PHASES OF ANIIVIAL LIFE 



birds, and in the colder seasons he raids the gran- 

 aries of the wild mice and the dens of the chip- 

 munks. He is a hustler and a freebooter at all times. 

 His natural enemies are black snakes, weasels, 

 hawks, owls, and cats, yet his tribe seems to be 

 increasing. 



Man, of course, disturbs the balance of Nature 

 wherever he goes. Some forms of life disappear 

 before him, while others thrive and increase in his 

 footsteps. He adds greatly to the food-supply of 

 some species, while he cuts off that of others. Most 

 of the field animals partake of his bounty, but the 

 forest animals vanish before him. That any species 

 has actually become extinct through his instru- 

 mentality, unless it be that of the passenger pigeon, 

 may well be doubted, though he hastened the extinc- 

 tion of the great auk, and, maybe, the Labrador 

 duck. The buffalo would have become extinct under 

 his ruthless slaughter, had he not stayed his hand 

 in time. Whole tribes and races of animals, some of 

 them fearfully and wonderfully made, became ex- 

 tinct in geologic time, long before man could have 

 played any part in hastening their doom. A change 

 in their environment, through slow crustal move- 

 ments of the earth, or through change of climate 

 that affected their food-supply, probably rendered 

 them unfit to survive. 



