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'Australian megafauna' is a term used to describe a number of comparatively large animal species in Australia. These species became extinct during the Pleistocene (20,000-50,000 years before present), but exact dates for their extinction have been lacking until recently.
The cause of the extinction is an active and contentious field of research. It is hypothesised that with the arrival of humans (around 48,000-60,000 years ago), hunting and the use of fire to manage their environment may have contributed to the extinction of the megafauna.^[1] Increased aridity during peak glaciation (about 18,000 years ago) may have also contributed to the extinction of the megafauna. Some proponents claim climate change alone caused extinction of the megafauna, but these arguments have to account for the fact that megaufaunal species comfortably survived two million years of climatic oscillations, including a number of arid glacial periods, before their sudden extinction.
New evidence based on accurate optical luminescence and Uranium-thorium dating of megafaunal remains suggests that humans were the ultimate cause of the extinction of megafauna in Australia.^[2] The dates derived show that all forms of megafauna became extinct in the same rapid timeframe — approximately 47,000 years ago — the period of time in which humans first arrived in Australia. The dates derived suggest the main mechanism for extinction was human burning of a then much less fire-adapted landscape; analysis of oxygen and carbon isotopes from teeth of megafauna indicate sudden, drastic, non-climate-related changes in vegetation and the diet of surviving marsupial species, as well as the loss of megafaunal species. Further analysis of oxygen and carbon isotopes from teeth of megafauna indicate the arid regional climates at the time of extinction were similar to arid regional climates of today, and that the megafauna were well adapted to arid climates.

Contents

Living Australian megafauna

Mammals

Birds

Reptiles

Extinct Australian megafauna: pre-1788

Mammals

Birds

Reptiles

References

External links

Living Australian megafauna

Mammals

★ ''Red Kangaroo'' (''Marcopus rufus'') This species is a very large kangaroo with short, red-brown fur, fading to pale buff below and on the limbs. It has long, pointed earlobes and a squared-off muzzle. Females are smaller than males and are blue-grey with a brown tinge, pale grey below, although arid zone females are coloured more like males. It has two appendages with small claws (much like arms), two muscular legs, which are used for jumping, and a tail, which is often used like a third leg for balance.
Red Kangaroo's legs work much like a rubber band. The male Red Kangaroo can leap in full force approximately 30 feet (9.14 meters) in one leap.
Males grows up to 1.8m (6ft) tall and weigh up to 85 kg (187lbs). Females grow up to 1.1m (3.6ft) tall and weigh up to 35kg (77lbs). Tails can be up to 1m (3ft) along.

★ ''Eastern Grey Kangaroo'' (''Macropus giganteus'') is a marsupial found in southern and eastern Australia, with a population of several million. Although a big Eastern Grey male typically weighs around 66 kg (145 lb.) and stands almost 2 m (6 ft.) tall, the scientific name, ''Macropus giganteus'' (gigantic large-foot), is misleading, as the Red Kangaroo of the semi-arid inland is larger.

★ ''Antilopine Kangaroo'' (''Macropus antilopinus''), sometimes called the 'Antilopine Wallaroo' or the 'Antilopine Wallaby', is a species of macropod found in northern Australia: in Cape York Peninsula in Queensland, the Top End of the Northern Territory, and the Kimberley region of Western Australia. It is a locally common, gregarious grazer. A Field Guide to the Mammals of Australia, , Peter, Menkhorst, Oxford University Press, 2001,

★ ''Wombat'' (''Vombuts ursinus''), are Australian marsupials; they are short-legged, muscular quadrupeds, approximately one metre (3 feet) in length with a very short tail. The name wombat comes from the Eora Aboriginal community who were the original inhabitants of the Sydney area. Wombats dig extensive burrow systems with rodent-like front teeth and powerful claws. Although mainly crepuscular and nocturnal, wombats will also venture out to feed on cool or overcast days. They are not as commonly seen as many animals, but leave ample evidence of their passage, treating fences as a minor inconvenience to be gone through or under and leaving distinctive cubic scats. Wombats are herbivores, their diet consisting mostly of grasses, sedges, herbs, bark and roots. They are preyed on by the Tasmanian Devil. Their fur colour can vary from a sandy colour to brown, or from grey to black.

Birds

★ ''Emu'' The emu was first described under the name of the New Holland Cassowary in Arthur Phillip's Voyage to Botany Bay, published in 1789.[4] The species was named by ornithologist John Latham, who collaborated on Phillip's book and provided the first descriptions of and names for many Australian bird species; its name is Latin for "fast-footed New Hollander". The etymology of the common name Emu is uncertain, but is thought to have come from an Arabic word for large bird that was later used by Portuguese explorers to describe the related Cassowary in New Guinea.[5] In Victoria, some terms for the emu were Barrimal in the Djadja wurrung language, myoure in Gunai, and courn in Jardwadjali.[6]
In his original 1816 description of the emu, Vieillot used two generic names; first Dromiceius, then Dromaius a few pages later. It has been a point of contention ever since which is correct; the latter is more correctly formed, but the convention in taxonomy is that the first name given stands, unless it is clearly a typographical error.[7] Most modern publications, including those of the Australian government,[8] use Dromaius, with Dromiceius mentioned as an alternative spelling.

★ ''Cassowary'' The Northern and Dwarf Cassowaries are not well known. All cassowaries are usually shy, secretive birds of the deep forest, adept at disappearing long before a human knows they are there. Even the more accessible Southern Cassowary of the far north Queensland rain forests is not well understood.
The Southern Cassowary is the largest bird in Australia and the second largest remaining bird in the world (after the ostrich).
Adult Southern Cassowaries are 1.5 to 1.8 m (5 to 6 feet) tall, although some may reach 2 m (6 feet 8 inches), and weigh about 60 kilograms (130 pounds). Females are bigger and more brightly coloured.

Reptiles

★ ''Goanna''
Being predatory lizards, goannas are often quite large, or at least bulky, with sharp teeth and claws. The largest is the Perentie (''Varanus giganteus''), which can grow over 2m in length. They prey on all manner of small animals; insects, lizards, snakes, mammals, birds, eggs. Meals are often eaten whole, and thus the size of their meals depends on the size of the animal itself. However, the Perentie has been observed killing a young kangaroo, and then biting out chunks of flesh like a dog. Goannas have even been blamed for the death of sheep by farmers, though most likely erroneously, as goannas are also eaters of carrion and are attracted to rotting meat.
Not all goannas are gargantuan. Pygmy goannas may be smaller than a man's arm. The smallest of these, the short-tailed monitor (''Varanus brevicuda'') reaches only 20 cm in length. They survive on smaller prey such as insects and mice.

★ ''Carpet Python''
There are many further species in the carpet python complex, including the ochre-red Bredl's or Centralian python (''Morelia bredli''). This python, which is native to a small area around the MacDonnell Ranges and the town of Alice Springs in Australia's Northern Territory, is a unique member of the complex, having many more smaller scales, so that the body more closely resembles a skin. In captivity, striped, spotted and hypomelanistic specimens have been observed. Bredl's python is a medium sized carpet python, averaging around 5 feet, however it is noted for its thicker girth. Adults can breed at a later age than most carpet pythons.

★ ''Saltwater Crocodile''
A healthy adult male saltwater crocodile is typically 4.8 to 7 metres (15.75 to 21.6 ft) long, and weighs up to 770 kg (1697 lb), with many exceptions being much larger than this. Many large sizes have been reported[1][2], [1] Females are much smaller than males, with typical female body lengths in the range of 2.5–3 meters. A 28 foot (8.5 meters) individual was reportedly shot on the Norman River of Queensland in 1957 and a cast was made of this animal (which can be viewed and is quite the popular tourist attraction), but due to the time since the occurrence and lack of rock hard evidence (other than the plaster) it is not considered "official". The saltwater crocodile has fewer armor plates on its neck than other crocodilians, and its broad body contrasts with most other lean crocodiles, leading to early unverified assumptions the reptile was an alligator.[2]Crocodylus porosus (Schneider, 1801), by Adam Britton from the Crocodilian Species List.

Extinct Australian megafauna: pre-1788

The following is an incomplete list of Australian megafauna, in the format:

★ ''Latin name'', (common name, period alive), and a brief description.

Mammals

★ ''Procoptodon goliath'' (the Giant Short-faced Kangaroo) is the largest kangaroo to have ever lived. It grew 2-3 metres (7-10 feet) tall, and weighed up to 230 kilograms. It had a flat shortened face with jaw and teeth adapted for chewing tough semi-arid vegetation, and forward-looking eyes providing stereoscopic vision. Procoptodon was one of seventeen species in three genera in the Sthenurine subfamily, all of which are extinct. Sthenurines inhabited open woodlands in central Northern Australia as the tropical rainforests were beginning to retreat. All sthenurines had an extremely developed, almost hoof-like, fourth toe on the hindlimbs, with other toes vestigial. Additionally, elastic ligaments between the toe bones gave this group improved spring and speed compared to modern kangaroos. Sthenurine forelimbs were long with two extra-long fingers and claws compared with the relatively small, stiff arms of modern macropods. These may have been used for pulling branches nearer for eating and for quadrupedal movement for short distances.

★ ''Simosthenurus occidentalis'' (another Sthenurine) was about as tall as a modern Eastern Grey Kangaroo, but much more robust. It is one of the nine species of leaf-eating kangaroos identified in fossils found in the Naracoorte Caves National Park.

★ ''Diprotodon optatum'' was the largest species of Diprotodontid. Approximately three metres long, two metres high at the shoulder and weighing up to two tonnes, it resembled a giant wombat. It is the largest marsupial currently known.

★ ''Zygomaturus trilobus'' was a smaller (bullock-sized, about two metres long by one metre high) Diprotodontid that may have had a short trunk. It appears to have lived in wetlands, using two fork-like incisors to shovel up reeds and sedges for food.

★ ''Palorchestes azael'' (the Marsupial Tapir) was a Diprotodontid of a similar size to ''Zygomaturus'', with long claws and a longish trunk. It lived in the Miocene.

★ ''Phascolarctos stirtoni'' was a koala similar to the modern form, but one third larger.

★ ''Thylacoleo carnifex'', (the Marsupial Lion), was the size of a leopard, and had a cat-like skull with large slicing pre-molars. It had a retractable thumb-claw and massive forelimbs. It was almost certainly carnivorous and a tree-dweller.

★ ''Sarcophilus harrisii laniarius'' was a large form of the Tasmanian Devil.

★ ''Zaglossus hacketti'' was a sheep-sized echidna uncovered in Mammoth Cave in Western Australia, and is the largest monotreme so far uncovered.

★ ''Megalibgwilia ramsayi'' was a large, long-beaked echidna with powerful forelimbs for digging. Its diet would probably have included worms and grubs rather than ants.

★ ''Propleopus oscillans'' (the Carnivorous Kangaroo), from the Miocene and Pliocene epochs, was a large (~70 kilogram) rat-kangaroo with large shearing and stout grinding teeth that indicate it may have been an opportunistic carnivore able to eat insects, vertebrates (possibly carrion), fruits, and soft leaves.

★ ''Protemnodon'' a form of giant wallaby with 4 species.^[3]

★ ''Congruus congruus'' a wallaby from Naracoorte.

★ ''Warrendja wakefieldi a wombat from Naracoorte.

Birds

★ Family Dromornithidae: this group of birds was more closely related to waterfowl than modern ratites.

★
★ ''Dromornis stirtoni'', (Stirton's Thunder Bird, Miocene epoch) was a flightless bird three metres tall that weighed about 500 kilograms. It is one of the largest birds so far discovered. It inhabited subtropical open woodlands and may have been carnivorous. It was heavier than the Moa and taller than the Aepyornis.

★
★ ''Bullockornis planei'' (the 'Demon Duck of Doom') was another huge member of the Dromornithidae. It was up to 2.5 metres tall and weighed up to 250 kilograms, and was probably carnivorous.

★
★ ''Genyornis newtoni'' (the Mihirung) was related to ''Dromornis'', and was about the height of an ostrich. It was the last survivor of the Dromornithidae. It had a large lower jaw and was probably omnivorous.

★ ''Leipoa gallinacea'' (formerly ''Progura'') was a giant malleefowl.

Reptiles

★ ''Megalania prisca'' was a giant, carnivorous goanna-like lizard that might have grown to as long as seven metres, and weighed up to 1,940 kilograms (Molnar, 2004).

★ ''Wonambi naracoortensis'' was a non-venomous snake of five to six metres in length, an ambush predator at waterholes which killed its prey by constriction.

★ ''Quinkana'' sp., was a terrestrial crocodile which grew from five to possibly 7 metres in length. It had long legs positioned underneath its body, and chased down mammals, birds and other reptiles for food. Its teeth were blade-like for cutting rather than pointed for gripping as with water dwelling crocodiles. It belonged to the Mekosuchine subfamily (all now extinct). It was discovered at Bluff Downs in Queensland.

★ ''Liasis'' sp., (Bluff Downs Giant Python), lived during the Pliocene epoch, grew up to ten metres long, and is the largest Australian snake known. It hunted mammals, birds and reptiles in riparian woodlands. It is most similar to the extant Olive Python (''Liasis olivacea'').^[4]

References

1. Miller, G. H. 2005. Ecosystem Collapse in Pleistocene Australia and a Human Role in Megafaunal Extinction. ''Science'', 309:287-290 PMID 16002615
2. Prideaux, G.J. et al. 2007. An arid-adapted middle Pleistocene vertebrate fauna from south-central Australia. ''Nature'' 445:422-425
3. Helgen, K.M., Wells, R.T., Kear, B.P., Gerdtz, W.R., and Flannery, T.F. (2006). Ecological and evolutionary significance of sizes of giant extinct kangaroos. ''Australian Journal of Zoology'' 54, 293–303. doi:10.1071/ZO05077
4. Scanlon JD and Mackness BS. 2001. A new giant python from the Pliocene Bluff Downs Local Fauna of northeastern Queensland. ''Alcheringa'' 25: 425-437


★ Field, J. H. and J. Dodson. 1999. Late Pleistocene megafauna and archaeology from Cuddie Springs, south-eastern Australia. ''Proceedings of the Prehistoric Society'' 65: 1-27.

★ Field, J. H. and W. E. Boles. 1998. ''Genyornis newtoni'' and ''Dromaius novaehollandiae'' at 30,000 b.p. in central northern New South Wales. ''Alcheringa'' 22: 177-188.

★ Long, J.A., Archer, M. Flannery, T.F. & Hand, S. 2003. Prehistoric Mammals of Australia and New Guinea -100 Million Years of Evolution. Johns Hopkins University Press, Baltimore. 242pp.

★ Molnar, R. 2004. Dragons in the Dust: The Paleobiology of the Giant Lizard Megalania. Indiana University Press. Page: 127.

★ Murray, P. F. and D. Megirian. 1998. The skull of dromornithid birds: anatomical evidence for their relationship to Anseriformes (Dromornithidae, Anseriformes). ''Records of the South Australian Museum'' 31: 51-97.

★ Roberts, R. G., T. F. Flannery, L. A. Ayliffe, H. Yoshida, J. M. Olley, G. J. Prideaux, G. M. Laslett, A. Baynes, M. A. Smith, R. Jones, and B. L. Smith. 2001. ''New ages for the last Australian megafauna: continent-wide extinction about 46,000 years ago.'' Science 292: 1888-1892.

★ Wroe, S., J. Field, and R. Fullagar. 2002. ''Lost giants.'' Nature Australia 27(5): 54-61.

External links

★ Cuddie Springs

★ Interview with Dr John Long, curator at the Museum of Victoria

★ Naracoorte caves in South Australia

★ Lost Kingdoms