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parrot, common name for members of the order Psittaciformes, comprising nearly 400 species of colorful birds, pantropical in distribution, including the parakeets. Parrots have large heads and short necks, strong feet with two toes in front and two in back (facilitating climbing and grasping), and strong, thick bills, with the larger hooked upper mandible hinged to the bones of the head. They are arboreal, typically feeding (depending on the species) on seeds, fruits, nectar, pollen, and arthropods, but a few species, such as the kea (Nestor notabilis) of New Zealand, will prey on birds and animals. Parrots are notable for their intelligence, with a number of species known to have toolmaking, puzzle-solving, or number skills. They feed their young by regurgitation, and they have swellings (ceres) at the base of the nostrils.
Usually their voices are harsh, but the thick, fleshy tongue and special voice apparatus permit a wide range of articulations, and some species can be taught to imitate the human voice. The best mimics are the African gray parrots, Psittacus erithacus, and the Amazons, genus Amazona. In size parrots range from the 31-2-in. (8.7-cm) pygmy parrot of the South Pacific to the 40-in. (100-cm) hyacinth macaw (Anodorhynchus hyacinthinus) of South America, while in build they vary from the stocky lovebirds, e.g., the yellow-collared, or masked, lovebird (Agapornis personata), to the slender lories, e.g., the purple-naped lory (Lorius domicella) and the cockatoo. The flightless kakapo (Strigops habroptilus) of New Zealand is the heaviest, weighing up to 9 lb (4 kg), and one of the longest lived, with a lifespan of up to 120 years. The plumage is typically brilliant, the bodies solid green, yellow, red, white, or black with contrasting red, yellow, or blue on the head, wings, and tail.
The cockatoos, crested parrots native to the Australian region, may be pink, white with yellow or scarlet crests, or dark-plumaged, like the great black, or palm, cockatoo, Probosciger aterrimus. They eat insects and are also able to crack extremely hard nuts. The smaller cockatiels are gray with yellow heads. The large, long-tailed macaws are found in the rain forests of Central and South America. The species are named for their gaudy colors, e.g., the scarlet (Ara macao), blue-and-yellow (A. ararauna), and red-and-green, or green-winged, macaws (A. chloropterus). In captivity adult macaws may be vicious. In the wild they travel in pairs. The small Old World parrots known as lovebirds are so named for the apparent fondness of the mates for one another. The Australasian lories and the smaller lorikeets feed on fruits and nectar.
Parrots are popular as cage birds, but they require intellectual stimulation, and many species can become aggressive as they mature if improperly raised. Care also should be exercised by selecting birds with known histories, since even apparently healthy birds may be carriers of infectious psittacosis, or parrot fever. Captive parrots that have been released or escaped have become established and even invasive in some areas, such as the monk parakeet in New York City, peach-faced lovebirds in Arizona, and a number of species in S California.
Parrots are classified in the phylum Chordata, subphylum Vertebrata, class Aves, order Psittaciformes, superfamilies Psittacoidea, Cacatuoidea, and Strigopoidea.
See study by J. M. Corshaw (1973).
a bird of the subfamily Kakatoeinae of the family Psittacidae. The body measures 60– cm long. A characteristic feature is the crest on the head. Cockatoos are found from the islands of Kalimantan and Flores, the Philippines, and New Guinea to the Solomon Islands, Australia, and Tasmania. There are five genera: Probosciger, Calyptorhynchus, Callocephalon, Kakatoe, and Nymphicus. These genera comprise 17 species. The birds live in forests, often near fields, and stay in flocks. They eat fruits and seeds, and their powerful beaks are capable of cracking even the very hard fruits of palm trees. In some places cockatoos seriously damage crops. They build their nest in tree hollows or in fissures of cliffs. The large cockatoos lay two or three white
|Table 1. Composition of coal tar|
|Fraction||Output (% of tar bulk)||Boiling point (°C)||Density at 20°C (kg per cu m)||Recoverable substances|
|Light…………||0.2–0.8||To 170||900–960||Benzene and its homologues|
|Phenol…………||1.7–2.0||170–210||1,000–1,010, 010||Phenols, pyridine bases|
|Heavy (absorbring)….||8.0–10.0||230–270||1,050–1,070||Methyl naphthalenes, acenaphthene|
|Anthracene……||20.0–25.0||270–360(and to 400)||1,080–1,130||Anthracene, phenanthrene, carbazole, others|
|Pitch………||50.0–65.0||Over 360||1,200–1,300||Pyrene and other highly condensed aromatic compounds|
eggs; the small birds of the genus Nymphicus lay five or six eggs.Cockatoos are often kept in cages.