Rock-solid choices of first toolmakers

From Montreal, at a joint meeting of the Paleoanthropology Society and the Society for American Archaeology

At the dawn of stone-tool production around 2.6 million years ago, our human ancestors already showed considerable insight into the task at hand. They worked mainly with rocks that they had carefully picked as suitable for being fashioned into sharp-edged implements, says Dietrich Stout of Indiana University in Bloomington.