Friendship jealousy, which can be felt when a third-party individual threatens one’s friendship by becoming increasingly close with one’s own friend, may manifest differently based on the biological sex differences of those in involved. Indeed, new research published in Evolution and Human Behavior found that women were more jealous at the prospective loss of a best friend than men and that men were more jealous at the prospective loss of an acquaintance than women.
Friendship jealousy is distinct from other types of jealousy and other similar emotions. “Friendship jealousy is evoked by third-party threats to friendships (and not by the threatened loss of the friendship alone): When same-sex best friends simply stop engaging in friendship activities, the prominent felt emotion is sadness; in contrast, when same-sex best friends engage in those activities with new friends, the prominent felt emotion is friendship jealousy,” explained study author Jaimie Arona Krems and colleagues.
Further, friendship jealousy seems to act differently than romantic jealousy. Specifically, both men and women report feeling greater jealousy when their best friend spends more time with a same-sex other than with a new romantic partner.
“In terms of sex differences in friendship structures, females tend to form one or two very close dyadic friendships, whereas males tend to form looser multi-male friendship groups,” noted the researchers. Thus, they predicted that women might experience greater friendship jealousy for best and close friends compared to men due to the increased investment in women’s friendships.
To address this research question, the study authors re-analyzed data from two previous studies that examined friendship jealousy. From these studies, researchers obtained a final sample of 786 undergraduate participants. Each participant was asked to give the initials of four same-sex others in their daily lives: a best friend, two close friends who were not friends with the best friend, and an acquaintance.
Participants were then presented with several scenarios where they imagined another same-sex person becoming increasingly close with their best friend, close friend, or acquaintance. After each scenario, participants rated their emotional response including level of jealousy, anger, and sadness.
In general, women reported greater friendship jealousy than men. Further, both sexes reported friendship jealousy that was greatest at the potential loss of best friends and lowest at the potential loss of an acquaintance (compared to close friends, which was somewhere in the middle). Both sexes also reported more jealousy toward their best friend making new friends compared to their best friend getting a new romantic partner.
“We also found some—albeit not strong—support for the predicted sex differences in friendship jealousy over acquaintances, with men reporting somewhat greater friendship jealousy than women. This is consistent with the notion that much of men’s agonistic conflict—particularly intergroup warfare—is a numbers game, such that the value of even casual friends might be greater for men than for women. To the extent that friendship jealousy is calibrated to friend value for both sexes, this could explain men’s greater response to the prospective loss of same-sex acquaintances,” proposed the researchers.
Researchers followed up this study with another experiment looking at the potential effects of intergroup conflict. “The threat of intergroup conflict might enhance the possible costs of friend loss for men, and thus increase men’s (but not necessarily women’s) friendship jealousy,” the researchers predicted.
Participants were recruited on Mechanical Turk for a total sample size of 224 adults. The procedure was similar to the previous two studies. Participants were asked to imagine various friends becoming closer with another same-sex person; however, there were two different contexts participants were given. In the first context, the person was described as a “same-sex rival” and in the second, the person was described as being on a team with the participants’ friends. Participants then reported levels of jealousy and other related emotions.
Like in the first analysis, women reported overall greater friendship jealousy than men. However, context affected this relationship. Men reported more jealousy at the prospective loss of teammate friends to rival teams compared to rival individuals. On the contrary, women reported more jealousy at the prospective loss of friends to rival individuals compared to rival teams.
“In all, we still see that women report greater friendship jealousy at the prospective loss of friends than men do. But consistent with our reasoning, men’s friendship jealousy was uniquely enhanced in the context of intergroup conflict.”
The authors cite some limitations of this work. One is that this sample was limited to United States residing adults. Future work should look at cross-cultural differences and similarities in friendship jealousy.
The study, “Sex (similarities and) differences in friendship jealousy“, was authored by Jaimie Arona Krems, Keelah E.G. Williams, Laureon A. Merrie, Douglas T. Kenrick, and Athena Aktipis.