Biological anthropologist Helen Fisher told us humans evolved romantic love because they needed to pair up to raise their helpless infants. Fisher co-authored an article arguing that romantic love is a drive that humans evolved to aid in reproduction. It’s academic, but quite readable.
Helen Fisher wrote this book chapter in which she describes three human mating systems: lust, romantic love, and attachment love. She argues that love often lasts about four years — about long enough to raise a child together to the point that the child no longer needs constant tending.
She also gave this TED talk about why people pair up romantically.
A lot of evolutionary biologists, like David Buss, agree with Helen Fisher. He explained his ideas on “the roots of love” to PBS.
On the other hand, some love experts question the notion that romantic love’s only function is to help humans raise children. Anthropologist Ted Fischer agrees that joining a couple can give people advantages when it comes to raising kids. “Human babies are so helpless,” Fischer told us.
But, he said, it’s more complicated than that. Joining a romantic twosome is just one strategy for rearing children. “Pair bonding isn’t the only way to do it,” he said.
What’s more, people join couples for reasons other than raising kids. “There’s lots of pair bonding without kids,” Ted Fischer said, “so there are other things going on.”
Here’s a short video that features Ted Fischer talking about why he believes humans couple up.