‘Superhighways’ used by a population of up to 6.5 million Indigenous Australians to navigate the continent tens of thousands of years ago have provided new insights into how people thrived in harsh environments.
The international team of researchers, including from The University of Western Australia, used sophisticated modelling of past people and landscapes to reveal the routes that led to the early and rapid settlement of Australia by the First Australians.
The study, published today in Nature Communications, provides further evidence of the capacity and resilience of the ancestors of Indigenous people, and paints a picture of large, well-organised groups navigating tough terrain.
UWA Professor of Archaeology Peter Veth said the one of the major implications of the new modelling was that more ‘extreme’ environments like the Australian Deserts could have been occupied as early as 60,000 years ago.
“This would represent some of the earliest known occupation ages for arid zone adaptations by modern people in the world, outside of Africa and the Arabian Peninsula and on the southern dispersal arc to Australia,” Professor Veth said.
The group of multidisciplinary experts, led by Flinders University, used state-of-the-art modelling techniques to investigate where, how and when Indigenous Australians first settled in Sahul — the combined mega-continent that joined Australia with New Guinea when sea levels were lower than today.
The ‘peopling’ of Sahul could have taken as little as 5,000 years as people moved from the far northwest, all the way to Tasmania in the southeast.
Models also predict that the total population of Sahul could have reached as much as 6.5 million people, according to the researchers from the Australian Research Council Centre of Excellence for Australian Biodiversity and Heritage (CABAH).
Many Aboriginal cultures believe people have always been here, while others have strong oral histories of ancestral beings arriving from the north.
The study used real-world data about long-distance dispersal of people, human survival, fertility rates and the chance of natural disasters in combination with principles of human ecology and behaviour and with anthropological, ecological and environmental data to model the peopling of Sahul.
Data for the 10 million sqkm super-continent were used to develop a simulation model and run more than 120 scenarios to predict population size and growth rate. Strongest support was found for the arrival of people 50,000 or 75,000 years ago, with the average establishment rate of 1 km per year emerging from the model, giving rise to a maximum population of up to 6.5 million people.
Professor Veth said early settlers had advanced maritime capabilities and appeared to have quickly settled the tropical north from at least 65,000 years ago.
“They then metaphorically ‘sailed’ into the Australian deserts having the required skills and knowledge to tap onto unique desert waters, animal and plant foods and completely different rainfall patterns,” he said.
“UWA has a current program aiming to date the oldest Aboriginal habitation sites in the vast deserts of Western Australia.”
Future work could inform the search for undiscovered archaeological sites, or even apply the techniques to forecast the movements of human migration in the near future, as populations flee drowning coastlines and climate disruptions.