The Origin and Evolution of the Genus Homo


 
 It is in Tanzania, Ethiopia, and South Africa that the earliest fossils of the genus Homo come.  They date from 1.9 to 1.6 million years ago.   The first fossil finds of this genus were of the species Homo habilis in the lowest level of the Olduvai Gorge.  This discovery was made by Louis Leakey and his co-workers.  The older specimens of the species bear a strong resemblance to Australopithecus africanus and the younger ones to show more in common with Homo erectus.

    The differences between Homo habilis and Australopithecus are:  homo habilis possesses a greater cranial capacity(610 to about 800cc), it has reduced prognathism- a flatter face and a shorter tooth row. Homo habilis has limbs still reminiscent of apes in terms of their relative proportions.  It is believed , therefore,  that Homo habilis was still a very good climber.

Here is the skull of Homo habilis.

 Homo habilis is also thought to have possessed a locomotion more human in attributes than that of  the australopithecines.  Stone tools and cut animal bones have been found associated with Homo habilis.  Brain specialists see in casts made from habilis skulls the bulge of Broca's area.  This bulge was not found in earlier hominids.  
 

This region is essential to speach; and so it is believed that habilis was probably equipped for rudimentary speach.  The giant increase in brain size made by habilis would have given the species the advantage of stone tool-making.  Tool-making also leads to the beginning of culture.  The best habilis material comes from Koobi Fora, on the east side of Lake Turkana in northern Kenya.