Ground breaking archaeological research uncovers 49,000 years of undocumented human existence in arid Australia

03 November 2016

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Giles Hamm, Archaeologist

A paper published in Nature, the world’s most cited scientific journal, proves that humans occupied the deserts of northern South Australia and began developing sophisticated tools 10,000 years earlier than previously documented.

Principal author and researcher Giles Hamm’s findings from the Warratyi Rock Shelter show it to contain the oldest evidence of Aboriginal occupation in South Australia. This evidence reveals new insights into modern human colonisation of Australia, unique cultural innovation and interaction with now-extinct megafauna.

Mr Hamm, an Honorary Fellow of the South Australian Museum and La Trobe University PhD candidate, is an arid zone research archaeologist who has worked for the last nine years with the Adnyamathanha people in the Flinders Ranges along with geomorphologist Dr Peter Mitchell, geochronology specialists Dr Lee Arnold and Professor Nigel Spooner from the University of Adelaide, and other researchers from Flinders University and the University of Queensland, to uncover a series of world-firsts in South Australia.

“We excavated a small rock shelter site in the Flinders Ranges in an effort to understand the adaptability of human populations in the Australian arid region as well as causes of megafaunal extinctions 40,000-50,000 years ago,” said Mr Hamm.

“The results of our scientific investigations tell us that people not only settled in the arid interior of Australia within a few millennia of entering the continent, but they also developed milestone technologies much earlier than we have previously thought.

“The Warratyi Rock Shelter in northern Flinders Ranges has by far the earliest-known evidence of the use of ochre pigment in Australia as well as hafting technology in Australia and South-east Asia” Mr Hamm said.

 The advent of hafting, involving joining two elements such as a wooden handle and stone blade, represents a significant development in technology.

“The hafted tools we found date up to 40,000 years in age, which demonstrates the early complexity of Australian Aboriginal people’s knowledge,” said Mr Hamm.

“This is an incredible find as, prior to our research, the oldest artefacts of this kind had been dated at around 9-10 thousand years old,” he said.

In conducting this research Mr Hamm worked closely with the Adnyamathanha people, who played a pivotal role in providing cultural and historical advice, as well as assisting with fieldwork and logistical matters.

Michael Anderson, Chairperson of the Adnyamathanha Traditional Lands Association, said that the Adnyamathanha people are connected to the Northern Flinders Ranges through culture.

“To see scientific evidence confirming our cultural activities over such a long period of time makes us feel proud to be Adnyamathanha. On behalf of the Adnyamathanha Traditional Lands Association I thank Giles and his team for the truly fantastic work they have done,” Mr Anderson said.

The site that the Adnyamathanha people helped excavate also contained bone tools and backed artefacts that date up to 10,000 years older than any others so far found in Australia or South-east Asia. Other items unearthed at the site have been scientifically proven to demonstrate the earliest known use of ochre, dating up to 49,000 years ago. In addition, the excavated sample held the first archaeological evidence for the use of gypsum as a pigment, dating to 33,000-40,000 years ago.

Evidence from this site, combined with learning from the knowledge of the traditional owners of the Flinders Ranges, revealed that a dynamic, adaptive Aboriginal culture existed in arid Australia within only a few thousand years of the continent’s settlement. Aboriginal people may have used Warratyi as a refuge when the surrounding country was too arid to exploit, and as a temporary campsite when environmental conditions became more stable.

“Sites like this are incredibly rare – this is the only site outside of tropical northern Australia with a rich, stratified history of repeated human activity spanning nearly 50,000 years,” Mr Hamm said.

The research team used a series of novel dating procedures and statistical techniques to determine a precise occupation history for the archaeological site. A technique called single-grain optically stimulated luminescence (OSL) dating was used to determine the age of sediments that contained stone tools and fossil remains. Charcoal from fireplaces and bird eggshells, including those of a large extinct megapode bird (similar to a mallee fowl) and emus, were also used to date the chronology of occupation.

More than 2,000 bone fragments were assessed from the rock shelter and at least 16 mammal species identified, including the giant marsupial Diprotodon optatum. Bones and artefacts more than 46,000 years old were found together, providing the first reliable evidence of humans living alongside extinct Australian megafauna in the arid region.

“It’s unlikely that the largest known marsupial to have ever lived, the diprotodon, whose distant living relatives are thought to be the koala and the wombat, could have reached the Warratyi Rock Shelter on its own,” said Mr Hamm.

“The shelter is on a steep slope, and there were no teeth marks or predator breakage patterns found on the bones.

“We now have direct evidence for the co-existence of humans and megafauna in the interior deserts of Australia more than 46 thousand years ago. This will help us to better understand the causes of the continent-wide megafaunal extinction that took place around this time and how human populations have historically adapted to their environment,” said Mr Hamm.