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The Alpine swift (''Tachymarptis melba'') or ''Apus melba'', is a species of swift. Alpine swifts breed in mountains from southern Europe to the Himalaya. Like common swifts, they are strongly migratory, and winter much further south in southern Africa. Alpine Swift happens to be the fastest of the Swift family. Swifts have very short legs which are used for clinging to vertical surfaces. They never settle voluntarily on the ground, spending most of their lives in the air living on the insects they catch in their beaks. Alpine swift are able to stay aloft in the air for up to seven months at a time, even drinking water "on the wing". Their vital physiological processes, including sleep, can be performed while in continuous flight. == Description and biology == The bird is superficially similar to a large barn swallow or house martin. It is, however, completely unrelated to those passerine species, since swifts are in the order Apodiformes. The resemblances between the groups are due to convergent evolution, reflecting similar life styles. Swifts have very short legs which they use only for clinging to vertical surfaces. The scientific name comes from the Ancient Greek ''απους, apous'', meaning "without feet". They never settle voluntarily on the ground. Alpine swifts breed in mountains from southern Europe to the Himalaya. Like common swifts, they are strongly migratory, and winter much further south in southern Africa. They wander widely on migration, and are regularly seen in much of southern Europe and Asia. The species seems to have been much more widespread during the last ice age, with a large colony breeding, for example in the Late Pleistocene Cave No 16, Bulgaria, around 18,000–40,000 years ago.〔Boev, Z. 1998. A range fluctuation of Alpine swift (''Apus melba'' (L., 1758)) (Apodidae - Aves) in Northern Balkan Peninsula in the Riss-Wurm interglacial. - Biogeographia, Nuova Serie, Siena, Vol. 19, 1997: pp. 213–218.〕 The same situation has been found for Komarowa Cave near Częstochowa, Poland during a period about 20,000–40,000 years ago.〔Tomek, Teresa & Bocheński, Zygmunt (2005): "(Weichselian and Holocene bird remains from Komarowa Cave, Central Poland )". ''Acta zoologica cracoviensia'', Vol. 48A, (1-2): pp. 43–65.〕 These apodiformes build their nests in colonies in a suitable cliff hole or cave, laying 2–3 eggs. Swifts will return to the same sites year after year, rebuilding their nests when necessary, and pairing for life. Young swifts in the nest can drop their body temperature and become torpid if bad weather prevents their parents from catching insects nearby. They have adapted well to urban conditions, frequently nesting in old buildings in towns around the Mediterranean, where large, low-flying flocks are a familiar feature in summer. Alpine swifts are readily distinguished from the common swifts by their larger size and their white belly and throat. They are around twice as big as most other swifts in its range, about in length, with a wingspan of and a weight of around .〔(BTO Birdfacts - Alpine swift ), British Trust for Ornithology, BTO.org website.〕 They're largely dark brown in colour, with white patches underneath the beak and on the breast that are separated by a dark brown streak. Juveniles are similar to adults, but their feathers are pale edged.〔Stevenson & Fanshawe. ''Field Guide to the Birds of East Africa: Kenya, Tanzania, Uganda, Rwanda, Burundi'', Elsevier Science, 2001, ISBN 978-0856610790.〕 In comparison, the common swift has a wingspan of around . A dark neck band separates the white throat from the white belly. They have a short forked tail and very long swept-back wings that resemble a crescent or a boomerang but may (as in the image) be held stretched straight out. Their flight is slower and more powerful than that of their smaller relative, with a call that is a drawn-out twittering (listen at right). 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「alpine swift」の詳細全文を読む スポンサード リンク
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