REFLEXES, INSTINCT, AND REASON 



431 



actions repeated till they become a " second nature " ever leave 

 a trace upon heredity. Such investigators regard instinct as 

 the natural survival of those methods of automatic response 

 which were most useful to the life of the animal, the individuals 

 having less effective methods of reflex action having perished, 

 leaving no posterity. 



An example in point would be the homing instinct of the 

 fur seal. When the arctic winter descends on its home in the 

 Pribilof Islands in Ber- 

 ing Sea, these animals 

 take to the open ocean, 

 many of them swim- 

 ming southward as far 

 as the Santa Barbara 

 Islands in California, 

 more than three thou- 

 sand miles from home. 

 While on the long 

 swim they never go 

 on shore; but in the 

 spring they return to 

 the northward, find- 

 ing the little islands 

 hidden in the arctic 

 fogs, often landing on 

 the very spot from 



which they were driven by the ice six months before, and 

 their arrival timed from year to year almost to the same 

 day. The perfection of this homing instinct is vital to their 

 life. If defective in any individual, he would be lost to the 

 herd and would leave no descendants. Those who return be- 

 come parents of the herd. As to the others the rough sea 

 tells no tales. We know that of those that set forth a large 

 percentage never come back. To those that return the homing 

 instinct has proved adequate. This must be so long as the race 

 exists. The failure of instinct would mean the extinction of 

 the species. 



The instincts of animals may be roughly classified as to their 

 relation to the individual into egoistic and altruistic instincts. 



Egoistic instincts are those which concern chiefly the in- 

 dividual animal itself. To this class belong the instincts of 



FIG. 266. A "pointer" dog in the act of "point- 

 ing," a specialized instinct. (Permission of G. O. 

 Shields, publisher of "Recreation.'') 



