THE PROBLEM: THE MODE OF ITS SOLUTION 13 



transported thither from the neighboring continent. 

 But beetles are slow and clumsy fliers, and on these 

 wind-swept islands those which flew most would be 

 blown out to sea and drowned. Those which flew the 

 least, and these would include the individuals with 

 more poorly developed wings, would survive. There 

 would thus be a survival in every generation of a 

 larger proportion of those having the poorest wings, 

 and destruction of those whose wings were strong, or 

 whose habits most active. We have here a natural 

 selection which must in time produce a species with 

 rudimentary or aborted wings, just as surely as a hu- 

 man breeder, by artificial selection can produce such 

 an animal as a pug or a poodle. These, like sin, are a 

 human device ; nature should not be held responsible 

 for them. 



But you may urge that the variation which would 

 take place in a single generation would be, as a rule, 

 too slight to be of any practical value to the animal, 

 and could not be fostered by natural selection until 

 greatly enhanced by some other means. Let us think 

 a moment. If ten ordinary men run in a foot-race, the 

 two foremost may lead by several feet. But if the num- 

 ber of runners be continually increased the finish will 

 be ever closer until finally but an atom more wind or 

 muscle or pluck would make all the difference between 

 winning and losing the prize. 



Similarly the million or more young of any species 

 of insect in a given area may be said to run a race of 

 which the prize is life, and the losing of which means 

 literally death. The competition is inconceivably 

 severe. How indefinitely slight will be the difference 

 between the poorest of the 2,000 or 20,000 survivors 



