89 Sex Differences and Intrasexual Variation in Competitive Confrontation and Risk Taking: An Evolutionary Psychological Perspective

An evolutionary psychological perspective can be of assistance to researchers investigating psychophysiological mechanisms, by identifying the sorts of contingent responses that are likely to have been favored by selection and by suggesting hypotheses about the ways in which these mechanisms respond to social factors and to cues of future prospects. We first introduce the evolutionary psychological perspective, with emphasis on the concepts of adaptations, sexual selection, and life history. We then argue that homicide can be treated as an assay of the intensity of competition among men, and review some relevant findings. Finally, we review evidence that testosterone modulates risk taking, mating effort, and willingness to engage in dangerous confrontational competition, in light of the proposition that social, endocrinological, and other controls of such behavior have been shaped by a history of sexual selection, and discuss the costly signaling explanation for testosterone-dependent display attributes. We conclude that perceptual and cognitive mechanisms subserving the interpretation of social situations and decision making must be functionally integrated with endocrine, immune, and other physiological systems to produce coordinated and subtly modulated responses to cues of the utility of competitive and aggressive actions, at least as they would have paid off in fitness in ancestral environments.