The earliest Australians
One of the really big challenges in anthropology is to date accurately the arrival of humans in the different continents. New results, to be published in a forthcoming issue of the Journal of Quaternary Science, show that humans arrived in Australia a lot earlier than was previously thought.
It is generally argued that humans evolved in Africa and then spread out over the other continents progressively through time, arriving in the most distant, such as Australasia, relatively recently. The conventional view, based on radiocarbon dating, is that the earliest human colonisation of Australia occurred only around 40,000 years ago. New evidence, published in the Journal of Quaternary Science, pushes the arrival of the first humans in Australia back by as much as 15,000 years, to between 45,000 and 55,000 years ago.
Dr Chris Turney of Queen’s University, Belfast and Australian colleagues report evidence for extensive burning at this time in North Queensland which is independent of any climate change. Using new techniques for radiocarbon dating lake sediments, Dr Turney and his colleagues attribute these extensive fires to human activity.
Interestingly this earlier arrival time is consistent with the timing of the extinction of many very large vertebrates in Australia, which is usually attributed to overkill by humans. As with any biological invasion by top predators, the arrival of humans clearly had a profound impact on the pre-existing vegetation and animals of the continent.
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