478 POULTRY CULTURE 



of type as compared with that of the male increases ; for while the 

 male may still influence a very much larger number of offspring, 

 the female may produce enough offspring in a season to enable a 

 breeder to produce in the next season hundreds or even thousands 

 of young from matings of her offspring. As between a male and 

 female of equal breeding value, polygamous mating constitutes a 

 handicap of one generation on the female. This, where a genera- 

 tion matures in less than a year, is a very slight difference. An 

 experienced and skillful poultry breeder places as high a value 

 on the female in his breeding operations as on the male, though 

 commercially the male is more valuable because a purchaser may 

 realize more quickly on his investment. 



Selection. In nature the established type of a species or a variety 

 is the type that is best adapted to its environment. Such types 

 develop as a result of natural selection, defined by Darwin as " the 

 survival of the fittest." In improved domestic races types are arbi- 

 trarily determined by man in accordance with his needs or his 

 tastes, and are secured and maintained by allowing only individuals 

 of the desired types to propagate their kind. Such types are called 

 artificial types (breeds) and the system of selection by which they 

 are made and preserved is called artificial selection. 



Superficially, artificial and natural selection often seem to pro- 

 ceed on radically different principles, and so are by many regarded 

 as essentially antagonistic. The impression is very general that 

 artificial selection is unnatural, at variance with nature. This is 

 true only when by artificial selection the development or suppres- 

 sion of a character is carried to the point where the result becomes 

 detrimental to the race. In domestication natural selection becomes 

 in a measure inoperative, and the natural type varies and multi- 

 plies indefinitely. Artificial, or intelligent, selection then becomes 

 necessary for the isolation and development of a limited number 

 of the types arising. In the wild state conditions make it impos- 

 sible for many special types of a species to develop in the same 

 territory. In domestication, man may develop, by the control and 

 separation of individuals, as many types as he wishes. As long as 

 selection does not unduly disturb the natural equilibrium of char- 

 acters, artificial selection is not unnatural ; and in so far as, with- 

 out injury to others, it develops special characters beyond what 



