

23 Unconscious Selection. Chap. \ 



ex 



explains why the varieties kept by savages, as has been remarked 

 by some authors, have more of the character of true species than the- 

 varieties kept in civilised countries. 



On the view here given of the important part which selection by 

 man has played, it becomes at once obvious, how it is that our 

 domestic races show adaptation in their structure or in their habits- 

 to man's wants or fancies. We can, I think, further understand the- 

 frequently abnormal character of our domestic races, and likewise 

 their differences being so great in external characters, and relatively 

 so slight in internal parts or organs. Man can hardly select, or 

 only with much difficulty, any deviation of structure excepting such 

 as is externally visible ; and indeed he rarely cares for what is- 

 internal. He can never act by selection, excepting on variations 

 which are first given to him in some slight degree by nature. No 

 man would ever try to make a fantail till he saw a pigeon with 

 a tail developed in some slight degree in an unusual manner, or & 

 pouter till he saw a pigeon with a crop of somewhat unusual size ; 

 and the more abnormal or unusual any character was when it first 

 appeared, the more likely it would be to catch his attention. But 

 to use such an expression as trying to make a fantail, is, I have no- 

 doubt, in most cases, utterly incorrect. The man who first selected 

 a pigeon with a slightly larger tail, never dreamed what the descend- 

 ants of that pigeon would become through long-continued, partly 

 unconscious and partly methodical, selection. Perhaps the parent- 

 bird of all fantails had only fourteen tail-feathers somewhat expanded,, 

 like the present Java fantail, or like individuals of other and distinct 

 breeds, in which as many as seventeen tail-feathers have been 

 counted. Perhaps the first pouter-pigeon did not innate its crop, 

 much more than the turbit now does the upper part of its oeso- 

 phagus,— a habit which is disregarded by all fanciers, as it is not 

 one of the points of the breed. 



Nor let it be thought that some great deviation of structure- 

 would be necessary to catch the fancier's eye : he perceives ex- 

 tremely small differences, and it is in human nature to value any 

 novelty however slight, in one's own possession. Nor must the 

 value which would formerly have been set on any slight differences 

 m the individuals of the same species, be judged of by the value- 

 which is now set on them, after several breeds have fairly been 

 established. It is known that with pigeons many slight variation* 

 now occasionally appear, but these are rejected as faults or devia- 

 tions from the standard of perfection in each breed. The common, 

 jfoose has not given rise to any marked varieties; hence the Tou- 

 louse and the common breed, which differ only in colour, that most 



