Davies, Alastair P. C.

Although researchers agree that humans exhibit behavioral sex differences, there
remains controversy over whether these sex differences are socially constructed or
are the product of divergent evolutionary selection pressures on the psychologies
of men and women. Through four studies, this dissertation presents evidence that
behavioral sex differences have their origin in divergent evolutionary selection
pressures and that these sex differences lead to conflict between the sexes. The
first two studies investigate a type of sexual infidelity known as human mate
poaching. The third study investigates the use of physical attractiveness as a tactic
to persuade opposite-sex individuals. The fourth study documents expressions of
hypothesized evolved psychological sex differences and sexual conflict in the
lyrics of songs from hip-hop artists. The final chapter considers a social constructivist account for the origin of behavioral sex differences and argues that
an evolutionary psychological account has greater explanatory power.

Mate poaching occurs when an individual has sexual relations with the romantic partner of another. In Study A, I investigated the prevalence of mate poaching by presenting participants with questions whose devising was informed by a stricter definition of mate poaching than that employed by earlier studies. As expected, relative to participants in earlier studies, the current participants reported fewer experiences of mate poaching. In Study B, I investigated the likelihood that the benefits and costs of mate poaching will, respectively, motivate participants to poach or will deter them from doing so. Results indicated that for males and females to be motivated to poach, the attached individual must be more attractive than the unattached individual.