There are two central mysteries about human history in Australia. First, when did people arrive on the world's southernmost inhabitable continent? And second, how did they colonize it? A paper in Nature offers new answers, based on an extensive analysis of decades-old DNA.
By studying the mitochondrial DNA of Aboriginal Australians from all across the continent, University of Adelaide biologist Alan Cooper and his team were able to trace the population back to its most recent common ancestor, a woman who lived between 43,000 and 47,000 years ago. Because mitochondrial DNA is passed from mothers to children virtually unchanged, it's often used to trace genetic histories over long time spans. Based on this finding and dates of the earliest archaeological sites in Australia, Cooper and colleagues write that the continent was likely colonized by a single group of people about 50,000 years ago.
from Australia was colonized by a single group 50,000 years ago