HUMAN ORGANIC EVOLUTION: FACT OR FANCY? 



most recent addition, not independent of the environment, 

 but capable of changing it to suit himself to a degree that no 

 other animal is capable of, and his productive efficiency is 

 higher than in other animals, especially through postnatal 

 care. He points out, that a fundamental difference lies in the 

 fact that man is not dependent for survival on inherited 

 characteristics, but through the process of learning,26 con- 

 ceptualization, and social organization can transmit acquired 

 traits to his offspring thereby short-circuiting the slow genetic 

 mechanisms of lower animals through the mechanisms of 

 adjustment provided by what anthropologists call culture. 



Thus even from a naturalist's point of view the gap betw^een 

 the animals and man is still not bridged in spite of much work 

 of an experimental nature that has been carried on with higher 

 primates. Twenty-four years ago Father Cooper^^ said in 

 his excellent paper on the evolution of man that the gap 

 between mental development of man and that of the apes is 

 too great to be bridged. Though he did not rule out the 

 possibility of mental evolution, the evidence seemed too 

 negative at that time to warrant such considerations. Eisely^s 

 reviewed the literature on just this problem twenty-three 

 years later and notes that "The gap between man and ape 

 is not as the early Darwinians saw it — a slight step between 

 a gorilla and a Papuan, or a chimpanzee and a gibbering 

 Hottentot. Instead, it stretches broad and deep as time itself." 

 He also points out that in spite of much work in which he 

 collaborated, the interpretation of psychological evolution is 

 highly speculative, because the critical moment when primates 

 came out of the trees is perhaps least understood in regard to 

 the forces that produced this change. Even for the Austra- 

 lopithecus it has not yet been established whether they were 

 hunters or the hunted. One thing seems to emerge, however, 

 that with the displacement of dependence on inherited adaptive 

 mechanisms by the culture-building brain a tremendous change 

 took place. How this came about, anthropology cannot answer 



26 Cf. Simpson, op. cit., pp. 284—287. 

 2T Op. cit. 



'^^ Loren C. Eiseley, "Fossil Man and Evolution," Current Anthropology 

 (W. L. Thomas, Jr., ed.), 1956, pp. 61-78. 



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