POPULATION PROBLEMS 197 



birth has helped in the evolution of gentleness, pa- 

 tience, and affection. Other things equal, the more 

 maternal mother will have more children, thereby dif- 

 fusing her kindly gregarious temperament. But she 

 will also tend to give them more careful and successful 

 nurture. Thus, in two ways there will be a selection 

 of the more domesticated or more mammahan types. 

 This has probably meant much in man's evolution. 



Compared with fishes and amphibians, birds and 

 mammals are on the tack of economised reproductivity 

 and enhanced parental care. Compared with a Blue 

 Tit or a Common Wren, often with 8 eggs, the Guil- 

 lemot with only 1 shows the same economy ; it stakes 

 everything on one egg for the year, and yet it holds 

 its own well. Compared with rats and mice, highly 

 evolved mammals Hke bats and monkeys show great 

 reproductive economy, for they usually bring forth 

 only one offspring at a time. The important general 

 fact is that Man, however variable his fertihty in dif- 

 ferent races and in different sections of the commun- 

 ity, is on the evolutionary tack of economised repro- 

 ductivity and high parental care. It is an impor- 

 tant truth that everything became in some measure 

 new when Man became Man, but it is likewise of impor- 

 tance to understand that Man has simply developed 

 or elaborated a mode of evolution that is as old as many 

 of the hills. 



