DIFFERENTIATION OF INDIVIDTJALS AND ADAPTATION 1 43 



11. From reading and observation would you say that there is any definite 

 relation between the instinct for home-building and parental care? 



12. Study sleep among animals. What is its relation to rest? Is it found in 

 the lower animals? To what is sleep an adaptation? When does sleep commonly 

 occur among animals? Why? Do plants show any sleeping qualities? 



13. What are the principal geographical faunas recognized by zoologists. 

 Enumerate the more important means by which dispersal of animals from one 

 region to another occurs. What are the chief barriers to the dispersal of land 

 animals? of aquatic animals? 



14. Study the different authors to which you have access, as to the significance 

 of the terms species and variety (or subspecies). 



15. What were the older views concerning the "fixity" or invariability of 

 species? 



16. What are the different views of the "Origin of Species,'' as based on the 

 views of the meaning of species? 



17. What is the essential difference between the theories of "natural selection" 

 as stated by Darwin, and "definite variation," as explaining adaptation of organ- 

 isms to their environment. 



18.. What additional ideas are introduced by the "mutation" theory of De 

 Vries? What reasons does he give for thinking that natural selection is not a very 

 important factor in adaptation? Bearing of Johanssen's discoveries upon the 

 Darwinian theory? 



19. The bearing of Mendel's discoveries and the recent additions to these upon 

 such problems as variations; species; mutations; natural selection; adaptation. 



