THE HISTORY OF THE PRIMATES 



Figure 65. Mandible of 

 Oreopitheciis bambolii. 

 ( From Hiirzeler, Verh. 

 Naturf. Ges., Basel, V. 69, 

 1958. ) 



and limb bones. In 1958, a nearly complete skeleton was recovered, but 

 its thorough study is still in the future. The dental formula is the typical 

 anthropoid 2-1-2-3, and the proportions of the teeth tend to ally them to 

 man rather than to the great apes. Unlike the apes, there is no diastema 

 between the canines and the premolars. The details of the molars and of 

 patterns of wear also tend to ally them with man. The limb bones and 

 vertebrae have been studied less completely, but they too seem to support 

 the conclusion that Oreopitheciis was hominid. Hiirzeler considers that 

 the hominid trends of this animal were sufficiently advanced that they 

 must have been in progress for a considerable time, and hence that the 

 separation of the earliest hominids from primitive anthropoids must be 

 sought even earlier than the Miocene. Yet it is possible that Oreopitheciis 

 represents a new family, allied to the Hominidae, but distinct from it. 



The Australopithecines. Most of the later hominoid fossils can be 

 clearly assigned either to the genus Homo or to the anthropoid apes, but 

 one important group of fossils which has been discovered in South Africa 

 is controversial in this respect. The original find was made in 1925 at 

 Taungs by R. Dart, and described by him under the name of Australo- 

 pithecus ( southern ape ) . This was the skull of a child of about six years, 

 and it showed a curious mixture of human and simian characters. The 

 difficulties of study in this case were increased by the fact that most com- 

 parisons are based upon adult specimens. But a considerable number of 

 additional skeletons, some nearly complete, have since been found by 

 Broom, Dart, and others. Three genera have now been described, but all 

 are included in a single subfamily of the Hominidae, the Australopithe- 



cmae. 



The skull of the australopithecines resembles that of a modem chimpan- 

 zee, but the differences are significant. First, the brain case is larger in the 

 fossil, having a capacity of about 600 cubic centimeters. This is somewhat 

 larger than that of the gorilla, but is much larger compared to body size 

 (about four feet tall). The forehead is more rounded out than in the 

 chimpanzee, possibly indicating greater development of the highest cen- 

 ters of the brain. The eyebrow ridges are very prominent, but less so than 

 in the chimpanzee. The jaws protrude quite prominently, but again less 

 so than in the modern ape ( Figure 66 ) . The dentition is quite human in 



185 



