A team of researchers announced on Thursday that early humans were living in the rainforests of Indonesia over 70,000 years ago, 20,000 years before what was previously believed.
Researchers from the Australian Centre for Human Evolution (ARCHE) collaborated with an international team on the discovery in the Sumatran rainforest, with the results suggesting that early humans could have migrated to Australia even earlier than expected.
One of the researchers on the project, Julien Louys from the ARCHE, told Xinhua news agency that the aim of the project was to "re-discover and re-analyse" Pleistocene fossil sites.
"Essentially, we knew that modern human remains had been recovered from one of these sites (Lida Ajer)," Louys said.
"We wanted to collect samples for dating, as well as looking at what sorts of environments these humans were living in."
According to Louys, the remains of the early humans that were found were also located amongst other Sumatran rainforest mammals - which means it was likely that they were living in the similarly challenging rainforest environment for those of limited technological capability.
"Living in rainforests is difficult without sophisticated technology, as protein is hard to come by - rainforests typically have cryptic or canopy-loving animals that can be hard to catch - and carbohydrates are not common," Louys said.
"The humans survived in these environments indicates that they were behaviourally modern, and had the necessary technologies to gather these resources."
In order to survive, Louys believes that these early humans would have to have developed methods that were sophisticated for humans at that time, with adaptation to the unforgiving environment being key.