12,000-year-old stones may be oldest example of wheel-like tools

A set of 12,000-year-old pierced pebbles excavated in northern Israel may be the oldest known hand-spinning whorls – a textile technology that may have ultimately helped inspire the invention of the wheel.

Serving as a flywheel at the bottom of a spindle, whorls allowed people to efficiently spin natural fibres into yarns and thread to create clothing and other textiles. The newly discovered stone tools represent early axle-based rotation technology thousands of years before the first carts, says Talia Yashuv at the Hebrew University of Jerusalem.

“When you look back to find the first vehicle wheels 6000 years ago, it’s not like it just came out of nowhere,” she says. “It’s important to look at the functional evolution of how transportation and the wheel evolved.”

Yashuv and her colleague Leore Grosman, also at the Hebrew University of Jerusalem, studied 113 partially or fully perforated stones at the Nahal Ein Gev II site, an ancient village just east of the Sea of Galilee. Archaeologists have been uncovering these chalky, predominantly limestone artefacts – probably made from raw pebbles along the nearby seashore – since 1972.

3D scanning revealed that the holes had been drilled halfway through from each side using a flint hand drill, which – unlike modern drills – leaves a narrow and twisting cone-like shape, says Yashuv. Measuring 3 to 4 centimetres in diameter, the holes generally ran through the pebble’s centre of gravity.

Drilling from both sides would have helped balance the stone for more stable spinning, says Yashuv. Several of the partially perforated stones had holes that were off-centre, suggesting they might have been errors and thrown out.

The team suspected that the stones, weighing 9 grams on average, were too heavy and “ugly” to have been beads and too light and fragile to be used as fishing weights, says Yashuv. Their size, shape and balance around the holes convinced the researchers that the artefacts were spindle whorls.

To test their hypothesis, the researchers created replicat whorls using nearby pebbles and a flint drill. Then they asked Yonit Kristal, a traditional craftsperson, to try spinning flax with them.

“She was really surprised that they worked, because they weren’t perfectly round,” says Yashuv. “But really you just need the perforation to be located at the centre of mass, and then it’s balanced and it works.”

If the stones are indeed whorls, that could make them the oldest known spinning whorls, she says. A 1991 study on bone and antler artefacts uncovered what may be 20,000-year-old whorls, she adds, but the researchers who examined them suggested the pieces were probably decorative clothing accents. Even so, it is possible that people were using whorls even earlier, using wood or other biological materials that would have since deteriorated.

The finding suggests that people were experimenting with rotation technology thousands of years before inventing the pottery wheel and the cart wheel about 5500 years ago – and that the whorls probably helped lead to those inventions, says Yashuv.

Carole Cheval at Côte d’Azur University in Nice, France, is less convinced, however. Whorls work more like a top than a wheel, she explains.

And while the artefacts might very well be whorls, the study lacks microscopic data that would reveal traces of use – as yarns would have marked the stones over time, Cheval says.

Trace analysis was “beyond the scope” of the current study, says Yashuv.

Ideally, researchers studying ancient whorls would be skilled in spinning themselves – which the study authors were not, says Cheval. “It really changes the way you think about your archaeological finds,” she says.

Source: Humans - newscientist.com