115,000-year-old bone tools unearthed in China

Researchers have discovered 115,000-year-old bone tools in China, which suggest that the toolmaking techniques mastered by prehistoric humans there were more sophisticated than previously thought.

Marks found on the excavated bone fragments show that humans living in China in the early Late Pleistocene were already familiar with the mechanical properties of bone and knew how to use them to make tools out of carved stone.

These humans were neither Neanderthals nor sapiens, according to the research published in the journal PLOS ONE.

"These artifacts represent the first instance of the use of bone as raw material to modify stone tools found at an East Asian early Late Pleistocene site," said Luc Doyon from the University of Montreal in Canada.

"They've been found in the rest of Eurasia, Africa and the Levante, so their discovery in China is an opportunity for us to compare these artifacts on a global scale," said Doyon.

The seven bone fragments analysed by researchers were excavated between 2005 and 2015 at the Lingjing site in central China's Henan province.

The artifacts were found buried at a depth of roughly 10 metres.

At the time, the site was being actively used as a water spring for animals.

Prehistoric humans likely used these water supply points for killing and butchering their animal prey, researchers said.

The bone fragments were dated using optically stimulated luminescence (OSL), a method widely used by geologists for dating the sediment layers in which tools are found.

The researchers identified three types of bone retouchers, known as soft hammers, that were used to modify stone (or lithic) tools.

The first type was weathered limb bone fragments, mainly from cervid metapodials, marginally shaped by retouching and intensively used on a single area.

The second type was long limb bone flakes resulting from the dismemberment of large mammals, used for quick retouching or resharpening of stone tools, Doyon said.

The third type was a single specimen of an antler of an axis deer that, close to its tip, shows impact scars produced by percussing various lithic blanks, he said.