At CRAFT (Center for Research into the Anthropological Foundations of Technology), researchers are exploring the role technology played in human evolution by trying to determine what early stone tools were used for and how they were made. In this stop-action photograph, a split second after impact, a hammerstone detaches razor-sharp flakes from a stone core. These flakes can then be used as tools to slit through the hides of dead animals and cut meat from bones, a "cutting-edge" idea that helped our ancestors dramatically improve the quality of their diet.