In evolutionary psychology, jealousy is explained as a result of selection pressures maximizing our reproductive capacity. Previous studies have shown gender differences in the perception of jealousy; men generally demonstrate higher response to sexual infidelity (SI), whereas women to emotional infidelity (EI).
Studies on jealousy between homosexual partners showed, that gay men tend to be more sensitive to EI, whereas lesbians expressed more concerns regarding SI. These studies suggest that the type of jealousy might depend on the sex of respondent's partner.
The aim of this study was to explore the experience of jealousy in heterosexuals and homosexuals using an online survey, and to examine whether sexual/emotional jealousy differs depending on a respondent's partner's sex. The study involved 286 participants, 137 men (mean age 27.8, SD = 5.88) and 149 women (mean age 25.07, SD = 5.32), who were in a relationship.
All respondents completed a set of anonymous questionnaires about partner's jealousy (PJ) (Anticipated Sexual Jealousy Scale; Scale for Three Types of jealousy). To compare the differences in the type and extent of PJ between heterosexuals and homosexuals we performed one-way ANOVA and Fisher test.
Women were more jealous then men in all categories of PJ: heterosexual women were more jealous than heterosexual men (p = 0.005) and homosexual women were more jealous than gay men (p <0.001). Men in a relationship with a woman (versus men in a relationship with a man) showed higher SI jealousy (p = 0.001), and similarly, women in a relationship with a woman (compared to women in a relationship with a man) also reported higher SI jealousy (p = 0.001).
Women in a relationship with a man (versus women in a relationship with a woman) showed higher jealousy to EI (p <0.001). In men we found no difference in the level of experiencing PJ in response to EI.