John Sherwood roams an ancient, eroded cliff above the sea at Warrnambool, in south-west Victoria, willing the depths of time to reveal one last piece of incontrovertible evidence that would alter the world’s knowledge of humankind’s path from forever.
Layered into the cliff and scattered upon surrounding dunes are the leftovers of ancient feasts and campfires proven to stretch back at least 35,000 years.
Deeper than that, however, lies a mystery with the tantalising prospect of upending accepted understanding of the prehistory not only of Aboriginal Australia, but of humans’ trek out of Africa.
If proven to be the result of human manipulation, blackened stones in hearth-like circles and broken shells found embedded in the cliff at Point Ritchie, a place known to the Indigenous people of south-western Victoria as Moyjil, would mean that Aboriginal people lived there about 120,000 years ago.
This requires a deep breath, for 120,000 years is almost twice the period currently proven to be the stretch of Indigenous habitation of Australia.
It is also longer ago than most experts believe humans walked out of Africa to begin populating the Earth.
John Sherwood and other eminent scientists, with the collaboration of Indigenous representatives of three traditional owner groups of the Gunditjmara nation – the Eastern Maar, the Kuyang Maar and the Gunditj Mirring – have been working on the mystery at Warrnambool for 11 years, the cliff and its dunes giving up secrets as erosion advances year by year.
Their findings – six papers written by a total of 17 academic authors – were published by the Royal Society of Victoria several months ago, stirring widespread interest in archaeological and scientific circles.
There was, unsurprisingly, scepticism, too.
But those undertaking the research were also treated with considerable respect, for these were no dreaming beachcombers.
Among the leading figures taking part were geologist Jim Bowler, who in 1974 discovered the remains of the 42,000-year-old “Mungo Man” in the Willandra Lakes region of NSW, and anthropological archaeologist Professor Ian McNiven, of Monash University.
John Sherwood, an environmental scientist and associate professor at Deakin University’s Warrnambool campus, is a member of the team. The site has held him in thrall for many years. The possibilities, he says, keep him up at night.
But he concedes definitive evidence of humans living at this spot 120,000 years ago remains frustratingly just out of reach.
“I describe the evidence to this point as compelling, but not conclusive,” he tells me when I pull in on my motorcycle at Point Ritchie/Moyjil during my tour along the Great Ocean Road.
Dr Sherwood plunges off into the dunes, leading me and photographer Justin McManus on an intriguing trek back through time, the Hopkins River draining to the sea not far away.
It turns out to be impossible not to be captivated by what is plain to see, what has been discovered and what might yet be waiting to be found.
Dr Sherwood heads first to a site high up on the dunes where lie scattered clusters of broken shells, the leavings of endless feasting known as middens, some dated to 1000 years ago, and others to 6000 years.
Not far away, but further down the cliff, he shows us vastly older middens.
Here, too, are stone camp hearths, the carefully arranged circular layout of carbon-sooted cooking stones clear even to the untutored eye, but fused into a shelf of calcrete.
This alone is an immensely important find.
The campfires and the remnants of shellfish, also fused into the rock, sat beneath a layer of volcanic ash that settled after the last eruption of what is known as Tower Hill, its craters and lakes nowadays a major attraction between Warrnambool and Port Fairy.
The last eruption occurred about 35,000 years ago, the ash smothering those ancient cooking fires.
“I was blown away when we found fragments of a meal that was eaten somewhere between 35,000 and 50,000 years ago,” says Dr Sherwood.
But beneath that lies a much older layer where more broken shells and what appear to be round hearths with stones blackened by fire have been found.
Here, then, Dr Sherwood has led us to perhaps the most intriguing mystery of prehistoric Australia.
This layer has been dated by techniques known as optically stimulated luminescence, thermoluminescence and amino acid racemisation at 120,000 years of age.
Until now, the oldest proven evidence of Aboriginal occupation of Australia is 65,000 years at a site known as Madjedbebe in the Kakadu National Park, unveiled in July 2017.
“You can understand that many in the archaeological community are sceptical,” says Dr Sherwood.
“We really need definitive evidence like skeletal remains or something clearly shaped by human hands.”
One problem is that seagulls are known to drop and break open shells.
Were seagulls responsible for this 120,000-year-old shell dump in such close proximity to middens proved to be created by humans?
And what of the stones that appear to have been placed in the shape of a hearth, and blackened by fire?
It has been established that permanent blackening of stones requires a consistent hot fire burning for a minimum of 45 minutes to an hour, like a campfire, says Dr Sherwood. Could there have been a bushfire that burned hot in the same place for such a time?
“We don’t know,” he says.
The sense of both frustration and teetering on belief in great discovery permeates the summary of the papers published by the Royal Society.
“In the absence of bones, stone flakes or any independent trace of people, the notion of occupation at 120 ka [120 thousand years] currently remains difficult to credit,” the authors stated.
“However, marine shells, stones in unexplained depositional context and fire resemblance to hearth, successively diminish the possibility of a natural explanation. That absence leaves the currently unlikely option of human agency as the most likely alternative.”
Meanwhile, an internationally regarded specialist in microscopic examination and testing of human fireplaces, Professor Paul Goldberg of Boston University, Massachusetts, recently travelled to Warrnambool and gathered samples from two suspected ancient fireplaces.
His examination, in search of human signatures, is expected to be completed by around March.
At which point, those who have devoted so much of their life to this great mystery, like Dr Sherwood, and those of the Gunditjmara nation who simply know their people have been in Australia for unimaginable time, may be closer to an answer.
Meanwhile, the wind blows and the sea crashes upon sand, and John Sherwood wanders a Warrnambool cliff almost older than human time; a cliff that both reveals and withholds ancient secrets.
Tony Wright is the associate editor and special writer for The Age and The Sydney Morning Herald.