Trädlevande pungdjur från nya guinea
› djurvardguiden › flygpungekorre. 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.
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 species, which is about 4. Nevertheless, despite the rich biodiversity, New Guinea's megafauna diversity is quite low since the Pleistocene extinction event, especially when it comes to apex predators.
For example, there are only three terrestrial animals at the top of the food chain. Of the three, two are obligate carnivores such as the crocodile monitor and the New Guinea singing dog , whilst one, the cassowary , is actually a frugivore but predatory opportunistically and seasonally. Papua 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 million years ago, and Sahul separated from Antarctica 50 million years ago. As it drifted north, New Guinea moved into the tropics. Throughout Papua 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, years ago. At this time, a number species existed on both land masses, and many plants and animals thus crossed from Australia to Papua New Guinea and vice versa. Many later became isolated as the connection ended, then further evolving to the new environment and becoming distinct species. As Papua 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 Papua New Guinea. This has resulted in a unique mixture of Australian and Asian species, seen nowhere else in the world. A large percentage of Papua New Guinea's species are endemic to the island. Mayr collected several thousand bird skins he named 26 new bird species during his lifetime and, in the process, also named 38 new orchid species.
He determined that New Guinea's rarest birds-of-paradise were, in fact, hybrid species. Mayr's experience of the fauna of New Guinea informed many of his conclusions about evolution for the rest of his life. The mammal fauna of New Guinea is composed of all extant subclasses of mammal: the monotremes , placentals and marsupials. New Guinea contains the largest number of monotreme species of any land mass, with only one species absent: the platypus Ornithorhynchus anatinus.
The marsupial fauna of New Guinea is diverse, consisting of the three orders: Dasyuromorphia , Peramelemorphia and Diprotodontia. The native placental mammals are solely represented by the rodents and bats.
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There are approximately the same number of placental species as marsupials and monotremes. New Guinea's monotremes are restricted to the family Tachyglossidae , also known as echidnas. There are four species of echidnas in two genera: the short-beaked echidna Tachyglossus aculeatus , the eastern long-beaked echidna Zaglossus bartoni , the western long-beaked echidna Zaglossus bruijni and Sir David's long-beaked echidna Zaglossus attenboroughi.
No living Zaglossus have been seen in Australia, in recent years, and this genus may now be endemic to New Guinea, although a specimen in the natural history museum was collected from the Kimberley region in the early 20th century [ 5 ] and fossils have been found in Australia. The native mammal fauna of New Guinea lacks large predators. The largest is the bronze quoll Dasyurus spartacus , a rare quoll , first discovered in southern New Guinea in Fossils of larger marsupials have been found, including the carnivorous thylacine Thylacinus sp.
The kangaroos , Macropodidae, of New Guinea are highly varied in their ecology and behaviour. Those closely related to the Australian kangaroos, such as the agile wallaby Macropus agilis , inhabit the open grasslands of New Guinea.
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However, the tree-kangaroos , which are mostly endemic to New Guinea, are different in appearance and behaviour. As suggested by their name, they are arboreal. They have long, thick tails which enable them to balance in trees, and large, strong forearms for gripping to trees. Two species of tree kangaroos are also found in Australia, they are believed to have migrated from New Guinea during the Pleistocene.
The cuscus, family Phalangeridae, are a family of marsupials closely related to the possums of Australia. The cuscus have evolved in New Guinea, and are found throughout the island. Most species are dark brown or black, however two species, the common spotted cuscus Spilocuscus maculatus and black spotted cuscus Spilocuscus rufoniger , are black, orange and yellow.