CHAPTER XII. 



Natural Selection (continued) — Curtailment of the Number of Births in a 

 Community hinders Evolution and favours Dissolution. 



In the last chapter, while considering communities whose 

 population does not increase, we had occasion to notice that 

 this stationary condition of the population might be due to two 

 causes : either to active weeding out, as in savage communities, 

 or to limitation in the number of births, as in France, for 

 instance, and I said that, whenever the number of births is 

 thus curtailed, the health of the community must suffer, evolu- 

 tion being hindered. We will now briefly inquire into this 

 statement. 



In a large family, inasmuch as it is impossible to get 

 equality, some of the children will certainly be more vigorous 

 than others; and some one must be the strongest and most 

 vigorous. Now, if the number of children which any one 

 couple is capable of rearing be curtailed, and especially if it 

 be limited to so small a number as three or four, the chances 

 are against the potentially strongest individual being born, 

 and so the nation is deprived of those who might have been 

 its best children. Other things being equal, the most prolific 

 nation has the best chance of physical improvement and the 

 least chance of degeneration. 



In reference to this tendency of any artificial check to 

 population, it would be interesting to inquire at what particular 

 period in the lives of the two parents the reproductive power 

 is at its prime — i.e., at what age the capacity of producing the 

 best offspring exists ? In France the father is often past 

 middle life ; and although this has its advantages, yet there 

 can be little doubt that in the male the procreative power is 

 at its prime before middle life. Late marriages on the part 

 of the. man are certainly not altogether favourable to racial 



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