Parrot

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For other uses of the word parrot, see Parrot (disambiguation).

Parrots or psittacines (pronounced /ˈsɪtəˌsaɪnz/^[1][2]) is an order (namely Psittaciformes) of birds that includes about 350 species. They are usually grouped into two families: the Cacatuidae (cockatoo), and the Psittacidae (parrots), but one may find many variations. Some sources divide parrots into three families.^[3] (The term "true parrot" is not used by the majority of bird keepers, biologists and lay people and is a source of confusion.)

All members of the order have a generally erect stance and a characteristic curved beak shape with the upper mandible having slight mobility in the joint with the skull. All parrots are zygodactyl, with two toes at the front of each foot and two at the back, and all parrot eggs are white in color.

Parrots can be found in most warm regions of the world, including India, southeast Asia, Southern regions of North America, South America and west Africa. By far the greatest number of parrot species come from Australasia, South America, and Central America. No parrot's natural range currently extends into the United States, although the Carolina Parakeet and Thick-billed Parrot once ranged into southern states.

The order is diverse and contains exceptions (notoriously the Eclectus for sexual dimorphism, and the kakapo for flightlessness, diet & digestion, and lek breeding). However, most parrots are cavity nesters, are minimally or not sexually dimorphic, and seem to be highly social. Along with the Corvidae, the Psittaciformes are generally considered the most intelligent of the birds. Parrots are altricial (their young are helpless at birth) and the larger species breed slowly (K-selection). Extant species range in size from the Buff-faced Pygmy-parrot, at under 10 g and 8 cm (3.2 inches), to the Hyacinth Macaw, at 1.6 kg (3.5 lbs) and 1 meter (3.3 feet).

[edit] Evolution and systematics

[edit] Origins and evolution

In general, an area which has, relative to other areas, a great concentration of different lineages within a particular family is likely to be the original ancestral home of that family.^{[citation needed]} The diversity of Psittaciformes in South America and Australasia suggests that the order has a Gondwanan origin. The parrot family's fossil record, however, is sparse and their origin remains a matter of informed speculation rather than fact.

A single 15 mm fragment from a lower bill (UCMP 143274), found in Lance Creek Formation deposits of Niobrara County, Wyoming, has been suggested as the first parrot fossil. Of Late Cretaceous age, it is about 70 million years old. But subsequent reviews have established that this fossil is almost certainly not from a bird, but from a caenagnathid theropod — a non-avian dinosaur with a birdlike beak.

It is now generally assumed that the Psittaciformes or their common ancestors with a number of related bird orders were present somewhere on the world around the Cretaceous–Tertiary extinction event, some 65 mya (million years ago). If so, they probably had not evolved their morphological autapomorphies yet, but were generalized arboreal birds, roughly similar (though not necessarily closely related) to today's potoos or frogmouths (see also Palaeopsittacus below).

Europe is the origin of the first generally accepted parrot fossils. They date from the Eocene, starting around 50 mya (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 related lineages which evolved in the Northern Hemisphere but have since died out. These are probably not "missing links" between ancestral and modern parrots, but rather psittaciform lineages that evolved parallel to true parrots and cockatoos and had their own peculiar autapomorphies:

• Psittacopes (Early/Middle Eocene of Geiseltal, Germany) — basal?
• Serudaptus - pseudasturid or psittacid?
• Pseudasturidae
  • Pseudasturides - formerly Pseudastur
• Quercypsittidae
  • Quercypsitta (Late Eocene)

The earliest records of modern parrots date to about 23–20 mya and are also from Europe. Subsequently, the fossil record — again, mainly from Europe — consists of bones clearly recognizable as belonging to modern-type parrots. 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 mya. 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 modern cockatoos. A few modern genera are tentatively dated to a Miocene origin, but their unequivocal record stretches back only some 5 million years (see genus articles for more).

The named fossil genera of parrots are probably all in the Psittacidae or close to its ancestry:

• Archaeopsittacus (Late Oligocene/Early Miocene)
• Xenopsitta (Early Miocene of Czechia)
• Bavaripsitta (Middle Miocene of Steinberg, Germany)
• "Pararallus dispar" (Middle Miocene of France) - includes "Psittacus" lartetianus

Some Paleogene fossils are not unequivocally accepted to be of psittaciforms:

• Palaeopsittacus (Early - Middle Eocene of NW Europe) - caprimulgiform (podargid?) or quercypsittid?
• "Precursor" (Early Eocene of England) - psittaciform (in part - several species? pseudasturid or psittacid?)
• Pulchrapollia (Early Eocene) — includes "Primobucco" olsoni - psittaciform (pseudasturid or psittacid)?

[edit] 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.

The Psittaciformes are generally considered to consist of two major living 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. However, the actual situation may be more complex (see below).

While understanding of the relationships between subgroups of true parrots — for example, 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, it is difficult to determine how distinct the various lineages are really from each other, and how fast and radically they were changed by evolution.

Lorikeets were previously regarded as a third family Loriidae,^[3] though now most often considered a subfamily of the Psittacidae.^[4] Others lump all Psittaciformes into one giant family.^{[citation needed]} The present majority view 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 more closely related lineages. Biogeography suggests that the lorikeets are best considered a uniquely distinct lineage, not as divergent as cockatoos maybe, but still standing apart from other psittacids.

Recent molecular studies, such as that of mtDNA in 1998,^[5] or the sex chromosome spindlin gene in 2005,^[6] find the relationships of the main lineages of living parrots to be for the most part unresolvable with any confidence. An unexpected^[7] result was that according to the spindlin sequence data, the only major divergence among living parrots that could be reliably positioned in the calculated phylogenies occurred between some New Zealand parrots - Kakapo, Kākā and Kea - and the remaining psittaciformes.

The case for distinctness of at least the nestorines seems to be fairly complete by now. Its position - with or without the kakapo - and ancient age as suggested by the molecular data is at odds with the fossil record though, as it would require an absurdly high degree of homoplasy and a decidedly non-parsimonious character distribution in living parrots. As the study relies upon an obsolete molecular clock model uncalibrated by material evidence, the results are highly spurious. The scenario of Miyaki et al. (1998),^[5] while less complete (and excluding the kakapo) agrees better, though not completely, with the material evidence. Again, an unreliable molecular clock model was used.

While the latter two seem indeed to constitute a distinct lineage, placement of the kakapo with these is contradicted by mtDNA cytochrome b sequence data.^[5] In any case, the major lineages of psittacines seem indeed to represent distinct clades, but their relationship among them is not well resolvable by the present molecular data. They appear to have radiated throughout a fairly limited timespan, approximately during the Eocene. One finding of major importance is that neither cockatoos nor lories seem to be as distinct from other major parrot lineages as they are usually assumed to be.

[edit] Systematics

• A list of all parrots sortable by common or binomial name.

• 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 (as in the taxobox above).

• Below is a version of the latter in which more subfamilies are recognized. Molecular data (see above) suggests that several subfamilies might indeed be valid and perhaps even be elevated to family rank, but arrangement of tribes in these is not well resolved at present.

Family Psittacidae: true parrots, over 300 species

• Subfamily Arinae: Neotropical parrots, about 150 species in some 30 genera. Probably 2 distinct lineages:^[5][6]
• Subfamily Loriinae: Around a dozen genera with some 50 species of lorikeets and lories, centered in New Guinea, spreading to Australia, Indonesia, and the islands of the south Pacific.
• Subfamily Micropsittinae: 6 species of pygmy parrot, all in a single genus.
• Subfamily Nestorinae: 1 genus with only 2 living species, the Kea and Kākā of the New Zealand region.
• Subfamily Psittacinae
  • Tribe Cyclopsittacini: fig parrots, 3 genera, all from New Guinea or nearby.
  • Tribe Polytelini: three genera from Australia and the Wallacea. - may belong to broad-tailed parrots
  • Tribe Psittrichadini: A single species, Pesquet's Parrot.
  • Tribe Psittacini: Afrotropical parrots, about a dozen species in 3 genera.
  • Tribe Psittaculini: Paleotropic psittaculine parrots, nearly 70 living species in 12 genera, distributed from India to Australasia.
• Subfamily Platycercinae: Broad-tailed parrots; nearly 30 species in roughly one dozen genera.
  • Tribe Melopsittacini: one genus with one species, the Budgerigar
  • Tribe Neophemini: two small genera of parrots.
  • Tribe Pezoporini: one genus of parrots with two quite distinct species.
  • Tribe Platycercini: Rosellas and relatives; around 20 species in 8 genera.
• Subfamily Strigopinae: The flightless, nearly extinct Kakapo of New Zealand.

[edit] Diet

The diet of parrots consists of seeds, fruit, nectar and pollen and to a lesser degree animal prey. Without question the most important of these to most true parrots and cockatoos are seeds. The evolution of the large and powerful bill can be explained primarily as an adaptation to opening and consuming seeds. All true parrots except the Pesquet's Parrot employ the same method to obtain the seed from the husk; the seed is held between the mandibles and the lower mandible crushes the husk, whereupon the seed is rotated in the bill and the remaining husk is removed. A foot is sometimes used in order to help holding large seeds in place. Parrots are seed predators rather than seed dispersers; and in many cases where species are recorded as consuming fruit they are only eating the fruit in order to get at the seed. As seeds often have poisons to protect them parrots will consume clay in order to filter the toxic compounds.^[8] - The lorikeets, Swift Parrot and Philippine Hanging Parrot are primarily nectar and pollen consumers, and have tongues with brush tips to collect this source of food, as well as some changes in the gut.^[9] Many other species also consume nectar as well when it becomes available.

In addition to feeding on seeds and flowers, some parrot species will prey on animals. Golden-winged Parakeets prey on water snails, and famously the Keas of New Zealand will scavenge on sheep carcases and even kill juvenile petrels. Another New Zealand parrot, the Antipodes Island Parakeet, enters the burrows of nesting Grey-backed Storm-petrels and kills the incubating adults.^[10] Some cockatoos and the Kākā will also excavate branches and wood in order to obtain grubs.

[edit] Intelligence

Studies with captive birds have given us insight into which birds are the most intelligent. While parrots have the distinction of being able to mimic human speech, studies with the African Grey Parrot have shown that some are able to associate words with their meanings and form simple sentences (see Alex and N'kisi). Along with crows, ravens, and jays (family Corvidae), parrots are considered the most intelligent of birds. The brain-to body size ratio of psittacines and corvines is actually comparable to that of higher primates.^[11] One argument against the supposed intelligent capabilities of bird species is that birds have a relatively small cerebral cortex, which is the part of the brain considered to be the main area of intelligence in other animals. However, it seems that birds use a different part of their brain, the medio-rostral neostriatum/hyperstriatum ventrale, as the seat of their intelligence. Not surprisingly, research has shown that these species tend to have the largest hyperstriata, and Dr. Harvey J. Karten, a neuroscientist at UCSD who has studied the physiology of birds, discovered that the lower part of avian brains are similar to ours. In Animal Planet's program "Most Extreme Animals: Smartest", parrots were ranked #1 as the world's smartest animals. Not only have parrots demonstrated intelligence through scientific testing of their language using ability, but some species of parrot such as the Kea are also highly skilled at using tools and solving puzzles.^[12]

[edit] Sound imitation and speech

Main article: Talking birds

See also: Animal language

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. A second example is that of N'kisi, another African grey, which has been shown to have a vocabulary of approximately a thousand words and has displayed an ability to invent as well as use words in context and in the correct tense.^[13]

Parrots do not have vocal cords, so sound is accomplished by expelling air across the mouth of the bifurcated trachea. Different sounds are produced by changing the depth and shape of trachea. So, talking parrots are really whistling in different variations. Congo African Grey Parrots (CAG) are well known for their ability to "talk", which may be caused by more control, or stronger trachea. But that does not mean that a Cockatiel (Cockatiels are not well known for their talking ability), could have a greater vocabulary than an African Grey Parrot.

This ability has made them prized as pets from ancient time to now. In The Masnavi, a writing by an author from Afghanistan, 1250 CE, the author talks about an ancient method for training parrots to speak.

"Parrots are taught to speak without understanding the words. The method is to place a mirror between the parrot and the trainer. The trainer, hidden by the mirror, utters the words, and the parrot, seeing his own reflection in the mirror, fancies another parrot is speaking, and imitates all that is said by the trainer behind the mirror."

[edit] Parrots and humans

[edit] Threats and conservation

A large number of parrot species are in decline, many species are already extinct. CITES, discussed below, lists 55 parrot species as endangered.^[14] An example of a nearly extinct species is the Spix's Macaw, Cyanopsitta spixi and an extinct species is the Cuban Macaw, Ara tricolor. Many species depend on habitat that human beings turn into timberland and farmland. Climate change alters habitats, such as turning scrub land into desert and can be just as bad as cutting down forest.

Loss of habitat and the pet trade are the largest causes of decline in wild populations. However, national and international laws that protect parrots are being established. Most notably is CITES, The Convention on the International Trade in Endangered Species, that regulates the international trade of all wild caught listed parrot species; highly endangered species are protected on the CITES appendix 1 list, and all the other species are protected on the CITES appendix 2 list of vulnerable species.

There are many active conservation groups whose goal is the conservation of wild populations. These groups tend to be supported most by pet owners who care deeply about parrots. One of the largest includes The World Parrot Trust, an international organization. The group gives assistance to worthwhile projects as well as producing a publication and raising funds through donations and memberships. They state they've helped conservation work in 22 countries. On a smaller scale local parrot clubs (or hookbill clubs as they're called,) will raise money to donate to a cause of conservation. Zoo and wildlife centers usually provide public education, to change habits that cause damage to wild populations. A popular attraction that many zoos now employ is a lorikeet feeding station, where visitors feed small parrots with cups of liquid food. This is usually done in association with educational signs and lecture.

[edit] Parrots as pets

See also: Companion parrot

Parrots have historically been kept captive in many cultures. Europeans kept birds matching the description of the Rose-ringed Parakeet (or called the ring-necked parrot.) Such as in this first century account by Pliny the Elder [2]. As they have been prized for thousands of years for their beauty and ability to talk, they have also proven hard to care for. For example, author Wolfgang de Grahl discusses in his 1987 book "The Grey Parrot," that some importers allowed parrots to drink only coffee while they were being shipped by boat considering pure water to be detrimental and believing that their actions would increase survival rates during shipping. (These days is commonly accepted that the caffeine in coffee is toxic to birds.)

Captive parrots can be kept in a cage or aviary. Some are wing-clipped. Depending on locality parrots may be either wild caught or be captive bred. They require feeding, grooming, veterinary care, and environmental enrichment through the provision of toys. Some parrot species, including large cockatoos, Amazon, and macaws, have very long life-spans with 80 years being reported and record ages of over one hundred. Other parrots, such as love birds and hanging parrots have short life spans.

Parrots types that are commonly kept as pets include conures, macaws, Amazons, cockatoos, African Greys, lovebirds, cockatiels, budgerigars, eclectus, and parakeets. Each species of bird has different needs.

In 1992 the newspaper USA Today published that there were 11 million pet birds in the United States alone.

King Tut, a salmon-crested (aka Moluccan) cockatoo, arrived at the San Diego Zoo on May 25, 1925, and served as the zoo's official greeter from 1951 until his retirement in 1989. 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 World War II; the aged parrot, called Charlie, was reputed to curse the Nazis and Adolf Hitler.^{[citation needed]} Subsequent research strongly suggested that the parrot had never belonged to Winston Churchill,^[15][16] although Charlie's great age was not in question.

[edit] Trade of parrots

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. A combination of trapping of wild birds and damage to parrot habitats makes survival difficult or even impossible for some species of parrot.

The trade continues unabated in some countries. A report published in January 2007, titled The Illegal Parrot Trade in Mexico: A Comprehensive Assessment, presents a clear picture of the wild-caught parrot trade in Mexico, stating: "The majority of parrots captured in Mexico stay in the country for the domestic trade. A small percentage of this capture, 4% to 14%, is smuggled into the USA."

The scale of the problem can be seen in the Tony Silva case of 1996, in which a parrot expert and former director at Tenerife's Loro Parque (Europe's largest parrot park) was jailed in the United States for 82 months and fined $100,000 for smuggling Hyacinth Macaws. ^[17] (Such birds command a very high price.) The case led to calls for greater protection and control over trade in the birds. Loro Parque has since become well known for parrot conservation work.^[18]

Different nations have different methods of handling internal and international trade. Australia has banned the export of its native birds since 1960. Some believe this protects rare species because the common species will be targeted for smuggling due to demand created by the ban. The United States protects its only native parrot through its Endangered Species Act, and protects other nations' birds through its Wild Bird Conservation Act. There are no national laws regarding its multiple feral populations. Mexico has a licensing system for capturing and selling native birds (though the laws are not well enforced).

[edit] Parrots and culture

Parrots have feature in human writings, story, art, humor, religion and music for thousands of years. Recent books about parrots in human culture include Parrot Culture [3].

In ancient times and currently parrot feathers have been used in ceremonies, and the "idea" of the parrot has been used to represent the human condition in medieval literature. They also have a long history as pets.

Currently parrots feature in many media. There are magazines devoted to parrots as pets (Bird Talk), and conservation of parrots (PsittaScene). Recent fictional books featuring parrots include Next. Fictional films include Paulie, and documentaries include The Wild Parrots of Telegraph Hill.

[edit] Feral populations

See also: Feral parrots

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.

Budgerigar Feral Budgerigars have existed since the 1940s in the St Petersburg, Florida area of the United States, but have decreased since the early 1980s. Colder than normal winter temperatures in some years and increased competition from European Starlings appear to be the main reasons for the declining population.

Rainbow Lorikeet Feral colonies of Rainbow Lorikeet (Trichoglossus haematodus) have been established in Perth, Western Australia^[19] and in Auckland, New Zealand.

Eastern Rosella The Eastern Rosella (Platycercus eximius) has become naturalized in the North Island of New Zealand.^[20]

Rose-ringed Parakeet 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^{[citation needed]}) to have descended from escaped or released pets. The largest UK roost of these is thought to be in Esher, Surrey, numbering several thousand. Feral Rose-ringed Parakeets also occur in the United States and South Africa.

Alexandrine Parakeet Often flocking with the naturalized P. krameri populations in Belgium and England are smaller populations of Alexandrine Parakeets (Psittacula eupatria).

Monk Parakeet Populations of the Monk Parakeet (Myiopsitta monachus) have established themselves in many areas of the United States and Spain.

Other Also found in the United States are various naturalized Brotogeris spp. (mainly B. versicolurus (Canary-winged Parakeet a.k.a. White-winged Parrot) and/or B. chiriri (Yellow-chevroned Parakeet/Parrot). Brooklyn, New York, in New York City, is home to a population of Myiopsitta monachus (monk aka Quaker Parakeet/Parrot).^[21] A population of naturalized Rose-collared aka Peach-faced Lovebirds (Agapornis roseicollis) are found 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 thus several inter-specific hybrids live in the area of Telegraph Hill in San Francisco. Many states in the U.S. have now enacted laws banning some of the above species & most particularly monk (aka quaker) Parakeet/Parrot from being sold, bred, or kept as pets.

[edit] References and footnotes