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The turacos make up the bird family Musophagidae (literally "banana-eaters"), which includes plantain-eaters and go-away-birds. In southern Africa both turacos and go-away-birds are commonly known as louries. They are semi-zygodactylous – the fourth (outer) toe can be switched back and forth. The second and third toes, which always point forward, are conjoined in some species. Musophagids often have prominent crests and long tails; the turacos are noted for peculiar and unique pigments giving them their bright green and red feathers. Traditionally, this group has been allied with the cuckoos in the order Cuculiformes, but the Sibley-Ahlquist taxonomy raises this group to a full order Musophagiformes. They have been proposed to link the hoatzin to the other living birds,〔Hughes & Baker (1999)〕 but this was later disputed.〔Sorenson ''et al.'' (2003)〕 Recent genetic analysis have strongly supported the order ranking of Musophagiformes.〔Ericson, P.G.P. ''et al.'' (2006) (Diversification of Neoaves: integration of molecular sequence data and fossils ). Biology Letters, 2(4):543–547〕 Musophagids are medium-sized arboreal birds endemic to sub-Saharan Africa, where they live in forests, woodland and savanna. Their flight is weak, but they run quickly through the tree canopy. They feed mostly on fruits and to a lesser extent on leaves, buds, and flowers, occasionally taking small insects, snails, and slugs. As their name suggests, turacos enjoy bananas and can become so tame as to be hand-fed. They are also partial to grapes and pawpaw (papaya). They are gregarious birds that do not migrate but move in family groups of up to 10. Many species are noisy, with the go-away-birds being especially noted for their piercing alarm calls, which alert other fauna to the presence of predators or hunters; their common name refers to this. Musophagids build large stick nests in trees, and lay 2 or 3 eggs. The young are born with thick down and open, or nearly-open, eyes. ==Morphology== Most turacos are medium-sized birds – an exception being the large great blue turaco – with long tails and short, rounded wings. They range in length from . Their flight is weak, but they are strong climbers and are able to move nimbly on branches and through vegetation. They have a unique foot arrangement, where the fourth toe can be brought around to the back of the foot where it almost touches the first toe, or brought around so that it is near the second and third. In spite of this flexibility the toe is actually usually held at right angles to the axis of the foot. The plumage of go-away-birds and plantain-eaters is mainly grey and white. The turacos on the other hand are brightly coloured birds, usually blue, green or purple. The green colour in turacos comes from turacoverdin, the only true green pigment in birds known to date. Other "greens" in bird colors result from a yellow pigment such as some carotenoid, combined with the prismatic physical structure of the feather itself which scatters the light in a particular way and giving a blue colour. Turaco wings contain the red pigment turacin, unlike in other birds where red colour is due to carotenoids. Both pigments are derived from porphyrins and only known from the Musophagidae at present, but especially the little-researched turacoverdin might have relatives in other birds. The incidence of turacoverdin in relation to habitat is of interest to scientists, being present in forest species but absent in savanna and acacia living species.〔 Little is known about the longevity of wild turacos, but in captivity they are proving to be exceptionally long-lived, easily living to 30 in captivity. A bird in the Cotswold Wildlife Park collection approached its 37th year.〔Originally from Nigel Hewston, discussed at the ITS AGM in spring 2012 (at the same venue)〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Turaco」の詳細全文を読む スポンサード リンク
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