Paleoarchaeologists working in Kenya have unearthed the oldest known stone tools found to date, and say that they predate our earliest known ancestors by over half a million years.
Digging by accident at a site they didn’t originally intend to visit, Sonia Harmand and Jason Lewis of Stony Brook University in New York, found stone tools that they’ve dated to 3.3 million years ago, 700,000 years older than previously found artifacts. Anthropology professor Alison Brooks, George Washington University, has examined some of the tools. "It really absolutely moves the beginnings of human technology back into a much more distant past, and a much different kind of ancestor than we’ve been thinking of."
The size of the tools is also puzzling scientists, in that they are much larger than next oldest known artifacts, with some of the stone flakes being eight inches long, and the core pieces that they were struck from being nearly seven pounds. What sort of primate might have been able to handle stones that large and have the intelligence to do so remains unknown.
There is also the puzzle of who made the tools in the first place, and scientists are not ruling out non-human hominins as candidates, including Australopithecus afarensis, better known as the fossil of the individual nicknamed "Lucy". Professor Nick Toth, Indiana University, says that the find resembles the product of his experiments in teaching chimpanzees to make their own stone tools. "You don’t need a very large brain … to understand the basic principles of fracturing stone."