FARM ANIMALS. 399 



preservation, the ability to gather food and to 

 protect themselves against other animals and 

 the climate, is necessary. The second function 

 of animal life is that of reproduction, which is 

 dependent upon general strength and vigor. 

 Animals in their natural state have developed 

 temperament, conformation and qualities that 

 best fit them for the performance of these life 

 functions. 



But under domestication great changes have 

 been wrought. Here to only a limited extent 

 may we say that animals exert themselves for 

 self-preservation. Their food, shelter and pro- 

 tection from other animals is supplied by man. 

 In domestic animals the process of reproduction 

 is largely directed by man, consequently they 

 have been relieved to some extent of the 

 primary functions of their existence. 



VII. Changes Wrought by Man. 



Man, however, expects remuneration for his 

 labor and his pains and seeks to obtain it in one 

 form or another. He not only lessens the 

 responsibility of domestic animals of their own 

 preservation and reproduction, but seeks by 

 proper nutrition, care and selection to develop 

 them to a high efficiency along a given line. 



As an example of this development, one may 

 note the dairy-cow. Observation taught that 

 some animals produced more milk than others. 

 Basing the procedure upon the law of heredity, 



