Any kind of novelty or excitement drives up dopamine in the brain, and dopamine is associated with romantic love.

A world without love is a deadly place.

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

Your sweetheart calls you by another's name. His eyes linger too long on your best friend. He talks with excitement about a girl at work. And the fire catches. Jealousy - that sickening combination of possessiveness, suspicion, rage, and humiliation - can overtake your mind and threaten your very core as you contemplate your rival.

It's almost as if men who get tribal tattoos are trying to signal that they are dangerous, they're to be respected, and they're powerful.

As women in industrial societies join the paid workforce, they gain the economic means to depart unhappy marriages more easily.

Real competition can drive up testosterone, which boosts libido.