Ancient hands were skilled but whose?
Stone tools made in Kenya almost 2.5 million years ago reveal that the first toolmakers in the archaeological record had a hitherto unrecognized degree of technical skill - but there is no indication of whether the toolmakers were human.
Reporting in the May 6 issue of the science magazine Nature, Hélène Roche of the CNRS (Centre Nationale de la Recherche Scientifique) Préhistoire et Technologie unit in Nanterre, France, and colleagues describe stone tools from an archaeological site called Lokalalei 2C, close to the western shore of Lake Turkana in northern Kenya. The site has been dated at 2.34 million years old. The oldest known stone tools from anywhere are 3.5 million years old, and come from Ethiopia.
The researchers recovered nearly 3,000 stone-tool fragments scattered over an area of 17 sq. meters. This site represented a single occupation surface, and turned out to be a kind of stone tool factory. The makers made the tools on this very spot. Ten percent of the fragments fit onto other fragments, and it was possible to match 60 sets of complementary stone artifacts. This means that the researchers were able to match the flakes to the stone cores whence they were struck - in one instance, up to 20 flakes on a single cobble.
This careful work, involving the painstaking refitting of small stone chips, gives an insight into the minds of the earliest toolmakers. The research reveals the order in which flakes were struck from a core. Flakes appear to have been struck in preferred directions in rapid succession, implying a degree of knowledge of the material, dexterity in handling, and possibly a distinct purpose. Although these tools do not have the exquisite sophistication of the familiar "hand axes" (found in sediments younger than 2 million years), they are far from being randomly chipped rocks created by shambling yahoos. Roche and colleagues provide evidence, for the first time in the archaeological record, of minds at work.
But whose minds?
Around 2.5 million years ago, several distinct hominids (species of the human family) lived in East Africa. Paranthropus boisei, often dismissed as a brutish ape-man, could have had the manual dexterity to shape tools. Its contemporaries Homo habilis and Homo rudolfensis, however, are usually assumed to have been the toolmakers, but recent work has cast doubt on whether these species are really any more humanlike than Paranthropus, or the assemblage of primitive, generalized hominids called australopithecines.
Another of these, Australopithecus garhi, discovered in Ethiopia by Tim White of the University of California Berkeley and colleagues and announced April 23 in Science magazine, only broadens the list of suspects.
MAN THE TOOLMAKER - French archaeologist Hélène Roche shows off a stone chipped into some 20 flakes by very early hominids 2.34 million years ago. AP PHOTO