152 ELEMENTARY ZOOLOGY. 



you have observed among animals of the same species. 

 What seems to be gained by the association? 



9. What is meant by degeneration among animals? 

 Under what circumstances do they degenerate. Cite 

 instances from your reading. 



10. In what respect are the higher animals better 

 adapted to the environment than the lower ones? 



1 1 . Why is the leap or spring a good adaptation for 

 capturing prey or escaping from enemies? Cite all the 

 instances which you know from your own observation. 



12. Discuss the value of the food-storing instinct. 

 To what is it an adaptation? Cite instances, together 

 with all the details you have observed. 



13. Is there any definite relation between the instinct 

 of home building and the degree of parental care? Use 

 both observation and reading. 



14. Study sleep among animals. What is its relation 

 to rest? To what is sleep an adaptation? When does 

 it commonly occur among animals? Why? Do plants 

 show any sleeping qualities? What is the condition of 

 the bodily activities during sleep? 



15. Give instances of animals being brought gradually 

 to endure conditions which would have killed them if 

 employed suddenly. What explanation can be offered 

 for this? 



1 6. Define habit. Why does the repeating of actions 

 tend to form habits? What is the value of this fact to 

 man and other animals? 



17. What do you understand by instinct? Look up 

 at least three authors on the subject. 



18. What gain is there to the child, in the human 

 species, because of the long period of dependence on the 



