http://www.abc.net.au/news/items/200701/1824582.htm?southeastsa
Humans to blame for megafauna extinction: study
Wednesday, 10 January 2007. 15:23 (AEDT)Wednesday, 10 January 2007. 14:23
(ACST)Wednesday, 10 January 2007. 14:23 (AEST)Wednesday, 10 January 2007.
15:23 (ACDT)Wednesday, 10 January 2007. 13:23 (AWDT)
After more than 100 years debate, scientists claim they know why the large
ancient animals known as megafauna became extinct in south-east South
Australia.
A study published in an international journal says humans were the main
factor in the extinction of megafauna around Naracoorte.
Scientists say new evidence from fossils in Naracoorte's world heritage
listed caves has discounted the popular belief that climate change killed
the animals.
Flinders University palaeontologist Dr Gavin Prideaux says his team's
findings will unlock the mystery in a number of areas.
"I guess what we'd like to think we've done with this work is to set a
benchmark for one area where the same sorts of approaches can be made in
other areas to examine the pattern is the same there," he said.
"I think the question is drifting away from whether it was climate change
or humans that killed the megafauna and more that how was it that humans
drove these animals to extinction?"
http://www.dailyindia.com/show/96911.php/Australias-giant-prehistoric-animals-extinction-due-to-humans-not-climate
Australia's giant prehistoric animals' extinction due to humans, not
climate
Sydney, Dec 26 (ANI): A new study by an Australian palaeontologist has
revealed that 90 percent of the continent's so called megafauna -
prehistoric animals such as giant goannas, three metre tall kangaroos and
rhino sized marsupials - died within 20,000 years of human arrival.
The new research, published in international journal Geology's January
2007 edition, is set to fuel what has become one of palaeontology's
longest-running and contentious debates, as till now experts believed
climate change was responsible for wiping out Australia's megafauna.
For his study, Dr Gavin Prideaux, a Western Australian Museum and Flinders
University palaeontologist dated fossils found in the Naracoorte Caves
World Heritage Area in south-eastern South Australia, which contain the
country's richest collection of Pleistocene fossils dating back 1.8
million to 10 thousand years.
He compared the fossil data to a 500 thousand-year record of local
rainfall, which was determined by analysing the caves' stalagmite system,
and additional climate clues found in the sediments.
The fossil evidence revealed 'surprising stability' in the mammal
composition in successive periods of wet and dry. In other words, the
megafauna became extinct during environmental conditions similar to those
under which they thrived.
"Climate change was certainly not the main culprit in the extinctions. Our
data show that the megafauna was resilient to climatic fluctuations over
the past half-million years," the Sydney Morning Herald quoted Dr Prideaux
as saying.
"Although populations fluctuated locally in concert with cyclical climatic
changes, with larger species favoured in wetter times, most if not all of
them survived even the driest times - then humans arrived," he said. (ANI)
