By applying the theory of mutation and the techniques of breeding, new 

 "artificial" species of plants and animals have been established experimentally. 



On the basis of structure and form, on the basis of chemical and functional 

 characteristics, and on the basis of stages in development, human beings are 

 most like monkeys and apes. 



The blood of man is more Hke that of an ape than it is like that of a monkey, 

 and it resembles that of a monkey more than that of a lemur. 



From a biological point of \'ie\v, all human beings are of the same species, 

 notwithstanding the great variations among distinct "races". 



As with other species, inbreeding of human beings for many generations 

 appears to establish a fairly uniform type in a given localit)'. 



As in other species, hybridizing among human strains shows no effects that 

 are consistently advantageous or disadvantageous. 



EXPLORATIONS AND PROJECTS 



To find out about the origin and development of new varieties of vegetable, fruit 

 and crop plants or the recent developments in livestock, investigate among seeds- 

 men, horticulturists, poultrymen, dairymen, breeders of livestock, fanciers, or others 

 who have direct contact with the practical work of improving or multiplying live 

 plants or animals. Report on origins of new types that breed true — whether chance 

 discovery or deliberate creation; methods used, special value or interest, and so on. 



If direct information is not accessible, use catalogues, reports of associations, the 

 1936 and 1937 yearbooks of the United States Department of Agriculture, or other 

 sources. Summarize material to show how principles of heredity have been applied 

 in the development of new species. 



QUESTIONS 



1 What is the relation of an organism to the germ cells It bears? 



2 How did de Vries explain the origin of new species.? Upon what facts did he 

 base his explanation? What is there to support his explanation? What are its 

 limitations? 



3 What does an individual get from its environment.? from its ancestry by in- 

 heritance? 



4 How do you account for the origin of new species? 



5 What evidence Is there of man's relatedness to other organisms? To which 

 other groups is man most closely related? 



6 In what respects do we consider the origin of the human race like that of 

 other species? 



7 What evidence Is there that certain races are superior to other races? Why is 

 the evidence Inconclusive? What are the social and political Implications of the Issue? 



8 How might the universal use of airplanes and modern science Influence our 

 ideas of race superiority? 



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