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The thylacine ( , or , also ;〔("thylacine" ). Dictionary.com Unabridged (v 1.1). Random House, Inc. 30 May 2009.〕 binomial name: ''Thylacinus cynocephalus'', Greek for "dog-headed pouched one") was the largest known carnivorous marsupial of modern times. It is commonly known as the Tasmanian tiger (because of its striped lower back) or the Tasmanian wolf.〔As well as the common alternative names, the thylacine was referred to by a range of other names, which often makes clear identification of the species in historical records difficult. Other names by which it is occasionally identified include marsupial wolf, hyena, zebra wolf, kangaroo wolf, zebra opossum, marsupial tiger, tiger cat, Tasmanian pouched wolf and hyena opossum.〕 Native to continental Australia, Tasmania and New Guinea, it is believed to have become extinct in the 20th century. It was the last extant member of its family, Thylacinidae; specimens of other members of the family have been found in the fossil record dating back to the late Oligocene. The thylacine had become extremely rare or extinct on the Australian mainland before British settlement of the continent, but it survived on the island of Tasmania along with several other endemic species, including the Tasmanian devil. Intensive hunting encouraged by bounties is generally blamed for its extinction, but other contributing factors may have been disease, the introduction of dogs, and human encroachment into its habitat. Despite its official classification as extinct, sightings are still reported, though none has been conclusively proven. Surviving evidence suggests that it was a relatively shy, nocturnal creature with the general appearance of a medium-to-large-size dog, except for its stiff tail and abdominal pouch (which was reminiscent of a kangaroo) and a series of dark transverse stripes that radiated from the top of its back (making it look a bit like a tiger). Like the tigers and wolves of the Northern Hemisphere, from which it obtained two of its common names, the thylacine was an apex predator. As a marsupial, it was not closely related to these placental mammals, but because of convergent evolution it displayed the same general form and adaptations. Its closest living relative is thought to be either the Tasmanian devil or the numbat. The thylacine was one of only two marsupials to have a pouch in both sexes (the other being the water opossum). The male thylacine had a pouch that acted as a protective sheath, covering his external reproductive organs while he ran through thick brush. The thylacine has been described as a formidable predator because of its ability to survive and hunt prey in extremely sparsely populated areas.〔Paddle (2000)〕 The thylacine is a candidate for cloning and other molecular science projects due to its recent demise and the existence of several well preserved specimens.〔(True or False? Extinction Is Forever ) smithsonianmag.com〕 == Evolution == The modern thylacine first appeared about 4 million years ago. Species of the family Thylacinidae date back to the beginning of the Miocene; since the early 1990s, at least seven fossil species have been uncovered at Riversleigh, part of Lawn Hill National Park in northwest Queensland. Dickson's thylacine (''Nimbacinus dicksoni'') is the oldest of the seven discovered fossil species, dating back to 23 million years ago. This thylacinid was much smaller than its more recent relatives. The largest species, the powerful thylacine (''Thylacinus potens'') which grew to the size of a wolf, was the only species to survive into the late Miocene. In late Pleistocene and early Holocene times, the modern thylacine was widespread (although never numerous) throughout Australia and New Guinea. An example of convergent evolution, the thylacine showed many similarities to the members of the dog family, Canidae, of the Northern Hemisphere: sharp teeth, powerful jaws, raised heels and the same general body form. Since the thylacine filled the same ecological niche in Australia as the dog family did elsewhere, it developed many of the same features. Despite this, it is unrelated to any of the Northern Hemisphere predators. 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「Thylacine」の詳細全文を読む スポンサード リンク
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