According to a new paper, published on Thursday, January 14th, in the Journal of Personality and Social Psychology, women appear to pick up on subconscious cues that alert them to other women nearby that are ovulating.  In turn, this leads them to become instinctively protective of their mates.

Psychologists from Arizona State University conducted four studies with 478 heterosexual women who were either engaged or married.  The research found that participants were more likely to try to create distance between other women and their partners when the other women in question were ovulating.

The women in the study were not told that the other females were ovulating.  Instead, the partnered women appear to have instinctively been able to register this information.

The conclusion that the doctors have come to?

Humans seem to be subconsciously aware of various physical cues that indicate when women are fertile.

Further, the study also found that women become even more protective of their mates when the potential competing females are more attractive.  In addition to attempting to create distance between their men and potential competitors, the research also found that women employ other tactics to keep their men close.

“Specifically, women with desirable partners reported that they would show increased sexual interest in their partners after viewing a high-fertility target, regardless of how attractive that target was.”

It should be noted that this sort of mate-guarding appears to be in effect regardless of whether the competing female is a total stranger or a closely trusted friend.

All of that being said, the researchers noted that these tactics are not always effective.  Some women are simply better at swiping men than other women are at protecting them.

If you've ever lost a boyfriend to another woman, you can probably relate.

But don't beat yourself up about it.  Male primal instincts play a part as well.

Research has also indicated several times over that men possess an innate, built-in desire to mate with as females as possible.  Some guys are just better at repressing those primal urges than others.