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is betraying the bias bred by devotion to a favourite hypothesis. But it is needless to debate these figures. A myriad years or a million are much the same in an argument of this kind. The farther back, indeed, we carry the genesis of life, the more morally significant, by contrast, becomes the historic period, and the age of man. Even Mr. Darwin's enormous drafts will not break the bank of eternity.
14. Such the hypothesis. And doubtless Mr. Darwin has the signal merit of portraying, with a freshness and force altogether his own, what no preceding naturalist had seized with a like grasp—the important part played in the animal world by the constant competition for subsistence. Our author is the Malthus of Natural History. But it is one thing to discern the influential character of the struggle, and another to interpret its office or to decipher its results. Mr. Darwin insists that the struggle tends to change of the type, indefinite alteration of it for the better. Yet another reading, and an older, of the war of nature, is quite as likely to be true. What if animals were made from the first as “good” as they were ever meant to be; under no necessity of becoming better, though sometimes in danger of becoming worse? In that case the use of the struggle would
be preventive rather than promotive. Its function would be to conserve the type ; to recruit and re-invigorate the primordial form; and to maintain unimpaired the relative perfection with which that form was gifted by the moulding hand of the Creator. That this, and not its rival, is the true account of the matter, we may speedily be satisfied, if, suspending our guesses, we simply use our eyes. Struggle, everywhere in nature, means death to the sickly, the ricketty, and the feeble; and life to the healthy, the well-knit, and the strong. But precisely as these latter are preserved, a guarantee for purity of type is preserved along with them. The physical beauty and strength of certain South American and Polynesian tribes struck all our early voyagers : the reason was that none but the pick of their offspring survived the hardships of infancy. But these men were not progressing, in virtue of this ordeal, towards a superhuman estate : their perfectness consisted in conformity to the type, and not in transcending it. The struggle exists as guardian of the standard, and the severer the struggle the more typical the type. Through all her domains, Nature weeds out the weak. Be it so. A strong buffalo, on that very account, will have worthy heirs to his strength, and a fierze feline carnivore to its daring and ferocity. “Natural
selection” fulfils and exhausts its office, not by fostering but by checking deflexion in structure. Those savage
. Red Indians who are said to have cast their young boys into a river, leaving those to perish who could not save themselves by swimming, would doubtless rear thoroughbred Red Indians : no more : not a race with a promise of fins. Just so the tested buffalo will grow up rigidly herbivorous ; nor will the lion be set a-learning to eat straw like the ox.
15. Varieties will, indeed, arise which will be transient or permanent, according to definite and intelligible conditions. Permanent varieties spring from permanent
. causes-change of climate, supply of food, or the interference of man. Each of these, or any two, or all three of them combined, will produce, and that within a very limited space of time, extreme, though still superficial, diversities in size, colour, strength, and direction of natural instincts. 15 But none of these causes singly, nor all of them together, will work change in the dental formula, or the dorsal vertebræ, or the digestive and generative apparatus, or any other of those essential characters on which the comparative anatomist and physiologist rely. They will not disable the toxicologist from discriminating the blood-corpuscles of man from
those of a deer;16 they will not endow a dog with the retractile claw of the cat; nor a horse with canine teeth. Yet these are the only class of alterative agencies known to experience and observation. Competition, under whatever name disguised— Natural Selection, or Struggle for Life is not one of them. Certain changes
— in the superficial structure and habits of animals result from, and are perpetuated by, temperature, food, or artificial interference; but never, so far as we know, from free comity and intercourse, under like conditions, in a
state of nature.
16. Transient peculiarities, it is true, will occur in individual animals—such as the short legs in Seth Wright's ram, born 1791, and selected, as disabled from overleaping fences, as progenitor of the otter-breed. In the same way, men and women have been born with six fingers. But, along with this licence of rare and casual divergence, there is a law of constant revergence by which it is effectually controlled. Save by artificial fostering, such peculiarities cannot hold their ground. Every other member of the species in which they appear is arrayed against them, and in league to obliterate them. There is no variety of six-fingered men ; the sixth finger, or rather bud, for it is not a true digit
having no metacarpal socket, like the phalanges proper --lingers on against hopeless odds through a few generations; at last it is absorbed and conquered. 17 Nature, so to say, sets her face against it; and puts it under ban as a fugitive monstrosity. The ancon breed of sheep, when it ceased to be profitable, and so lost its artificial guardianship, rapidly merged in the general
Under the same law of revergence, dogs, on lapsing into the wild state, lose the habit of barking and only howl.18 So the wild boar of South America, after many centuries of intermediate domestication, has dropped the mask it was made to wear, and reappeared in the likeness of its prototype in the forest of Ardennes.19 Through constant milking, the ordinary domestic cow has come to have teats larger than in proportion, and the secretion of milk is perpetual. In Columbia, from the size of the farms, the practice of milking was laid aside. With what result ? “ In a few generations, the natural structure of parts and state of the function was restored. If the calf dies, the milk ceases to flow; and it is only by keeping him with his dam by day that an opportunity of obtaining milk from cows by night can be found.” 20 In such ways, nature shows her fundamental conservatism, and fidelity to