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 geologist Eugene 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.
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.