We are interested in how people share information strategically to address mating rivalry. Previous research has shown that women are more likely to spread negative information about a woman’s sexual promiscuity when she is described as a potential mating rival compared to not (Reynolds et al., 2018). Here, we investigate how women’s and men’s reported likelihood of sharing information about a same-sex newcomer to their social group is influenced by describing the newcomer as attractive and flirting with their romantic partner (i.e., as a mating rival). We used information that would (1) harm primarily men’s reputation (e.g., being a coward), (2) harm primarily women's reputation (e.g., being promiscuous), (3) harm both sexes’ reputation (e.g., using drugs), and (4) enhance both sexes' reputation (e.g., being smart). As hypothesized, participants were less likely to pass along reputation-enhancing information when the newcomer was described as a mating rival. Both men and women were more likely to pass along both male-harming and female-harming information when the newcomer was described as a mating rival. Men were more likely than women to pass along male-relevant reputation-harming information and, contrary to our prediction, men were also more likely than women to pass along female-relevant reputation-harming information.
