It is now clear that tools antedate man, and that their use by prehuman primates gave rise to Homo sapiens Presenting a series of articles on the human species, with special reference to its origins.

Early stone toolmaking marks an important juncture in evolution. The Oldowan stone tools from Hadar, Ethiopia, are among the oldest known, dating back 2.3 million years. Shown from various angles ...

These dates are only approximate, as the tools have been dated from the environments they were found in. This is often the layer of sediment that surrounds the tool. Dating can be done by ...