This fourth volume marks the definitive publication of the most important fossil finds in palaeoanthropology: Olduvai hominids 7. 13, 16 and 24 (popularly known to workers in the field as Jonny's Child, Cindy, George and Twiggy). Found from 1960 in Olduvai Gorge and dating from 1.9 to 1.6 million years ago, they were identified in 1964 by Louis Leakey and the author amidst great controversy as a hitherto unrecognised species of the genus Homo, named by then Homo habilis on account of its apparent tool-making abilities. Professor Tobias develops this conclusion through extensive analysis of the cranial and endocranial material and teeth and comparison with a treasury of data, much of its original, on early hominds from South and East Africa, Asia and Europe, as well as modern human and anthropoid ape specimens. He offers a substantial exploration of the place of Homo habilis in human evolution, its status in relation to the australopithecines and Homo erectus and its apparent capacity for spoken language, which he sees as the key to the staggering enlargement of the human brain over the last two million years.

Foreword by: Raymond A. Dart