Homo ergaster skull KNM-WT 15000 (1.6 million years).
The Homo ergaster Skull KNM-WT 15000 "Nariokotome Boy" or "Turkana Boy" was discovered by K. Kimeu in 1984 in Nariokotome, Kenya. It was first described by Brown, Harris, R. Leakey and Walker in Nature in 1985 as H. erectus. The completeness of this skull allowed scientists to get accurate measurements of brain size. Many other skeletal parts were also recovered, giving anthropologists a great deal of information regarding body size, limb proportions, age of death (probably 12 or 13 years) and whether or not language was possible. The pelvis reveals a greater ability to run than modern humans, and some reveal a closer affinity to australopithecines.