50 years ago, an archaeological discovery in remote NSW turned the history of human evolution on its head.
Jim Bowler was the son of a Gippsland onion farmer, who grew up poor at the end of the Great Depression. As a young man he considered both taking over the family farm, and joining the priesthood, but eventually found his way to Melbourne University, where he studied Earth Sciences.
In 1967, Bowler joined the Australian National University, in Canberra, to study the historical impact of climate change on the Australian landscape.
He was particularly interested in ancient lakes and river systems, and had identified several sites in western New South Wales he thought worthy of investigation. One of these was an un-named dry lake on a cattle station, Mungo Station, 120 km from the Victorian border.
Lake Mungo, as Bowler dubbed the location, was an arid, inhospitable place.
The lake had dried out 15 000 years prior, and what remained was a barren, windswept plain. But what interested Bowler, was what lay beneath the ground.
There were three layers of sediment at Lake Mungo, and Bowler began investigating a band dated to between 25 000 and 50 000 years. His plan was to analyse the soil from this section, its chemical composition, to determine what the climate had been like in that era.
Instead, he found something totally unexpected.
During excavation of what had once been the lake’s shoreline, Bowler found several large clumps of seashells, above the water line.
These had been found at other locations across the globe, and one explanation for their existence was that they had been left by our ancient human ancestors.
This theory goes; early humans had been eating shellfish from a water source, and dumping the empty shells in one location, almost like a primitive garbage dump (called a ‘midden’).
But, at Lake Mungo, there was a problem with this explanation; the site should have been far too old for signs of human habitation.
In the 1960s, scientific theory held that Aboriginals had only begun arriving in Australia, northern Australia, in the last 20 000 years. The oldest human remains found to that time, in Kakadu, were dated to that period.
The Lake Mungo find, if confirmed, would mean Aboriginals had already made it to the southern part of Australia much earlier than that, more than doubling the time they had been inhabiting the continent.
It was a controversial theory. Bowler’s archaeological colleagues were dismissive.
On July 15, 1968, Bowler was at work at Lake Mungo when he spotted an unusual outcrop of soil:
‘Returning to camp in the late afternoon, an interesting block of soil carbonate lay exposed on an erosion surface.
And here were these burnt bones coming out of the soil. Bones. They were femurs and so forth. And I thought, ‘This is something I’m not going to touch’.'
- Jim Bowler
Bowler returned to Canberra to report his findings, supplemented with photographs.
The pictures of the burnt bones were sufficiently convincing that several of his colleagues returned to Lake Mungo with him, to conduct a fuller investigation. John Mulvaney, a legendary local archaeologist, would head up the expanded effort.
He was immediately excited by what he saw.
Our species, Homo Sapiens, arose in Africa.
More specifically, in sub-Saharan East Africa, around 400 000 years ago. The continent at this time was more lush than currently, with higher rainfall, and wide open grass plains.
Humans are an intelligent species, and adaptable; the first humans developed primitive tools out of stone, lived in small groups, developed basic communication, and coordinated their efforts to ensure their survival.
These advantages caused the human population to rise rapidly, and it quickly overran the natural resources of the African habitat.
There was only one solution available; migration.
‘They moved in small bands, and were explorers as well as settlers. In each unfamiliar region they had to adapt to new foods, and watch out for unfamiliar animals.
It was more like a relay race, than a trek. One group of 6 – 12 individuals would move into a new area and settle down, then the next group would come and leap frog them.’
- Geoffrey Blainey, ‘A Short History of the World’
This staged journey out of Africa took perhaps 200 000 years too complete, although no one is sure how long.
Different theories also suggest that it was not one continuous migration, but perhaps as many as four, caused mostly by changes in climate.
In any case, by around 75 000 years ago, Homo Sapiens had reached south-east Asia.
During this period, the world was experiencing an ice age.
Sea water became frozen in huge glaciers, that expanded far south into continental Europe and North America, resulting in lower sea levels elsewhere. Present day Australia was connected to present day Indonesia by a land bridge, that was easily traversable.
The first Aboriginals crossed this to enter Australia and began to fan out across the continent. By about 50 000 years ago, they had reached present day New South Wales.
Bowler, Mulvaney, and their team returned to Lake Mungo in March 1969.
They found the bones much as Bowler had photographed them, and began their investigation. The scientists originally thought that the bones were mostly likely burnt animal remains, but they quickly had to overturn this for something much more dramatic.
The team were stunned to discover pieces of human cranium in the bone pile. The burnt bones were later determined to be female, approximately 42 000 years old, and burnt as part of a post death cremation.
It is the earliest cremated human that has ever been discovered. The find was dubbed, Mungo Lady.
42 000 years, Lake Mungo was full of water, and teeming with life.
The lake was only one of several in the area; the ecosystem was a swampy marshland, surrounded by grasslands, not dissimilar to what earlier generations of Homo Sapiens would have found in Africa.
It is not known how many Aboriginals lived in the area at the time, but it is likely the population was relatively high. They lived in tribal groups, and were less nomadic than Aboriginals in other parts of Australia, due to the abundance of fresh water and food.
The men of Lake Mungo would have hunted mega fauna – giant kangaroo and wombat species, still thriving at this time – while the women would have collected shellfish, yabbies, seeds and emu eggs.
From this distance it seems like an idyllic lifestyle, tens of thousands of years before recorded history.
The discovery of Mungo Lady triggered further archaeological expeditions to Lake Mungo.
In 1974, Jim Bowler made his second dramatic discovery at the site; riding his motorcycle one afternoon, he simply spotted part of another human cranium sticking out of ground. This time, the find was even more remarkable; the almost fully preserved skeleton of a 50 year old male, to be dubbed Mungo Man.
Mungo Man was dated to around the same time as Mungo Lady, although interestingly he was not cremated. His body had been elaborately arranged, the limbs placed carefully, covered in dyed powder, and then buried.
This is also the oldest known example of a ritual burial, yet discovered.
The findings at Lake Mungo were significant on a variety of fronts.
It caused decades of theory around humanity’s long migration from Africa to be reconsidered; our early ancestors either left earlier, or travelled faster, than previously thought.
DNA analysis of the bones would also reveal that much of their genetic disposition had been determined before the migration began; there are overwhelming similarities between the bones in Lake Mungo, and earlier hominid bones found in Ethiopia and Morocco.
This was again at odds with the prevailing theories of the time, which held that most genetic divergence had occurred after migration from Africa.
Finally, the sophisticated nature of the burial sites, was considerably more advanced than had been expected, from such an early time period.
The fate of Mungo Lady and Man eventually became controversial.
Mungo Lady was returned to the traditional owners of Lake Mungo, the Paakantji, Ngyiampaa and Mutthi Mutthi tribes, in 1992. While these traditional groups wanted to re-bury her remains, the geographic instability of the area makes this difficult.
She is currently kept in a locked vault, in a Parks and Wildlife Building near the lake, while a final resting place is determined.
Mungo Man stayed in the possession of ANU for another twenty years.
Finally, after repeated requests from the traditional owners for repatriation, the remains were returned in late 2017. They were transported in a coffin made of 8 000 year old timber, and buried in an undisclosed location at Lake Mungo.