THE INTEGRATION OF THE SEXES — MARRIAGE 279 



should encourage caution in dealing with the statements 

 found in ethnographic Hterature. One of the arguments 

 against polygyny is that it tends to reduce the birth rate, 

 but studies in native Africa and elsewhere suggest that 

 when economic and social conditions are similar, the birth 

 rate for monogamous marriages is the same as for polygy- 

 nous. In this respect, then, monogamy and polygyny are 

 upon the same level. The case for polyandry is not so good, 

 but there is still reason for doubting that the birth rate is 

 seriously impaired by this form of marriage; for one thing, 

 it seems to have existed in certain parts of the world for a 

 long time. 



On the other hand, promiscuity is under suspicion. It is 

 generally beheved that the few females in modern society 

 who are promiscuous are rarely mothers. In many primitive 

 populations a period of promiscuity precedes marriage and 

 it is the behef of observers that pregnancies are rare during 

 this interval. This imphes that in a state of promiscuity, the 

 birth rate will be near the vanishing point. Yet, too great 

 weight should not be given this evidence, because such 

 approximate sterihty seems to result from intense sexual 

 activity, stimulated by special conditions, whereas advancing 

 age and preoccupation with the affairs of life might be 

 expected to ehminate excessive unions and so approximate 

 the normal conditions favoring reproduction. Prostitution 

 is not pecuhar to modern monogamous society, but occurs 

 regardless of the form of marriage. Even in primitive com- 

 munities prostitutes are to be found. The number of women 

 so engaged is always small and though this number may 

 rise and fall with the changing social complex of the group, 

 it rarely rises above a negligible minority, and so cannot 

 materially affect the birth rate as a whole. If then, a condition 

 of absolute promiscuity should prevail, there is some reason 

 to expect a lowered birth rate, which in turn might militate 

 against promiscuity in favor of marriage. Also, there is 

 some reason to believe that promiscuity would be incom- 

 patible with stable group life and would materially interfere 

 with the proper care of children. So, on the whole, it seems a 

 justifiable conclusion that there are biological obstacles to 

 general promiscuity in favor of unions of reasonable stability 



