mentary hunting. That is, the initial kick can be described as a slight devia- 

 tion of the system from a condition of omnivorous food-gathering without 

 tools or with only sporadic use of tools toward another condition, that of 

 hunting and gathering with the systematic aid of unmodified tools. Maybe 

 a single jump— or kick— to hunting is too great; the shift to scavenging, 

 I should suggest, might be a more probable part of the first step. All 

 the other features of hominization. as listed, could be interpreted as direct 

 or indirect consequences of that initial "double-push." Thus, the direction 

 of further evolution was determined at the very beginning of the whole 

 process. The behavior of the whole system was characterized by a high de- 

 gree of determination and predictability (Bielicki 1969). 



A corollary, Bielicki points out, is that hominization is, in principle, a 

 repeatable event. All that was needed was for the same initial kick to have 

 occurred in several different species of higher catarrhines with similar struc- 

 tural and functional potentialities for tool-using and hunting (or scaveng- 

 ing). Thus, the early tool-using bipedal hominids postulated by Simons, 

 Pilbeam, and Leakey to have existed in Mio-Pliocene times need not have 

 been ancestral to the Pleistocene tool-users at all. 



Another suggestion of Bielicki is that the process of hominization, once 

 started, would soon have acquired a relatively high degree of independence 

 of the stresses of the external environment, since it was not the external 

 environment but cultural behavior that provided the main source of selec- 

 tive pressures on the population's genotype. One can therefore speculate, says 

 Bielicki, that the whole process would not have stopped, and would have 

 followed a fairly similar course, even in a completely static environment: 



This seems to be a rather peculiar mode of evolution, different in certain respects 

 from the standard situation in which the main driving force of long-term direc- 

 tional evolution of a species is a series of selective responses of the gene pool to 

 the changing factors of the physical and biotic environment. 



The above interpretation, however, has of course nothing to do with the 

 concept of orthogenesis, since it does assume adaptation through natural selection 

 as the principal agency responsible for the hominid evolutionary progression. 

 [Bielicki 1969, p. 59] 



Bielicki here seems to contradict himself. I shall return to this point below. 



Another corollary, Bielicki believes, is that possibilities for extensive 

 adaptive radiations with speciation within the hominid line can be presumed 

 to have been very small. 



Finally, he suggests that the hominization of the postcranial skeleton 



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