From an evolutionary and biological perspective, animals are driven to have sex in order to procreate. But there is a lot more to sexual relations between animals. Animal sex is at least as strange and varied as human sex. A male might copulate with many females. And female animals of many species can be choosy, too. Homosexuality is common. Monogamy is rare. And the animal kingdom is full of swingers. In short, with animals, sex can be wild.
A Twitter hashtag, #JunkOff, illustrates the steamier side of biology — and its importance to understanding evolution.
With the bill and webbed toes of a duck, tail of a beaver and body of an otter, platypuses are some of the strangest-looking animals on the planet. Their mating behaviors are just as odd, involving venom battles, tail biting and aquatic dances.
The swollen red bottom of a female balloon may not be the signal of sexual fitness that researchers thought it was.