KNM-ER 3733, Homo erectus Discovered by Bernard Ngeneo in 1975 at Koobi Fora in Kenya. Estimated age is 1.7 million years. This superb find consisted of an almost complete cranium. The brain size is about 850 cc, and the whole skull is similar to some of the Peking Man fossils. The discovery of this fossil in the same stratum as ER 406
(A. boisei) delivered the coup de grace to the single species hypothesis: the idea that there has never been more than one hominid species at any point in history. (Leakey and Walker, 1976) This is one of the more complete cranium recovered from the Koobi Fora region. This has been assigned to Homo Erectus. It shows marked differences with Asian Homo Erectus specimens. It is similar in overall size to those from Zhoukoudian in China however. The cranial capacity has been recorded at 848 ml. Wear on the teeth suggest that this was an adult individual. KNM-ER 3733 was found above the KBS tuff.
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