以下是引用zida在2003-12-28 16:44:00的发言:More than 2,600 sharp-edged flakes, flake fragments, and cores (cobbles from which flakes have been removed), found in the fine-grained sediments of a dry riverbed in the Afar region of Ethiopia, have been dated to between 2.52 and 2.60 million years ago, pushing back by more than 150,000 years the known date at which humans were making stone tools. FROM:
http://www.archaeology.org/9703/newsbriefs/tools.html