Unlike most other female primates, the human female may engage in intercourse at any time throughout the year. Some scholars have suggested that more or less continuous female sexuality may have created a serious problem: considerable sexual competition between males for females. It is argued that society had to prevent such competition to survive, that it had to develop some way of minimizing the rivalry among males for females to reduce the chance of lethal and destructive conflict.14
There are several problems with this argument. First, why should continuous female sexuality make for more sexual competition in the first place? One might argue the other way around. More availability should make for less competition. When there is only a brief breeding season, competition should be greater. Second, males of many animal species, even some in which females are frequently sexually receptive (such as many of our close primate relatives), do not show much aggression over females. Third, why couldn’t sexual competition, even if it existed, be regulated by cultural rules other than marriage? For instance, society might have adopted a rule whereby men and women circulated among all the opposite-sex members of the group, each person staying a specified length of time with each partner. Such a system presumably would solve the problem of sexual competition. On the other hand, such a system might not work particularly well if individuals came to prefer certain other individuals. Jealousies attending those attachments might give rise to even more competition.