Bowerbirds are the bird family Ptilonorhynchidae. The family has 20 species in eight genera. Bowerbirds are most known for their unique courtship behaviour. Males build a structure and decorate it with sticks and brightly coloured objects. The Vogelkop bowerbird is a good example. The function of this courtship ritual is to attract a mate. The bowerbirds have a "female choice" mating system.