To target threats to the survival of its fauna, Australia has passed wide-ranging federal and state legislation and established numerous protected areas. Unsustainable land use still threatens the survival of many species. These figures exclude dubious taxa like the Roper River scrub robin ( Drymodes superciliaris colcloughi) and possibly extinct taxa like the Christmas Island shrew ( Crocidura trichura). Based on the list of Australian animals extinct in the Holocene, about 33 mammals (27 from the mainland, including the thylacine), 24 birds (three from the mainland), one reptile, and three frog species or subspecies are strongly believed to have become extinct in Australia during the Holocene epoch. Hunting, the introduction of non-native species, and land-management practices involving the modification or destruction of habitats have led to numerous extinctions. The settlement of Australia by Indigenous Australians between 48,000 and 70,000 years ago and by Europeans from 1788, has significantly affected the fauna. Uniquely, Australia has more venomous than non-venomous species of snakes. ![]() Australia is home to two of the five known extant species of monotremes and has numerous venomous species, which include the platypus, spiders, scorpions, octopus, jellyfish, molluscs, stonefish, and stingrays. 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. A unique feature of Australia's fauna is the relative scarcity of native placental mammals. ![]() This high level of endemism can be attributed to the continent's long geographic isolation, tectonic stability, and the effects of a unique pattern of climate change on the soil and flora over geological time. The fauna of Australia consists of a huge variety of animals some 46% of birds, 69% of mammals, 94% of amphibians, and 93% of reptiles that inhabit the continent are endemic to it. They are mildly venomous snakes, but their tiny, fixed rear fangs make them harmless to humans.The red kangaroo is the largest extant macropod and is one of Australia's heraldic animals, appearing with the emu on the coat of arms of Australia. Their diets are variable depending on their range, but they are known to eat rodents, lizards, frogs, birds, and bats. The smallest species reach about 2 feet in length and the largest grow to 4 feet. Knowledge of their behavior in the wild is limited, but they are thought to be highly arboreal, rarely descending from the canopy. There are five recognized species of flying snake, found from western India to the Indonesian archipelago. Scientists don’t know how often or exactly why flying snakes fly, but it’s likely they use their aerobatics to escape predators, to move from tree to tree without having to descend to the forest floor, and possibly even to hunt prey. Flying snakes are technically better gliders than their more popular mammalian equivalents, the flying squirrels. By undulating back and forth, the snake can actually make turns. It propels itself from the branch with the lower half of its body, forms quickly into an S, and flattens to about twice its normal width, giving its normally round body a concave C shape, which can trap air. To prepare for take-off, a flying snake will slither to the end of a branch, and dangle in a J shape. Once thought to be more parachuters than gliders, recent scientific studies have revealed intricate details about how these limbless, tube-shaped creatures turn plummeting into piloting. They’re gliders, using the speed of free fall and contortions of their bodies to catch the air and generate lift. ![]() In the Airįlying snake is a misnomer, since, barring a strong updraft, these animals can’t actually gain altitude. The image of airborne snakes may seem like the stuff of nightmares (or a certain Hollywood movie), but in the jungles of South and Southeast Asia it is reality.
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