Skull of Paranthropus boisei, formerly called Zinjanthropus boisei then Australopithecus boisei. P. boisei was an early hominid, estimated to have lived 2.61.2 million years ago. The skull is specialised for heavy chewing and shows the species had a small brain capacity (about 500550 cubic cm, compared to about 1400 cubic cm for modern humans). This specimen, called OH 5 and nicknamed Nutcracker Man, was discovered in Olduvai Gorge, Tanzania in 1959. It is thought to be about 1.8 million years old.
