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of sympathy can he influence or be influenced by his fellows within any social bounds. And thus it has been from the beginning, and must continue to be, so long as men are men, having the mental and moral traits by which we know them now as belonging to mankind.

Does any one suppose that the present high estate to which individual men and women, and some large aggregates of them, have risen in various portions of the earth was reached at a bound? Within historical times we know that it has not been so, and the evidence beyond them, exhumed from the earth, proves that it could never have been otherwise in prehistoric times, through all geological change, since man first became a denizen of this sphere. A savage he was, and a savage he remains, in many respects, yet; but an unmitigated savage he originally was, and universally was, and is not now. All that we see so admirable now in him is the result of an evolution, advancing, retarded, checked, progressing, passing through endless vicissitudes, until we find him now touching, in some races, upon the low intelligence and aspect of the brute, and elsewhere so glorious as to awaken the hope that his final earthly development may transcend our most fervent aspirations.

CHAPTER III.

NATURE'S EVIDENCE OF THE LAW OF LIFE AND GROWTH.

'HE preamble constituting the last chapter was necessary,

THE

lest the reader might not realize the intimate relation which the law of development bears to every passing incident of life. The evidence adduced by Darwin, Wallace, Spencer, and many others, in support of the alleged existence of the law, resolves itself in a general way into the categories of former geological change and the comparison of living with extinct forms of life, as known through living creatures and fossil remains. This chapter will be especially devoted to exhibiting some of the evidence upon which the existence of the alleged law rests, coupled with such manifestly implied considerations as to the importance of its recognition in the conduct of daily life as will obviate the necessity of their formal presentation.

All the varieties of what we call fancy-pigeons-carriers, tumblers, pouters, fan-tails, turbits, and others-are derived from the rock-pigeon, which is blue with black-barred wings. This has been proved by breeding those pigeons together in such a manner as to produce partial reversion to the assumed parent stock.

The results of the breeding of domesticated animals show that horses, cattle, sheep, and dogs can be so changed within their kind as to be hardly recognizable as derived from the animals which formed the point of departure. The same thing holds good of plants. The effect described is manifestly accomplished through artificial selection, as distinguished from natural selection, but this throws great light upon the question of natural selection. Artificial selection itself is naturally divided into two classes,-conscious and unconscious.

The selection is unconscious when, as often happens, a

person, not a breeder of animals or a cultivator of plants, effects a change by selection in either, without any remote ulterior object. Putting, for the sake of simplicity, plants out of consideration, and confining ourselves, as heretofore, to animals, the case referred to is illustrated by the occasional action of a person breeding, for the assumed improvement of certain qualities, from a pair of individuals which happen to please him by their traits. The selection, on the contrary, is conscious when, as with skilled breeders, generation after generation of animals is bred for the finest points of physical and mental traits, representing generally useful qualities. Speed is thus developed in horses, milk-giving or butter-making qualities in cows, hunting qualities in some dogs, size and ferocity in others, speed or household qualities in others; the qualities in some of these latter being not at all useful, but fanciful, as are the peculiarities of the French poodle, the King Charles spaniel, and the pug. But, whether the quality be useful or useless, it is proved that any amount of divergence is seemingly producible from the parent stock. This pursuit, even during an ordinary human life, suffices to produce wonderful changes in domestic animals. When breeders thus, through conscious selection, have pursued the same object,-that is, definite direction toward the object through several successive generations, the gradually-accumulated differences make at last in the animal under development a transfiguring result. Imagine what could be produced in the way of divergence of animal forms if men had the power and will, through continuous living, to carry on their conscious selection indefinitely. Imagine, then, the effect, if nature has been applying through thousands of years, millions, æons, a rigid selection, through a universal law of growth, life, and death, imposed by the Creator. We see it all around us, in our own persons, and in the whole outlying world. The present is the growth of the past, linked through endless series to the creation.

When a genus, the last bounds within which classification places species, consists of very many species and varieties, it is found that, throughout, the likeness between many forms is very close, and, moreover, that, grouped around special forms, are congeries or clusters of species and varieties, more closely similar to each other than are to each other the species generally of the inclusive genus. This is a very striking fact, awakening suspicion that such species, constituting the genus, have been molded through similarity and dissimilarity of conditions found in an extensive range, and, further, so as to form under continued individual similar and dissimilar conditions, continuously derived varieties, all of which may eventually become true species.

Species which are most abundant in individuals, and at the same time are most widely diffused in a single country, being there what may be properly termed the dominant species, exhibit the most numerous varieties. This phenomenon points in the same direction as that which has just been noticed, and, moreover, confirms its ultimate suggestion to the mind. That is to say, if variation is producible and produced from any cause whatever, we cannot say that the same cause is incapable of producing indefinite change; we cannot say that species may not be produced from varieties, and that the final product in the course of ages may not be quite dissimilar from the stock from which observation has been supposed to begin. Therefore, if natural selection as defined can produce change, it is impossible mentally to limit the amount of change.

There is a singular and surprising relation between the similarities and dissimilarities among animals found on continents and on the neighboring islands, and striking relations among animals inhabiting the islands themselves, pointing to primary differentiation as between the continental and insular forms and secondary differentiation as among the insular forms.

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