Male aggressiveness as intrasexual contest competition in a cross-cultural sample

Sexual selection favors traits that increase mating and, thus, reproductive success. Some scholars have suggested that intrasexual selection driven by contest competition has shaped human male aggression. If this is the case, one testable hypothesis is that beliefs and behavior related to male aggression should be more prevalent in societies where the intensity and strength of sexual selection is higher. Measured by factors such as (a) the presence and scope of polygyny; (b) the number of same-sex competitors relative to potential mates, and (c) the amount of effort males are available to allocate to mating. Using Bayesian item response models with imputation and data from 78 societies in the Standard Cross-Cultural Sample, we found robust support for this hypothesis when using variables related to male aggression. We ruled out some potential alternative explanations by controlling for geographic region and confounding variables such as political complexity and warfare.