Contest Competition in Men

In this chapter, we explore how men's phenotypes, including their psychologies, have been shaped by contest competition, a form of sexual selection involving the use of force or threat of force to exclude same-sex competitors from mates. We first evaluate the intensity of sexual selection in men, finding evidence of a positive and moderately strong relationship between men's mating success and reproductive success, and between each of these and putative sexually selected traits. Next, we use a comparative and functional approach to evaluate how men's phenotypes were shaped specifically by contest competition. Contrary to inferences made from our negligible canine size and modest body mass dimorphism, we find that human beings are sexually differentiated along dimensions expected of a species with an evolutionary history of male contests, and that men's phenotypes show evidence of design for contest competition. Finally, we explore how contests may have contributed to male mating and reproductive success over human evolution.