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}} Tinamous form an order (Tinamiformes), comprising a single family (Tinamidae) with two distinct subfamilies, containing 47 species of birds found in Mexico, Central America, and South America. The word "tinamou" comes from the Galibi term for these birds, ''tinamu''. One of the most ancient living groups of bird, they first appear in the fossil record in the Miocene epoch. Tinamous have traditionally been regarded as the sister group of the flightless ratites, but recent work places them well within the ratite radiation, implying basal ratites could fly.〔 They are generally sedentary, ground-dwelling and, though not flightless, when possible avoid flight in favour of hiding or running away from danger. They are found in a variety of habitats, ranging from semi-arid alpine grasslands to tropical rainforests. The two subfamilies are broadly divided by habitat, with the Nothurinae referred to as steppe or open country tinamous, and the Tinaminae known as forest tinamous. Although some species are quite common, tinamous are shy and secretive birds. They are active during the day, retiring to roosts at night. They generally have cryptic plumage, with males and females similar in appearance, though the females are usually larger. They are opportunistic and omnivorous feeders, consuming a wide variety of plant and animal food from fruits and seeds to worms, insects and small vertebrates. They will dust-bathe as well as washing themselves by standing in heavy rain. They are heard more often than seen, communicating with each other by a variety of frequently given, characteristic calls, especially during the breeding season. With occasional exceptions, a male tinamou maintains a territory and a nesting site during the breeding season which a succession of females will visit, laying their eggs in the same nest. Females will wander through several territories mating with, and laying eggs in the nests of, the resident males. Nests are always on the ground, concealed in vegetation or among rocks. Eggs are relatively large and glossy, often brightly colored when laid, and are incubated by the males for a period of 2–3 weeks. The chicks can run soon after hatching and are largely self-sufficient at three weeks old. Tinamous and their eggs have many natural predators, from falcons and vampire bats to jaguars and giant anteaters. They have also been extensively hunted by humans and sometimes persecuted as agricultural pests. However, the main threat to their populations is from habitat destruction through land clearing and agricultural development. Seven species are listed as vulnerable and another seven as near-threatened. They feature in the mythology of the indigenous peoples of their range. Often translocated and easily bred in captivity, they have never been successfully domesticated. ==Taxonomy and systematics== The tinamou family comprises about 47 species in nine genera. The two subfamilies are the Nothurinae (also known as the Rhyncotinae), the steppe tinamous, and the Tinaminae, the forest tinamous. "''Tinamidae''" was defined as by Gauthier and de Queiroz (2001): "''Tinamidae'' refers to the crown clade stemming from the most recent common ancestor of ''Tetrao'' (HREF="http://www.kotoba.ne.jp/word/11/Tinamus" TITLE="Tinamus">Tinamus'' ) ''major'' Gmelin 1789 and all extant birds sharing a more recent ancestor with that species than with ''Struthio camelus'' Linnaeus 1758 and ''Vultur gryphus'' Linnaeus 1758." Their similarity to other ground-dwelling birds such as partridges and megapodes is a result of convergence and symplesiomorphy rather than shared evolutionary innovations. Of Gondwanan origin, tinamous are related to the ratites. Together they make up Palaeognathae ("old jaws"), while all other living birds are members of Neognathae ("new jaws"). Unlike other palaeognaths, tinamous do have a keeled sternum, but like the other palaeognaths they have a distinctive palate. It was formerly believed that the Tinamiformes separated early on due to their retention of a keeled sternum. The tinamous' possession of powder-down feathers and preen glands, which the ratites lack, is another distinguishing characteristic between the two orders. The tinamou family has been shown to be monophyletic.〔 Phylogenomic studies have placed it as the sister group to Australasian and Oceanian ratites (i.e. the cassowaries, emus, and kiwis), thus nesting well with the ratite phylogenetic tree, with the South American rheas and African ostriches as successive outgroups. Research published starting in 2010 has found that tinamous are the sister group to the extinct moa of New Zealand; moa are more distantly related to emus and cassowaries than had been thought previously. These findings imply that evolution of flightlessness occurred independently multiple times in ratite evolution.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Tinamou」の詳細全文を読む スポンサード リンク
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