A cave on the island of Timor has given archaeologists an important clue to the route taken by historical people after they first made their strategy to the Australian continent.

It’s identified from archaeological proof in Australia’s Northern Territory that folks had been there at the very least 65,000 years in the past. At the moment, when sea ranges had been decrease, Australia and New Guinea had been half of a bigger landmass referred to as Sahul.

Researchers consider there are two doubtless routes folks may have taken from South-East Asia to Sahul. One is a southern route by way of Timor. Alternatively, Homo sapiens may have travelled by way of Sulawesi, an island to the north of Timor.

Now, Sue O’Connor on the Australian Nationwide College in Canberra and her colleagues consider they’ve discovered proof ruling out the likelihood that the primary arrivals got here by means of Timor.

In different places on Timor, the oldest proof of human occupation was lower than 50,000 years outdated. Archaeologists had been unable to search for older artefacts as, in any respect the opposite websites they studied, they hit bedrock somewhat than sediment layers that would probably include proof of an earlier presence, says O’Connor.

In 2019, her staff dug a brand new pit at a cave known as Laili, on the north coast of East Timor, and found a wealthy deposit of archaeological proof together with tens of 1000’s of stone instruments, proving that people had occupied the island for 44,000 years.

Crucially, nonetheless, this layer of occupation was underlain by sediments with no proof of people. This implies it’s doubtless that earlier than 44,000 years in the past, folks had been absent, says O’Connor.

“That is the primary time in Timor that now we have sterile, non-occupation layers beneath proof of individuals’s presence,” she says.

O’Connor says such a transparent boundary between no proof of people adopted by tens of 1000’s of years of artefacts known as an “arrival signature”.

The cave’s outstanding location and entry to assets offers the researchers confidence that it’s unlikely to have been missed by any early people travelling by means of the world.

“It’s a very, actually large cave with an enormous flowing river in a braided floodplain and really near the coast,” says O’Connor. “It’s an ideal place for folks to ascertain an occupation base camp. You couldn’t discover a extra preferrred setting.”

Due to the proof that folks had been in Australia 65,000 years in the past however not in Timor till 44,000 years in the past, it means people probably migrated by way of the islands to the north, says O’Connor.

“Wanting on the layers in Laili cave, it’s like ‘bang’ – you’ll be able to actually see clearly when the folks arrive,” she says. “It was like a line had been drawn between the 2 layers – earlier than folks and after folks. It was so clear.”

Peter Veth on the College of Western Australia says the case for a later date for the occupation of Timor is constructing. He says historical Australians weren’t as remoted as was as soon as believed and that there have been most likely a number of waves of migration to Sahul.

“I believe an earlier northern route appears believable. This can be a extremely important web site as, primarily based on a broad suite of shellfish, fish, crustacea and different assets discovered within the cave, it reveals there was a totally fledged maritime financial system in place when Timor was settled.”