Toronto, Mar 20 (IANS): The toolmaking techniques mastered by prehistoric humans in China were more sophisticated than previously thought, suggests an analysis of 115,000-year-old bone tools discovered in the country.

Marks found on the excavated bone fragments show that our ancestors 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, according to the study published in the journal PLOS ONE.

"These artefacts 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," Doyon added.

Until now, the oldest bone tools discovered in China dated back 35,000 years and consisted of assegai (spear) points.

"Prior to this discovery, research into the technical behaviour of humans inhabiting China during this period was almost solely based on the study of tools carved from stone," said Doyon.

The seven bone fragments analysed by Doyon and his colleagues 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.

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.

Doyon explained that the researchers identified three types of bone retouchers, known as soft hammers, that were used to modify stone tools.

The researchers have not yet determined which hominid species the users of these prehistoric tools belonged to, although they do know that they lived during the same period as Neanderthals and Homo sapiens.