During the ice long time , so much of Australia dried out that scientist have wondered how mintage that need permanent water survived . The discovery North Stradbroke Island ’s wetlands have been a refuge for body of water - loving plants and animals for some 200,000 years provides an solution . The discovery could take one of the biggest missing pieces in the planetary climate platter , revealing how eastern Australia changed over that period . antecedently this had to be extrapolated from elsewhere and a smattering of sites , many of them discontinuous , from the extremity of the continent .
When ice sheets cover much of North America and Eurasia , the oceans retreated with lack water . share of the cosmos that are now snug to the coast were often part of an desiccated interior . The cold conditions also imply less evaporation and therefore rain . Australia , so much of which is dry even today , was specially affected .
Besides the query of how coinage reliant on permanent water hold up , the absence of long - standing wetland has been a challenge for paleoclimatologists . Ice cores provide a phonograph recording of convert conditions in Antarctica and Greenland , and sediments at the bottom of lakes offer something similar for other Continent , but what does one do where neither is available ?
Look harder , it seems , and North Stradbroke Island , near Brisbane , reward the hunting . “ There are more wetlands on North Stradbroke Island dating to the last ice age than anywhere else in Australia , " said the University of Adelaide’sDr John Tibbyin astatement . Tibby is first writer of a newspaper in theJournal of Quaternary Sciencerevealing the old age of the site .
" We core and dated 16 wetlands on the island and find six dating to the Ice Age or earlier , with one being more than 200,000 years honest-to-goodness , " articulate Centennial State - authorDr Jonathan Marshallof the Queensland Department of Science , Information Technology , and Innovation . These cores produced solution well above those at Australia ’s other website .
The fact the wetlands predate human habitation of Australia means the oldest cores may unwrap the influence Indigenous Australians had on the local landscape – something also seen in cores ingest on islands off Tasmaniaannouncedthe same day .
More at once , the find is proving a gem treasure trove for exploring how the local mood has changed . “ We ’re using the chemicals in leaves to limit preceding rainfall , and fossil alga to tell us how the water supply in the wetland has change , " Tibby said . " Using this data , we can glean perceptivity into whether mood changed at the same metre Australian megafauna went nonextant . Previously , efforts to determine the clime at picky points in Australia ’s past bank on measurement taken as far off as Antarctica .
The wetlands ' extraordinary seniority has been attributed to connections to local groundwater , sustaining them through geological period of drouth .
