The oldest drawing, 73,000 years old, looks like a hashtag

And you thought the Mona Lisa was old.

Researchers say they found the first known drawing on a stone fragment in South Africa. The simple hatch pattern dates back to 73,000 years in the Middle Ages, making it 30,000 years older than the oldest known abstract designs.

The drawing, found in a cave 300 km east of Cape Town, was engraved with red ocher pigments. The stone canvas only measures 1.6 inches (4 centimeters) and would have belonged to a larger grindstone, which means we probably only see part of the original drawing.

Archaeologists have searched the cave of Blombos since 1991 and found bone punches, spear points, shell beads and ocher engraved with geometric patterns.

The 73,000-year-old silicon flakes, which currently carry the L13 title, which is not too valuable, were unearthed in 2011. But it's only on Wednesday that a team of international researchers led by Christopher Henshilwood of their discoveries on the rock. Their research appears in the journal Nature.

The team studied the nine red lines on the flake using techniques involving advanced microscopes and lasers. They concluded that the marks were not natural, but had been intentionally applied to the stone.

"This shows that the first Homo sapiens in southern Cape used different techniques to produce similar signs on different media," said Henshilwood in a statement. "This supports the hypothesis that these signs were of a symbolic nature and represented an inherent aspect of the modern behavioral world of these African Homo sapiens, the ancestors of all of us today."

In this case, scientists say that the techniques involved simple strokes of a sharp ocher "pencil" with a peak of 1 to 3 millimeters thick (among its findings in 2011, the team has also recovered snail shells containing residues of a ocher-rich paint). Our ancestors also used friction movements to decorate the stone, say the scientists.

But what does drawing represent? The sharpening of the Stone Age tool of a man is the art of another man, so it is fair to consider this as a Rorschach test. Some people might look at it and see cross lances or entangled branches. Others might see an old hashtag.

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