Friday, January 22, 2010

Humans Killed Australian Megafauna

And Then There Were None?. 2010. R. G. Roberts & B. W. Brook. Science 327: 420-422.
New research indicates that humans, not climate change, caused the demise of Australia's megafauna - giant marsupials, huge reptiles and flightless birds - at least 40,000 years ago.

2001: A Space Odyssey © MGM. Art & Story by Jack Kirby © Marvel Comics
Improved dating methods show that humans and megafauna only co-existed for a relatively short time after people inhabited Australia, adding weight to the argument that hunting led to the extinction of large-bodied species.

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.

New methods to directly date bones and teeth of extinct species show that megafauna fossils and Aboriginal tools do not all date from the same period- they were mixed together over many thousands of years, long after the giant animals had died.

"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. link