Using an evolutionary framework, we generated hypotheses about the content of men’s and women’s deceptions toward their same- and opposite-sex friends. In Study 1 (N=359), we asked men and women to tell us, via open-ended responses, what they deceived their male and female friends about. In Study 2, we compiled and expanded upon those responses and then asked two samples of young adults (N=389, N=303) to report how often they engaged in each type of deception towards their male and female friends. Analyses revealed consistent support for several hypotheses, including that young people would (1) deceive same-sex friends more often than opposite-sex friends about mating rivalry; (2) deceive opposite-sex friends more often than same-sex friends about romantic interest or disinterest; and (3) deceive female friends more often than male friends about their friends’ appearance. Analyses revealed partial support for the hypotheses that (1) men more often than women would deceive their opposite-sex friends about feelings of romantic interest; and (2) women more often than men would deceive opposite-sex friends about romantic disinterest. Future research could focus on investigating the motives (e.g., fear of rejection) and circumstances (e.g., relationship status) tied to various forms of deception.
