THE CIVILIZATIONS OF MAN 93 



choanalyst. It is said that the objection to incest is purely 

 human, but there has been some claim that other animals 

 avoid it instinctively. In man the objection is a tradition and 

 not instinctive, as our social agency institutions and courts 

 of law can testify. 



Very likely, the next step in the evolution of human in- 

 stitutions arose when the young men of the family began to 

 bring home stray women, or the reverse, and probably less 

 frequent, situation when the young women brought home 

 stray men. Fringe individuals of both sexes are known 

 among the apes— individuals driven out of families by quar- 

 rels or crowded out by population pressure. A new young 

 woman in a family was protected from the Old Man by the 

 aggressive jealousy of the family females, who did not want 

 an additional rival, and by the courage possession had given 

 her mate. Probably, in the majority of cases, the Old Man 

 found it was just more than he could handle. In any event, 

 the successful grafting of a stranger to the group, or exog- 

 amy, gradually came into existence. Exogamy is marriage 

 by taking a strange mate from outside the tribe, and there 

 are world-wide traces of this custom in primitive peoples. 

 Out of it, say the anthropologists, arose the taboos against 

 intercourse between mother-in-law and son-in-law and be- 

 tween father-in-law and daughter-in-law. There are fossil 

 reminders of exogamy in the marriage ceremonies of to- 

 day, where age-old marriage customs introduce primor- 

 dial taboos to protect the bride. The disturbance and excite- 

 ment of a strange female in the family is dampened down 

 below the level of social disruption. Among the Siberian 

 Ostyaks the bride must not appear before her father-in-law 

 nor the husband before the mother-in-law until they have 

 children, and the bride must cover her face against her 

 father-in-law throughout life. The in-law taboo is very 

 widely spread and takes strange twists. A Zulu in Africa 

 hides his face with his shield if he meets his mother-in-law, 

 or throws away a mouthful of food if she passes by while he 



