18 LL55ON5 IN POULTRY KEEPING 5LCOND 5LRIL5. 



Students of the features of heredity recognize several very ^common phenomena: 

 The male offspring resemble their site, and the female offspring their dam. 

 The male offspring resemble their dam, and the female offspring their sire. 

 The offspring, both male and female, or either, resemble a grandparent more than 



either parent. 



The offspring may, fu any point considered, inherit from both sire and dam, their 

 quality being, in some degree, intermediate between the parents, or, in case of a 

 quality in which the parents are alike, being in excess of either. 



These are the most common and conspicuous features of heredity. In the breeding of pure 

 bred fowls, so like in many respects, it would be difficult to trace the influences of individual 

 parents and grandparents clearly enough to distinguish such phenomena in ordinary cases, but 

 they may be seen occasionally when birds of marked .prepotency are used for breeding, and 

 they are traced with ea*e in many mating* of cros>bred fowls, especially in points of strong 

 resemblance or great difference. 



J* 



I think the reader is now ready to believe that the phenomena of heredity are very complex. 

 Tne different features of heredity ju>t mentioned do not occur independently and separately. 

 All of them are sometimes observed, and in many degrees, in the progeny of a single mating, 

 and all may be accounted for by the general law of heredity given in the preceding lesson, 

 when considered in connection with a few other breeding principles*, such as prepotency, which 

 we have just discussed, and rever>ion or atavism, which will be discussed a little further on. 



The poi:t I wish to introduce here is that the law of heredity or inheritance is responsible 

 for variations from established or favorite types as well as for the perpetuation of those types. 

 It is often assumed that in the production of stock there are two warring tendencies the 

 tendency for like to beget like, and a tendency to variation, that is, to the production of features 

 differing from those found in the parents. These, supposedly different and antagonistic 

 tendencies are for the most part simply different manifestations of the same general law of 

 heredity, though there is no doubt that many variations in the way of special development due 

 to especially favorable conditions are at least in part transmitted to offspring. 



c* 



Let us see how variations, not due to external conditions, arise : 



All that the fowl is as it begins life as a chick it is by inheritance. In every part, feature, 

 characteristic, quality, and possibility it is like some ancestor. We found in studying the ques- 

 tion of inbreeding that the fowl inherited an appreciable part of its qualities from some thirty 

 nearest ancestors, and that the chances of a characteristic not found in any of these being pro- 

 duced were very remote. Still there is a chance that a feature long absent in a stock, though 

 common in its remoter ancestors, may reappear in some of them at any time; and I have heard 

 of a few instances in which it appeared that a characteristic of some very remote ancestor had 

 reappeared in a very large proportion of the stock produced in a season. This reappearance of 

 features supposed tafrave been completely eliminated is what is called reversion. It is rare in 

 stock that is carefully bred and new blood introduced with caution, but is quite common 

 when birds of similar type but very different breeding are mated, or when radically different 

 types of fowls are crossed. The beginner who in his eagerness to avoid inbreeding buys males 

 and females from different breeders and puts them together without knowing anything of the 

 breeding tendencies of either line of stock, is very apt to get some chicks that "take back" to 

 distant ancestors in which qualities not now wanted were conspicuous; and he generally con- 

 cludes that some of the stock he got was not "pure." While it is most common to have but a 

 siiii-'le feature reappear, once in a while one bird or a few birds are produced like a remote 

 ancestor in many points. 



Now suppose tb*t in place of simple reversion to a single ancestral characteristic which one 

 familiar with the stock or with the history of the production of a variety or breed will easily 

 recognize as such, a combination of features of two different ancestors takes place, or a min- 

 gling of an old with a modern feature. In such a case it may be possible to analyze the new- 

 character or type, but it may be impossible to do so, and in that case we have a variation which 



