When you massage someone, the levels of oxytocin go up in the brain, and oxytocin is one of the chemicals that drives attachment.

Women apparently are quite drawn to men who have differences rather than similarities in their histocompatibility system. They pick it up by smell, and they can pick it up from kissing.

There's all kinds of reasons that you fall in love with one person rather than another: Timing is important. Proximity is important. Mystery is important. You fall in love with somebody who's somewhat mysterious, in part because mystery elevates dopamine in the brain, probably pushes you over that threshold to fall in love.

Research shows that couples who have a lot of similarities, including intellectual compatibility, end up staying together.

Good-looking people are always looking for other good-looking people.

Kissing is not just kissing. It is a major escalation or de-escalation point in a powerful process of mate choice.

Haiti is the poorest country in the western hemisphere; some say the poorest in the world.