Jealousy differs among men, women

Chapman University conducted the largest study to date on infidelity on nearly 64,000 Americans, and found that while heterosexual men were more likely than heterosexual women to be most upset by sexual infidelity (54 percent of men vs. 35 percent of women) and less likely than heterosexual women to be most upset by emotional infidelity (46 percent of men vs. 65 percent of women).

Participants imagined what would upset them more: their partners having sex with someone else (but not falling in love with them) or their partners falling in love with someone else (but not having sex with them).

Consistent with the evolutionary perspective, heterosexual men were more likely than heterosexual women to be upset by sexual infidelity and less likely than heterosexual women to be upset by emotional infidelity. Bisexual men and women did not differ significantly. Gay men and lesbian women also did not differ.

David Frederick, Ph.D., and lead author on the study said that heterosexual men really stood 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. The attitudes of gay, lesbian, and bisexual men and women have been historically understudied and under theorized in psychology, particularly in regards to tests of evolutionary perspectives.

The responses of men and women to the threat of infidelity range from intense pangs of jealousy to elaborate displays of attention to woo their partner back. Jealousy can also trigger harmful and violent behavior, so it was important to understand what were the most potent triggers of jealousy, said Dr. Frederick.

Factors such as age, income and whether people had children were unrelated to upset over sexual versus emotional infidelity. However, younger participants were notably more upset by sexual infidelity than older participants.

A total of 63,894 participants of ages 18-65 years completed the survey. On average, participants were in their late 30s.