SIZE MODIFIED BY CLIMATE 191 



It should be remembered, however, that inheritance 

 is always playing an important part, and that even 

 favorable climate and food combined cannot radically 

 change conformation and characteristics until long 

 periods of time have elapsed. 



Severe climatic conditions constantly tend to reduce 

 size. Such reduction ceases only when the body 

 structure has become adapted to all the forces acting 

 upon it, or, in other words, when an equilibrium has 

 been restored between energy produced and energy used. 

 Natural forces do not respect man's wishes ; they work 

 along the lines which accomplish their purposes in the 

 most economical way. Rigorous climatic conditions tend 

 not only to diminish size but to eliminate highly special- 

 ized qualities and to produce hardiness the prime 

 characteristics which must be perpetuated if existence is 

 maintained. 



In America, serious mistakes have been made by 

 placing some of the imported breeds under climatic con- 

 ditions so much more rigorous than those to which they 

 were accustomed as to preclude the possibility of 

 securing expected results. Since we have become more 

 humane in the winter-housing and treatment of animals, 

 the breeds brought from a warmer climate than that in 

 which they are placed in the States preserve their 

 specialized qualities intact under skilful management. 

 Still, there is always danger in moving animals from 

 one climate to another radically different, especially if it 

 be from a warmer to a colder one. 



