Ask a heterosexual man and woman about their reactions to their partners cheating, and you'd likely get two very different answers. That's according to a huge study on jealousy among people of different sexes and sexualities. Researchers at Chapman University polled some 64,000 people on how they'd react to hypothetical infidelity, and they found that while gay men and women, as well as bisexual men and women, didn't much differ in their feelings on the matter, heterosexuals did. Straight men, more often than women, found sexual infidelity to be the most disturbing kind, while straight women, more often than men, were most bothered by emotional infidelity—eg, their partners falling in love with another person, a press release reports.
"Heterosexual men really stand out from all other groups: They were the only ones who were much more likely to be most upset by sexual infidelity rather than emotional infidelity," says a researcher. And as Time reports, the findings held true regardless of factors like marital and parental status, income, and whether one had been cheated on in the past. (One caveat: Younger people were more bothered by sexual infidelity than older respondents, perhaps because sex plays a larger role in their lives, Time notes.) An evolutionary explanation for the phenomenon would hold that a man can't know for sure whether a child is his own, therefore men are concerned about sexual cheating. A sociocultural explanation would note that men are socialized to take pride in sexual ability, and a partner cheating suggests the man's talents are not so impressive. (We're not the only creatures who experience jealousy.)