MAN AND MANKIND 



evolution. The outstanding individual, that is the individual havinc; 

 an outstanding reaction with his environment, is exceedingly impor- 

 tant in human history even though his emergence can be roughly 

 predicted from the flexibility of the mass. The adaptations and 

 fluctuations are, in turn, responsible for the increasing tempo of human 

 change and the increasing contrasts of genetic capacity for culture 

 between different genetic groups. 



General propositions concerning the genetic bases of culture need 

 to be stated first, but for a practical and specific example we can 

 as yet foreshadow their probable effects only in one field, that of 

 language. 



The rapid development of language from emotional cries, postu- 

 lated by Darwin, is the outstanding example of the self-propagating 

 or cumulative properties of human culture. We have already seen 

 that races of man largely depend on the barriers of language for 

 their maintenance. We must note also that the recognition of the 

 unity of the Aryan languages by Sir William Jones in 1784 was one 

 of the mainsprings of evolutionary theory (as well as of racial 

 superstition) to which genetics owes so much. It is a debt which 

 genetics can now begin to repay. 



The existence of a genetic component or racial basis for culture 

 has long been obvious enough to have been worth denying. The 

 genetic component of language, on the other hand, has been assumed 

 with very little controversy to be either everything in it, or nothing 

 at all. Let us consider the evidence. 



The precise genetic control which we now know to exist over 

 the development of all bodily structures, as we can see from the 

 strength of racial and family resemblances, extends, as Duckworth 

 and others have shown in great detail, to the organs of speech. This 

 genetic control must limit, not so much the ability, as the ease with 

 which races and individuals are capable of uttering the various 

 sounds within the range of the human voice. 



Certain racial, family, and individual differences in tongue shape 

 and tongue movement are so sharp as to be obviously hereditary. 

 Their racial significance was first noted in the division of the Jews 

 according to those w^io could, and those, numbering 42,000, who 

 "could not frame to pronounce" the word "shibboleth" right 

 (Judges 12: 4-6). The widely differing command that individuals 



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