CHAPTER XI 



CONSANGUINEOUS MARRIAGES AND 

 MISCEGENATION 



" We are coming honestly to believe that the world is richer for the 

 existence both of other civilizations and of other racial types than our 

 own. . . . Even if we look at the future of the species as a matter of 

 pure biology, we are warned by men of science that it is not safe to 

 depend only on one family or one variety for the whole breeding-stock 

 of the world. For the moment we shrink from the interbreeding of 

 races, but we do so in spite of some conspicuous examples of successful 

 interbreeding in the past, and largely because of our complete ig- 

 norance of the conditions on which success depends." — Graham Wal- 

 las, Human Nature and Politics, pp. 293, 294. 



The peoples of the earth have followed the most varied customs 

 in regard to marriage. From extreme inbreeding we have all 

 gradations to the crossing of distinct races. Among savage and 

 barbarous peoples the practice of exogamy, or marriage outside 

 the tribe, is very prevalent. In general, we find that marriages 

 between near relatives are forbidden, and often the prohibition 

 goes farther and includes those bearing the same name or belong- 

 ing to a group which may be specified in various other ways. 

 Such prohibitions are not due to any instinctive repugnance to 

 incest, — certainly no such instinct occurs in the lower animals, — 

 nor is it reasonable to suppose, as has sometimes been done, that 

 they arose from the observed ill effects of consanguineous unions. 

 The effect of marriages among near kin is a matter about which 

 qualified students of genetics have come to different opinions, and 

 it is hardly probable that primitive peoples have been able to 

 arrive at valid conclusions on a subject that requires for its 

 solution a refinement of inductive method which is quite alien to 

 the thinking of untrained men. 



Among plants and animals the effects of inbreeding and cross 

 breeding have long attracted the attention of breeders. The 



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