the cultural components. These feedbacks were in each case positive, that 

 is, deviation-reinforcing rather than horneostatic. This is the crucial point 

 stemming from Maruyama's theory. 



For example, the interrelationship between the element "brain-size" 

 A, and the element "complexity of implemental behavior," B, can be postu- 

 lated to have been such that any progress in A must inevitably have led to 

 some progress in B (because a shift of the frequency distribution of A "more 

 to the right" would produce within the population a new extreme class of 

 "supranormal" segregants who would, sooner or later, put to use their "ex- 

 tra capacities" and further enrich the existing technology). Contrariwise, 

 any progress in B must have generated (by raising the proportion of "below- 

 threshold" individuals in the population) selective pressures that, in turn, 

 forced A to continue its development in the same direction as before. 

 The 2 elements were bound to evolve together, in a parallel fashion, mu- 

 tually stimulating one another. 



Bielicki postulates the existence of such closed loops of positive feed- 

 backs, sometimes in pairs, sometimes in triplets. Other combinations he 

 considers are ontogenetic retardation-tool-making and erect bipedalism— 

 tool-making— hunting. He thus attempts to conceive the whole process of 

 hominization in terms of such deviation-amplifying or "morphogenetic" 

 systems. Such systems exhibit certain properties that seem noteworthy to 

 students of human evolution. For example, such a system is set in motion 

 by an "initial kick," as stressed, too, by Holloway (1967), often small in 

 extent and statistically, therefore, not at all improbable. Once initiated, the 

 system would gradually and spontaneously build up deviations and diverge 

 from the initial condition. Given enough time, a development can ensue 

 that is disproportionately large as compared with the force of the initial 

 push. 



In other words, 



. . . an insignificant, and therefore quite probable, deviation from a certain 

 initial, static condition can, through the mutual amplification of deviations, 

 finally result in a very considerable deviation which otherwise (i.e. without the 

 existence of positive feedback circuits within the system) would have a very small 

 probability of occurrence. [Bielicki 1969, p. 58] 



Applying these ideas more specifically to human evolution, Bielicki 

 suggests that the initial push may have been the emergence, in some species 

 of Pliocene semiterrestrial pongids, of systematic tool-using and of rudi- 



145 & 



