200 Changing Human Nature 



Africa (Fig. 50). If we go from the oldest of these fossils 

 to the more recent we find that there has been a progressive 

 change in the skull involving an elevation of the forehead 

 and a reduction of the brow ridges. With these has gone 

 an enlarged brain (the fossils show of course only the brain- 

 case or cranium) , and especially an enlargement of that por- 

 tion of the brain which is related to the higher mental proc- 

 esses and to speech (see Fig. 51) . The following table gives 

 the average brain capacity of a series of human types between 

 these extremes. It should be noted that in many cases the 

 number of samples from which the average is taken is very 

 small and in a few cases only one. 



Brain Capacity (After Osborn 1927) 



Pithecanthropus erectus 940 cc. 



Indian Veddahs 1000 cc. 



Piltdown of Sussex 1070 cc. 



Average Modern Swiss 1200 cc. 



Living Broadhead Czecho-Slovakian 1230 cc. 



Papuans, New Guinea 1236 cc. 



Native AustraUan 13 10 cc. 



Upper Paleohthic Broadhead 1400 cc. 



Average Modern European 1450 cc. 



Cro-Magnon 1550 cc. 



'Pre-hufnan Origins 



The stock of primates from which Homo probably de- 

 scended is unlike any of the present-day apes. It has been 

 impossible, however, for paleontologists and anthropologists 

 to agree upon one of the fossil types as the probable common 

 ancestor of man and the anthropoids. The difficulty is due 

 entirely to the absence of adequate fossil records. In recent 

 years there have been found both in Egypt and in India 

 jaws and teeth of several genera that are on the one hand 

 more primitive than the earliest apes, but that show, on the 

 other hand, definite indications of human traits, especially 



