146 PO UL TR T- CRAFT. 



demonstration of one law of inheritance to account for all the phenomena of 

 likeness and unlikeness in fowls of the same blood and breeding should show 

 him that he can have virtually complete control of his stock, if only he will 

 breed in conformity to principles proved by the law of inheritance, rejecting 

 such so-called principles as will not stand the test. The right interpretation 

 of the facts of inheritance should show him that the uncertainty of results in 

 breeding, which he so often deplores, is not due to a conflict of mysterious 

 forces, but to his own avoidable mistakes. The law of inheritance shows that 

 by continued selection of the specimens most alike, the number and extent of 

 possible differences in the offspring are constantly reduced. There is nothing 

 new in this teaching. Successful breeders have followed it for years. But 

 that there is one law, and only one, which applies to all the phenomena of 

 reproduction, is the thing which, more than all others, the great mass of those 

 who are trying to breed poultry need to know. When once they get firm hold 

 of that fact, and form the habit of testing their methods by it, they will discard 

 some fallacies that now stand in the way of better general progress in the 

 improvement of domestic poultry. 



196. Selection. Inheritance perpetuates undesirable, as well as desir- 

 able, qualities. Its variations are as apt to be toward deterioration as toward 

 improvement. Among animals in a state of nature, natural selection, the 

 " survival of the fittest," constantly operates to maintain the old features, and 

 preserve and establish the new ones most beneficial to the race. In the 

 breeding of domestic animals natural selection necessarily plays a part, but 

 the chief factor is artificial selection, the " separation of the choicest," in 

 accordance with the interests or whims of the breeder. As an artificial 

 standard seeks to secure exact similarity in many details, or, very superior 

 excellence in one or more qualities, it is only by the most rigid selection of 

 the individuals allowed to propagate their kind that a high stage of improve- 

 ment can be reached and maintained. Rigid, severe selection is the key to 

 success in poultry breeding. If a breeder desires uniformity in his stock, the 

 breeding birds must be as nearly alike as can be had, and bred from like birds 

 for many generations. If he wishes to secure high excellence in a particular 

 quality, he must breed consecutively from the individuals in which that quality 

 is best developed without detriment to other qualities.* 



* NOTE. While a breeder should always select the best, he must expect that if a best 

 bird is so much better than the type in any particular that it is markedly unlike the type, 

 its progeny will not (unless it happens to be strongly prepotent with regard to the feature 

 which constitutes its excellence) show an equal excellence. On the contrary, it is in 

 accordance with the law that only a small proportion should do so, and that an equal 

 number should be as much worse than the poorest progeny of the mediocre stock as the 

 best are better than their best. So that, on the whole, the immediate progeny of 

 phenomenally good birds may be disappointing. But by breeding from the best again 

 and again, the marked advance made in any feature by an individual can be established 

 as a race feature, provided always that it can exist without detriment to other qualities. 



