An international team has found fossils of plants and animals in the mountains on the interior of Antarctica, which it believes became extinct due to an abrupt climate cooling of 8 degree Celsius in 200,000 years.In their study, the scientists have combined evidence from glaciers from the preserved ecology, volcanic ashes and modelling to reveal the full extent of the big freeze in part of the southernmost continent called the Dry Valleys.
According to them, the lost world is an extremely rare find in the continent, one that also provides an insight into what could be there in a century or two as the planet warms, 'The Daily Telegraph' reported.
Lead researcher Professor Adam Lewis of North Dakota State University said, "The discovery of lake deposits with perfectly preserved fossils of mosses, diatoms and minute crustacea called ostracods is particularly exciting.
"They are the first to be found even though scientific expeditions have been visiting the Dry Valleys since they were discovered during the first Scott expedition in 1902-1903."
"The fossil finds allow us to examine Antarctica as it existed just prior to climate cooling at 13.9 million years ago. It is a unique window into the past. To study deposits is akin to strolling across the Dry Valleys 14.1 million years ago," said co-researcher David Marchant of Boston University.
However, what caused the big freeze is yet unknown though theories abound and include phenomena as different as the levels of carbon dioxide in the atmosphere and tectonic shifts that affected ocean circulation.
"If we can understand how we got into this relatively cold climate phase, then that can help predict how global warming might push us back out of this phase.
"For the vast majority of Earth history there was no permanent ice like is common today at poles and even the tropics at high elevation," Prof Lewis was quoted by the
British newspaper as saying.
The findings have been published in the 'Proceedings of the National Academy of Sciences' journal.
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