New research provides evidence that culture can moderate women’s reactions to infidelity with opposite-sex and same-sex partners. The study, published in the journal Human Nature, compared women’s reactions to heterosexual and homosexual infidelity in Canada, Samoa, and among the Istmo Zapotec, an indigenous peoples living in Mexico.
“It’s often assumed that non-heterosexual people are on the outside looking in when it comes to the heterosexual ‘mating market,’ but this doesn’t always ring true,” said study author Scott W. Semenyna of the University of Lethbridge
“Spending time in non-Western cultures often sparks research ideas, and it’s rather common for men in places like Samoa to engage in short-term sexual liaisons with fa’afafine—a non-binary gender identity adopted by Samoan males who are feminine and attracted to men. The same thing happens in the Istmo Zapotec region of southern Mexico, where it isn’t uncommon for men to have sex with muxes, a gender/sexual orientation category similar to fa’afafine.”
“In both cultures, these men appear to be mostly heterosexual or, to a lesser extent, bisexual. Plenty of research examines people’s responses to heterosexual infidelity, but we wanted to build on the much smaller literature looking at same-sex infidelity, extending this research in non-Western cultures,” Semenyna explained.
The researchers asked women from all three cultures how upset they would be if their male partner had a one-time sexual encounter with either a woman or another man. The sample included 1,041 Canadian women, 113 Samoan women, and 263 Zapotec women.
Semenyna and his colleagues found that Canadian and Samoan women tended to be more upset about heterosexual infidelity than homosexual infidelity. Istmo Zapotec women, on the other hand, tended to be more upset by homosexual infidelity.
“Same-sex infidelity can and does happen, partly as a result of sexual competition between the sexes, which is fairly common in places like Samoa and the Istmo Zapotec. Canadian women were generally more upset by the thought of heterosexual infidelity. An even larger difference was found in Samoa, where some women were hardly upset when asked to imagine their partner being unfaithful with a fa’afafine, but dismayed imagining infidelity with a woman,” Semenyna told PsyPost.
As one Samoan woman told the researchers, “With a woman, one might turn into another and another,” but with a fa’afafine, “I don’t mind because the man goes and comes back.”
“Women’s stronger reaction to heterosexual infidelity is likely related to things like the risk of pregnancy and being abandoned for another woman,” Semenyna said. “This general pattern can be modified if women believe that same-sex infidelity indicates that their partners have a pervasive (but hidden) same-sex preference themselves, which would spell disaster for a heterosexual relationship. This is illustrated by women in the Istmo Zapotec being slightly more upset by the thought of their partner having a one-night stand with a muxe compared to another woman.”
In another study that examined perceptions of mate-poaching behavior, published in the Archives of Sexual Behavior, Semenyna and his colleagues found that Canadian women tended to be more trusting of gay men than other women and Samoan women tended to be more trusting of fa’afafine than other women. Zapotec women were equally distrustful of women and feminine muxe, but placed greater trust in masculine muxe.
As far as limitations go, Semenyna noted that “we don’t yet know how common same-sex infidelity is vis-à-vis heterosexual infidelity, or what individual differences (personality, past experiences, etc.) might influence women’s stronger reaction to one type over the other.”
“Although same-sex infidelity is likely rarer in Euro-American cultures, we don’t know how much this varies globally. We also know very little about mate competition between males and females for the same romantic/sexual targets, but it clearly happens and impacts human mating psychology in largely unexplored ways,” Semenyna said.
“Growing knowledge of diversity in sexual orientation and gender expression should feed back into our theoretical models,” Semenyna added. “This will adjust the lenses used to understand opposite-sex interests and behavior, which make sense from an evolutionary perspective, and how we interpret same-sex interests or behavior, which don’t dovetail as seamlessly with evolutionary perspectives on human mating. Cross-cultural models, like we used in our study, will be especially important in addressing these kinds of big-picture questions in psychology.”
The study, “Women’s Reaction to Opposite- and Same-Sex Infidelity in Three Cultures Data from Canada, Samoa, and the Istmo Zapotec“, was authored by Scott W. Semenyna, Francisco R. Gómez Jiménez, and Paul L. Vasey.