 In 1994 while searching through museum boxes labelled 'Cercopithecoids' containing fossil fragments, Ronald J. Clarke identified several that were unmistakably hominin.He spotted four left foot bones (the talus, navicular, medial cuneiform and first metatarsal) that were most likely from the same individual.These fragments came from the Silberberg Grotto, a large cavern within the Sterkfontein cave system.