240 Naturalist at Large 



soon as the butterflies became sufficiently leaf-like to be 

 protected the evolution woiuld cease. It did no such thing. 

 The leaf butterflies of the Old World are decorated with 

 marks such as the fungi of decay produce on dead leaves, 

 and have ragged wing margins which look like wearings 

 or tearings in some cases. In other words, they have be- 

 come ridiculously and unnecessarily dead-leaf-like. Some- 

 thing pushed the evolutionary urge along far beyond ne- 

 cessity. 



Lamarck postulated the evolutionary power of use and 

 disuse and believed that acquired characters might be in- 

 herited. We all know, however, that certain sections of the 

 human race have mutilated themselves for thousands of 

 generations without result, and we know that in the old 

 days when horses' tails were regularly cut short, no short- 

 tailed colts ever appeared. 



As a matter of fact, to be realistic in our appreciation 

 of evolution we have to be willing to say, "I don't know 

 how or why, but it is there just the same." We have to 

 avoid believing in what may seem to be too obvious. Con- 

 sider how fearful the ordinary person is of inbreeding. 

 Such and such animals are inbred; hence they are weak, 

 stupid, deformed, or what have you. As a matter of fact, 

 animals may be successfully bred for countless generations, 

 brother to sister, if nothing but completely sound stock is 

 used to breed from. Of course one abnormal individual 

 may upset the strain and bad results will then appear, but 

 the bad results do not come from the inbreeding. 



I have recently been studying a group of fishing frogs, 

 deep-sea fishes in which the first element of the dorsal fin 

 has been developed into a fishing rod. In some of the fish 



