Why Guys Love Round Butts

Baby got back: women with curvy behinds made better nomadic child-bearers - which is why guys love round butts today, argues a new study from the University of Texas.

You’ve probably never thought about “lumbar curvature” or “vertebral wedging.” But the study authors have. And their research shows men tend to go gaga over a woman with the type of spine curvature that makes her butt seem to pop out or protrude.

If you’re like the average man, you’re especially attracted to a woman with a spine that curves roughly 45 degrees above the top of her butt, the research shows.

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Why? “This degree of curvature would have enabled ancestral women to shift their center of mass back over their hips during pregnancy,” says study coauthor Dr David M.G. Lewis.

Back in hunter-gatherer times, human beings were constantly on the move. Staying still was a death sentence. So women who could keep walking long distances even while very pregnant had an advantage in terms of reproduction and survival.

Lewis says a 45-degree lumbar curvature allows a woman to carry the weight of her unborn baby in a way that makes her less vulnerable to spinal injuries than women with more or less curvature. Thousands of years ago, this would have helped her to keep moving and foraging during the later stages of pregnancy - a huge plus, Lewis says.

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Apparently modern man hasn’t lost his taste for curvaceous, baby-bearing derrieres, this research suggests.