A 2012 paper in Evolution and Human Behavior by Leif Edward Ottesen Kennair and Mons Bendixen takes a much-needed evolutionary look at the issue of sexual harassment. They write in their paper:
While traditional social science theories have explained harassment as male dominance of females, the evolutionary perspective has suggested that sex differences in the desire for sex are a better explanation.
And their finding, in brief, was that an “unrestricted” sexuality “motivates people to test whether others are interested in short-term relations in ways that sometimes might be defined as harassment.”
The competing prediction suggesting that male dominance over females is the primary motivation for harassment was largely unsupported in this study. Not only was female harassment of males quite prevalent, so too was same-sex peer harassment. In addition, other competing social factors did not outweigh the importance of sociosexual orientation in explaining variations in sexual harassment for either of the sexes.
The main idea behind our predictions was the hypothesis that harassment is an unrestricted sociosexual style of behavior, aimed at testing out whether a potential sexual partner is available for a short-term sexual encounter, and that perceived harassment behavior to a large degree is motivated by a desire for sex. However, many instances of harassment in our study were cases of same-sex harassment. This may be understood from a similar perspective. It is an example of sexual surgency or dominance, and sexual competitiveness (Campbell, 2004). Thus, the logic of the evolved psychology of derogation (Schmitt & Buss, 1996) is relevant for understanding this behavior.
While more boys sexually harass and coerce than girls, both sexes commit sexual harassment and coercive acts. And while many different negative precursors and correlates have been suggested, it would seem that the main motive is an interest in short-term sex indicated by an unrestricted sociosexuality. This same characteristic also causes behavior that advertises an interest in sex, increasing the attraction of nonattractive partners. Furthermore, these individuals probably have an increased interest in sexual competition, thus both being subject to and partaking in same-sex derogation. Thus, an unrestricted sociosexual orientation is related to both harassing behavior and being a victim of harassment in high school.