THE APPLICATION TO MAN 297 



rust, strong supporting straw, and a large yield per 

 acre. In the short time that has elapsed, Professor 

 Biffen has succeeded in producing strains of wheat that 

 combine all these desirable characters to a remarkable 

 degree. Such an immediate result would not have been 

 possible before 1900, when the rediscovery of Mendel's 

 law revolutionized man's knowledge of the action of 

 heredity in nature. 



This same knowledge which has made possible the 

 improvement of wheat may be applied with certain 

 reservations to the breeding of man, for there is no 

 reasonable doubt that man belongs in the same evolu- 

 tionary series with all other animals, as Darwin showed, 

 and is consequently subject to the same natural laws 

 to a considerable degree. 



It must be admitted that thus far in the progress of 

 civilization more attention has been directed to the 

 scientific breeding of animals and plants, little as that 

 has been, than to the scientific breeding of man. Let 

 us hope that the future will have a different story to 

 tell! 



2. MODIFYING FACTORS IN THE CASE OF MAN 



There are certain qualifying factors that make the 

 problems of genetics somewhat different in the case of 

 man than in other organisms. 



For example, mankind has come to be partially ex- 

 empt from some of the natural laws which affect other 

 organisms. Thus with respect to the workings of 

 natural selection man is partially under "grace" rather 

 than "law." Nature no longer "selects" good eyes in 



