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The short-beaked echidna (''Tachyglossus aculeatus'') is one of four living species of echidna and the only member of the genus ''Tachyglossus''. The short-beaked echidna is covered in fur and spines and has a distinctive snout and a specialized tongue, which it uses to catch its prey at a great speed. Like the other extant monotremes, the short-beaked echidna lays eggs; the monotremes are the only group of mammals to do so. This echidna has extremely strong front limbs and claws due to its mechanical advantage which allows it to burrow quickly with great power. As it needs to be able to survive underground, it has a significant tolerance to high levels of carbon dioxide and low levels of oxygen. It has no weapons or fighting ability but repels predators by curling into a ball and deterring them with its spines. The echidna lacks the ability to sweat and cannot deal with heat well, so it tends to avoid daytime activity in hot weather. It can swim if needed. The snout has mechanical and electroreceptors that help the echidna to detect what is around it. During the winter, it goes into deep torpor and hibernation, reducing its metabolism to save energy. As the temperature increases, it emerges to mate. Female echidnas lay one egg a year and the mating period is the only time the otherwise solitary animals meet one another; the male has no further contact with the female or his offspring after mating. A young echidna is the size of a grape but grows rapidly on its mother's milk, which is very rich in nutrients. Baby echidnas eventually grow too large and spiky to stay in the pouch and, at around six months of age, they leave the burrow and have no more contact with their mothers. The species is found throughout Australia, where it is the most widespread native mammal, and in coastal and highland regions of southwestern New Guinea, where it is known as the ''mungwe'' in the Daribi and Chimbu languages.〔Flannery, T. 1990. ''Mammals of New Guinea'' Robert Brown & Associates ISBN 1-86273-029-6〕 It is not threatened with extinction, but human activities, such as hunting, habitat destruction, and the introduction of foreign predatory species and parasites, have reduced the distribution of the short-beaked echidna in Australia. The Currumbin Wildlife Sanctuary, based on the Gold Coast Queensland Australia, has been a world leader in conducting a successful captive breeding program with four puggles being born in 2012. Successful matings have occurred since then and studies continue. ==Taxonomy and naming== The short-beaked echidna was first described by George Shaw in 1792. He named the species ''Myrmecophaga aculeata'', thinking that it might be related to the giant anteater. Since Shaw first described the species, its name has undergone four revisions: from ''M. aculeata'' to ''Ornithorhynchus hystrix'', ''Echidna hystrix'', ''Echidna aculeata'' and finally, ''Tachyglossus aculeatus''.〔〔Iredale, T. and Troughton, E. 1934. A checklist of mammals recorded from Australia. ''Memoirs of the Australian Museum'' 6: i–xii, 1–122〕 The name ''Tachyglossus'' means "quick tongue",〔 in reference to the speed with which the echidna uses its tongue to catch ants and termites,〔 and ''aculeatus'' means "spiny" or "equipped with spines".〔Augee, Gooden and Musser, p. 5.〕 The short-beaked echidna is the only member of its genus, sharing the family Tachyglossidae with the extant species of the genus ''Zaglossus'' that occur in New Guinea.〔Augee, Gooden and Musser, pp. 5–9.〕 ''Zaglossus'' species, which include the western long-beaked, Sir David's long-beaked and eastern long-beaked echidnas, are all significantly larger than ''T. aculeatus'', and their diets consist mostly of worms and grubs rather than ants and termites.〔Augee, Gooden and Musser, pp. 7–10.〕 Species of the Tachyglossidae are egg-laying mammals; together with the related family Ornithorhynchidae, they are the only extant monotremes in the world.〔Augee, Gooden and Musser, p. 10.〕 The five subspecies of the short-beaked echidna are each found in different geographical locations. The subspecies also differ from one another in their hairiness, spine length and width, and the size of the grooming claws on their hind feet.〔Augee, Gooden and Musser, pp. 6–7.〕 * ''T. a. acanthion'' is found in Northern Territory and Western Australia. * ''T. a. aculeatus'' is found in Queensland, New South Wales, South Australia and Victoria.〔 * ''T. a. lawesii'' is found in coastal regions and the highlands of New Guinea, and possibly in the rainforests of Northeast Queensland.〔Griffiths, M.E. 1978. ''The Biology of Monotremes''. Academic Press : New York ISBN 0-12-303850-2〕 * ''T. a. multiaculeatus'' is found on Kangaroo Island. * ''T. a. setosus'' is found on Tasmania and some islands in Bass Strait.〔 The earliest fossils of the short-beaked echidna date back around 15 million years ago to the Pleistocene era, and the oldest specimens were found in caves in South Australia, often with fossils of the long-beaked echidna from the same period. The ancient short-beaked echidnas are considered to be identical to their contemporary descendants except the ancestors are around 10% smaller.〔〔Augee, Gooden and Musser, p. 16.〕 This "post-Pleistocene dwarfing" affects many Australian mammals.〔 Part of the last radiation of monotreme mammals, echidnas are believed to have evolutionally diverged from the platypus around 66 million years ago, between the Cretaceous and Tertiary periods.〔 However, the echidna's pre-Pleistocene heritage has not been traced yet, and the lack of teeth on the fossils found thus far have made it impossible to use dental evidence.〔Augee, Gooden and Musser, pp. 16–17.〕 The short-beaked echidna was commonly called the spiny anteater in older books, though this term has fallen out of fashion since the echidna bears no relation to the true anteaters. It has a variety of names in the indigenous languages of the regions where it is found. The Noongar people from southwestern Western Australia call it the ''nyingarn''. In Central Australia southwest of Alice Springs, the Pitjantjatjara term is ''tjilkamata'' or ''tjirili'', from the word ''tjiri'' for spike of porcupine grass ''(Triodia irritans)''. The word can also mean slowpoke. In central Cape York Peninsula, it is called ''(minha) kekoywa'' in Pakanh, where ''minha'' is a qualifier meaning 'meat' or 'animal', ''(inh-)ekorak'' in Uw Oykangand and ''(inh-)egorag'' in Uw Olkola, where ''inh-'' is a qualifier meaning 'meat' or 'animal'. In the highland regions of southwestern New Guinea, it is known as the ''mungwe'' in the Daribi and Chimbu languages.〔 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「Short-beaked echidna」の詳細全文を読む スポンサード リンク
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