<p> Humans, not climate change, wiped out Ice Age megafauna -- giant marsupials, huge reptiles, and flightless birds -- 40,000 years ago, a new study has claimed.<br /><br /></p>.<p>For decades, researchers have been debating the reasons behind these enigmatic Ice Age mass extinctions.<br /><br />Now, Australian scientists have concluded that human hunting caused the extinction of the ancient giant animals -- or megafauna -- that roamed the continent and vanished about 40,000 years ago.<br /><br />Their study blames humans rather than climate change for the demise of the massive plant-eating animals such as 300 -kilogramme kangaroos, birds that were twice the size of emus and a leopard-sized marsupial lion.<br /><br />"The debate really should be over now. Hunting did it, end of story," 'The Daily Telegraph' quoted lead scientist John Alroy at Sydney's Macquarie University as saying.<br /><br />The scientists claim to have solved the mystery by studying fungi found in the dung of large herbivores. Thy examined two cores of sediment from a fossilized swamp in Queensland dating back 130,000 years.<br /><br />"When there was lots of fungus, there was lots of dung and lots of big animals making it. When they disappeared, their dung fungus went too," said Professor Chris Johnson, from the University of Tasmania, another scientist.<br /><br />The scientists found that megafauna numbers were stable until 40,000 years ago despite two periods of climate change. They conclude that the newly arrived humans hunted the animals to extinction and that the reduced grazing caused an increase in fuel loads and the intensity of fires.<br /><br />They argue that newly arrived humans hunted the animals to extinction, with the reduced grazing pressure causing an increase in the fuel load and fire intensity. This prompted the disappearance of rainforests and the expansion of eucalypt-dominated forests.<br /><br />However, some experts are not convinced. "The only evidence we have from Queensland for megafauna indicates that they were gone before humans arrived," Judith Field of the University of New South Wales, said.</p>
<p> Humans, not climate change, wiped out Ice Age megafauna -- giant marsupials, huge reptiles, and flightless birds -- 40,000 years ago, a new study has claimed.<br /><br /></p>.<p>For decades, researchers have been debating the reasons behind these enigmatic Ice Age mass extinctions.<br /><br />Now, Australian scientists have concluded that human hunting caused the extinction of the ancient giant animals -- or megafauna -- that roamed the continent and vanished about 40,000 years ago.<br /><br />Their study blames humans rather than climate change for the demise of the massive plant-eating animals such as 300 -kilogramme kangaroos, birds that were twice the size of emus and a leopard-sized marsupial lion.<br /><br />"The debate really should be over now. Hunting did it, end of story," 'The Daily Telegraph' quoted lead scientist John Alroy at Sydney's Macquarie University as saying.<br /><br />The scientists claim to have solved the mystery by studying fungi found in the dung of large herbivores. Thy examined two cores of sediment from a fossilized swamp in Queensland dating back 130,000 years.<br /><br />"When there was lots of fungus, there was lots of dung and lots of big animals making it. When they disappeared, their dung fungus went too," said Professor Chris Johnson, from the University of Tasmania, another scientist.<br /><br />The scientists found that megafauna numbers were stable until 40,000 years ago despite two periods of climate change. They conclude that the newly arrived humans hunted the animals to extinction and that the reduced grazing caused an increase in fuel loads and the intensity of fires.<br /><br />They argue that newly arrived humans hunted the animals to extinction, with the reduced grazing pressure causing an increase in the fuel load and fire intensity. This prompted the disappearance of rainforests and the expansion of eucalypt-dominated forests.<br /><br />However, some experts are not convinced. "The only evidence we have from Queensland for megafauna indicates that they were gone before humans arrived," Judith Field of the University of New South Wales, said.</p>