OBJECTIVES: Dominance and submissiveness represent strong sexual arousal stimuli for a considerable part of population. In contrast to men's sexual dominance and women's sexual submissiveness, the opposite preferences represent an evolutionary enigma. Here, we studied prevalence and strength of particular preferences in general population by Internet-trap-method. DESIGN: The subjects who clicked the banner displayed in the web interface of e-mail boxes were allowed to choose icons with homosexual or heterosexual partner of different hierarchical position. RESULTS: Dominant partner was chosen by 13.8% men and 20.5% women, and submissive partner by 36.6% men and 19.8% women. Homosexual partners were chosen by 7.3% men and 12.2% women. The response times for the submissive and dominant stimuli did not differ while for the equal-status stimuli were significantly longer, suggesting that part of subjects with equal-status preferences probably intentionally mask their natural interests. CONCLUSIONS: Large number of people who chose unequal sexual partner suggests that hierarchical status plays important role in human mating system.

Department of Anthropology and Human Genetics Faculty of Science Charles University Prague Czech Republic

Does Toxoplasma infection increase sexual masochism and submissiveness? Yes and no