Passeri

Songbird Temporal range: Early Eocene to present
Eastern yellow robin (Eopsaltria australis)
Song of a chipping sparrow (Spizella passerina)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Order:	Passeriformes
Suborder:	Passeri
Families
Many, see text
Synonyms
Oscines

Many, see text

Oscines

A songbird is a bird belonging to the clade Passeri of the perching birds (Passeriformes). Another name that is sometimes seen as a scientific or vernacular name is Oscines, from Latin oscen, "a songbird". This group contains some 4,000 species found all over the world, in which the vocal organ typically is developed in such a way as to produce a diverse and elaborate bird song.

Songbirds form one of the two major lineages of extant perching birds, the other being the Tyranni which are most diverse in the Neotropics and absent from many parts of the world. These have a simpler syrinx musculature, and while their vocalizations are often just as complex and striking as those of songbirds, they are altogether more mechanical sounding. There is a third perching bird lineage, the Acanthisitti from New Zealand, of which only two species remain alive today.

There is evidence to suggest that songbirds evolved 50 million years ago in the part of Gondwana that later became Australia, New Zealand, New Guinea and Antarctica, before spreading around the world.

The song in this clade is essentially territorial in that it communicates the identity and whereabouts of an individual to other birds and also signals sexual intentions. Sexual selection among songbirds is highly based on mimetic vocalization. Female preference has shown in some populations to be based on the extent of a male's song repertoire. The larger a male's repertoire, the more females a male individual attracts. It is not to be confused with bird calls which are used for alarms and contact and are especially important in birds that feed or migrate in flocks. While almost all living birds give calls of some sort, well-developed songs are only given by a few lineages outside the songbirds.

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Wikipedia