More evidence shows that humans are not naturally monogamous

A review by Florida Atlantic University researchers Todd K. Shackelford and Aaron T. Goetz has lent support to the growing body of evidence that humans are not naturally monogamous.

Washington, May 9 : A review by Florida Atlantic University researchers Todd K. Shackelford and Aaron T. Goetz has lent support to the growing body of evidence that humans are not naturally monogamous.

Shackelford said that the review showed that there is competition between males not only occurs before mating, but also after, and that they have evolved to deliver their sperm more effectively to females with multiple partners.

"Although many people are familiar with the idea of animals competing for mates before sex occurs, through mating displays such as bright feathers or butting antlers, we are finding more evidence that there is also competition after mating occurs," he said.

This competition however, is for fertilization.

"An alternative way of thinking about it is that there is not only competition between males for mates, but competition between males for fertilization," Shackelford added.

The research presented in the review covers physical adaptations, including penis shape and style of intercourse, as well as behaviour in response to perceived infidelity that all serve to increase the success of fertilization.

"The studies have shown that when partners are separated for periods of time, males are more likely to arouse easily, produce more sperm, and even rape their partners," says Shackelford.

However, the researchers insist that this does not mean that women are promiscuous by nature, but it is evidence that humans are not naturally a monogamous species.

They also point out, however, that females are not passive partners in the sexual relationship.

"Although this review focused on male adaptations, sexual conflict between males and females produces a co-evolutionary arms race between the sexes, in which an advantage gained by one sex selects for counter-adaptations in the other sex," Shackelford said.

The review appears in the journal Current Directions in Psychological Science.

ANI