Salim Ali's swift (''Apus salimalii'') is a small

bird Birds are a group of warm-blooded vertebrates constituting the class Aves (), characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a strong yet lightweig ...

, superficially similar to a

house martin ''Delichon'' is a small genus of passerine birds that belongs to the swallow family and contains four species called house martins. These are chunky, bull-headed and short-tailed birds, blackish-blue above with a contrasting white rump, and w ...

. It is, however, completely unrelated to those

passerine A passerine () is any bird of the order Passeriformes (; from Latin 'sparrow' and '-shaped'), which includes more than half of all bird species. Sometimes known as perching birds, passerines are distinguished from other orders of birds by th ...

species, since

swift Swift or SWIFT most commonly refers to: * SWIFT, an international organization facilitating transactions between banks ** SWIFT code * Swift (programming language) * Swift (bird), a family of birds It may also refer to: Organizations * SWIFT, ...

s are in the order Apodiformes. The resemblances between the groups are due to

convergent evolution Convergent evolution is the independent evolution of similar features in species of different periods or epochs in time. Convergent evolution creates analogous structures that have similar form or function but were not present in the last com ...

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 Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

απους, ''apous'', meaning "without feet". They never settle voluntarily on the ground. Salim Ali's swifts spend most of their lives in the air, living on the insects they catch in their beaks. Salim Ali's swifts breed from the eastern

Tibetan Plateau The Tibetan Plateau (, also known as the Qinghai–Tibet Plateau or the Qing–Zang Plateau () or as the Himalayan Plateau in India, is a vast elevated plateau located at the intersection of Central, South and East Asia covering most of the ...

eastwards through western

Sichuan Sichuan (; zh, c=, labels=no, ; zh, p=Sìchuān; alternatively romanized as Szechuan or Szechwan; formerly also referred to as "West China" or "Western China" by Protestant missions) is a province in Southwest China occupying most of the ...

province. This species is migratory; however, its wintering range is unknown. This swift is longer tailed and has a narrower white rump compared to other species in the complex. A 2011 study has many taxonomists splitting this species from the fork-tailed swift complex. These swifts build their nests on cliffs, laying 2 or 3 eggs. A swift will return to the same site year after year, rebuilding its nest when necessary. Salim Ali's swifts are similar in size to

common swift The common swift (''Apus apus'') is a medium-sized bird, superficially similar to the barn swallow or house martin but somewhat larger, though not stemming from those passerine species, being in the order Apodiformes. The resemblances between t ...

, and they are black except for a white rump. They can be distinguished from a partially

leucistic Leucism () is a wide variety of conditions that result in the partial loss of pigmentation in an animal—causing white, pale, or patchy coloration of the skin, hair, feathers, scales, or cuticles, but not the eyes. It is occasionally spelled ...

common swift by the deeper tail fork, longer wings, bigger head and larger white throat patch. It was previously mis-categorized as an alternative name for '' Apus pacificus kanoi''.

References

{{Taxonbar, from=Q1276542 Salim Ali's swift Memorials to Salim Ali Birds of Tibet Salim Ali's swift