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Show 238 SELECTION, CuAr. xxr. The importance of selection is likewise shown by considering special characters. For instance, with most breeds of fowls the form of the comb and the colour of the plumage have been attended to, and are eminently characteristic of each race; but in Dorkings, fashion has never demanded uniformity of comb or colour; and the utmost diversity in these respects prevails. Rose-combs, double-combs, cup-combs, &c., and colours of all kinds, may be seen in purely-bred and closely related Dorking fowls, whilst other points, such as the general form of body, and the presence of an additional toe, have been attended to, and are invariably present. It has also been ascertained that colour can be fixed in this breed, as well as in any other.51 During the formation or improvement of a breed, its members will always be found to vary much in those characters to which especial at~ention is directed, and of which each slight improvement IS eagerly sought and selected. Thus with short-faced tumbler-pigeons, the shortness of the beak, shape of head and plumage,-with carriers, the length of the beak and wattle - with fantails, the tail and carriage,-with Spanish fowls, the wl:ite face and comb,-with long-eared rabbits, the lenoth of ear are all points. which ~re em~nently variable. So it i: in every 'case, and the larg~ pnce paid for first-rate animals proves the difficul~ y of ?reedmg them up to the highest standard of excellence. T~Is SU~Ject has b~en di~cussed by fanciers, 52 and the greater pnzes ?wen for highly Improved breeds, in comparison with ~hose given for old breeds which are not now undergoina rapid l:Up.rovement, has been fully justified. N athusius makes 53 a ~Imilar remark when discussing the less uniform character of Im~roved Shorthorn cattle and of the English horse, in compans? n, for example, with the unennobled cattle of Hungary, or w~th .the horses of the Asiatic steppes. This \.Yant of unifm: mity m the parts which at the time are undergoing selection, chie~y ~epe~ds on the strength of the principle of reversion : but It likewise depends to a certain extent on the continued • 51 Mr. Baily, in ' The Poultry Chrorucle,' vol. ii., 1854, p. 150. Also vol. i. P· ~42/ vol. iii. p. 245. " Cottage Gardener,, 1 855, De-ccmber, p. 171; 1856 January pp. 248, 323. ' ' 53 'Ueber Shorthorn Rindvieh,' 1857, s. 51. OtU.P. XXI. CARRIED TO AN EXTREME. 239 variability of the parts which have recently varied. That the same parts do continue varying in the same manner we must admit, for, if it were not so, there could be no improvement beyond an early standard of excellence, and we know that such improvement is not only possible, but is of general occurrence. As a consequence of continued variability, and more especially of reversion, all highly improved races, if neglected or not subjected to incessant selection, soon degenerate. Youatt gives a curious instance of this in some cattle formerly kept in Glamorganshire ; but in this case the cattle were not fed with sufficient care. 1\fr. Baker, in his memoir on the Horse, sums up: "It must have "been observed in the preceding pages that, whenever there bas "been neglect, the breed has proportionally deteriorated." 54 If a considerable number of improved cattle, sheep, or other animals of the same race, were allowed to breed freely together, with no selection, but with no change in their condition of life, there can be no doubt that after a score or hundred generations they would be very far from excellent of their kind; but, from what we see of the many common races of dogs, cattle, fowls, pigeons, &c., which without any particular care have long retained nearly the same character, we have no grounds for believing that they would altogether depart from their type. It is a general belief amongst breeders that characters of all kinds become fixed by long-continued inheritance. But I have attempted to show in the fourteenth chapter that this belief apparently resolves itself into the following proposition, namely, that all characters whatever, whether recently acquired or ancient, tend to be transmitted, but that those which have already long withstood all counteracting influences, will, as a general rule, continue to withstand them, and consequently be faithfully transmitted. Tendency in Man to carry the practice of Selection to an extreme point. It is an important principle that in the process of selection man almost invariably wishes to go to an extreme point. Thus, in useful qualities, there is no limit to his desire to breed certain 54 'The Veterinary,' vol. xiii. p. 720. For the Glamorganshire cattle, see Youatt on Cattle, p. 51. |