CANBERRA, AUSTRALIA—Occupation patterns in prehistoric Australia are closely linked to climate trends, according to a study conducted by Alan Williams of Australia National University and Peter Veth of the University of Western Australia. They used radiocarbon dates from more than 1,000 prehistoric campfire sites to track Australia’s ancient population levels. “Demographic models suggest populations may have been quite high before the last ice age,” Veth told Science Network: Western Australia. They then compared these results with the climate change profiles from a recent study of Australia’s palaeoclimate conducted by the OZ-INTIMATE (Australasian INTegration of Ice core, Marine, and TErrestrial records) Project. They found that the population remained steady or perhaps even declined from 25,000 years ago, during the Last Glacial Maximum, when temperatures were about ten degrees cooler. “Then with the restructure in population and possibly lower carrying capacity for large portions of the continent that became more arid, population levels of demography may actually have become more negative,” he explained. When the wet season returned in the north some 13,000 years ago, campfire numbers began to grow again. For more on prehistoric Australia, go to "The Rock Art of Malarrak."