Humans wiped out giant kangaroo

New evidence shows for the first time that giant kangaroos and the marsupial equivalent of rhinos and leopards still populated Tasmania when humans first arrived on the island 43,000 years ago.

Today none of the animals survive. Since the climate was not changing dramatically at the time, scientists have concluded that the creatures were driven into extinction by over-zealous hunting.

Australia's megafauna had by this period in history already disappeared, following the arrival of humans.

Experts have debated whether the mass extinction was due to natural effects, such as climate, or human activity.

The fact that Tasmania's large animals only vanished after the first humans travelled to the island provides strong support for the latter theory.

Previously it was thought the Tasmanian megafauna was already gone by the time humans crossed the land bridge which then temporarily joined the island with mainland Australia.

This would have cleared humans of any involvement in the animals' disappearance. But new fossil dating techniques have now shown that the creatures survived in Tasmania far longer than was previously thought.

Examination of the bones revealed that some animals were living in Tasmania as recently as 41,000 years ago, 2,000 years after the arrival of the first human settlers. The findings provide a clue to the fate of extinct large prehistoric animals not only in Tasmania and Australia, but around the world.

Professor Chris Turney, from the University of Exeter, who led the research, said: "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. 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."