Washington, August 12 : A new research, by UK and Australian scientists, has suggested that the mass extinction of Tasmania's large prehistoric animals was the result of human hunting, and not climate change as previously believed.
Scientists have long argued over the reasons behind the worldwide mass extinctions that took place towards the end of the last ice age.
The main culprits are generally thought to be climate change or some form of human impact. People only arrived in Tasmania around 43,000 years ago, when the island became temporarily connected by a land bridge to mainland Australia.
None of Tasmania's giant animals, known as 'megafauna' were known to have survived until this time.
This appeared to clear humans of any involvement in the disappearance of the island's large megafauna.
But, the new international research reports the discovery of giant kangaroos, marsupial 'rhinos' and 'leopards' surviving in Tasmania until people arrived, placing humans back on the list of likely culprits for the subsequent extinction of the megafauna.
Using the latest radiocarbon and luminescence dating techniques, the team was able to determine the age of the fossilised remains of the megafauna more accurately than ever before.
The results showed that some of these animals survived until at least 41,000 years ago-much later than previously thought and up to 2,000 years after the first human settlers arrived.
As climate in Tasmania was not changing dramatically at this time, the researchers argue that this is evidence of these species being driven to extinction through over-hunting by humans.
According to Professor Chris Turney of the University of Exeter, lead author of the research paper, ever since Charles Darwin's discovery of giant ground sloth remains in South America, debate has ensued about the cause of early extinction of the world's megafauna.
"Now, 150 years on from the publication of Darwin's seminal work "The Origin of Species", the argument for climate change being the cause of this mass extinction has been seriously undermined," he said.
"It is sad to know that our ancestors played such a major role in the extinction of these species - and sadder still when we consider that this trend continues today," he added.
Previous research has shown that 90 per cent of mainland Australia's megafauna disappeared about 46,000 years ago, soon after humans first settled the continent.
But humans did not reach Tasmania until a few thousand years later, when the island became connected to the mainland by a land bridge as sea levels fell during the last glaciation.
According to Professor Bert Roberts of the University of Wollongong, Australia, "The Tasmanian results echo those on mainland Australia, putting humans squarely back in the frame as the driving force behind megafaunal extinction."