ParrotParrots, also known as psittacines (ˈsɪtəsaɪnz), are birds of the order Psittaciformes (ˈsɪtəsᵻfɔrmiːz) and are found mostly in tropical and subtropical regions. They are made up of four families that contain roughly 410 species in 101 genera. The four families are: Psittaculidae (Old World parrots) , the Psittacidae (African and New World parrots), the Cacatuoidea (cockatoos), and the Strigopidae (New Zealand parrots). One-third of all parrot species are threatened by extinction, with higher aggregate extinction risk (IUCN Red List Index) than any other comparable bird group.
Haast's eagleHaast's eagle (Hieraaetus moorei) is an extinct species of eagle that lived in the South Island of New Zealand, commonly accepted to be the pouakai of Māori legend. It was the largest eagle known to have existed, with an estimated weight of , compared to the harpy eagle. Its massive size is explained as an evolutionary response to the size of its prey, the flightless moa, the largest of which could weigh . Haast's eagle became extinct around 1400, following the arrival of the Māori, who outcompeted it for its moa prey.
New ZealandNew Zealand (Aotearoa aɔˈtɛaɾɔa) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island (Te Ika-a-Māui) and the South Island (Te Waipounamu)—and over 700 smaller islands. It is the sixth-largest island country by area and lies east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps, owe much to tectonic uplift and volcanic eruptions.
Bird anatomyBird anatomy, or the physiological structure of birds' bodies, shows many unique adaptations, mostly aiding flight. Birds have a light skeletal system and light but powerful musculature which, along with circulatory and respiratory systems capable of very high metabolic rates and oxygen supply, permit the bird to fly. The development of a beak has led to evolution of a specially adapted digestive system. Birds have many bones that are hollow (pneumatized) with criss-crossing struts or trusses for structural strength.
Island gigantismIsland gigantism, or insular gigantism, is a biological phenomenon in which the size of an animal species isolated on an island increases dramatically in comparison to its mainland relatives. Island gigantism is one aspect of the more general "island effect" or "Foster's rule", which posits that when mainland animals colonize islands, small species tend to evolve larger bodies, and large species tend to evolve smaller bodies (insular dwarfism).
Kiwi (bird)Kiwi (ˈkiːwi: ) are flightless birds endemic to New Zealand of the order Apterygiformes. The five extant species fall into the family Apterygidae (ˌæptəˈrɪdʒədi:) and genus Apteryx (ˈæptərɪks). Approximately the size of a domestic chicken, kiwi are the smallest ratites (which also include ostriches, emus, rheas, cassowaries and the extinct elephant birds and moas). DNA sequence comparisons have yielded the conclusion that kiwi are much more closely related to the extinct Malagasy elephant birds than to the moa with which they shared New Zealand.
Holocene extinctionThe Holocene extinction, or Anthropocene extinction, is the ongoing extinction event during the Holocene epoch. The extinctions span numerous families of plants and animals, including mammals, birds, reptiles, amphibians, fish, invertebrates, and affecting not just terrestrial species but also large sectors of marine life. With widespread degradation of biodiversity hotspots, such as coral reefs and rainforests, as well as other areas, the vast majority of these extinctions are thought to be undocumented, as the species are undiscovered at the time of their extinction, which goes unrecorded.
