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.
MoaMoa (order Dinornithiformes) are an extinct group of flightless birds formerly endemic to New Zealand. During the Late Pleistocene-Holocene, there were nine species (in six genera). The two largest species, Dinornis robustus and Dinornis novaezelandiae, reached about in height with neck outstretched, and weighed about while the smallest, the bush moa (Anomalopteryx didiformis), was around the size of a turkey. Estimates of the moa population when Polynesians settled New Zealand circa 1300 vary between 58,000 and approximately 2.
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).
GallirallusGallirallus is a genus of rails that live in the Australasian-Pacific region. The genus is characterised by an ability to colonise relatively small and isolated islands and thereafter to evolve flightless forms, many of which became extinct following Polynesian settlement. Following recent taxonomic revisions, there is only one known extant species in this genus along with several extinct species of dubious classification, with all other species being moved to Hypotaenidia, Cabalus, or Aptenorallus.
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.
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.
OstrichOstriches are large flightless birds. They are the heaviest living birds, and lay the largest eggs of any living land animal. With the ability to run at 70 km/h (43.5 mph), they are the fastest birds on land. They are farmed worldwide, with significant industries in the Philippines and in Namibia. Ostrich leather is a lucrative commodity, and the large feathers are used as plumes for the decoration of ceremonial headgear. Ostrich eggs have been used by humans for millennia.
GalliformesGalliformes ˌgælᵻˈfɔrmiːz is an order of heavy-bodied ground-feeding birds that includes turkeys, chickens, quail, and other landfowl. Gallinaceous birds, as they are called, are important in their ecosystems as seed dispersers and predators, and are often reared by humans for their meat and eggs, or hunted as game birds.
Bird flightBird flight is the primary mode of locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding, avoiding predators, and migrating. Bird flight is one of the most complex forms of locomotion in the animal kingdom. Each facet of this type of motion, including hovering, taking off, and landing, involves many complex movements. As different bird species adapted over millions of years through evolution for specific environments, prey, predators, and other needs, they developed specializations in their wings, and acquired different forms of flight.
Great aukThe great auk (Pinguinus impennis) is a species of flightless alcid that became extinct in the mid-19th century. It was the only modern species in the genus Pinguinus. It is not closely related to the birds now known as penguins, which were discovered later by Europeans and so named by sailors because of their physical resemblance to the great auk. It bred on rocky, remote islands with easy access to the ocean and a plentiful food supply, a rarity in nature that provided only a few breeding sites for the great auks.
