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Show 38 liNCONSCIOUS SELECTION. [CHAP. I. did greatly 1nodify, even during their own lifetimes, the forms and qualities of their cattle. Slow and insensible changes of this kind could never be recognised unless actual measurements or careful drawings of the breeds in question had been made long ago, which might serve for comparison. In some cases, however, unchanged or but little changed individuals of the same breed may be found in less civilized districts, where the breed has been less ilnproved. There is reason to believe that King Charles's spaniel has been unconsciously modified to a large extent since the ti~e of that monarch. Some highly competent authorities are convinced that the setter is directly derived from the spaniel, and has probably been slowly alteTed fr01n it. It is known that the English pointer has been greatly ~hanged \vithin the last century, and in this case the change has, it is believed, been chiefly effected by crosses with the fox-hound ; but what concerns us is, that the change has been effected unconsciously and gradually,. and yet so effectually, that, though the old Spanish pointer certainly came from Spain, Mr. BolTOW has not seen, as I am informed by hirn, any native dog in Spain like our pointer. By a similar process of selection, and by careful training, the whole body of English race-horses have come to surpass in fleetness and size the parent Arab stock, so that the latter, by the regulations for the .Goodwood Races, are favoured in the weights they carry. Lord Spencer and others have shown how the cattle of England have increased in weight and in early maturity, compared with the stock formerly kept in this country. By comparing the accounts .s-iven in old pigeon treatises of carriers and tumblers w1th these breeds as now existing in Britain, India, and Persia, we can, I think, clearly trace the stages through which they have insensibly passed, and come to differ so greatly from the rock-pig~on. Youatt gives an excellent illustration of the effects of a course of selection, which may be considered as unconsciously followed, in so far that the breeders could never have expected or even have wished to have produced the result which ensued-namely, the production of two dis- Cn.A.P. I.] UNCONSCIOUS SELECTION. 39 tinct strains. The two flocks of Leicester sheep kept by Mr. Buckley and Mr. Burgess, as Mr. Y ouatt remarks ''have been purely bred from the original stock of Mr: B.al~ewell .fo: up:vards of .fifty ~years. There is not a susPI. mon existing 1n the mind of any one at all acquainted With the subJect that the owner of either of them has deviated in any one instance from the pure blood of Mr. Bakewell's flock, and yet the difference between the sheep possessed by these two gentlen1en is so great that t~e:y have the appearance of being quite different val'letles." If there exist savages so barbarous as never to think of ~he inherited characte~ of the offspring of their domestic aninlals, yet any one an1mal particularly useful to them ~or any ~pecial purpose, would be carefully preserved dur~ 1~g famines and ot~er accidents, to which savages are so hable, and ~uch choice a~ima~s would thus generally leave n1ore offspnng than the Infenor ones · so that in this case there would be a kind of .unconscio~s selection going on. ~ e see the value set on animals even by the barbarians of Tien·a ~el J!uego, by their killing and devouring their old won1en In times of dearth, as of less value than their doD's. In plants the. same gradual process of improveme~t through the occasional preservation of the best individuals' whether or not sufficiently distinct to be ranked at their :first appearance as distinct varieties, and whether or not two o~ m?re species or. races have be?ome. blende.d together by crossing, may plainly be recognised 1n the Increased size and beauty which we now see in the varieties of the heartsease, rose, pe~argonium, dahlia? ~nd other plants, when compared With the older varieties or with their parent-stocks. No one would ever expect to get a firstrate heartsease or dahlia from the seed of a wild plant. No one would expect to raise a first-rate meltinO' pear frorn the seed of the wild pear, though he might s~cceed from a poor seedling growing wild, if it had come from a ~arden-stock. The pear, though cultivated in classical tur~es, appears, from Pliny's description, to have been a fruit of very inferior quality. I have seen great surprise expressed in horticultural works at the wonderful skill of |