The evolution of same-sex attractions: Parental and intimate partners' reactions to deviations from exclusive heterosexual orientation

A considerable portion of the population experiences same-sex attractions. One possible factor that accounts for this phenomenon is that the selection pressures, coming predominantly from parents and intimate partners, exercised on sexual orientation in ancestral human societies had been weak. Based on this evolutionary framework, three hypotheses are derived and tested: First, it is hypothesized that men are less distressed than women by the same-sex attractions of their opposite-sex partners. Second, it is hypothesized that parents are less distressed by the same-sex attractions of their daughters than of their sons. Finally, the hypothesis is tested that the distress of intimate partners and parents over the sexual attractions of their mates and children respectively, is contingent upon the degree of the same-sex attractions: The more these deviate from exclusive heterosexual orientation, the stronger the reactions will be. Evidence from two independent studies finds support for all three hypotheses. These findings are applied in understanding the prevalence of same-sex attractions in contemporary populations.