Biologists have long known that sexual selection is a force that can mould the evolution of a species. Occasionally adaptations developed by males and females are at conflict with one another.
Credit: MIT
But, perhaps the most novel aspect of these results is “that females have the upper hand on a trait that is often assumed to be under significant male control,” said Mazzi.
Further tests showed that when females were allowed to interact freely with males, copulations last much less than when females were prevented from resisting. In fact copulations lasted 50% longer, the researchers found. This “implies that females gain from copulations that do not exceed a certain optimum duration,” she said.
Gordon Gallup, an evolutionary psychologist from the University at Albany, in New York, USA, says this study is “very interesting” and consistent with a variety of other strategies males adopt to ensure paternity in those species with promiscuous females.
He adds that there is some evidence that the “human penis evolved to displace rival male semen from the woman's reproductive tract and enable men to substitute their semen for those of their competitors.”
Follow Cosmos on Twitter!
twitter.com/cosmosmagazine
