Sorry Sir Mix-a-Lot: Men prefer spinal curvature, not big butts


Step aside Sir Mix-a-Lot, just because a new study on The University of Texas at Austin discovered that men’s preferences for ladies with “buns” on their curved backside connects with prehistoric influences.

Published in Evolution and Human Behavior, men prefer women having a “theoretically optimal angle of lumbar curvature”-or a 45.5 degree curve from back to buttocks-in their mate.

“This spinal structure might have enabled women that are pregnant to balance their weight within the hips,” said David Lewis, UT Austin alumnus and Bilkent University psychologist. “These women could have been more efficient at foraging during pregnancy and less likely to suffer spinal injuries. In turn, men who preferred these women would have had mates who have been better able to offer fetus and offspring, and who’d have been in a position to execute multiple pregnancies without injury.”

The first had 100 men rate the attractiveness of multiple images displaying manipulated spinal curves ranging across the natural human spectrum. Looking at the vertebral wedging, a fundamental spinal feature that can influence the bend in women’s lower backs, researchers discovered that men were most attracted to the images of women with the 45 degree lumbar curve.

Women with (a) less vertebral wedging in the third-to-last lumbar vertebra (modal L3 depicted), and (b) greater wedging, producing a more acute angle of lumbar curvature. (Credit: The University of Texas at Austin)

The second study took research a step further, asking whether men preferred this 45 degree angle since it indicates a larger buttocks or just because of the spine angle itself. Two hundred men were given groups of images of women with varying buttock size and vertebral wedging, but all with the 45.5-degree curve. Men consistently preferred ladies who possessed the perfect spinal curvature, it doesn’t matter how big their buns were.

This is really a schematic of a complete number of stimuli. (Credit: The University of Texas at Austin)

“This enabled us to conclusively reveal that men prefer women who exhibit specific angles of spinal curvature over buttock mass,” study’s co-author Eric Russell, visiting researcher from UT Arlington stated.

“What’s fascinating about this scientific studies are that it is yet another scientific illustration of a detailed fit from a sex-differentiated feature of human morphology-in this example lumbar curvature-and an evolved standard of attractiveness,” said study co-author David Buss, a UT Austin psychology professor. “This contributes 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 includes a coherent adaptive logic.”

Sir Mix-a-Lot disagrees, however, offering his?rebuttal to all of us on Twitter.

@redorbit @Abbey4160 whatever creates the desired effect is cool beside me. ??

– Sir Mix-A-Lot (@therealmix) March 21, 2015

So ladies (yeah?), that you can do side bends or sit ups, but this evolutional stance won’t be changing for some time. However, studies like these expand our approach and knowledge for both natural and social sciences-it’s a win-win, no?