THERE HAS BEEN a great deal of environmental change in the Australian region over the 50,000 years that people have lived here. There is going to be a lot more of it in the future, too, whether or not the specifics of current climate-change models are borne out.

About 120,000 years ago, temperatures and sea levels were like today’s but then began falling. By the time people first settled the continent 50,000 years ago, sea levels were perhaps thirty metres lower than now, the climate was mild and wet and many now-dry inland lakes were full. The lower parts of the Murray-Darling system provided a particularly rich environment for people. This has been revealed in stunning detail by archaeological research at Lake Mungo in south-western NSW. These days, Mungo is a flat, parched expanse of low scrub edged by the thirty-metre high, thirty-kilometre long and mightily impressive Walls of China sand dune. When the lake was full, there was an abundance of clear water, freshwater fish including Murray Cod, mussels and crustaceans. Emu and a wide variety of marsupials including the “Tasmanian” tiger also flocked to the water. Waterfowl probably did, too, although their bones have not survived. The remains of all the other creatures, as well as more enduring parts of the tools and weapons used to hunt and process them, have been found in ancient shell middens and campfires in the great sand dune, indicating the extensive use people made of the lake and its surrounds tens of millennia ago.[i]