A U. of Calgary archaeologist has found the first prehistoric evidence of chimpanzee technology, adding credence to the theory that some of humanity's behavioural hallmarks were actually inherited by both humans and great apes from a common ancestor.From the press release:
Dr. Julio Mercader uncovered stone 'hammers' last year in the Taï rainforest of Africa's Côte D'Ivoire (Ivory Coast) that date back 4,300 years.
"It's not clear whether we hominins invented this kind of stone technology, or whether both humans and the great apes inherited it from a common forebear," says Mercader. "There weren't any farmers living in this region 4,300 years ago, so it is unlikely that chimpanzees picked it up by imitating villagers, like some scientists used to claim."
The stone hammers that the team discovered, essentially irregularly shaped rocks about the size of cantaloupes -- with distinctive patterns of wear -- were used to crack the shells of nuts. The research demonstrates conclusively that the artifacts couldn't have been the result of natural erosion or used by humans. The stones are too large for humans to use easily and they also have the starch residue from several nuts known to be staples in the chimpanzee diet, but not the human diet.
More info and photo from here.