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The sunbirds and spiderhunters make up a family, Nectariniidae, of passerine birds. They are small, slender passerines from Old World, with long, usually decurved bill and some species with long tail; many brightly coloured, most with some iridescence, particularly in male. They are living from Africa to Australia, across Madagascar, Egypt, Iran, Yemen, Southern China, Indian subcontinent, Indochinese peninsulas, Philippines, Southeast Asian to nearby Pacific Islands and just reaches northern Australia. The number of species is greater in equatorial and tropical areas. There are 132 species in 15 genera. The family is distributed throughout Africa, the Indian subcontinent, Southeast Asia and just reaches northern Australia. Most sunbirds feed largely on nectar, but also take insects and spiders, especially when feeding young. Flower tubes that bar access to nectar because of their shape, are simply punctured at the base near the nectaries. Fruit is also part of the diet of some species. Their flight is fast and direct on their short wings. The sunbirds have counterparts in two very distantly related groups: the hummingbirds of the Americas and the honeyeaters of Australia. The resemblances are due to convergent evolution brought about by a similar nectar-feeding lifestyle. Some sunbird species can take nectar by hovering like a hummingbird, but they usually perch to feed. ==Description== The family ranges in size from the 5-gram black-bellied sunbird to the spectacled spiderhunter, at about 45 grams. Like the hummingbirds, sunbirds are strongly sexually dimorphic, with the males usually brilliantly plumaged in iridescent colours. In addition to this the tails of many species are longer in the males, and overall the males are larger. Sunbirds have long thin down-curved bills and brush-tipped tubular tongues, both adaptations to their nectar feeding. The spiderhunters, of the genus ''Arachnothera'', are distinct in appearance from the other members of the family. They are typically larger than the other sunbirds, with drab brown plumage that is the same for both sexes, and long, down-curved beaks. In metabolic behaviour similar to that of Andes hummingbirds,〔http://jeb.biologists.org/cgi/content/full/205/16/2325〕 species of sunbirds that live at high altitudes or latitudes will enter torpor while roosting at night, lowering their body temperature and entering a state of low activity and responsiveness.〔 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「sunbird」の詳細全文を読む スポンサード リンク
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