Scientist may have uncovered the evolutionary mystery behind why women have evolved to have orgasms – knowing well that they play no obvious role in human reproduction.
Scholars at Yale and the Cincinnati Children’s Hospital have revealed that the female orgasms may once have had an extremely important purpose.
A recent research by the scholars on the debated topic which goes as far back as Aristotle revealed that female orgasms aid human reproduction by stimulating ovulation via the production of two hormones in the brain, called prolactin and oxytocin.
Mostly, research dedicated to finding out the point of the female orgasm has focused on humans. By looking at other mammals, scientists now believe it does have a part to play.
“Prior studies have tended to focus on evidence from human biology and the modification of a trait rather than its evolutionary origin,” said Gunter Wagner, from Yale University. He and Mihaela Pavličev from Cincinnati Children’s Hospital have now published a study on the role of the female orgasm in the journal JEZ-Molecular and Developmental Evolution.
In the journal, the team wrote: “Aristotle noted the main obstacle in explaining the role of female orgasm: human females can conceive without it … Equally suggestive is the statistics, showing human female orgasm during sexual intercourse is uncommon, in particular without additional clitoral stimulation.”
The Mirror quoted the journal as saying that in many mammals, the production of these hormones acts as a trigger for the ovaries to release an egg.
In some species, ovulation is actually induced by the male – in other words, the female only produces an egg after having an “orgasm”.
Although, these days, the human ovarian cycle does not depend on sexual activity, the scientists believe that human reproduction may once have operated this way.
It was only later that “cyclical” ovulation evolved – otherwise known as the menstrual cycle – and the female orgasm became superfluous from a reproductive perspective.
The scientists said that the evolutionary shift from “induced ovulation” to “cyclical ovulation” may also have prompted the relocation of the clitoris from inside the vagina to outside.
“This anatomical change made it less likely that the clitoris receives adequate stimulation during intercourse to lead to the neuro-endocrine reflex known in humans as orgasm,” they said.
Before you get too depressed, the scientists added that the evolutionary ancestor of the orgasm probably wasn’t what we think of as an orgasm today.
“It is important to stress that it didn’t look like the human female orgasm looks like now,” said Mihaela Pavlicev, who helped lead the study.
“We think that [the hormonal surge] is the core that was maybe modified further in humans.”
Well that’s something at least.
This study appeared in the August 1 edition of the journal JEZ-Molecular and Developmental Evolution.