A large number of birds inhabit the tropical forest regions of the world. The most remarkable from the point of view of social behavior is the giant pitta. The male pitta, unusually for a bird, is about three times the size of the female and each year takes a harem of three or four females. Each female builds a separate nest in the same vicinity and relies on the male to provide her with food during the breeding season. The male also provides protection from predators as well as defending the harem against rivals.