THE STRUGGLE FOR EXISTENCE 115 



will represent at least 500 grains of wheat, the rice 

 pudding at least 1000 grains of rice, not to speak of 

 a couple of eggs required as an ingredient. In addi- 

 tion we have, say, 100 seeds of mustard and ten fruits 

 of pepper. Here, then, to start with, we have 1828 

 lives sacrificed. But to these we must add millions 

 of yeast cells, required in the manufacture of the 

 bread, millions of Bacteria required for the matura- 

 tion of the cheese and wine, together with thousands 

 of seeds of the vine, destroyed in the production of 

 the wine. We need not pursue the illustration further, 

 for when we begin to consider that not only is man 

 slaying his thousands of lives at every meal, but that 

 every herbivorous animal is slaughtering plants all 

 day long, and every carnivorous one, animals, when- 

 ever it can get the chance, we need have no diffi- 

 culty in understanding how it is that, notwithstanding 

 its enormous powers of increase, no organism ever 

 succeeds in entirely dominating the earth. 



It will thus be seen that relatively only a few of 

 each generation survive and propagate in turn. 

 There must be a continuous and intense, though in 

 most cases unconscious, struggle for existence taking 

 place among organisms, and this struggle will be struggle 

 keenest amongst those most closely related, since existence, 

 obviously these forms will be desirous of the same 

 location, the same environment, the same articles 

 of food, and will endeavour to protect themselves 

 from the same kind of enemy or vicissitude of climate. 

 Again, the struggle will be keenest among the young, 

 since every organism is most liable to injury in the 

 young stages of development, that being the most 

 critical period in its life-history. We must now ask 

 ourselves what conditions determine which of the 

 organisms shall survive and which shall succumb ? 



