Why We Are (Mostly) Monogamous

As usual, it’s all about evolution. Researchers with lots of time on their hands (eons, in fact), compared the data of 230 primate species over 75 million years. They found that the threat of baby primates being killed by other males caused monogamy. Scientists have stated that male primates may have become monogamous to protect offspring from rival males. Others disagree, saying monogamy evolved in mammals so that males could guard their mates.

Monogamy is rather rare in the animal kingdom, but there are some who do manage to stay faithful, forever. Apparently, it’s mainly for the kids.

Way back then, babies who were not their own were often considered to be a meal.   Researchers found links between this threat and the development of monogamy. That makes sense: A family (and a species) that stays together, lives longer.

Another study suggests monogamy may have evolved to protect females against competition from other females – which also sort of makes sense. All seem to agree that all this does not necessarily apply for humans, which is certainly a relief. Researchers also determined that male infanticide appeared when primate relationships switched from females mating with multiple males to monogamy; which eventually created the human phenomenon of the single family home and divorce lawyers.

Most ancestral men aspired to polygamy. That is: mating with more than one woman, even if most of them weren’t “evolved” enough to attract more than one. A trait that still exists in some men today.

The problem is that the genetic and psychological urge of human mating was built by, and for, a world in which polygamy was often advantageous, reproductively speaking. That’s why many people and cultures, even in modern societies, often practice polygamy, even while other cultures attempt to abolish it.