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must therefore be very careful to remember that the tail of the horse, or the cow, or the giraffe, grew very slowly; and this of course means geological slowness. But a cow or horse with a tail only the hundred-thousandth part of its present length would not reap much benefit from the addition: it would only be appreciable by a powerful microscope, and would be of no advantage to its proprietor as far as we can see. Let us suppose that at the end of some thousand years a cow's tail had grown an inch long, it would certainly avail nothing for the flagellation of insects, nor can we see any reason why this slowly-improving cow or horse should by this slight variation' gain the victory in the competition for existence; nevertheless, cows' tails grew by Natural Selection, till at last they came to be those instruments which we now see them to be, mutatis mutandis. This sort of history is applicable to every animal-to the trunk of the elephant, the horns of the deer, the hoof of the horse, &c.

This, however, incidentally lets us into a secret, that in all these dreams of transformation a prospective advantage is always implied, as is obvious in this history of tails. No organ can be made suddenly, that is a fundamental rule in the theory; nevertheless, every remarkable organ has been slowly advancing in its formation, till it becomes the instrument requisite for some particular purpose, and then it advances no more. This implies, and means, that there is a design somewhere. Mr Darwin may shrink from this as he likes, but his slow growth of organs tending to an object, and that growth ceasing when the object is obtained, means only slow design. Mr Darwin may flatter himself that his millions of ages may conceal this, but it only makes apparent, that when any one tries to explain

CHAPTER V.

THE FUNCTIONS OF NATURAL SELECTION.

HAVING established the meaning of Natural Selection, we go on to consider the functions assigned to it in the theory.

'Natural Selection can only act through and for the good of each being;' and on this principle it chooses colours, makes leaf-eating insects green, and bark-feeders mottlegrey, the ptarmigan white in winter, the red grouse the colour of the heather, and the black grouse that of peaty earth. Grouse, if not destroyed at some period of their lives, would increase in countless numbers-hawks are guided by eyesight to their prey. Hence,' says the author, 'I can see no reason to doubt that Natural Selection might be most effective in giving the proper colour to each kind of grouse, and in keeping that colour, when once acquired, true and constant' (89).

Natural Selection, therefore, foresaw the proper colour for effecting concealment, gave the tint that would best answer the purpose, and has preserved it.

'We must believe,' says Mr Darwin, 'that these tints are of service to these birds and insects in preserving them from danger.' There is no difficulty in believing this, we always have believed it; but then the question arises, as these colours have been assigned to the animals to preserve

them from danger, whose was the provident intellect that devised and predetermined this mode of defence, and then produced the means to render it efficacious? We have no difficulty in answering the question, but in this theory no providential design, no supreme creative will, can be admitted; so that, if we ask again how these protecting tints were produced, we learn by referring to the definition, that it was by the aggregate action and product of the sequence of events as ascertained by us.' That is, we see things in a certain form, and that is the reason of their being so. Colours are produced to defend animals from danger, and answer the purpose well, but they were not designed or devised to produce this beneficial effect, but they have become what they are by a sequence of events; the effect is the cause of the effect; events produce themselves, and that is the cause of their being produced.

Now, as the author of this profound theory frequently reminds us of the vast superiority of the achievements of Natural Selection over anything that man can devise or accomplish, we are at liberty to apply this sort of reasoning with much greater force to the productions of human skill, as it must be so much easier to make machinery, such as is produced by the hands of man, than to imitate the smallest of the works of nature. When therefore we see a superior watch, or a highly improved steam-engine, and are asked who made them, we may confidently affirm that they were not designed or made by any one, but are the result of the aggregate action, and the product of the sequence of events. as ascertained by us.'

But to proceed with the functions of the great Improver. Natural Selection gave winged seeds to the dandelion. If it profit a plant to have its seeds more and more widely

disseminated by the wind, I see no greater difficulty in this being effected through Natural Selection than in the cotton-planter increasing and improving by selection the down in the pods of his cotton-trees' (91). Most people would say that it was not quite so easy to give wings to seeds as to improve cotton-plants by selecting the most downy pods. Mr Darwin seems to find no difficulty in it, but by what process he would enable a kidney-bean, a pea, or a mustard-seed to fly through the air he has not informed us. Wings however are a ready article in the theory, as we shall hereafter see.

In this particular case, it should be noted that the dandelion has not only improved itself, as every other being has in this theory, but it has had an eye to the benefit and settlement of its progeny. It has foreseen that it would 'profit' its family 'to be more and more widely disseminated,' and having therefore determined to make its descendants colonists, has invested its seeds with volant qualities, to find their fortunes, as aëronauts, far away from the parental station.

Manifold are the transformations which have been brought about in the process of time, for we may believe that the progenitor of the ostrich was the bustard, and that as Natural Selection increased, in successive generations, the size and weight of the body, its legs were used more and its wings less, till they became incapable of flight' (152). In this authentic history of the feathered race we have the counterpart to the acquisition of wings, for it seems that animals may not only acquire wings but also get rid of the faculty of flying, though in this particular instance it is difficult to ascertain what the bustard has gained by turning himself into an ostrich. Considering the calamities that this

change has brought on the ostrich, one of the most persecuted of animals, we suspect he would not be sorry to return to his bustard origin if only he knew how. Natural Selection always operates for the benefit of the changing animal, but whether when animals have got into a scrape by bettering themselves,' they can get out of it by retrogressive selection is perhaps a fact not yet determined.*

As however the breed of bustards still exists, it is clear that some only of that species were disposed to make the change the more sober ones were content with the actual state of things, and thought it better to let well alone.'

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As a general proposition we are to understand that wings may be acquired where they did not previously exist. 'It requires a long succession of ages to adapt an organism to some new and peculiar form of life, as for instance to fly through the air (328); and, indeed, it is essential to this theory that every existing bird should have acquired the faculty of flight, not by original constitution and appointment, but by gradual mutation, and accumulation of beneficial qualities, tending to the development of wings. Mr Darwin discusses this transformation with well-sustained gravity, and finishes with these words:

'We do not see the transitional grade through which the wings of birds have passed; but what special difficulty is there in believing that it might profit the modified descendants of the penguin, first to become enabled to flap along the surface of the sea, like the logger-headed duck, and ultimately to rise from its surface and glide through the air?' (329).

Such passages as these seem almost incredible in a

* Retrogressive Natural Selection seems to be admitted in the theory. On this subject more will be said hereafter.

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