A drawing from Blombos Cave made with ochre crayon on silcrete stoneCraig Foster

Around 73,000 years ago, in a cave now known as Blombos, someone took a pointed lump of iron-rich rock—ochre—and dragged its tip across another rock, leaving behind a pattern of red, crosshatched strokes. The identity of the marks’ creator is unknown. Their intentions are unclear. But the red marks still persist on a 1.5-inch-long piece of stone, discovered by a team of researchers led by Christopher Henshilwood from the University of Bergen. If Henshilwood’s interpretation of the marks’ origins is correct, they make up the oldest abstract drawing ever found, predating the previous record holders by at least 30,000 years.

“It doesn’t make the … people of Blombos Cave artists, but it suggests that they started being interested by graphical designs,” says Chantal Tribolo from Bordeaux Montaigne University, who studies symbolic behaviors in early humans and was not involved in the new find. “What they exactly wanted to do or express with these sketches remains to be discovered.”

For a long time, the oldest known drawings and paintings were found on the walls of caves in France and Spain, and were between 30,000 and 40,000 years old. Their antiquity fit with a prominent Eurocentric narrative in which humans migrated out of Africa, and only then went through a “creative explosion” that led to symbolic thought, advanced culture, and modern behavior. But this story has now been thoroughly dismantled by a string of discoveries, including those that Henshilwood and his long-time colleagues Francesco d’Errico and Karen van Niekerk have made in Blombos.

The cave lies about 200 miles east of Cape Town, on South Africa’s southern coast. Henshilwood started working there in 1991; a decade later, he and his colleagues found two pieces of ochre that had been engraved with crosshatched lines, and were at least 70,000 years old. At the time, they were the oldest abstract art ever found. Henshilwood took them as evidence that humans in Africa already had the capacity for symbolic thought long before they started painting on European cave walls.

A few years later, his team found jewelry in Blombos—a set of 77,000-year-old beads that had been made from shells and decorated with ochre. Shortly after, they found an entire 100,000-year-old paint-making workshop: stones for grinding and hammering ochre stones, a bone rod for stirring the liquefied paste, and abalone shells for storing it.

But despite finding several engravings, “we never found any drawings, and it was kind of strange,” Henshilwood says. It wasn’t for a lack of tools. During its excavations, his team had found several crayons—ochre flakes that had been ground to a point and could leave red marks when pressed on stone. “We knew they had been used. We never knew what they had been used on,” he said.

Magnus M. Haaland

That changed when Henshilwood’s colleague Luca Pollarolo started combing through stone artifacts that had been excavated in 2011, and noticed a red crosshatch pattern on one of them—six lines going in one direction, and three more that cross them diagonally. It looked like part of a drawing, although “it was pretty dull looking,” Henshilwood says. “I was convinced, but not totally convinced.”

Chemical tests reassured him. They showed the signatures of two distinct kinds of ochre—one from the red lines, and another from the rock itself. The evidence suggests that the rock was once part of a larger grindstone that was used to process ochre. At some point, someone cleaned the grindstone, drew red lines on it, and then flaked a piece off.

To test that idea, the team made ochre crayons of its own, and used them to mark rocks from the same part of Blombos. “We produced something that exactly matched the drawing we found,” Henshilwood says, right down to a microscopic scale.

But there’s some circularity in those experiments, says Lyn Wadley, an archeologist at the University of Witwatersrand. The team thinks the lines were made through intentional drawing, and it showed that intentional drawing could have produced such lines. What about other activities? Across other South African caves, ochre was clearly used in many different ways. “If after performing a variety of activities with grindstones, grindstone fragments, and pieces of ochre, the only marks to match the archaeological ones are from drawing with an ochre crayon, I would be convinced that their interpretation is the most likely one,” Wadley says.

That said, “it wouldn’t be a surprise to find that people at Blombos were able to draw 73,000 years ago,” she adds. They had clearly been processing ochre for millennia before then, and making engravings that used a similar crosshatch design. Besides, archaeologists have found far older abstract engravings in other parts of the world, including on a 370,000-year-old bone from Bilzingsleben, Germany, and on a 540,000-year-old shell from Trinil that was likely carved by Homo erectus. Given these much older finds, I wondered why a 73,000-year-old drawing should matter.

“With the drawing, there’s a new dimension,” Henshilwood told me. “It means you can put a crayon into a bag, walk over the landscape, and mark a rock or tree, without needing to make paint or engrave something. It’s the equivalent of us having a ballpoint pen; [it makes it easier to] communicate with other groups of people.”

But what were they saying? Crosshatched patterns appear repeatedly in Blombos, on drawings and engravings. They appear at another site that Henshilwood studies, more than 30 miles away. They appear on pieces of ostrich eggshells from the other side of South Africa. “That pattern almost seems to be part of the human repertoire, but the meaning probably changed over time,” Henshilwood says.

“While the similarity of the ochre lines to the engraved ones argues for intentionality in both cases, it is hard for us moderns to read the context or meaning behind such early acts,” says Alison Brooks, an anthropologist at George Washington University. They could have been made to “represent an image or figure, impose a personal mark or signature on something, to sharpen a tool or crayon, or to keep a record or tally.”

Earlier this year, Brooks announced the discovery of 300,000-year-old rocks from Olorgesaillie, Kenya, that had been processed to create ochre paint. They had clearly been deliberately ground with some chisel-like tool to extract the red powder within. No one knows what they used that paint to do, but it’s further evidence for the antiquity of symbolic human behavior. It’s all part of a new view of our origins, in which our bodies and culture arose in a complicated fashion that involved the entirety of Africa—our continent of birth.

“I don’t want to give the impression that this is all about Blombos, and there’s some unbelievable breakthrough at 73,000 years,” Henshilwood says. “There wasn’t. It was part of a long process of Homo sapiens becoming more and more modern, and we’re picking up the evidence for that bit by bit.”

“It’s just hard to find that evidence!” he adds. “We were lucky to find that drawing, and hopefully we’ll find more.”

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