50 ODD HOURS WITH NATURE 



white cats with blue eyes, which are always deaf. 

 It seems impossible for a white cat to acquire 

 blue eyes without at the same time losing its 

 power of hearing. To put the matter in the form 

 of a proposition : the patent modification may 

 be only the outward and visible sign of some 

 invisible grace or defect, which grace or defect 

 tells in survival and not the thing that meets the 

 eye. 



In the case of the two sparrows it is perfectly 

 safe to say that the thing that counts is not the 

 slight difference in plumage, but a psychological 

 difference which may or may not be related to 

 it. And here it is too readily taken for granted 

 that we have a case of a remarkable success in life 

 the house-sparrow, and a comparative failure 

 the tree-sparrow. Despite its obviousness the 

 assertion may be challenged. In a good natural 

 history sense the tree -sparrow, a perfectly respect- 

 able finch, is an honester and more stable success 

 in life than its squalid relative. To begin with, 

 the species has proved its adaptability to an area 

 of enormously wide geographical range, extending 

 from China to Britain. Nor is it a back -going 

 species, for though nowhere outrageously numerous, 

 it has extended its range in quite recent times to 

 such outlying parts as the Faroe Islands. But 

 the important thing about it is that its success 

 is securely based on nature, and if all the 

 artificial conditions created on the earth's surface 

 by civilized man were to disappear, the tree- 

 sparrow would not be seriously incommoded by 

 their disappearance. Human cultivation is not 



