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Show 40 UNCONSCIOUS SELECTION. [CU.AP, I. gardeners, in having produced such splendid results from such poor materials; but the art, I cano~ doubt, has been shnple, and, as far as the final result IS concerr;ed, h~s been followed aln1ost unconsciously. It ~as consi~ted .In always cultivating the best known .vanety, sowing Its seeds, and, whe:q. a slightly better variety has chanced to appear, selecting it, and so onw~rds. But the gardeners of the classical period, who cultivated the be.st pea~ they could procure, never thought what splendi~ f~uit we should eat · thouO'h we owe our excellent fruit, In soine small deO'r~e, to their having naturally chosen and preserved th~ best varieties they could anywhere find. A large amount of change in our cultivated. plants, thus slow{y and unconsciously accuT?-ulated, explains, as I believe the well-known fact, that In a vast number of cases V:e cannot recognise, and thererore do not know, the wild parent-stocks of the plant.s which have been l~ngest cultivated in our flower and kitchen gardens. If It bas taken centuries or thousands of years to improve or modify most of our plants up to their present standard of usefulness to man, we can understand how it is that neither Australia, the Cape of Good Hope, nor any other region inhabited by quite uncivi~ised man, has afforde~. us a single plant worth culture. It IS not that these countnes, so rich in species, do not by a strange chance possess ~he aboriginal stocks of any useful plants, ~ut that the ;nat1 ve plants have not been improved by contin?-ed selec~Ion up to a standard of perfection comparable With that given to the plants in countries anciently. civilised. . .. In regard to the domestic annuals kept by unCivihsed man it should not be overlooked that they almost always hav~ to struggle for their own food, at le~st during ~ertain seasons. And in two countries very differently Circumstanced, individuals of the same species, having slightly different constitutions or structure, would often succeed better in the one country than in the other, and thus by a process of "natural selection," as :vill hereafter be mo;e fully explained," two sub-breeds might be formed. Th1s, perhaps partly explains what has been remarked by some authors,' namely, that tho varieties kept by savages have CHAP I.) SELECTION BY MAN. 41 more of the character of species than the varieties kept in civilised countries. On the view here given of the all-important part which selection by 1nan 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 a 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 descendantq.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 inflate its crop much more than the turbit now does the upper part of its resophagus,-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 extremely 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 |