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Show 36 UNCONSCIOUS SELECTION. CnAr. I. d t mblers with these breeds as now existing in B an •t . u I di·a and Persia we can, I think, clearly trace ri am, n , ' . · d the stages through which they have Insensi?ly passe , and come to differ so greatly from the rock-pigeon. Youatt gives an excellent illustration of. the effects of a course of selection, which may be considered as unconsciously followed, in so far that t~e breeders could never have expected or even have wished to have p:oduced the result which ensued-namely, the productiOn of two distinct strains. The two flocks of Leicester sheep kept by Mr. Buckley and Mr. Burgess, as Mr. Youatt remarks "have been purely bred from the original stock of ' . Mr. Bakewell for upwards of fifty years. There IS not a suspicion existing in 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 gentlemen is so great that they have the appearance of being quite different varieties." If there exist savages so barbarous as never to think of the inherited character of the offspring of their domestic animals, yet any one animal particularly useful to them, for any special purpose, would be carefully preserved during famines and other accidents, to which savages are so liable, and such choice animals would thus generally leave more offspring than the inferior ones ; so that in this case there would be a kind of unconscious selection going on. We see the value set on animals even by the barbarians of Tierra del Fuego, by their killing and devouring their old women, in times of dearth, as of less value than their dogs. In plants the same gradual process of improvement, through the occasional preservation of the best individuals, whether or not sufficiently distinct to be ranked CHAP. I. UNCONSCIOUS SELECTION. 37 at their first appearance as distinct varieties, and wheth r or not two or more species or races have b om blended together by crossing, may plainly be recognis d in the increased size and beauty which we now e in the varieties of the heartsease, rose, pelargonium, dahlia, and other plants, when compared with the older varietie or with their parent-stocks. No one would ever expect to get a first-rate heartsease or dahlia from the seed of a wild plant. No one would expect to raise a fir t-rate melti~g pear from the seed of the wild pear, though he might succeed from a poor seedling growing wild if i~ had c?me fro~ a ~arden-stock. The pear, though cul~Iv~ted In classwal times, 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 wond.erful skill of gardeners, in having produced sur.h splendid results from such poor materials ; but the art, I canno~ doubt, has been simple, and, as far as the final ~esult Is concerned, has been followed almo t unconsciOusly. I~ has consisted in always cultivating the best kno~ vanety, sowing its seeds, and, when a lightly better variety has chanced to appear, selecting it, and so onwards. But the gardeners of the cla ical p . d wh o cu lt.iv ate d the best pear they could procur n no ' thought what splendi~ f~uit we should eat ; tho~gh ::~ how e · our excellent fruit, m some small del'oY...r , t o tl1 e.r r aving naturally chosen and preserved the best vari tie they could anywhere find. A large amount of change in our cultivat d Jlant ~h~s ?lowly and unconsciously accumulated, explains a~ eheve, the well-known fact, that in a vast numbe; of ~~ses ~~ cannot recognise, and therefore do not know 1 e WI parent-stocks of the plants which have b ' o~gest cultivated in our flower and kitchen ard:: If It has taken centuries or thousands of years to If?m prove• |