Blyth's Swift
Encyclopedia
The Blyth's Swift is a small bird
, superficially similar to a House Martin
. It is, however, completely unrelated to those passerine
species, since swift
s 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. Blyth's Swifts spend most of their lives in the air, living on the insects they catch in their beaks.
Blyth's Swifts breeds from the outer Himalayas through the Assam
hills. This species is migratory
, and winters in India and Sri Lanka. A 2011 study has many taxonomists splitting this species from the Fork-tailed Swift
complex.
These swifts build their nests on cliffs, laying 2-3 eggs. A swift will return to the same site year after year, rebuilding its nest when necessary.
Blyth's Swifts are similar in size to Common Swift
, and they are black except for a white rump. They can be distinguished from a partially leucistic
Common Swift by the deeper tail fork, longer wings, bigger head and larger white throat patch.
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
, superficially similar to a House Martin
House Martin
The Common House Martin , sometimes called the Northern House Martin or, particularly in Europe, just House Martin, is a migratory passerine bird of the swallow family which breeds in Europe, north Africa and temperate Asia; and winters in sub-Saharan Africa and tropical Asia...
. It is, however, completely unrelated to those passerine
Passerine
A passerine is a bird of the order Passeriformes, which includes more than half of all bird species. Sometimes known as perching birds or, less accurately, as songbirds, the passerines form one of the most diverse terrestrial vertebrate orders: with over 5,000 identified species, it has roughly...
species, since swift
Swift
The swifts are a family, Apodidae, of highly aerial birds. They are superficially similar to swallows, but are actually not closely related to passerine species at all; swifts are in the separate order Apodiformes, which they share with hummingbirds...
s are in the order Apodiformes. The resemblances between the groups are due to convergent evolution
Convergent evolution
Convergent evolution describes the acquisition of the same biological trait in unrelated lineages.The wing is a classic example of convergent evolution in action. Although their last common ancestor did not have wings, both birds and bats do, and are capable of powered flight. The wings are...
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 language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
απους, apous, meaning "without feet". They never settle voluntarily on the ground. Blyth's Swifts spend most of their lives in the air, living on the insects they catch in their beaks.
Blyth's Swifts breeds from the outer Himalayas through the Assam
Assam
Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...
hills. This species is migratory
Bird migration
Bird migration is the regular seasonal journey undertaken by many species of birds. Bird movements include those made in response to changes in food availability, habitat or weather. Sometimes, journeys are not termed "true migration" because they are irregular or in only one direction...
, and winters in India and Sri Lanka. A 2011 study has many taxonomists splitting this species from the Fork-tailed Swift
Fork-tailed Swift
Fork-tailed Swift is the historic name of a kind of bird which has since been divided taxonomically into four species. It could refer to any of four different species of swifts:*Pacific Swift, Apus pacificus*Salim Ali's Swift, Apus salimali...
complex.
These swifts build their nests on cliffs, laying 2-3 eggs. A swift will return to the same site year after year, rebuilding its nest when necessary.
Blyth's Swifts are similar in size to Common Swift
Common Swift
The Common Swift is a small bird, superficially similar to the Barn Swallow or House Martin. It is, however, completely unrelated to those passerine species, since swifts are in the separate order Apodiformes...
, and they are black except for a white rump. They can be distinguished from a partially leucistic
Leucistic
Leucism is a condition characterized by reduced pigmentation in animals and humans. Unlike albinism, it is caused by a reduction in all types of skin pigment, not just melanin.- Details :...
Common Swift by the deeper tail fork, longer wings, bigger head and larger white throat patch.