There's no rule that regulates how animals obtain the necessary genetic material to reproduce—and as a result, there is a lot of weird animal sex going on out there.

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You may not even realize how much your sense of smell or taste is influencing who you fall in love with.
Move around the board with just a quick spin of the ovaries.
Our reporter checks in with a feng shui consultant to give her dating life a helping hand.
Women and men in ancient cultures used a variety of unusual methods to prevent pregnancy, with differing levels of success (and hygiene).
Turns out this expression of unbridled hedonism isn't so modern after all.
New DNA analysis suggests that interbreeding began 100,000 years ago.
Tropical slipper limpets are pretty unremarkable—until it's mating time. Then things get interesting.
People who view their personality traits as fixed are more affected by romantic rejection, a Stanford study finds.