Australo-Papuan babblers | |
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Chestnut-crowned babbler Pomatostomus ruficeps. | |
Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Aves |
Order: | Passeriformes |
Suborder: | Passeri |
Family: |
Pomatostomidae Schodde, 1975 |
Genus: |
Pomatostomus Cabanis, 1850 |
Species | |
The Pomatostomidae (Australo-Papuan or Australasian babblers, also known as pseudo-babblers) are small to medium-sized birds endemic to Australia-New Guinea. For many years, the Australo-Papuan babblers were classified, rather uncertainly, with the Old World babblers (Timaliidae), on the grounds of similar appearance and habits. More recent research, however, indicates that they are too basal to belong the Passerida – let alone the Sylvioidea where the Old World babblers are placed – and they are now classed as a separate family close to the Orthonychidae (logrunners). Five species in one genus are currently recognised, although the red-breasted subspecies rubeculus of the grey-crowned babbler may prove to be a separate species.
The Australo-Papuan babblers are medium-sized terrestrial birds with sombre plumage and long decurved bills. They range in size from 17–27 cm (6.5–10.5 in) in length and 30–85 g (1.1–3.0 oz) in weight. The wings are short and round, and the tail is long and often held fanned which makes it look broad as well. The feet and legs are strong and adapted to a terrestrial existence. There is no sexual dimorphism in the plumage, which is composed of brown, russet and grey colours, with all but the Papuan babbler having striking white markings on the face and throat. The plumage of juvenile birds is similar to that of adults.
All five species are ground-feeding omnivores and highly social. Babblers live in family groups and small flocks of up to about 20 individuals and forage communally, calling loudly to one another all day long. They feed principally on insects and other invertebrates, but will also take seeds, fruits and small vertebrates. Most food is obtained on the ground, although they will also forage in low bushes; the grey-crowned babbler and Papuan babbler feed more extensively in vegetation than the other species. The long bill is used to probe and overturn large objects. They will also hold objects with one foot and hammer them with the bill in order to extract food.