Only 3-5% of about 5,000 mammalian species, humans included, are known to form monogamous bonds. But why is this, and what are the benefits?
Now, there’s a key difference between human monogamy and, say, french angelfish or bald eagles (amongst others) who mate for life, whereas humans may date multiple people, break up with them, marry and divorce, cheat, etc. “Monogamy”, Greek for “one unity”, is the “practice of marriage or sexual partnering with one spouse”, according to the New World Encyclopedia. Personally, I consider myself monogamous. But there are a variety of cultures that do allow polygamy, which is often dictated by one’s religion.
But here’s the kicker: we aren’t naturally monogamous. And we still aren’t.
Our close ancestor, the Neanderthal, was even a bit promiscuous (source). The reason for monogamy is still highly disputed amongst anthropologists. Meanwhile, our living relative the orangutan competes for access to as many females as possible. Some studies show that monogamous trends may have begun due to an increase in STDs, while others claim monogamous bonds help offspring, and others bring to light the simple fact that sperm is a pretty common thing, and therefore males have the natural desire to spread their DNA to as many hosts as possible. Yet, homo sapiens have more paternal investment in offspring than any other mammal.
So, then, we have consciously chosen to be monogamous. We weren’t “supposed to” evolve into either monogamous or polygamous creatures. Of course, our culture has evolved to suit a monogamous lifestyle; we live with a significant other, create a lifestyle with them, and presumably remain with them until death.
We practice monogamy for order and investment–not necessarily because it’s natural.
In that sense, there are two types of monogamy that make up our society:
- Sexual monogamy: a pair that mates with only each other
- Social monogamy: a pair that shares a 1:1 relationship based on social norms (ex. living together)
About 5% of Americans are polygamous (here is a list of areas of the world that practice polygamy), and are seen as a social taboo, as they stick out from the common practices of the society around them. But I think the fact that we as a species have the ability to choose between polygamy and monogamy stands as a testament to our complexity of a species as a whole.
“Like the other 97% of species, humans are not monogamous by nature. We just pretend that we are.”-Oliver Markus