Page:The Times, Origin of Species.djvu/1

 DARWIN ON THE ORIGIN OF SPECIES There is a growing immensity in the speculations of science to which no human thing or thought at this day is comparable. Apart from the results which science brings us home and securely harvests, there is an  expansive force and latitude in its tentative efforts, which lifts us  out of ourselves and transfigures our mortality. We may have a preference for moral themes, like the Homeric sage, who had seen and  known much:— "Cities of men "And manners, climates, councils, governments;"  yet we must end by confession that "The windy ways of men Are but dust which rises up "And is lightly laid again," in comparison with the work of nature, to which science testifies, but which has no boundaries in time or space to which science can  approximate. There is something altogether out of the reach of science, and yet the compass of science is practically illimitable. Hence it is that from time to time we are startled and perplexed by theories which have no  parallel in the contracted moral world; for the generalizations of  science sweep on in ever-widening circles, and more aspiring flights,  through a limitless creation. While astronomy, with its telescope, ranges beyond the known stars, and physiology, with its microscope, is  subdividing infinite minutiae, we may expect that our historic  centuries may be treated as inadequate counters in the history of the  planet on which we are placed. We must expect new conceptions of the nature and relations of its denizens, as science acquires the materials  for fresh generalizations; nor have we occasion for alarms if a highly  advanced knowledge, like that of the eminent Naturalist before us,  confronts us with an hypothesis as vast as it is novel. This hypothesis may or may not be sustainable hereafter; it may give way to  something else, and higher science may reverse what science has here  built up with so much skill and patience, but its sufficiency must be  tried by the tests of science alone, if we are to maintain our position  as the heirs of Bacon and the acquitters of Galileo. We must weigh this hypothesis strictly in the controversy which is coming, by the only  tests which are appropriate, and by no others whatsoever. The hypothesis to which we point, and of which the present work of Mr. Darwin is but the preliminary outline, may be stated in his own language as follows:—"Species originated by means of natural  selection, or through the preservation of the favoured races in the  struggle for life." To render this thesis intelligible, it is necessary to interpret its terms. In the first place, what is a species? The question is a simple one, but the right answer to it is hard to find, even if we appeal to those who should know most about  it. It is all those animals or plants which have descended from a single pair of parents; it is the smallest distinctly definable group  of living organisms; it is an eternal and immutable entity; it is a mere  abstraction of the human intellect having no existence in nature. Such are a few of the significations attached to this simple word which may  be culled from authoritative sources; and if, leaving terms and  theoretical subtleties aside, we turn to facts and endeavour to gather a  meaning for ourselves, by studying the things to which, in practice,  the name of species is applied, it profits us little. For practice varies as much as theory. Let the botanist or the zoologist examine and describe the productions of a country, and one will pretty certainly  disagree with the other as to the number, limits, and definitions of  the species into which he groups the very same things. In these islands, we are in the habit of regarding mankind as of one species, but  a fortnight's steam will land us in a country where divines and  savants, for once in agreement, vie with one another in loudness of  assertion, if not in cogency of proof, that men are of different  species; and, more particularly, that the species negro is so distinct  from our own that the Ten Commandments have actually no reference to  him. Even in the calm region of entomology, where, if anywhere in this sinful world, passion and prejudice should fail to stir the mind, one  learned coleopterist will fill ten attractive volumes with descriptions  of species of beetles, nine-tenths of which are immediately declared by  his brother beetle-mongers to be no species at all. The truth is that the number of distinguishable living creatures almost surpasses imagination. At least a hundred thousand such kinds of insects alone have been described and may be identified in collections,  and the number of separable kinds of living things is underestimated  at half a million. Seeing that most of these obvious kinds have their accidental varieties, and that they often shade into others by  imperceptible degrees, it may well be imagined that the task of  distinguishing between what is permanent and what fleeting, what is a  species and what a mere variety, is sufficiently formidable. But is it not possible to apply a test whereby a true species may be known from a mere variety? Is there no criterion of species? Great authorities affirm that there is—that the unions of members of the  same species are always fertile, while those of distinct species are  either sterile, or their offspring, called hybrids, are so. It is affirmed not only that this is an experimental fact, but that it is a  provision for the preservation of the purity of species. Such a criterion as this would be invaluable; but, unfortunately, not only is  it not obvious how to apply it in the great majority of cases in which  its aid is needed, but its general validity is stoutly denied. The Hon. and Rev. Mr. Herbert, a most trustworthy authority, not only  asserts as the result of his own observations and experiments that many  hybrids are quite as fertile as the parent species, but he goes so far  as to assert that the particular plant Crinum capense is much more  fertile when crossed by a distinct species than when fertilised by its  proper pollen! On the other hand, the famous Gaertner, though he took the greatest pains to cross the primrose and the cowslip, succeeded  only once or twice in several years; and yet it is a well-established  fact that the primrose and the cowslip are only varieties of the same  kind of plant. Again, such cases as the following are well established. The female of species A, if crossed with the male of species B, is fertile; but, if the female of B is crossed with the male  of A, she remains barren. Facts of this kind destroy the value of the supposed criterion. If, weary of the endless difficulties involved in the determination of species, the investigator, contenting himself with the rough practical  distinction of separable kinds, endeavours to study them as they occur  in nature—to ascertain their relations to the conditions which  surround them, their mutual harmonies and discordances of structure,  the bond of union of their parts and their past history, he finds  himself, according to the received notions, in a mighty maze, and with,  at most, the dimmest adumbration of a plan. If he starts with any one clear conviction, it is that every part of a living creature is  cunningly adapted to some special use in its life. Has not his Paley told him that that seemingly useless organ, the spleen, is beautifully  adjusted as so much packing between the other organs? And yet, at the outset of his studies, he finds that no adaptive reason whatsoever can  be given for one-half of the peculiarities of vegetable structure; he  also discovers rudimentary teeth, which are never used, in the gums of  the young calf and in those of the foetal whale; insects which never  bite have rudimental jaws, and others which never fly have rudimental  wings; naturally blind creatures have rudimental eyes; and the halt  have rudimentary limbs. So, again, no animal or plant puts on its perfect form at once, but all have to start from the same point,  however various the course which each has to pursue. Not only men and horses, and cats and dogs, lobsters and beetles, periwinkles and  mussels, but even the very sponges and animalcules commence their  existence under forms which are essentially undistinguishable; and this  is true of all the infinite variety of plants. Nay, more, all living beings march side by side along the high road of development, and  separate the later the more like they are; like people leaving church,  who all go down the aisle, but having reached the door some turn into  the parsonage, others go down the village, and others part only in the  next parish. A man in his development runs for a little while parallel with, though never passing through, the form of the meanest worm, then  travels for a space beside the fish, then journeys along with the bird  and the reptile for his fellow travellers; and only at last, after a  brief companionship with the highest of the four-footed and four-handed  world, rises into the dignity of pure man