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Cave art and harpoon tips show African roots of our creative genius

Robin McKie

Source - http://www.theguardian.com/science/2014/oct/11/cave-paintings-indonesia-african-roots?

The discovery of wall paintings in Indonesian caves suggests that the human ability to express ourselves began before we trekked out of Africa

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Images of animals Photograph: Kinez Riza/AFP/Getty Images

On the third-floor corridor of the Smithsonian Natural History Museum in Washington, in a battered metal locker, archaeologist Alison Brooks has filed away two small cardboard boxes. Each contains several toothbrush-sized instruments made of bone. With their delicate serrated blades, these would have been highly effective weapons.

Nor is there doubt about their targets – for the exquisitely carved blades were found under nine feet of mud at Katanda, on the banks of the Semliki river in the Democratic Republic of the Congo. “These were harpoon heads,” said Brooks. “Some of the best I have come across.”

The little weapons, found by Brooks and her husband, John Yellen, more than a decade ago, show evidence of remarkable craftsmanship. Yet they are more than 90,000 years old. In fact, they are some of the earliest instruments ever shaped by modern humans using a material other than stone or wood.

It is an intriguing combination – startling sophistication mixed with deep antiquity – and it gives the blades considerable importance to science, says Brooks. They show, she believes, that our species’s final intellectual transition, from apeman to modern human, must have occurred at a different time and place than previously thought.

In the past, it was reckoned that men and women acquired their full intellectual potential and artistic grace only when they reached Europe 40,000 years ago, having trekked out of Africa between 60,000 and 70,000 years ago on a journey that also took us to Asia, Indonesia, and Australia. Until then, Homo sapiens was not quite the full Monty when it came to art and invention, it was argued. After all, it was only in Europe that we began making complex tools and started to paint magnificent versions of lions, mammoths and horses on cave walls such as those found at Chauvet and Lascaux in France.

However, the work of Brooks and Yellen, in common with a growing number of other scientists, suggests this notion is incorrect. She believesHomo sapiens reached its full intellectual and artistic potential much longer ago and much deeper in our prehistory: possibly more than 100,000 years ago when we were still evolving in Africa. In other words, our technological and artistic roots are far deeper than we believed, an error that came about because, for a long time, we lacked any evidence in Africa that could confirm our intellectual antiquity.

But as the years have gone by, other scientists – working in the wake of the opening up of South Africa after the end of apartheid – have made further intriguing discoveries to support this theory: tiny 70,000-year-old flint points, which may be the first arrows ever made, and beautifully crafted pieces of ochre that suggested works of arts and jewellery were being created at this time. Other finds indicate human beings had learned how to use heat to treat rocks in order to make intricate quartz blades, a technology that was previously thought to have been a recent European invention.

All of this work pointed to ancient African origins for the soul of human art and inventiveness though the evidence was not completely emphatic, researchers acknowledged. However, that lack of conviction changed last week when an Australian-Indonesian team of researchers published a paper in Nature  that provided details of a set of striking works of figurative art that had been painted on rock walls in Indonesia and which were found to be as old as many of the great paintings made by our European ancestors in Spain and France, including those at Chauvet and Lascaux.

These newly dated paintings adorn the walls of caves and shelters at the foot of spectacular limestone towers near Maros in south-west Sulawesi and include hand stencils, created by spraying or spitting a mouthful of paint over an outstretched hand, as well as images of animals such as the pig-deer or babirusa.

While most of the animals in the paintings are identifiable, the artists have also exaggerated aspects of the beasts, perhaps to accentuate features that interested them, said Adam Brumm, from the University of Wollongong in New South Wales, Australia, and a co-author of the study. “The paintings are feats of great imagination and they provide the first real insight into the artistic culture and symbolic conventions of early modern humans in Asia.”

The crucial point is that the discovery shows that cave art, often considered the greatest achievement of Stone Age humans, was being made at opposite ends of the Old World at about the same time, a point stressed by the researchers’ leader, Maxime Aubert, another Wollongong researcher. “This suggests these practices have deeper origins, perhaps in Africa before our species left this continent and spread across the globe.”

It is a view that is backed by Chris Stringer, of the Natural History Museum, London. “It has been argued that the final spark that brought modern humans to their full intellectual status only occurred when we entered Europe,” he said. “But this discovery shows modern humans were behaving with the same sophistication in Indonesia. If nothing else, that should allow us to move away from Eurocentric ideas on the development of figurative art to consider the alternative possibility that such artistic expression was a fundamental part of human nature 60,000 years ago when we still lived in Africa.”

When Aubert and his team began their work in Sulawesi it was thought that the paintings, which were first discovered in 1950, were only about 10,000 years old. Their real antiquity – now shown to be between 35,000 and 39,000 years old – indicates that they compare closely in age to the oldest known rock art in Europe: 40,800 years old for a painting in El Castillo cavern, Spain, while great French cave paintings of Chauvet have been dated as being around 35,300 to 38,800 years old. “The bottom line is that cave art was practised in Europe and in south-east Asia at about the same time,” said Wil Roebroeks, of Leiden University, Netherlands, in a commentary in Nature about the Aubert group’s research.

In other words the artistic genius responsible for Chauvet and Lascaux was not some newly acquired prowess that we picked up as we entered Europe but was part of our African birthright. As the art critic John Berger once remarked about Europe’s ancient rock art paintings: “There was grace from the start.” Science now suggests how right he was. That grace came from our African roots.

This point is backed by Stringer. “It is sometimes claimed that it was our entry to Europe that provided the final trigger that brought about the flowering of our full artistic ability. But we now have convincing evidence to show that this capacity was in evidence half a world away at the same time. Either you assume modern humans suddenly achieved that full creativity on two separate occasions or you take the view that we already had achieved that status before we left Africa and that we took our creativity with us on our journey round the globe.”

In the wake of the Sulawesi discoveries, scientists are now looking at the ages of other rock paintings around the globe including highly complex cave art that has been found in Australia but which has confounded scientists to date them. These could have ages of around 40,000-50,000 years, researchers suggest.

Certainly, the idea that the roots of human intellect, our capacity for symbolic reasoning, our inventiveness and our ability to create works of figurative art, are part of our African birthright now looks much stronger. In short, our minds were shaped by our evolution on the continent, a view summed up Chris Henshilwood of the University of Witwatersand, in Johannesburg: “African people, from whom we are all descended, were modern in their behaviour long before they got to Europe.”

DATING THE PAINTINGS

The team, which was led by Maxime Aubert, an archaeologist at the University of Wollongong in New South Wales, used a technique called uranium-thorium dating to calculate the age of the paintings found in seven different caves at Maros in Sulawesi, Indonesia.

Thin layers of calcite containing traces of uranium were deposited on the paintings as mineral-rich waters trickled down cave walls over thousands of years. Uranium decays into thorium at a specific rate and the team were able to calculate an accurate age of the painting by analysing levels of the two elements in the calcite. One painting – of a stencilled hand created by spraying pigment over a person’s arm – was dated as being at least 39,000 years old while one of a pig deer was dated at 35,400.

And these are minimum ages,” said Chris Stringer, of the Natural History Museum in London. “They could be several thousand years older.”