334 KEV. J. T. GTJLICK OK 



Social Selection tends toward divergent evolution of capacities 

 and of social organization. 



Filio-parental Selection is the exclusive breeding of those belter 

 adapted to the relations in which parents and offspring stand to 

 each other, througb the failure to live and propagate of those less 

 adapted. How the power of giving suck and the corresponding 

 instinct for sucking were first developed it may be impossible to 

 tell; but it is evident that having once been establislied as the 

 method of sustentation for the young of mammals, any young lack- 

 ing the instinct would perish without leaving descent. There is 

 every reason to believe that, with the exception of man, it may be 

 truly said of every individual mammal that all its ancestry, through 

 all its generations that have elapsed since they became fairly mam- 

 malian, have had this instinct in full force ; and yet it sometimes 

 fails, and the line of descent is cut short. Till comparatively recent 

 times the same was true of man; but we uow find some cases in 

 whicb the young survive in spite of their inability to suck, and 

 the constancy of this mammalian characteristic is being gradually 

 impaired. There is also in some races an increasing tendency to 

 shorter periods of lactation, or to the entire suppression of the 

 function ; so that it seems not improbable that there may yet 

 arise a variety of the human species in which the power will be 

 comparatively obsolete. Under such conditions the instinct for 

 sucking would cease to be of any advantage, while special advan- 

 tage would accrue to those best able to thrive on the artificial food 

 babitually provided by the parents. In some countries this 

 would be the milk of ruminating animals, while in other countries 

 it would be some vegetable preparation. In the islands of 

 Micronesia it is the sap that exudes from the cut end of the im- 

 mature fruit-stalk of the cocoa-nut tree. In Japan it is a sweet 

 extract of malt. Through this diversity in the food provided by 

 parents for their infants aiid small children, there is even now a 

 constant diversity in the Parental Selection prevailing in different 

 countries. Diversity in the forms of Parental Selection is also 

 produced by diversity in the clothing and artificial heat provided 

 by parents, in the protection, ou the one hand, of children from 

 the wind and rain and direct rays of the sun, and, on the other 

 hand, their exposure to the same with shaven lieads or naked 

 bodies, and in the methods of binding, cramping, and muti- 

 lating the head, feet, waist, and other parts of the body. Erom 



