(noun) A perching bird in the formal scientific order Passeriformes. This is the largest order of birds and includes more than half the world's different bird species, with more than 5,000 species classified as passerines. Often inaccurately called songbirds, these birds do share many characteristics, but not all birds that could be called songbirds are technically passerines.
The typical characteristics shared by most passerine birds include:
- Small to medium body size
- Relatively vocal, including different calls and often elaborate songs
- Altricial chicks that need extensive parent care after hatching
- Relatively bright colors or distinct markings
- Unwebbed toes and feet
The most prominent characteristic of passerine birds, however, is the anisodactyl arrangement of toes. These birds have four toes, three facing forward and one backward, which allows the bird to easily cling to both horizontal and nearly vertical perches, including branches and tree trunks. These birds also have an adaptation in their legs that gives them extra strength for perching, and in fact, the relaxed position of their feet and talons is to be clenched securely, so the birds are able to perch easily even when sleeping.
With more than half the world's birds being classified as passerines, these birds are familiar to all birders, and include species such as warblers, thrushes, sparrows, finches, jays, larks, tits and wrens.
Photo – Scarlet Tanager © Ed Schneider
PASS-err-eyen or PASS-err-eeen
Passeriform Bird, Passerine Bird