The female orgasm has always been one of science's great mysteries—but now, two evolutionary biologists have offered a new explanation that might help shed light on its true purpose.
In a study published in the Journal of Experimental Zoology, Mihaela Pavlicev of the University of Cincinnati College of Medicine and Günter P. Wagner of Yale University argue the female orgasm originated over 150 million years ago as a way for mammals to release eggs for fertilization after sex.
"For orgasms, we kept it reserved for humans and primates," Pavlicev told The New York Times. "We didn't look to other species to dig deeper and look for the origin."
As the biologists point out, while human females are on an ovulatory cycle, releasing an egg once a month, there are other female mammals that only release an egg after they've mated with a male. By studying the history of early mammals, Pavlicev and Wagner concluded humans' early ancestors likely also relied on sex to trigger ovulation before they evolved ovulatory cycles.
According to the study, early female mammals developed the clitoris inside of the vagina so when mating, it would trigger the release of the egg. This way, the animal could have a higher chance of reproduction with every sexual encounter, and they'd be less likely to waste an egg. But as the Times explains, as some mammals began to evolve to live in social groups, mating became much more regular, and as a result, these mammals eventually evolved to have ovulatory cycles. Because of this, the clitoris also evolved and moved outside of the vagina, since orgasm was no longer necessary to help females become pregnant.
While the theory doesn't exactly explain why females have orgasms today, both biologists hope it helps foster a dialogue in the science community and encourages further exploration on the topic.
For now, its less evolutionary purpose seems like a good enough reason for its existence to me.
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This article originally appeared on Cosmopolitan.com. Minor edits have been made by the Cosmo.ph editors.