Genetic Material 



Phenotypic variation among 

 associates in the Department 

 oj Zoology, Columbia Uni- 

 versity, 1954. Phenotypic 

 similarity is reflected in the 

 interest of numbered individ- 

 uals in genetical-cytological 

 matters. 



1. John A. Moore 



2. Arthur W. Pollister 



3. Howard Levene 



4. Francis J. Ryan 



5. Franz Schrader 



6. LesUe C. Dunn 



7. Theodosius Dobzhanksy 



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QUESTIONS FOR DISCUSSION 



1.1. Has the phenotype of one generation any effect upon the genotype of the next? Ex- 

 plain. 



1.2. What do you think of the thesis that the genotype is more important to organisms 

 than is the environment? 



1.3. Is the environment for two organisms ever identical? Explain. 



1.4. What is meant by an operational definition? 



1.5. Define the genetic factor. Have you given an operational or a nonoperational defi- 

 nition? Explain. 



1.6. When the same similarities or differences in phenotype can be produced by either the 

 environment or the genotype, can one ever be sure which is the determining factor? 

 Explain. 



1.7. What evidence can you give to support the view that the genetic material is transmitted 

 from parent to ofi'spring? Do you think this evidence constitutes conclusive proof of 

 transmission? Explain. 



1.8. What conclusions can you come to regarding the genetic factor in Himalayan rabbits 

 and in Siamese cats? 



1.9. Assume the genetic factor has a supernatural basis. Could we learn anything about 

 it from the use of the scientific method of investigation? Explain. 



1.10. Do you think human beings provide good material for the study of the genetic factor? 

 Explain. 



1.11. What size limitations can you give to the genetic material? 



1.12. Is the existence of genetic material presumed or proven? Explain. 



