s Preference for Certain Body Types Has Evolutionary Roots. Try reading it critically, though, and you discover it’s yet another set of bad studies overinterpreted by evolutionary psychologists.
Why is it always a study that verifies that men like to judge women’s bodies, with the conclusion that this has deep evolutionary significance? They do a good job of gussying it up with sciencey sounding rationales, I will say that for them. They’re looking specifically at the curvature of the spine in the lower back, and how well it projects women’s butts backwards.
“This spinal structure would have enabled pregnant women to balance their weight over the hips,” Lewis said. “These women would have been more effective at foraging during pregnancy and less likely to suffer spinal injuries. In turn, men who preferred these women would have had mates who were better able to provide for fetus and offspring, and who would have been able to carry out multiple pregnancies without injury.”
They say that the optimum curvature of the lumbar spine is 45°. OK, let’s just accept that for a moment. Do they have evidence that having a curvature of 44° or 46° actually affects women’s reproductive ability over their lifetime? Do they have evidence of even one woman who has decided to have one less child in her life because she has a hard time foraging for food with her slightly less curvy spine? Do we have an instance of one man deciding to marry and have children with a woman because her spine looks like it would qualify her for some quality prolonged turnip-picking time?
I am exasperated at the weakness of their premise, but I am appalled at the nature of their research to test their hypothesis. They did two studies.
About 100 men rated the attractiveness of several manipulated images displaying spinal curves ranging across the natural spectrum. Men were most attracted to images of women exhibiting the hypothesized optimum of 45 degrees of lumbar curvature.
Approximately 200 men were presented with groups of images of women with differing buttock size and vertebral wedging, but maintaining a 45.5-degree curve. Men consistently preferred women whose spinal curvature was closer to optimum regardless of buttock size.
Asking a bunch of college men (probably the usual collection of Psych 101 students) to look at pictures of women’s asses is not the way to test that idea. How about these experiments instead?
Survey a group of women field workers for back pain, or for health-related absences, and quantify the shape of their lower spine.
Examine a cohort of recently married women, and a cohort of unmarried women, and compare their spinal curvature. Is it actually a significant factor in mate choice?
Examine hospital records for patients who had difficulty in childbirth. Correlate that with spinal shape.
Unfortunately, those kinds of studies are hard to do; gathering the data is non-trivial, and when you do get it, you’d no doubt discover that there a whole lot of factors other than the shape of their asses that play into the physiological stresses of labor, mate choices, and decisions about having children, and you wouldn’t get the nice, simple-minded answers you’d get from asking a bunch of 19 year olds what shape of ass they like…and which will generate a nicely consistent set of responses conditioned by contemporary pop culture. And then, of course, the investigators will ignore the influence of culture so they can make sweeping statements about biology.
“What’s fascinating about this research is that it is yet another scientific illustration of a close fit between a sex-differentiated feature of human morphology — in this case lumbar curvature — and an evolved standard of attractiveness,” said the study’s co-author David Buss, a UT Austin psychology professor. “This adds to a growing body of evidence that beauty is not entirely arbitrary, or ‘in the eyes of the beholder’ as many in mainstream social science believed, but rather has a coherent adaptive logic.”
Christ. I can concur with the idea that we have a biological preference for some features of our mates: symmetry is a common one, as is general health, and you know, it’s not that far-fetched that we might avoid mating with individuals who show signs of being infested with parasites. But focusing on single parameters like the exact degree of curvature of part of the spine, and insisting that we’re hard-wired in some way to recognize its adaptive value, is incredible bullshit. Especially when the investigators haven’t actually demonstrated the adaptiveness of the feature in question.
And if standards of beauty have an adaptive basis, how does one explain how they vary over time and in different cultures? How does one handle the fact that different men have different standards, so what is beautiful to one may be less so to someone else? How do we account for the fact that women society judges beautiful don’t all look alike?
Easy. Just claim it’s the product of evolution, therefore these guys are right.
This morphology and men’s psychological preference toward it have evolved over thousands of years, and they won’t disappear over night.
“This tight fit between evolutionary pressures and modern humans’ psychology, including our standards of attractiveness, highlights the usefulness that an evolutionary approach can have for expanding our knowledge not just of the natural sciences, but also the social sciences,” Lewis said.
Gaaaah. You can’t just declare that men have had the same psychological preferences over thousands of years on the basis of a survey of contemporary male American college students! The conclusion is unsupported by the evidence! You also can’t just say that evolution would drive the shape towards some kind of engineering adaptive ideal — these are psychologists, have they never heard of superstimuli? And as psychologists, how can they so blithely dismiss the effects of common cultural experiences?
Fucking evolutionary psychologists. They really don’t help my blood pressure at all.