At www.nature.com/news/first-australians-may-have-been-migrants-rather-than… .. we have news of a paper in the Proceedings of the Royal Society B (doi:10.1038/nature.2013.12865) that has used C14 methodology to seek a better understanding of the peopling of Australia. Computer simulation of various strands of evidence have been put into the mincing machine and it is now claimed some 1000 people made landfall around 50,000 years ago, numbers that are thought to indicate intentional migration rather than accidental stranding of a few people washed up on the coast. Importantly, the study has found evidence the population was devastated during the last Ice Age and later managed to rebuild their numbers in the Holocene.
A lot of assumptions have been made as the population curve is contrived, an artifact of the methodology rather than a fact. The population crash around 20,000 years ago is especially problematical – during the Late Glacial Maximum. This hardly affected Australia apart from the extreme SE corner so why didn't people simply move north? A drop in numbers may have been necessary in order to get the population curve to have a smooth transit from the end of the Ice Age to the 19th century. What is of course absent from all of this is catastrophism – and a succession of global or localised events that may have led to population falls, at any point between 50,000 years ago and the present.