Australia was once part of the southern supercontinent Gondwanawhich also included South America, Africa, India and Antarctica. The establishment and evolution of the present-day fauna was apparently shaped by the unique climate and the geology of the continent. As Australia driftedit was, to some extent, isolated from the effects of global climate change.
Origin[ edit ] New Guinea is a large island located north of Australiaand south-east of Asia. It is part of the Australian Plateknown 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 New Guinea's geological history there have been many land connections with Australia.
These have occurred during Australia s unique flora and fauna 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 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 linethe 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. History of study[ edit ] Influential evolutionary biologist Ernst Mayr came to New Guinea in to make collections for the American Museum of Natural History and banker and naturalist Walter Rothschild.
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. New Guinea contains the largest number of monotreme species of any land mass, with only one species absent: The marsupial fauna of New Guinea is diverse, consisting of the three orders: DasyuromorphiaPeramelemorphia and Diprotodontia.
The native placental mammals are solely represented by the rodents and bats. There are approximately the same number of placental species as marsupials and monotremes. Monotremes and marsupials[ edit ] New Guinea's monotremes are restricted to the family Tachyglossidaealso known as echidnas.
There are four species of echidnas in two genera: 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  and fossils have been found in Australia.
The largest is the bronze quoll Dasyurus spartacusa rare quollfirst discovered in southern New Guinea in Fossils of larger marsupials have been found, including the carnivorous thylacine Thylacinus sp. Those closely related to the Australian kangaroos, such as the agile wallaby Macropus agilisinhabit the open grasslands of New Guinea.
However, the tree-kangarooswhich 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 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 rufonigerare black, orange and yellow.
Many small, herbivorous possum species are native to New Guinea. These include the families: AcrobatidaeBurramyidaePetauridae and Pseudocheiridae. The sugar glider Petaurus breviceps is one of only two New Guinea possums that are able to glide. It has large flaps of skin between its legs, which it spreads whilst in the air.Information about Australia's natural environment can be discovered on rutadeltambor.com Jump to navigation Skip to its forms, flora and fauna.
Today, the identity of all Australians is shaped by a relationship with the natural environment.
and 89 per cent of inshore, freshwater fish are unique to Australia. Australia is richly endowed. A unique feature of Australia's fauna is the relative scarcity of native placental mammals. Consequently, the marsupials — a group of mammals that raise their young in a pouch, including the macropods, possums and dasyuromorphs — occupy many of the ecological niches placental animals occupy elsewhere in the world.
Marsupials were saved from competition with more highly developed mammals. Birds unique to Australia also survived, and distinctive trees and plants developed.
"The South Australian Naturalist" The South Australian Naturalist is our half-yearly journal. Its aims are to promote the study of, and interest in, natural history, and to promote the establishment of reserves for the preservation of our native flora and fauna.
Endangered species (flora/fauna) The flora of Australia comprises a vast assemblage of plant species estimated to over 20, vascular and 14, non-vascular plants, Protected areas have been created in every state and territory to protect and preserve the country's unique ecosystems.
Australia's Unique Flora and Fauna Essay Australia’s unique flora and fauna Australia has over 1 million different native species. Australia’s unique variety of plants and wildlife has evolved as a result of our countries unique conditions.