BOB HIRSHON (host):
Extinction Down Under. I’m Bob Hirshon and this is Science Update.
Imagine a land filled with giant kangaroos and elephant-sized wombats. These were among the oversized animals that roamed Australia during the Pleistocene era. But they went extinct by about 40,000 years ago. Now, research suggests that they were driven to extinction by human hunters, who arrived in Australia by boat just several thousand years earlier. University of Tasmania ecologist Christopher Johnson says the creatures were mostly plant eaters, and their extinction led to a period of massive fires.
CHRISTOPHER JOHNSON (University of Tasmania):
While the big animals were there, a lot of plant material was being eaten, but with the extinction of those big herbivores, fuel was allowed to build up, so the environment became much more prone to fire.
He says hunting probably caused the extinction of North America’s largest animals as well, around 10,000 years ago. And this extinction was also followed by a period of increased wildfires. I’m Bob Hirshon, for AAAS, the science society.