Parrot
2007 Schools Wikipedia Selection. Related subjects: Birds
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Scarlet Macaw Ara macao
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Cacatuidae |
Parrots or Psittacines ( pronounced /ˈsɪtəˌsaɪnz/ , ; order Psittaciformes) includes about 353 species of bird which are generally grouped into two families: the Cacatuidae (also called cockatoos), and the Psittacidae (also called true parrots).
All members of the order have a characteristic curved beak shape with the upper mandible having slight mobility in the joint with the skull and a generally erect stance. All parrots are zygodactyl, having the four toes on each foot placed two at the front and two back.
Parrots can be found in most of the warm parts of the world, including India, southeast Asia and west Africa, with one species – now extinct – in the United States (the Carolina Parakeet). By far the greatest number of parrot species, however, come from Australasia, South America and Central America.
Evolution and systematics
Origins
In general, an area which has, relative to other areas, a great concentration of different species within a particular family is likely to be the original ancestral home of that family. The diversity of Psittaciformes in South America and Australasia suggests that the order has a Gondwanian origin. The parrot family's fossil record, however, is sparse and their origin remains a matter of informed speculation rather than fact.
The earliest known record of parrot-like birds dates to the late Cretaceous about 70 million years ago. A single 15 mm fragment from a lower bill found in Wyoming is similar to that of a modern lorikeet. It is not clear if this find should be classified as a parrot or not.
Europe is the site of more extensive records from the Eocene (58 to 36 million years ago). Several fairly complete skeletons of parrot-like birds have been found in England and Germany. Some uncertainty remains, but on the whole it seems more likely that these are not true ancestors of the modern parrots, but are a related group which evolved in the Northern Hemisphere but have since died out.
The Southern Hemisphere does not have nearly as rich a fossil record for the period of interest as the Northern, and contains no known parrot-like remains earlier than the early to middle Miocene, around 20 million years ago. At this point, however, is found the first unambiguous parrot fossil (as opposed to a parrot-like one), an upper jaw which is indistinguishable from that of a modern white cockatoo .
Phylogeny
The phylogeny of the parrots is still under investigation, and no definite answers are available for entire sections. The classifications as presented reflects the current status, and are subject to change when new studies resolve some of the open questions. For that reason, this classification should be treated as preliminary.
It is unquestionable that the Psittaciformes consist of 2 major lineages of family rank: the true parrots (Psittacidae) and the cockatoos (Cacatuidae). The Cacatuidae are quite distinct, having a movable headcrest, different arrangement of the carotid arteries, a gall bladder, differences in the skull bones, and lack the Dyck texture feathers which, in the Psittacidae, scatters light in such a way as to produce the vibrant colours of so many parrots.
While understanding of the relationships between subgroups of true parrots - e.g. the one containing the Grey Parrot vs. the relatives of the budgerigar - are rather well resolved and knowledge of relationships between species has much improved in the last years, it is still a matter of dispute whether the distinct lineages of true parrots should be considered subfamilies or tribes. Due to parrot fossils and molecular divergence date estimates providing insufficient data to properly resolve when exactly the major diversification and divergence periods in parrot evolution took place, i.e., how distinct the various lineages are really from each other, or how fast and radically they were changed by evolution.
The matter hinges much upon the status of the lorikeets, which a number of authorities regard as a third family Loriidae rather than part of the Psittacidae (e.g. Forshaw & Cooper, 1989). Others lump all Psittaciformes into one giant family. The majority view, however, is that they are distinct enough to warrant subfamily status, but some consider the quite pronounced differences not evidence of a uniquely deep evolutionary split but rather not different quantitatively from the differences between neotropical and Australian parakeets, for example. Biogeography, however, suggests that the lorikeets are best considered a uniquely distinct lineage, not as divergent as cockatoos, but still standing apart from the remaining psittacines.
Systematics
- A list of all parrots by common name in alphabetical order.
- Taxonomic list of Cacatuidae species, some 20 species in 6 genera
- This list provides the taxonomic sequence of Psittacidae genera and species following a two-subfamily approach, with the distinct radiations of true parrots considered tribes,
- Below is a version of the latter in which more subfamilies are recognized. Molecular data suggests that several subfamilies might indeed be valid, but arrangement of tribes in these is different.
Family Psittacidae: true parrots, over 300 species
- Subfamily Loriinae: 12 genera with 53 species of lorikeets and lories, centered in New Guinea, spreading to Australia, Indonesia, and the islands of the south Pacific.
- Subfamily Nestorinae: 3 species in 1 genus, the Kea and Kākā of New Zealand and the extinct Norfolk Island Kaka
- Subfamily Strigopinae: Kakapo
- Subfamily Micropsittinae: 6 species of pygmy parrot, all in a single genus
- Subfamily Psittacinae
- Tribe Psittacini: Afrotropical parrots, 12 species in 3 genera
- Tribe Psittrichadini: Pesquet's Parrot
- Tribe Cyclopsittacini: fig parrots, 6 species in 3 genera, all from New Guinea or nearby
- Tribe Polytelini: three genera.
- Tribe Psittaculini: Paleotropic psittaculine parrots, 66 species in 12 genera, distributed from India to Australasia
- Subfamily Platycercinae: 28 species in 11 genera.
- Tribe Platycercini: 18 species in 8 genera, including the rosellas.
- Tribe Melopsittacini: one genus with one species, the Budgerigar.
- Tribe Neophemini: two small genera of parrots.
- Tribe Pezoporini: one genus of parrots with two species.
- Subfamily Arinae: Neotropical parrots, 148 species in 30 genera
Parrots and humans
Parrots as vulnerable or endangered species
The Convention on the International Trade in Endangered Species ( CITES) has made the sale of all wild caught parrot species illegal; the highly endangered species are on on the CITES appendix 1 list and all of the other parrot species are on the CITES appendix 2 list of vunerable species.
Parrots as pets
Parrots are kept as pets, particularly conures, macaws, Amazons, cockatoos, African Greys, lovebirds, Cockatiels, Budgerigars and parakeets, because of their rich and varied colouration. Sometimes the wings of such birds are clipped, but many people keep flighted pet parrots. Some parrot species, including cockatoos, Amazon parrots, African Grey Parrots and the larger macaws, have very long life-spans of up to 80 years.
In 2004, Britain's Daily Mirror newspaper carried the story of a female macaw supposedly born in 1899, and subsequently a pet of Winston Churchill during the World War; the aged parrot, called Charlie, was reputed to curse the Nazis and Adolf Hitler . Subsequent research strongly suggested that the parrot had never belonged to Winston Churchill, although Charlie's great age was not in question.
The popularity of parrots as pets has led to a thriving - and often illegal - trade in the birds, and some species are now threatened with extinction. The scale of the problem can be appreciated in the Tony Silva case of 1996, in which a world-renowned parrot expert and former director at Tenerife's Loro Parque (Europe's largest parrot park) was jailed in the US for 82 months and fined $100,000 for smuggling Hyacinth Macaws 1. The case rocked conservationist and ornithological circles, leading to calls for greater protection and control over trade in the birds. Loro Parque has since become well known for parrot conservation work.
In some wildlife centers, larger parrot species such as macaws are used in bird displays.
Sound imitation and speech
Many species can imitate human speech or other sounds, and the results of a study by Irene Pepperberg suggest a high learning ability in an African Grey Parrot named Alex. Alex has been trained to use words to identify objects, describe them, count them, and even answer complex questions such as "How many red squares?" with over 80% accuracy. Other scholars claim that parrots are only repeating words with no idea of their meanings and point to Pepperberg's results as being nothing but an expression of classical conditioning, or possibly a manifestation of the Clever Hans effect.
Feral populations
Escaped parrots of several species have proved surprisingly hardy in adapting to conditions in Europe and North America. They sometimes even multiply to the point of becoming a nuisance, or a minor pest and a threat to local ecosystems; this is now occurring in Spain, in Barcelona and Tenerife.
A sizeable population of naturalized Rose-ringed Parakeets (Psittacula krameri) exists in and around cities in England, the Netherlands, Belgium and western and southern Germany. They are believed (and in some cases documented) to have descended from escaped or released pets. The largest UK roost of these is thought to be in Esher, Surrey, numbering several thousand.
Often flocking with the naturalized P. krameri populations in Belgium and England are smaller populations of Alexandrine Parakeets (Psittacula eupatria).
There are also populations of the Monk Parakeet (Myiopsitta monachus) which have established themselves in many areas of the United States and Spain.
In the United Stares are furthermore found feral some Rose-ringed Parakeets, some Brotogeris ssp. (mainly B. versicolurus ( Canary-winged Parakeet a.k.a. White-winged Parrot) and/or B. chiriri ( Yellow-chevroned Parakeet/Parrot) in a few areas. A population of naturalized Rose-collared aka Peach-faced Lovebirds (Agapornis roseicollis) have naturalized themselves in Tucson, Arizona.
Several species, including Red-lored Parrots (Amazona autumnalis), Lilac-crowned Parrots (Amazona finschi), and Yellow-chevroned Parakeets (Brotogeris chiriri), have become well established in Southern California and a population of mainly Red-masked or Cherry-headed Parakeet/Conure, a female Mitred Parakeet/Conure, and hybrids of those species lives in the surrounding of Telegraph Hill in San Francisco.
Populations of feral Quaker parrots can also be found around St. Petersburg, Florida.