Peafowl Temporal range: 3–0 Ma Late Pliocene – Recent |
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Indian peacock displaying. The elongated upper tail coverts make up the train of the Indian peacock. | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Galliformes |
Family: | Phasianidae |
Subfamily: | Phasianinae |
Species | |
Pavo cristatus
Pavo muticus
Afropavo congensis
The peafowl include three species of birds in the genera Pavo and Afropavo of the Phasianidae family, the pheasants and their allies. There are two Asiatic species (the blue or Indian peafowl originally of India and Sri Lanka and the green peafowl of Myanmar, Indochina, and Java) and one African species (the Congo peafowl native only to the Congo Basin). Male peafowl are known for their piercing call and their extravagant plumage. The latter is especially prominent in the Asiatic species, who have an eye-spotted "tail" or "train" of covert feathers which they display as part of a courtship ritual. The term peacock is properly reserved for the male; the female is known as a peahen, and the immature offspring are sometimes called peachicks.
The functions of the elaborate iridescent coloration and large "train" of peacocks have been the subject of extensive scientific debate. Charles Darwin suggested they served to attract females, and the showy features of the males had evolved by sexual selection. More recently, Amotz Zahavi proposed in his handicap theory that these features acted as honest signals of the males' fitness, since less fit males would be disadvantaged by the difficulty of surviving with such large and conspicuous structures.
The Indian peacock has iridescent blue and green plumage. The peacock "tail", known as a "train", consists not of tail quill feathers, but highly elongated upper tail coverts. These feathers are marked with eyespots, best seen when a peacock fans his tail. Both sexes of all species have a crest atop the head. The Indian peahen has a mixture of dull grey, brown, and green in her plumage. The female also displays her plumage to ward off female competition or signal danger to her young.