[5] Parrots—along with ravens, crows, jays, and magpies—are among the most intelligent birds, and the ability of some species to imitate human speech enhances their popularity as pets.

[10] A single 15 mm (0.6 in) fragment from a large lower bill (UCMP 143274), found in deposits from the Lance Creek Formation in Niobrara County, Wyoming, had been thought to be the oldest parrot fossil and is presumed to have originated from the Late Cretaceous period, which makes it about 70 million years old.

Initially, a neoavian named Mopsitta tanta, uncovered in Denmark's Early Eocene Fur Formation and dated to 54 mya, was assigned to the Psittaciformes.

[41] Parrots have strong zygodactyl feet (two toes facing forward and two back) with sharp, elongated claws, which are used for climbing and swinging.

Most species are capable of using their feet to manipulate food and other objects with a high degree of dexterity, in a similar manner to a human using their hands.

[49] The lories and lorikeets range from Sulawesi and the Philippines in the north to Australia and across the Pacific as far as French Polynesia, with the greatest diversity being found in and around New Guinea.

[48] The subfamily Arinae encompasses all the neotropical parrots, including the amazons, macaws, and conures, and ranges from northern Mexico and the Bahamas to Tierra del Fuego in the southern tip of South America.

[48] The centre of cockatoo biodiversity is Australia and New Guinea, although some species reach the Solomon Islands (and one formerly occurred in New Caledonia),[54] Wallacea and the Philippines.

[62] The only parrot to inhabit alpine climates is the kea, which is endemic to the Southern Alps mountain range on New Zealand's South Island.

Many species in the Americas, Africa, and Papua New Guinea consume clay, which releases minerals and absorbs toxic compounds from the gut.

In Psittacidae parrots' common breeding displays, usually undertaken by the male, include slow, deliberate steps known as a "parade" or "stately walk" and the "eye-blaze", where the pupil of the eye constricts to reveal the edge of the iris.

Generalists and specialists generally become independent of their parents much quicker than partly specialised species who may have to learn skills over long periods as various resources become seasonally available.

[64] In a similar fashion, captive birds in zoo collections or pets can, if deprived of stimuli, develop stereotyped and harmful behaviours like self-plucking.

[92] Grey parrots are known for their superior ability to imitate sounds and human speech, which has made them popular pets since ancient times.

[94] Besides imitation, it is possible that parrots could be trained to use simple communication tools, e.g., to request food or a favourite activity by pushing a button.

Although parrots can be very affectionate and cute when immature, they often become aggressive when mature (partly due to mishandling and poor training) and may bite, causing serious injury.

The parrots' ability to mimic human words and their bright colours and beauty prompt impulse buying from unsuspecting consumers.

Europeans kept birds matching the description of the rose-ringed parakeet (or called the ring-necked parrot), documented particularly in a first-century account by Pliny the Elder.

[108] Parrots that are bred for pets may be hand-fed or otherwise accustomed to interacting with people from a young age to help ensure they become tame and trusting.

[110] The popularity, longevity, and intelligence of many of the larger kinds of pet parrots and their wild traits such as screaming, has led to many birds needing to be rehomed during the course of their long lifespans.

A common problem is that large parrots that are cuddly and gentle as juveniles mature into intelligent, complex, often demanding adults who can outlive their owners, and can also become aggressive or even dangerous.

[116] To motivate parrots participating in the pilot study, researchers used treats such as peanut butter, yoghurt and pine nuts; one bird responded better to "cheering and praise".

[122] Prior to an earlier temporary ban started in late October 2005, the EU was importing about two million live birds a year, about 90% of the international market: hundreds of thousands of these were parrots.

Also clichés such as the British expression "sick as a parrot" are given; although this refers to extreme disappointment rather than illness, it may originate from the disease of psittacosis, which can be passed to humans.

[149] In Chinese Buddhist iconography, a parrot is sometimes depicted hovering on the upper right side Guan Yin clasping a pearl or prayer beads in its beak.

For a time, Argentina offered a bounty on monk parakeets for that reason, resulting in hundreds of thousands of birds being killed, though apparently this did not greatly affect the overall population.

Many parrots occur only on islands and are vulnerable to introduced species such as rats and feral cat, as they lack the appropriate antipredator behaviours needed to deal with predators.

[158] Island species, such as the Puerto Rican amazon, which have small populations in restricted habitats, are also vulnerable to natural events, such as hurricanes.

The group gives assistance to worthwhile projects, as well as producing a magazine (PsittaScene)[162] and raising funds through donations and memberships, often from pet parrot owners.

[171] All other parrot species, aside from the rosy-faced lovebird, budgerigar, cockatiel and rose-ringed parakeet (which are not included in the appendices) are protected on Appendix II of CITES.