Women's Orgasms Exist Because...

Turns out there is a unique reason for the female orgasm... but nobody knows what it is yet. The latest foray into female ecstasy involved asking about 10,000 pairs of opposite-sex siblings and twins about their sexual habits. The upshot: Most of the girls had no similarity with their boy counterparts in terms of susceptibility to orgasm. Scientists in Australia and Finland say this means that the female orgasm serves a unique evolutionary purpose, New Scientist reports.

Why? One popular theory is that female orgasms are an evolutionary by-product from the male—you know, like nipples are on men. If boy-girl siblings and twins had a similar susceptibility to orgasm, that would have established a genetic male-female connection and bolstered the by-product theory. So if this study is accurate—and not all experts are on board—then scientists can return to other theories, like the notion that orgasms give gals a reproductive boost. (One professor tried to teach his students about female orgasms with a live demonstration.)