12 DARWINISM AND HUMAN LIFE 



Tennyson's " In Memoriam," which was written 

 before " The Origin of Species." The poet speaks 

 of Nature " red in tooth and claw with ravine " ; 

 " so careless of the single life " ; " of fifty," or 

 (as he afterwards suggested) " of myriad seeds 

 she often brings but one to bear." But it is certain 

 that no one before Darwin realised the length 

 and breadth, the height and depth, of the struggle 

 for existence. His realisation of it is " bigger " 

 than that of most of his successors. Darwin 

 recognised the struggle between Fellows, the 

 struggle between Foes, and the struggle be- 

 tween Living Creatures and the Physical Forces. 

 (a) There is cannibalism in the cradle in the 

 egg-capsules of the buckie and the dog-whelk ; 

 locust may eat locust when the worst comes to 

 the worst ; stag may fight to the death with 

 stag in the forest clearing ; certain mountain- 

 varieties of sheep will starve out other mountain- 

 varieties ; the sister seedlings compete together 

 in the plot : that is Struggle between Fellows. We 

 may extend this category of competition between 

 individuals of the same species to include com- 

 petition between individuals of nearly related 

 species, though what is involved in the step should 

 be carefully noticed. If we make the e:ctension, 

 however, we include Darwin's well-known case 

 of brown rat versus black rat. The other illus- 

 trations he gave concerned two kinds of thrush, 

 two kinds of swallow, two kinds of cockroach, and 

 two kinds of charlock, (b) Secondly, the world 

 is full of competition and struggle between living 

 creatures not nearly related to one another — 

 between fox and hare, between stoat and rabbit, 

 between mongoose and snake, and so on, end- 



