Bowerbird

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{{Taxobox | color = pink | name = Bowerbirds | image_caption = Male Golden Bowerbird. | regnum = Animalia | phylum = Chordata | classis = Aves | ordo = Passeriformes | familia = Ptilonorhynchidae | familia_authority = GR Gray, 1841 | subdivision_ranks = Genera | subdivision = Many, see text }}

Bowerbirds and catbirds make up the family Ptilonorhynchidae. All are small to medium in size. Although their distribution is centered around the tropical northern part of Australia-New Guinea some species extend into the central Australian desert and the cold mountainous regions of southeast Australia.

Catbirds are so-called because their eerie call resembles that of a domestic cat.

The bowerbirds most notable characteristic is the extraordinarily complex behaviour of males, which is to build a bower to attract mates. This bower is a U-shaped structure of sticks and leaves into which the male places a variety of objects he has collected. These objects--mostly blue or violet in colour--may include hundreds of shells, leaves, flowers, feathers, stones, berries, and even discarded plastic items. The bird will spend hours carefully sorting and arranging his collection, with each thing in a specific place. If an object is moved while the bowerbird is away he will put it back in its place. No two bowers are the same, and the collection of objects reflects the personal taste of each bird. Then at mating time the female will go from bower to bower, carefully inspecting each one. When she finds one to her satisfaction she mates with the owner.

This complex mating behaviour has led some researchers to regard the bowerbirds as the most advanced of any species of bird. It provides also one of the most compelling evidences that the extended phenotype of a species can play a role in sexual selection and indeed act as a powerful mechanism to shape its evolution, as seems to be the case for humans.

Though bowerbirds have traditionally been regarded as closely related to the birds of paradise, recent DNA-DNA hybridisation studies suggest that while both families are part of the great corvid radiation that took place in or near Australia-New Guinea, the bowerbirds are more distant from the birds of paradise than was once thought. Sibley's landmark DNA studies placed them close to the lyrebirds; however, anatomical evidence appears to contradict this and the true relationship remains unclear.

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