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The fauna of New Guinea comprises a large number of species of mammals, reptiles, birds, fish, invertebrates and amphibians. As the world’s largest and highest tropical island, New Guinea occupies less than 0.5% of world's land surface, yet supports a high percentage of global biodiversity. Approximately 4,642 vertebrate species inhabit the island of New Guinea and its surrounding waters, which constitutes about 8% of the recognized world vertebrates. This ranges from an estimated 4% of the world's lizards and mammals, to about 10% of the world's fish species. The numbers of global and New Guinea invertebrate species are poorly known, and thus an accurate comparison is difficult. Butterflies are the best known invertebrate group, and are represented in New Guinea by about 735 species, which is about 4.2% of the world total of 17,500 species.〔 ==Origin== New Guinea is a large island located north of Australia, and south-east of Asia. It is part of the Australian Plate, known as Sahul, and once formed part of the supercontinent Gondwana. The origin of most New Guinea fauna is closely linked to Australia. Gondwana began to break up 140 million years ago, and Sahul separated from Antarctica 50 million years ago. As it drifted north, New Guinea moved into the tropics. Throughout New Guinea's geological history there have been many land connections with Australia. These have occurred during glaciations in various ice ages. Four occurred during the Pleistocene; the last of which was severed 10,000 years ago. At this time, a number species existed on both land masses, and many plants and animals thus crossed from Australia to New Guinea and vice versa. Many later became isolated as the connection ended, then further evolving to the new environment and becoming distinct species. However, this Australia-New Guinea mixing occurred among a relatively few faunal groups; some New Guinea species have an Asian origin. As New Guinea drifted north, it collided with the Pacific Plate as well as a number of oceanic islands. Although no land connection with Asia was ever formed (see Wallace line), the proximity between the land masses, via the many small islands of the Indonesian archipelago, allowed some Asian species to migrate to New Guinea. This has resulted in a unique mixture of Australian and Asian species, seen nowhere else in the world. A large percentage of New Guinea's species are endemic to the island. 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「Fauna of New Guinea」の詳細全文を読む スポンサード リンク
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