PENINJ MANDIBLE

also called Natron Mandible, an almost perfectly preserved fossil hominid jaw containing a complete set of adult teeth. It was found by Kamaya Kimeu at Peninj, a locale to the west of Lake Natron, about 50 miles (80 km) from the Olduvai Gorge in Tanzania in 1964. About 120 artifacts belonging to the Acheulian industry, including stone cleavers and hand axes, were also unearthed near the fossil. The sandstone in which the fossil was found has been dated to about 1,500,000 years ago. The artifacts came from a somewhat later period. The mandible is robust and deep with tiny incisors and canines and larger premolars and molars. Only one tooth was damaged, though the rest were heavily worn. The specimen was assigned to Australopithecus boisei.