« ПредыдущаяПродолжить »
fainily of languages be likened to the highest division in the animal kingdom, and the Chinese and other groups be paired off with the lower, then, on this writer's own showing, the main divisions at least must have a distinct original. But it is more important to note, that, whereas. languages are mere collections of words, animals are organized beings. The former are flexible in virtue of the boundless plasticity of the mental processes they portray. The latter are framed on anatomical principles, and endowed with physiological functions, which rise as invincible Barriers, at a certain limit of permitted divergence, and say, if universal experience is to be trusted,- -Hitherto, but no farther.
7. This, at least, is what our first authorities in Comparative Anatomy, such as Cuvier in the last generation, and Owen in this, have held, and do firmly hold and teach. And this is what Mr. Darwin, with great literary skill, and wide range of research and acquirement, is labouring with all his might to disprove and overturn. As others, indeed, have done before him ; notably Lamarck, and the author of the “Vestiges.” But what is peculiar to Mr. Darwin is the attempt to substitute a scientific and intelligible principle of animal progression for what, in these writers, as is now allowed on all
hands, is a mere fabric of visionary conjecture. He tries to slip a foundation under the Lamarckian scheme, and so to raise an unsubstantial hypothesis to the rank of a stable and fact-fortified theory. Species begets species, as individual begets individual ; and the lower species, step after step, have begotten the higher---this line of assertion is common to all these writers alike. But the third claims property in a new instrument of conviction, a new scientific method, alleged to be based on fresh observation of nature-of avail, its author thinks, to prove what his predecessors only dreamed. And this he calls the principle of “NATURAL SELECTION, or the preservation of favoured races in the struggle for life.”
8. Artificial Selection is as old as the patriarchs. Man has been, in rough fashion, a cattle-breeder from the days of Jacob, who produced varieties in Laban's flock, down to those of Seth Wright, of Massachussets, the rearer of the once celebrated otter-breed of sheep, and to those of the unsurpassed boviculturists of Aberdeenshire. To such perfection, moreover, has this art come within this century, that one authority, Lord Somerville, does not hesitate to say—“It would seem as if breeders had chalked out on a wall the most perfect form of a sheep, and then given it existence.” “Selection," Mr. Youatt tells us, with a like hyperbolical licence of expression " is the magician's wand, by which he may summon into life whatever form and mould he pleases.” “In Saxony," Mr. Darwin himself adds, “the importance of selection in regard to merino sheep is so fully recognized that men follow it as a trade; the sheep are placed on a table, and are studied like a picture by a connoisseur. This is done three times at intervals of mouths, and the sheep are each time marked and classed, so that the very best may ultimately be selected for breeding.” 9
9. What holds of the various tribes of cattle applies more or less to the other creatures that have come under the immediate influence and control of man. and sheep are modelled to suit the market, but a whim has given us our fancy-breeds of pigeons; and whim blends with an eye to fitness for work or consumption in the multifarious experiments on dogs, horses, and poultry.
10. Archimedes needs his fulcrum; and the pigeon, of all domesticated animals, is the selected fulcrum of Mr. Darwin. By the help of this feathered Proteus, his picked animal paradigma, he believes himself able to subdue to his hypothesis the whole feathered and featherless world of living creatures. On the one hand,
there is the original rock-pigeon, Columba livia, on the other, its curiously modified and metamorphosed progeny--the pompous fan-tail with its exuberant plumage, the pouter with its inflated crop, the tumbler with its curious somersaults in the air, the carrier, the trumpeter, and a host besides. These differences are esteemed by our author as exceedingly significant; such indeed as might surprise an ornithologist, were the birds found in the wild state, into a coinage not only of specific but of generic names.10 Yet all this divergence consists with a common stock; all this can be brought about, within the limits of a species, by the cultivation of peculiarities, century after century, on the part of man.
11. Such the powers of artificial or human selection --of man as the educator of brute nature. But is this the only sort of selection by which animals can be modified ? Mr. Darwin contends that it is not. Advantageous peculiarities, he holds, are incessantly fostered by a process quite apart from human interference. Which process is that of Natural Selection.
12. “ The Empire,” said the third Napoleon, "is peace.” Nature, says Mr. Darwin, with at least equal accuracy, is War. The whole world of living things is one scene of struggle, one vast arena of truceless con
flict, an unremitting competition for food and for exist
And the race is to the swift, and the battle to the strong. The table of nature is crowded with guests; the superfluous multitudes must be thrust out and trampled down. In this state of things, every peculiarity, however slight, which gives an animal an adrantage, however slight, over its rivals, will not only improve the fortunes of the individual, but probably travel down as an heirloom to its offspring. Let a peculiarity which chances also to be a prerogative emerge, and let members of the favoured race, at distant intervals but in definite directions, go on accumulating the like advantages; and we are assured that in such case, from mere “ varieties,” which our author contemplates as “incipient species,” there will issue fresh species, fully marked and developed, though not till after thousands or even myriads of generations. A peculiarity of this kind is deemed natural capital; and money makes money, it is thought, in the world of nature as in the world of man. There may and must be an infinity of failures, but there will be happy hits notwithstanding. In this fashion, according to Mr. Darwin, all the higher tribes have fought their way up through the incalculable periods of