Oldupai Gorge is one of the most significant prehistoric sites on the planet and has been instrumental in furthering the understanding of early human evolution. Oldupai has yielded numerous fossil remains from Pliocene to Pleistocene times (about 5 million to 10,000 years ago). One of the findings was a skull of the primitive hominid Australopithecus boisei, or nutcracker man, a species that became extinct about one million years ago.
Despite the controversy surrounding the interpretation of many of the Oldupai specimens, scientists agree that no other site has produced stone tools, animal bones and early hominid remains so precisely associated in such a well understood environment. The 3.75 million year old fossilised footprints, found by Dr. Mary Leakey in 1975 at nearby laetoli, proved that our prehuman ancestors walked in a upright position, this is widely thought to rank among the greatest palaeoanthropogical discoveries of the past century.