Megalania - Australia's lizard king

http://en.wikipedia.org/wiki/Megalania

Megalania (Megalania prisca or Varanus priscus) was a very large goanna or monitor lizard, now extinct. It was part of a megafaunal assemblage that inhabited southern Australia during the Pleistocene.

Megalania is believed to have disappeared around 40,000 years ago, but not before the first Aboriginal settlers of Australia may have encountered them.

Wikipedia recently uploaded some interesting images of Megalania, which we're sharing with you this week.

http://en.wikipedia.org/wiki/Megalania

http://en.wikipedia.org/wiki/Megalania

http://en.wikipedia.org/wiki/Megalania

Is Megalania still roaming the Australian outback? Some Australians think so...

Humans behind megafauna extinction - not climate change

Humans wiped out Australia's megafauna, according to a new study published in the journal Science.

Hunting was behind the demise of the giant diprotodons, towering kangaroos, marsupial lions and birds twice the size of emus, and not climate change.

One of the report's authors Prof Barry Brook said "Debate about the possible cause of these late Pleistocene extinctions has continued for more than 150 years, with scientists divided over whether climate change or the arrival of humans has been responsible for their demise...Australia was colonised during a time when the climate was relatively benign, supporting the view that people, not climate change, caused the extinctions here."

But one site in western NSW - Cuddie Springs - stood out as an anomaly. Fossils of super-sized kangaroos, giant birds and the rhino-sized Diprotodon (the largest marsupial ever to roam Australia) were found in the same sedimentary layers as stone tools, leading some scientists to previously claim "unequivocal evidence" of a long overlap of humans and megafauna.

However, Professor Roberts - the lead author of the Science paper "And Then There Were None?" - says direct dating of fossils shows that the artefacts and megafauna fossils at the Cuddie Springs site were mixed together over many thousands of years, long after the giant animals had died.

"These results provide no evidence for the late survival of megafauna at this site," Professor Roberts says.

"Given that people arrived in Australia between 60,000 and 45,000 years ago, human impact was the likely extinction driver, either through hunting or habitat disturbance," he says.

Professor Brook says previous claims for sites containing younger megafauna - such as in Kangaroo Island, eastern Victoria and the highlands of Papua New Guinea - should also be considered suspect in the light of these revised, older dates for the Cuddie Springs fossils.

Fossil hoard uncovered in WA

A treasure trove of fossils up to a million years old has been found in three caves under the Nullarbor.

Palaeontologists returned last month from their fifth expedition to Last Tree Cave, Flightstar and Leaena's Breath, on the WA side of the Nullarbor Plain, where about 100,000 bones were collected during the past two field trips.

Flinders University palaeontologist Gavin Prideaux said the caves, discovered in 2002, were littered with fossils.

"There were a lot of complete skeletons of megafauna species just sort of lying on the cave floors," he said.

One of the most impressive finds was an almost complete skeleton of a Thylacoleo carnifex, or marsupial lion - a prehistoric animal that was the size of a leopard, built like a bear and able to stand up like a kangaroo. It had huge claws and the most powerful bite of any known mammal.

WA Museum documentary director Clay Bryce, who has been involved in the project since its inception, described the caves as a treasure trove of extraordinary fossil material.

"From one skeleton we suddenly went to 11 Thylacoleo skeletons, tree kangaroos, koalas, Thylacines, giant wombats, untold numbers of birds, giant kangaroos, Procoptodons, smaller species of kangaroo, horned wallabies, the list goes on and on," he said.

Dr Prideaux said the caves had acted as an animal trap, catching animals that fell through the entrance and birds that could not find their way out.

On the most recent expedition researchers rescued two live birds that had become disoriented in the caves.

Dr Prideaux said at least eight confirmed new species had been found in the caves and that was likely to rise to 15 to 20 new species as more bones were analysed.

The research was part-funded by National Geographic.

Megalania puts in appearance at Vic exhibition

A skeleton of prehistoric reptile Megalania was on display at the recent Sci-Spy! event held at Monash University Gippsland to celebrate National Science Week in the region.

Megalania was a six-metre long lizard similar to the komodo dragon which roamed central Australia about 40,000 years ago, which scientists believed claimed victims as an ambush predator.

Monash Science Centre scientist Dr Corrie Williams described Megalania as “big, impressive and heavy” and said the lizard had a tendency to provoke a response in children.

In addition to Megalania, the skeleton of the prehistoric bird Bullockornis will also be on display, which was about 2.5 metres tall and weighed about 500 kilograms.

Jurassic park in a suburban Sydney garden

Trespassers beware! Spiteri’s Ambarvale residence is guarded by Jurassic era dinosaurs. 

The south-western Sydney self-taught paleo artist has been crafting dinosaurs and exhibiting them in his front yard for the past 10 years. His latest artworks - Jurassic king allosaurus and venomous dilophosaurus - have been a magnet during the school holidays.

While a lack of room has temporarily put a halt on more dinosaurs, Mr Spiteri has lodged a proposal with Campbelltown library to have prehistoric creatures placed on show from the ancient Indigenous period that include the prehistoric lizard, megalania.

Humans tipped megafauna over the edge

THE arrival of humans was probably decisive in the extinction of megafauna living in the South West 40,000 years ago, though climate change and fire may have contributed, according to new research.

Fossils of animals ranging from tiny 30g native mice to giant 500kg marsupials called diprotodontids have been recorded in a cave in the Leeuwin-Naturaliste region.

The cave sediments contain the richest fossil fauna from the western two-thirds of the Australian continent, and provide the best record available of how 90 per cent of the larger mammal species became extinct shortly after the first humans arrived.

Published recently in the Proceedings of the National Academy of Sciences of the United States of America, the findings suggest that one-factor explanations for the extinctions are over-simplistic.

The research team included researchers from the Universities of WA, Wollongong, Melbourne, Flinders and Australian National universities, as well as a scientist working with the Augusta-Margaret River Tourism Association.

They sampled fossils from Tight Entrance Cave and found that within 10 millennia of human arrival, all larger animals except the grey kangaroo and thylacine became extinct. Read more here.