Archaeologists believe they have found the oldest stone tools ever recorded in Africa, and they weren't used by any human from the genus Homo. The tools, dating back 3.3 million years, are proof that some of the earliest ancestors of humans used tools several hundred thousand years before the rise of the genus Homo.
The stone flakes found are 700,000 years older than the oldest known tools to date, researchers said. Until now, the earliest known stone tools had been found at the site of Gona in Ethiopia and were dated to 2.6 million years ago.
The area surrounding Lake Turkana in Kenya has yielded many fossils relating to early human life. A team led by Sonia Harmand of Stony Brook University in New York was behind this most recent discovery.
In 2010, researchers based in Ethiopia revealed the discovery of animal bones dating back 3.4 million years, which showed cut marks indicating that humans made the marks using tools. This new discovery gave credence to the theory that early human ancestors used tools much earlier than originally believed.
However, the claim was immediately controversial with some arguing the cut marks might have simply been the result of trampling by humans or other animals.
Harmand and her team believe different. "The artifacts were clearly knapped and not the result of accidental fracture of rocks," Harmand told the annual meeting of the Paleoanthropology Society, which was held in San Francisco this week.
Knapping is the process of chipping flakes off a larger stone to form sharp edges that can then be used as a tool.
According to Harmand, the discovery of the tools was accidental. Her and her team were searching for evidence of Kenyanthripos platyops, an ancient human relative, but they went the wrong way and ended up at the site known as Lomekwi 3, west of Lake Turkana.
After discovering a number of tools close to the surface, they dug down further and eventually recovered 20 preserved flakes, source stones and anvils that had been used as bases on which to knap stones.
The 700,000 year gap between these new Kenyan tools and those discovered in Ethiopia has led scientists to speculate that the knowledge of how to make the tools died out with the early human ancestors and then they were reinvented much later.
According to Harmand, the new discovery pinpoints an earlier starting point in our attempts to track human evolution.
"The Lomekwi 3 tools mark a new beginning to the known archaeological record," she said.
