THE CIVILIZATIONS OF MAN 91 



that led to man got under way. In this case it was the length- 

 ening of the pre- and postnatal period and the stretching of 

 the mating season to extend throughout the whole year. 

 More than anything else, this trend evolved the close, coop- 

 erative, and fuller family life of the great apes and man. The 

 much looser, usually only seasonal, family life of the birds 

 and mammals was gradually organized into a vastly impor- 

 tant, more or less permanent relationship— not just of the 

 "long suffering" mother and offspring, but a father-mother- 

 offspring relationship. Accompanying this trend toward 

 family life in the higher placental mammals was a greater 

 economy in reproduction: fewer and fewer young needing 

 more and more care if the species was to survive. The in- 

 creasing helplessness of the young which culminated in the 

 greatly lengthened postnatal period of the higher primates 

 finally brought the male into the picture. Wood-Jones 

 thought that the very great need of the helpless youngster 

 was enough to explain the final acceptance on the part of 

 the male of the paternal responsibility, but Weston La Barre 

 thinks it was due to the male's urges and needs for a sexual 

 outlet throughout the year. The male primate, La Barre 

 thinks, had undergone a long genetic selection toward a 

 permanent, nonseasonal sexual interest in the female because 

 reproduction in the tropics-dwelling primates had adapted 

 to the conditions of a plentiful year-round food supply and 

 uniformity of temperature. 



In any case and whatever the complex of obscure causa- 

 tive factors, the tremendously important institution of the 

 family appeared in the monkeys and apes long before the 

 advent of man. It is a wonderfully interlocking and progres- 

 sive institution. Increased dependency of the infant meant 

 increased nurture on the part of the mother and increased 

 protection of the two by the father; sexuality and sociability 

 were more closely interwoven; and all these relationships 

 give rise to greater bonds of mutual aid and teachability. It is 

 not surprising that the evolutionary rise of intelhgence in 



