Researchers revealed the evolutionary reason behind why men tend to prefer curvy women.
Men are believed to be programmed to be attracted to women with an "optimal" lumbar curvature of 45.5 degrees from back to buttocks, the University of Texas at Austin reported. A team of scientists believe this is because ancient women with these proportions were better able to withstand multiple pregnancies.
"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."
The researchers conducted two studies that looked at vertebral wedging (which can influence the curve of a woman's back) and whether or not men actually preferred this feature, as opposed to simply large buttocks. In the first study, 100 men were asked to rate the attractiveness of several manipulated images. The results showed men were most attracted to images of women who displayed 45 degrees of lumbar curvature.
"This spinal structure would have enabled pregnant women to balance their weight over the hips," said UT Austin alumnus and Bilkent University psychologist David Lewis. "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."
In the second study, about 200 men were shown different groups of women with differing buttock sizes and vertebral wedging. They found men still preferred women with a 45.5 degree curve, regardless of the size of their bottom.
"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 concluded.
The findings were published in a recent edition of the journal Evolution and Human Behavior.
