Men Are Totally Hardwired by Evolution to Prefer Curvy Women, Study Finds

A new University of Texas study has found that men express a clear preference for women who have a pronounced back-to-buttock curve.

After asking around 100 men to rank the attractiveness of images of various females, researchers found that men strongly preferred women with a back-to-buttock curve of 45.5 degrees, which they described as the “theoretically optimal angle of lumbar curvature.”

They theorized that, in ancient times, such an angle meant that women were more likely to carry out successful pregnancies.

“This spinal structure would have enabled pregnant women to balance their weight over the hips,” said researcher 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.”

Researchers conducted a second study to rule out if the spinal curvature preference was due to the buttock size rather than the spinal curvature angle itself. But they discovered that men repeatedly exhibited a preference for women with spinal-curvature angles closer to the optimum, even if the women had smaller buttocks.

“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,” Lewis added.

Read next: This App Alerts You When You’re Near a Spot Where a Woman Made History

Get The Brief. Sign up to receive the top stories you need to know right now.

Please enter a valid email address.

* The request timed out and you did not successfully sign up. Please attempt to sign up again.

Sign Up Now

An unexpected error has occurred with your sign up. Please try again later.

Check here if you would like to receive subscription offers and other promotions via email from TIME group companies.

You can unsubscribe at any time. By signing up you are agreeing to our Terms of Service and Privacy Policy.

Thank you!

For your security, we've sent a confirmation email to the address you entered. Click the link to confirm your subscription and begin receiving our newsletters. If you don't get the confirmation within 10 minutes, please check your spam folder.

Listen to the most important stories of the day.

Contact us at letters@time.com.