DARWINISM. 209 



but always presents some points of difference. This 

 claim has been abundantly proved and universally 

 acknowledged, both in regard to domestic varieties 

 and animals under nature. (2) Darwin emphasizes 

 the old idea that animals and plants multiply with 

 much greater rapidity than the food upon which 

 they live. Many more animals are born than can 

 possibly succeed in reaching maturity. A single 

 codfish, for instance, produces some 9,000,000 eggs 

 in a season ; and if all reached the adult state and 

 reproduced in like manner, a very short time would 

 serve to fill the ocean completely with codfish. A 

 vast majority of the animals which are brought into 

 the world must therefore be killed before reaching 

 the adult stage. Owing to this constant over-pro- 

 duction of young in every species, all animals are 

 in a contest with each other, either directly or in- 

 directly, for the food which is to be had. Every 

 individual is, therefore, constantly engaged in a 

 struggle for existence, and if he be weak and unable 

 to contend with others, he will succumb in the 

 struggle and die before reaching a condition to 

 reproduce. (3) This struggle for existence is con- 

 stantly affecting all animals, and it is evident that 

 it is only the stronger individuals, or those especially 

 favored by some advantage, which will come off 

 victors in this struggle, and reach maturity so that 

 they can leave offspring. If some individual has 

 an advantage over others, it is plain that it would 

 survive and leave offspring. If, therefore, in the 

 infinite variations which are presented by all ani- 

 mals, as shown above, any individual chance to pos- 



