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The numbat (''Myrmecobius fasciatus''), also known as the banded anteater, marsupial anteater, or ''walpurti'', is a marsupial found in Western Australia. Its diet consists almost exclusively of termites. Once widespread across southern Australia, its range is now restricted to several small colonies, and it is listed as an endangered species. The numbat is an emblem of Western Australia and protected by conservation programs. ==Classification== The numbat genus ''Myrmecobius'' is the sole member of the family Myrmecobiidae, one of the three families that make up the order Dasyuromorphia, the Australian marsupial carnivores.〔 The species is not closely related to other extant marsupials; the current arrangement in the Dasyuromorphia order places its monotypic family with the diverse and carnivorous species of Dasyuridae. A closer affinity with the extinct thylacine, contained in the same order, has been proposed. Genetic studies have shown the ancestors of the numbat diverged from other marsupials between 32 and 42 million years ago, during the late Eocene. Two subspecies are recognized, but one of these, the rusty numbat (''M. f. rufus''), has been extinct since at least the 1960s, and only the nominate subspecies (''M. f. fasciatus'') remains alive today. As its name implies, the rusty numbat was said to have a more reddish coat than the surviving subspecies.〔 Only a very small number of fossil specimens are known, the oldest dating back to the Pleistocene, and no fossils belonging to other species from the same family have yet been discovered.〔 ==Description== The numbat is a small, colourful creature between long, including the tail, with a finely pointed muzzle and a prominent, bushy tail about the same length as its body. Colour varies considerably, from soft grey to reddish-brown, often with an area of brick red on the upper back, and always with a conspicuous black stripe running from the tip of the muzzle through the eyes to the bases of the small, round-tipped ears. Between four and eleven white stripes cross the animal's hindquarters, which gradually become fainter towards the midback. The underside is cream or light grey, while the tail is covered with long, grey hair flecked with white. Weight varies between . Unlike most other marsupials, the numbat is diurnal, largely because of the constraints of having a specialised diet without having the usual physical equipment for it. Most ecosystems with a generous supply of termites have a fairly large creature with powerful forelimbs bearing heavy claws.〔 Numbats are not large, and they have five toes on the fore feet, and four on the hind feet.〔 However, like other mammals that eat termites or ants, the numbat has a degenerate jaw with up to 50 very small, nonfunctional teeth, and although it is able to chew,〔 rarely does so, because of the soft nature of its diet. Uniquely among terrestrial mammals, an additional cheek tooth is located between the premolars and molars; whether this represents a supernumerary molar tooth or a deciduous tooth retained into adult life is unclear. As a result, although not all individuals have the same dental formula, in general, it follows the unique pattern: 〔 Like many ant-eating animals, the numbat has an unusually long, narrow tongue, coated with sticky saliva produced by large submandibular glands. A further adaptation to the diet is the presence of numerous ridges along the soft palate, which apparently help to scrape termites off the tongue so they can be swallowed. The digestive system is relatively simple, and lacks many of the adaptations found in other entomophagous animals, presumably because termites are easier to digest than ants, having a softer exoskeleton. Numbats are apparently able to gain a considerable amount of water from their diets, since their kidneys lack the usual specialisations for retaining water found in other animals living in their arid environment. Numbats also possess a sternal scent gland, which may be used for marking their territories.〔 Although the numbat finds termite mounds primarily using scent, it has the highest visual acuity of any marsupial, and, unusually for marsupials, has a high proportion of cone cells in the retina. These are both likely adaptations for its diurnal habits, and vision does appear to be the primary sense used to detect potential predators.〔 Numbats regularly enter a state of torpor, which may last up to fifteen hours a day during the winter months. 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「numbat」の詳細全文を読む スポンサード リンク
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