WHAT DO ANIMALS KNOW? 



we use the term ; the young ostrich does it as well as 

 the old. It is the inherited wisdom of the race, or 

 instinct. 



A sitting bird or fowl turns its eggs at regular 

 intervals, which has the effect of keeping the yolk 

 from sticking to the shell. Is this act the result of 

 knowledge or of experience ? It is again the result 

 of that untaught knowledge called instinct. Some 

 kinds of eggs hatch in two weeks, some in three, 

 others in four. The mother bird has no knowledge 

 of this period. It is not important that she should 

 have. * If the eggs are addled or sterile, she will often 

 continue to sit beyond the normal period. If the 

 continuance of the species depended upon her know- 

 ing the exact time required to hatch her eggs, as it 

 depends upon her having the incubating fever, of 

 course she would know exactly, and would never sit 

 beyond the required period. 



But what shall we say of Mrs. Annie Martin's 

 story, in her " Home Life on an Ostrich Farm," of 

 the white-necked African crow that, in order to feast 

 upon the eggs of the ostrich, carries a stone high 

 in the air above them and breaks them by letting it 

 fall ? This looks like reason, a knowledge of the rela- 

 tion of cause and effect. Mrs. Martin says the crows 

 break tortoise-shells in the same way, and have I not 

 heard of our own crows and gulls carrying clams 

 and crabs into the air and dropping them upon the 

 rocks ? 



135 



