88 The Morality of Nature 



food is scarce and when hunting animals, including man, are 

 hungry for meat, the young, and sometimes the old, die in 

 numbers. Yet we see readily that the death of the weak is 

 likely to happen first, and the survivors will be those best 

 able to continue the race under the same circumstances. So 

 that in this class of animal life is found a proj ortion of death 

 to population which is lessened by the improvement in con- 

 duct, and which is coming distinctly nearer to our conception 

 of an award justly adapted to conduct. There is apparently 

 in the balance of the factors, much more effect due to the 

 growing power to prevent death, and to reduce thereby the 

 need for a production by birth of excessive numbers. There 

 appears, however, a limit to these benefits of prevention, and 

 death is seen to be still a necessary process. If the upward 

 improvement is to go on, there must be a weeding out, so that 

 these left are, in ability, not an average of those born, but a 

 higher selection of them. In this the race meets and provides 

 for new conditions as they appear, and the new conditions 

 always beget competition in ability. The qualities inherited 

 as acquired by ancestors under their circumstances are not 

 specially adapted for the present new circumstances. These 

 must be met by new abilities. They are regarded and de- 

 veloped by the favoring of such variations as prove bene- 

 ficial, and the rejection of such as have not the beneficial 

 trait. Since these creatures have no power to reason about 

 the future, they must retain the method of experimental trial, 

 and therefore the retention of a habit of variation is 

 necessary. 



The deer in a forest vary in regard to their love of 

 locality, some may have a very small range and a great 



