The gorge takes its name from the Maasai word oldupai which means’’ the place of the wild sisal’’. It was here that Mary and Louis Leakey discoveries of famous Zinjanthropus (Australopithecus boisei) skull, as well as remains of Homo habilis, the presumed maker of the numerous early stone tools found in deposits ranging in age from 1.6 to 1.8 million years ago, and Homo erectus, the larger- bodied and larger- brained hominin that preceded the earliest modern humans (Homo sapiens).