Modern humans active 20,000 years earlier than thought: Study

A new paper published in Nature has found evidence of modern humans in Southeast Asia (Sumatra) 20,000 years earlier than previously thought.

Melbourne, Aug 10: Modern humans may have exited Africa and arrived in Southeast Asia over 70,000 years ago, much earlier than previously thought, scientists said on Thursday. The study led by researchers at Macquarie University in Australia also suggests that humans could have potentially made the crossing to Australia even earlier than the accepted 60,000 to 65,000 years ago.

The dating of a cave site in West Sumatra in Indonesia, called Lida Ajer, provided researchers the first evidence for rainforest use of modern humans. "Rainforests are not the easiest place to make a living, especially for a savannah-adapted primate, so it suggests that these people were ahead of the curve in terms of intelligence, planning and technological adaptation," said Gilbert Price from University of Queensland in Australia. A team of researchers led by Dr Kira Westaway from Macquarie University, used advanced techniques to identify and date the ancient teeth, which were found in the Lada Ajer cave site.

Homo sapiens present between 63,000 and 73,000 years ago

As a result of thorough documentation of the cave, reanalysis of the specimens, and a new dating programme, it was confirmed that the teeth found there were of modern humans, Homo sapiens, and dated back 73,000 years.

"This is a significant finding because it supports emerging ideas that modern humans left Africa and reached Australia much earlier than we thought," said Michelle Langley of Griffith University. The evidence came in the form of two teeth, discovered by Dutch archaeologist Eugene Dubois in a cave on Sumatra in the late nineteenth century. The researchers confirmed the teeth belonged to Homo sapiens by comparing them to orangutan fossils found near the cave, and then dated them with electron spin resonance dating.

A barrage of dating techniques were applied to the sediment around the fossils, to overlying and underlying rock deposits in the cave and to associated mammal teeth, indicating that the deposit and fossils were laid down between 63,000 to 73,000 years ago, researchers said. The study was published in the journal Nature.

OneIndia News (with agency inputs)