Dolphins off the coast of Australia have been seen committing rape. It takes 3 males: 2 keep the female from swimming away. If I ever meet a biologist who is familiar with this phenomenon, I have a lot of questions. Many species of dolphins use copulation as a pack-bonding ritual--much like our closest relatives, the chimpanzees. (Bonobos have orgies in which even the young and the elderly participate, and they can go on for hours.) So it's not clear why these males are reduced to rape in order to have intercourse. Maybe they're from a different pod? Female dogs copulate with any male in the vicinity. That way they all think the puppies are theirs, and will protect them.