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Alpine Swift The Alpine Swift (Apus melba) is a small bird, 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. These birds have very short legs which they use only for clinging to vertical surfaces. The scientific name comes from the 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 Europe and Asia. Alpine Swifts build their nests in colonies in a suitable cliff hole or cave, laying 2-3 eggs. A swift will return to the same site year after year, rebuilding its nest when necessary. These birds pair 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. Alpine Swifts spend most of their lives in the air, living on the insects they catch in their beaks. They drink on the wing, but roost on vertical cliffs or walls. Alpine Swifts are readily identified by their large size. Their wingspan is 55cm compared to the 42cm of Common Swift. They are black except for a white belly and throat, with a dark neck band separating the white areas. They have a short forked tail and very long swept-back wings that resemble a crescent or a boomerang. The flight is slower and more powerful than that of their smaller relative. The call is a drawn-out twittering. See also: Taxonomy This species, and the related African species Mottled Swift, are sometimes separated into the genus Tachymarptis, but genetic evidence suggests that this would leave the remainder of Apus as polyphyletic. In the Sibley-Ahlquist taxonomy, the old order Apodiformes is split. Swifts remain in that order, but hummingbirds are put into a new order, Trochiliformes.
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