Also on islands in Geelvink Bay, the Aru Islands, and the West Papuan Islands. Native Range: Coastal and inner lowland areas of New Guinea to an altitude of some 1,300 m. Probosciger aterrimus stenolopbus (Van Oort) Prohosciger aterrimus aterrimus (Gmelin)ģ. Three subspecies are now generally recognized:ġ. Synonyms: Great Palm Cockatoo, Great Black Cockatoo, Cape York Cockatoo, Black Macaw, Goliath Cockatoo, Aratoo. The Palm Cockatoo Probosciger aterrimus (Gmelin) The elongated feathers give the crest of the Palm Cockatoo a distinctive, plume-like quality unique among the cockatoos. It consists of numerous backward-curving, narrow feathers which separate when the crest is raised. The crest is also quite distinct from that of other cockatoo genera. Holyoak 0972) concluded that, without these specialized steps, the bird would have great difficulty in dealing with small seeds. The tip of the beak, and the outermost step are used for tearing open large fruits. The inner step is used to deal with food items such as small seeds, while the middle step deals with the larger items. The makeup of the upper mandible is interesting in that there are two projecting areas of flat horny tissue (rampotheca), which forms three steps. The sharply pointed tip of the upper mandible extends well below the lower mandible, making it the largest beak of any psittacine in relation to its body size (only in the Hyacinthine Macaw, Anodorhynchus hyacinthinus, a larger bird, is the beak consistently more massive). The specialized beak is unique among the cockatoos both for its size and its apparent function. It is obviously a very isolated form, however it is viewed, and worthy of extended investigation." (Mathews, 1916). Wrote that "The osteology differs so much from that of other cockatoos that I have separated the present species as of family rank, and it is possible that a closer examination would cause it to be placed nearer the Macaws than the Cockatoos. On comparing the hone structures of Probosciger and other cockatoos species, the great Australian ornithologist, Gregory M. Even Kuhl, who named the genus, was compelled to write "Species intermedia inter Ara et Kakadoes" (species intermediate between macaws and cockatoos). Probosciger to other cockatoo species and the size of its beak led early researchers to compare them with macaws. Conversely, in Calyptorbyncbus, colorful and dominant hands are located on the tail, and there is quite marked plumage dimorphism of the sexes in most of the six species. Apart from the hare red cheek patches which do not occur in any of the black cockatoos, the plumage of Probosciger is almost totally and uniformly black in both sexes. Ly be ascertained by comparing the size of the birds, examining the beak, and checking the colors and patterns of the plumage. The superficiality of any resemblance can quick. Studies have revealed, however, that Probosciger has distinctive anatomical peculiarities which clearly separate it from the black cockatoos. Excitement or alarm causes the patch to visibly deepen in color, a process known as "blushing."ĭue to its blackish color Probosciger was formerly loosely classified along with the black cockatoos of the genus Calyptorbyncbus. Another unique feature is the ahility of the hire! toĬhange the color of its naked cheek patches from red to pink and vice versa, depending on its mood. A peculiarity of the beak is that the upper and lower mandibles do not close completely together, leaving the black-tipped, red tongue clearly visible. The main diagnostic features of the genus include the huge, sharply pointed, upper mandible, the bare, red cheek-patches, and the naked inner thighs. T his monotypic genus contains the largest and probably the most spectacular of the cockatoos.
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