ANNE MCILROY
SCIENCE REPORTER
Chimpanzees had their own prehistoric Stone Age, a Canadian archeologist has found, and were using rocks to open nuts 4,300 years ago.The primitive nut crackers found in the Ivory Coast rain forest challenge the widely held belief that early humans invented stone tools, University of Calgary researcher Julio Mercader and his colleagues say. It may have been a common ancestor to both humans and chimps that first started bashing nuts with rocks.
4,300-year old rocks were found with patterns of wear and traces of ancient nut starch on them. Proof, Dr.Mercader says, that the ancient chimps were using the technology. They were similar to the kinds of nut-cracking rocks the modern chimps use.
At that time humans had not settled in the region, the scientists say. When people did start farming in the area, they ate different kinds of nuts than the ones found on the stone tool.
This means, Dr.Mercader says, that chimps had their own Stone Age that started at least 4,300 years ago and possibly much earlyer. West african chimps may have passed the skill on for more than 200 generations, he says.
From the Globe and Mail,
February 13, 2007
