ABSTRACT
Do biological factors contribute to sex differences in human behavior? Do they also lead to individual differences in masculinity and feminin ity? How can we answer these questions? There are a number of possi bilities. First, we can examine the results of experiments that probe the impact of sex hormones on animals’ nervous systems and sex-linked behavior. Second, we can study people who were exposed to unusual levels of sex hormones early in life because of genetic or hormonal ab normalities. Third, we can examine evidence on whether people’s lev els of sex hormones are related to gender-related behaviors, such as aggression, visual-spatial ability, and sexual orientation. And finally, we can contemplate tragic real-life events that provide information about the power of nature and nurture to influence gender-such as when a baby boy loses his penis because of a botched circumcision procedure and is subsequently raised as a girl.
