Most women probably don’t make a connection between how many male friends they have and how much sex they’re having in their relationship. But a new shows, for evolutionary reasons, this has a direct influence on how much more. The research, which was recently published in the Journal of Comparative Psychology, shows a man who considers his partner attractive to others has more sex with her. Whether they know it consciously men perceive other males in their partner’s life as sexual threats.
Evolutionary psychologists call it sperm competition, which means a man tries harder to impregnate his partner if he thinks he has competition. These men feel jealousy, consciously or not. Researchers found couples had more sex when the woman had greater interaction with other men. The more males in his woman’s life the more he initiates sex.
“We predicted this because there’s a huge amount of nonhuman studies showing male animals, for example mice or rats, are more interested in sex when they see the female partner interacting with other males. They don’t have to see them having sex. It’s just the presence.”
This pattern is seen from mice to birds to insects. Since the competitive urge makes itself felt at the brain’s lower levels, it works the same in humans. It unlikely men know they’re acting out of Darwinian jealousy when they initiate more sex as a result of men in her life.
The porn men watched when providing semen samples shows this. If you ask one man to provide a masturbatory ejaculate while watching a scene of multiple men having sex with one woman, and ask another man to do it while watching a scene of one man having sex with multiple women, the quality of the ejaculate is higher!