56 The Morality of Nature 



begins to run about, shows at once the watching aptitudes 

 for which his race is admired. The young cat, before it 

 has seen an animal suitable for prey, will crouch and creep 

 in consummate practice of the style of attack of the natural 

 hunter. These things make heredity self evident. We may 

 simply know that the capacities are inherited by these 

 animals, because they do them easily, just in the way that 

 their parents did; while some other creatures cannot do 

 them until laboriously taught. 



These examples of heredity illustrate abilities which may 

 fairly be called recent when compared with other powers of 

 such animals. They are quoted first because their newness 

 shows cause and effect nearly connected. It may be noted 

 easily in regard to new habits, that they are evidently used 

 by the new generation for purposes discovered or invented 

 by some ancestor, who lived in the conditions which made 

 them useful. The chicken is a good example of recent 

 variation. It is one of a species of animals which generally 

 has the power of flight, and therefore is able and accustomed 

 to nest in trees, difficult of access to most enemies. But it 

 appears that when certain species of fowls under man's 

 protection nearly lost the power of flight by disuse, and 

 were compelled to nest in places accessible to snakes and 

 rats and such enemies, there was evidently a great dis- 

 advantage in the helplessness of slowly maturing nestlings. 

 The sooner they could stand and run the better their chance 

 of survival. In a nest of several fledglings those slow to 

 acquire this strength were often lost and those quickest 

 survived. Now these stronger running birds would produce 

 stronger running offspring because of the simple law of 



