68 THE MEANING OF EVOLUTION 



has been here a fit quality and has helped him in 

 the race. 



Man is only slowly coming to be a city-dwelling 

 animal. Although it is a voluntary process with him, 

 he still usually visits the country with much enjoy- 

 ment. He has not as yet learned to adapt himself 

 thoroughly to the city, for somehow city life kills 

 him. Families that move into the city gradually have 

 a smaller number of children in each generation until 

 shortly the family is wiped out. The population of 

 the city must constantly be replenished from the coun- 

 try. But the English sparrow is more adaptable than 

 are the people. He has made himself at home in the 

 heart of the biggest city. The Wall Street canyon is 

 not deep enough, nor contracted enough, nor free 

 enough of food to blot out the life of the English 

 sparrow. At the heart of the deepest gully among 

 the skyscrapers of our biggest cities we find this little 

 bird hopping between the horses' feet, darting out 

 from under the wheel of the push-cart, fluttering only 

 a few yards to a place of safety, to return at once to 

 his scanty meal upon the pavement as soon as oppor- 

 tunity offers. He is a typical city dweller and has 

 learned to thrive there. Again in this matter he has 

 distanced other birds to whom the city is more deadly 

 than it is to people. 



Another very important element in his fitness for 



