Monogamy

There are two schools of thought on the origin of monogamy. The idea that monogamy provides two parents rather than just one for rearing offspring was considered a side benefit of monogamy rather than a cause and was quickly thrown out. Only a few species of mammals are socially monogamous, only 25% among primates.

One school of thought is that monogamy came about as a means to prevent infanticide among primates. Fathers defended their young against being killed by other males. In the primate world infants are breastfed for greater lengths of time, sometimes years and competing males don’t approve and thus tend to kill the infant to gain the attentions of the female unless there is a father around to protect them.

The other school of thought considers that a greater physical distance between females made it less profitable sex-wise for males to roam. In this case solitary females came before social monogamy. The females spread out to monopolize better food sources that were harder to find. Distances between the females made it too difficult for the male to defend more than one female so the male stuck around and hence a monogamous relationship occurred.

Only primates, excluding humans were considered in this study because some people are monogamous and others are not.