Masterpieces of Science 



innovation. But why this should be a law of 

 nature if each species has been independently 

 created no man can explain. 



Many other facts are, as it seems to me, expli- 

 cable on this theory. How strange it is that a 

 bird, under the form of a woodpecker, should 

 prey on insects on the ground; that upland geese 

 which rarely or never swim, would possess webbed 

 feet; that a thrush-like bird should dive and feed 

 on sub-aquatic insects; and that a petrel should 

 have the habits and structure fitting it for the 

 life of an auk ! and so in endless other cases. But 

 on the view of each species constantly trying to 

 increase in number, with natural selection always 

 ready to adapt the slowly varying descendants 

 of each to any unoccupied or ill-occupied place 

 in nature, these facts cease to be strange, or 

 might even have been anticipated. 



"We can to a certain extent understand how it 

 is that there is so much beauty throughout 

 nature; for this may be largely attributed to the 

 agency of selection. That beauty, according to 

 our sense of it, is not universal, must be admitted 

 by every one who will look at some venomous 

 snakes, at some fishes, and at certain hideous bats 

 with a distorted resemblance to the human face. 

 Sexual selection has given the most brilliant 

 colours, elegant patterns, and other ornaments 

 to the males, and sometimes to both sexes of 

 many birds, butterflies and other animals. "With 

 birds it has often rendered the voice of the male 

 musical to the female, as well as to our ears. 

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