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.

If we remained perpetually infatuated, we couldn't eat, sleep or work.

Romantic love is an addiction: a perfectly wonderful addiction when it's going well, and a perfectly horrible addiction when it's going poorly.

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

In general, men are wired to notice obvious signs that convey interest in mating - a warm smile, for example - and ignore other subtleties, like if your lipstick is faded.

Both sexes like the exercise and challenge of sports, but for men it's also a basic display behavior for impressing and winning a mate.

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