03 December 2014 by Catherine Brahic
A shell etched by Homo erectus is by far the oldest engraving ever found, challenging what we know about the origin of art and complex human thought
THE artist – if she or he can be called that – was right-handed and used a shark’s tooth. They had a remarkably steady hand and a strong arm. Half a million years ago, on the banks of a calm river in central Java, they scored a deep zigzag into a clam shell.
We will never know what was going on inside its maker’s head, but the tidy, purposeful line (pictured above right) has opened a new window into the origins of our modern creative mind.
It was found etched into the shell of a fossilised freshwater clam, and is around half a million years old – making the line by far the oldest engraving ever found. The date also means it was made two to three hundred thousand years before our own species evolved, by a more ancient hominin, Homo erectus.
“It is a fascinating discovery,” says Colin Renfrew, an archaeologist at the University of Cambridge. “The earliest abstract decoration in the world is really big news.”
The shell was dug up in Trinil, Indonesia, in the 1890s by Dutch geologistEugene Dubois, and was one of many fossil finds in the area, including bones of Homo erectus and several animals.
The shell collection sat in a museum in Leiden, the Netherlands, for over a century. Seven years ago, PhD student Stephen Munro, now at the Australian National University in Canberra, was in the country for a few days and stayed with archaeologist Josephine Joordens of the University of Leiden. She was re-exploring the Dubois collection at the time, and as Munro was also studying ancient molluscs, Joordens encouraged him to take a look. Pressed for time, he photographed each one before heading back to Australia.
“A week later I received an email,” Joordens recalls. “He wrote that there was something strange on one of the shells and did I know what it was?”
Ever since then, Joordens and her team have been meticulously documenting all the Dubois clams. Sediment inside them and tiny grains pulled from cracks were dated, to reveal that they had been buried between 430,000 and 540,000 years ago (Nature, DOI: 10.1038/nature13962).
One turned out to be a tool, its sharpened edge probably used for scraping. Many were pierced where the clam’s muscle attaches to the shell. When the team made similar holes in live clams, the damage to the muscle forced them open.
“It must have been a fairly quiet riverine environment with lots of shells,” says Joordens. “Probably hominins living in the area exploited it.” She says the entire site was buried suddenly, possibly the result of a volcanic eruption or a flash flood.
Meanwhile, Francesco d’Errico, a palaeoanthropologist at the University of Bordeaux in France, known for his work on early hominin engravings, tried to replicate the etch, down to its microstructure. He tested three pointed tools: a flint, a shark’s tooth and a steel scalpel. The shark’s tooth – many of which were also found at the Java site – offered the closest match.
The experiments showed that the line is too deep and straight to have been made by an idle hand. Fresh Pseudodon clam shells have a dark brown coat, so the etch would have made a striking white line. All this suggests that it was made deliberately, and yet, unlike tools, the mark has no obvious function. It may have been a decoration, or a practice run for a decoration on another object.
That’s important because Homo sapiens was thought to be the first species to produce abstract, non-functional designs. No other animal, not even a chimpanzee, has ever been known to make non-functional markings.
“It’s very carefully done,” says Andrew Whiten, a psychologist and primatologist at the University of St Andrews in the UK. “There is a wonderfully straight section and the [etch] turns in one continuous line. That’s not just intentional but careful in what strikes as a very modern way. Apes aren’t doing that. It would be staggering if they did.”
So did the etching have some kind of meaning for its maker? And what can it tell us about the origins of complex human thought and artistic expression?
“We cannot look into the mind of the person who made it,” says Joordens. But we can speculate. One thing the marks suggest is that half a million years ago, these distant ancestors already had some sense of aesthetics.
“So far,” says Renfrew, “we haven’t had much indication that H. erectus was doing much other than making beautiful tools and hand axes.” Some see a sense of aesthetics in the tools – perhaps even making their owners more attractive to potential mates. But that is controversial and, besides, tools are undeniably useful.
Still, d’Errico suggests the lines might have been a sort of signature, indicating ownership. That would mean they had a function of sorts, but takes nothing away from their abstract nature.
“Whether the zigzag pattern had a specific meaning or was merely a sort of doodle seems irrelevant,” says David Edelman, a neuroscientist who was most recently at Bennington College in Vermont. What is significant is that the shape is not immediately linked to anything concrete or to survival.
“Regardless of intent, the very process of rendering a geometric form would seem to indicate the workings of a mind no longer tethered solely to the here and now, but capable of a uniquely abstract form of conscious ‘wandering’,” Edelman says.
The etch also suggests H. erectus was integrating different domains of knowledge – thought to be a key stage in the evolution of our creative minds. “Our results indicate that these shells were seen at the same time as a source of food, a raw material to make tools, and a canvas on which to produce engravings,” says d’Errico.
With only a few lines on a single shell, it is impossible to say how unusual the Trinil aesthete was at the time. It’s possible – likely, according to some – that many more etchings were made on materials that did not survive or remain to be found. Or the zigzag could have been the work of a rare early creative mind.
Either way, the Trinil shell offers a compelling insight. Bones tell us about how our ancestors looked and moved. They say very little about thoughts. So in the end, perhaps the most striking aspect is the etching’s familiarity. “In a way,” says Joordens, “it is emotionally touching, seeing something so old that looks like something you could have made yourself.”
This article appeared in print under the headline “Etched in time”