Modern humans in South Africa may have been using a sophisticated tool sharpening technique as far back as 75 000 years ago, according to researchers, including a scientist from the University of the Witwatersrand in Johannesburg.
“This research also indicates that this technology may have first been invented and used sporadically in Africa before its later widespread adoption in Western Europe, North America and Australia,” said the university, as the findings were published in the journal Science today.
The research quoted Dr Paola Villa, a curator at the University of Colorado Museum of Natural History in the US, as saying the innovation known as pressure flaking is considered an example of the development of techniques seen as “advanced” or showing “modern behaviour”.
Pressure flaking is a retouching technique used to shape stone artefacts by exerting pressure with the narrow end of the tool close to the edge of blades or weapons. It makes it easier to control the sharpness, thickness and overall shape of tools like spearheads and stone knives.
Most stone materials usually need to be heated before they can be pressure flaked, so researchers replicated the process which they believe may have been used, with the help of silcrete artefacts found in and near Blombos Cave, near Still Bay in Western Cape, to test their theory.
They analysed 159 points and fragments, 179 other retouched pieces and more than 700 flakes from a layer in the cave which dated to between 76 000 and 72 000 years ago.
“At least half of the ancient, finished points at Blombos Cave were retouched by pressure flaking,” said Villa.
Shell beads, engraved ochre and other evidence of early modern human behaviour have previously been found at Blombos.
The scientists involved in the research were: Villa, Dr Vincent Mourre of the University of Toulouse in France and Professor Christopher Henshilwood of the Wits Institute for Human Evolution.