Romantic love allows you to focus mating energy. Attachment sustains that relationship as long as necessary to raise your baby.

Romantic love is an obsession. It possesses you. You lose your sense of self. You can’t stop thinking about another human being.

If two very different people pool their DNA, they'll create more genetic variety, and their young will come to the job of parenting with a wider array of skills.

Until recently, we regarded love as supernatural. We were willing to study the brain chemistry of fear and depression and anger but not love.

You've got to remember that men are men and women are women. And although a lot of similarities, there are some real differences.

We're not very dangerous animals; we don't have a horn like a rhino or quills like a porcupine.

Real competition can drive up testosterone, which boosts libido.