A new study published in the journal Science has found the oldest examples of a highly-important Stone Age innovation known to scientists as the Oldowan toolkit, together with the oldest evidence of hominins consuming very large animals. According to the experts, early human ancestors used these ancient stone tools to butcher hippos and pound plant material roughly 2.9 million years ago along the shores of Africa’s Lake Victoria.
In addition, excavation at the site – called Nyayanga and located on the Homa Peninsula in western Kenya – also unearthed a pair of massive molars belonging to humans’ close evolutionary relative, the Paranthropus, suggesting that these hominins rather than those from the genus Homo may have been the earliest toolmakers.
“The assumption among researchers has long been that only the genus Homo, to which humans belong, was capable of making stone tools,” said study senior author Rick Potts, a paleoanthropologist at the Smithsonian National Museum of Natural History. “But finding Paranthropus alongside these stone tools opens up a fascinating whodunnit.”
The Oldowan toolkit included three types of stone tools: hammerstones, which can be used for hitting other rocks in order to create tools or for pounding other materials; cores, an angular or oval tool that, when struck at an angle with a hammerstone, splits off a piece, or flak – another type of tool that can be used as a cutting or scraping edge or further refined with a hammerstone.
By contrast to the only other stone tools known to have existed – a collection of 3.3-million-year rather rudimentary artifacts found at a site called Lomekwi 3 in Kenya – Oldowan tools are much more sophisticated. They are systematically produced by using “freehand percussion,” a process through which the core was held in one hand and then struck with a hammerstone at just the right angle to produce a flake. This method requires significant skill and dexterity.
By analyzing the wear patterns of 30 of the Oldowan tools discovered at the site, the scientists found that they had been used to cut, scrape, and pound both large animals and plants.
“This is one of the oldest if not the oldest example of Oldowan technology,” said study lead author Thomas Plummer, an expert in Early Stone Age technology at the City University of New York (CUNY). “This shows the toolkit was more widely distributed at an earlier date than people realized, and that it was used to process a wide variety of plant and animal tissues. We don’t know for sure what the adaptive significance was but the variety of uses suggests it was important to these hominins.”
“East Africa wasn’t a stable cradle for our species’ ancestors.’ It was more of a boiling cauldron of environmental change, with downpours and droughts and a diverse, ever-changing menu of foods. Oldowan stone tools could have cut and pounded through it all and helped early toolmakers adapt to new places and new opportunities, whether it’s a dead hippo or a starchy root,” concluded Potts.
By Andrei Ionescu, Earth.com Staff Writer
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