Sittellas | |
---|---|
Varied sittella, Daphoenositta chrysoptera | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Passeriformes |
Suborder: | Passeri |
Family: |
Neosittidae Ridgway, 1904 |
Genus: |
Daphoenositta De Vis, 1897 |
Species | |
|
|
Global range (In red) |
The sittellas are a family, Neosittidae, of small passerine birds found only in Australasia. They resemble nuthatches, but whilst they were considered to be in that family for many years they are now afforded their own family. They do not migrate other than for local movements.
The sittellas are small woodland birds with thin pointed down-curved bills, which they use to extricate insects from bark. Nests are open cups in forked branches.
They were formerly classified in two separate genera with the black sittella in Daphoenositta and the varied and Papuan sittellas in Neositta. The two genera are now usually merged with Daphoenositta having priority.
The true evolutionary affinities of the sittellas have long been clouded by their close resemblance to the Northern Hemisphere nuthatches. As late as 1967 the sittellas were retained in that family by some authorities, although doubts about that placement had been voiced in the previous decades. Both their climbing technique and overall morphology are extremely similar; however they differ both in their sociality and their nesting behaviour, as sittellas create nests on branches whereas nuthatches nest in cavities in trees. In addition the specifics of the morphology of the leg differed, with sittellas having leg muscles more similar to those of the honeyeaters. Their placement was then moved to various families, including the Old World babblers (an infamous wastebin taxon), the true treecreepers (Certhiidae, which range across the Holarctic and Africa) and the Australian treecreepers (Climacteridae). Their relationship with the Australian radiation of passerines was suggested by S.A. Parker on the basis of egg colour, nest structure and nestling plumage, and their position in this radiation was vindicated by Sibley and Ahlquist's DNA–DNA hybridization studies. These researchers placed the sittellas in a monotypic tribe within the superfamily Corvidae. Today they are afforded their own family in a clade close to the berrypeckers and longbills (Melanocharitidae) and the whistlers (Pachycephalidae).