Hair that looks like it's been naturally sun-bleached makes you seem youthful, like you spend a lot of time outdoors. And that appeals to most people.

Men have a psychological need to show off their courage and strength. When he sees you talking to another guy, that instinct kicks in and he jumps to protect you and prove he's worthy of your love.

The main characteristics of romantic love are craving: an intense craving to be with a particular person, not just sexually, but emotionally.

There is more and more data indicating that there is a biological basis to your political views.

A Rolex watch or an expensive car are the things guys often use to show status, wealth, and basic desirability.

Real competition can drive up testosterone, which boosts libido.

You can really get poked in the back and not feel it very much, but just a feather around your lips and you really do feel it.