Spheres of Sexual Confl ict 21

Evolutionary confl icts pervade all of life. The coevolutionary arms race between males and females has equipped both sexes with mutually manipulative and defensive adaptations. These adaptations function to benefi t individual reproductive interests at the cost of the reproductive interests of opposite-sex mates and arise from evolutionary dynamics such as parental investment (unequal reproductive costs between the sexes) and sexual selection (unequal access to opposite-sex mates). Individuals use these adaptations to hijack others’ reproductive systems, psychological states, and behaviors—essentially using other individuals as extended phenotypes of themselves. Such extended phenotypic manipulation of sexual rivals and opposite-sex mates is enacted by humans with the aid of hormones, pheromones, neurotransmitters, emotions, language, mind-altering substances, social institutions, technologies, and ideologies. Furthermore, sexual confl ict may be experienced at an individual level whenever maternal and paternal genes are in confl ict within an organism. Sexual confl ict may be physically and emotionally destructive but may also be exciting and constructive for relationships. By extending the biological concept of sexual confl ict into social and cultural domains, scholars may successfully bridge many of the interdisciplinary gaps that separate the sciences from the humanities. Key Words: sexual confl ict, extended phenotype, arms race, parental investment, sexual selection, cultur