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THE GROWTH OF SENTIENCY.

MULTIPLICATION is the primal lesson of living beings. If all the plants upon the surface of the earth should be destroyed except one young palm, one young oak, and one young pine, and these should be allowed to bear their fruits, and every seed should grow and reproduce its kind in a succession of generations, the palm, the oak, and the pine might live to see their progeny covering the whole earth. And the younger palms, oaks, and pines would stand so dense under the shadow of the taller forests that the world would be a jungle impenetrable to the larger beasts. Such are the powers of reproduction with which palms, oaks, and pines are endowed; and yet they do not equal those of many lower orders. This marvelous fecundity, especially in the lower forms, has played an important part in the evolution of plants, the nature of which must be understood. Few plant germs reach adult life. Every successful passage through the term of existence is offset by a multitude of failures. The life of the very few is secured by the martyrdom of the very many.

If many are called and few are chosen, how are the favored few selected? The answer is the modern doctrine of evolution; it is the principle of "the survival of the fittest in the struggle for existence"; it is the philosophy that Darwin embodies in the phrase "natural selection." Nature gives more lives than she can support. There is not enough food for the individuals requiring it, and only those live that obtain sufficient nutriment. There is not enough room for the growth of all the germs produced, and only those live that find a habitat. Of the multitude, some perish on the rocks, some languish in the darkness, some are drowned in the waters, and some are devoured by animals. The few live because they do not fall on the rocks, but are implanted in the soil; because they are not buried in the darkness, but are bathed in the sunlight; because they are not

overwhelmed by deep waters, but are nourished by gentle rains; because they are not devoured by the hungry, but dwell among the living. The few live, in other words, because they are the favorites of surrounding circumstances. In the more stately phrase of the philosophy of evolution, they are "adapted to the environment." But this general statement must be followed a little further, that its deeper significance may be grasped.

The earth, as the home of living beings, presents an almost infinite variety of conditions, and beings not adapted to one set of these may be adapted to another; so that a great variety of living forms are produced, suited to a great variety of circumstances. Plants are developed to live in air, on the land, and in the sea; in polar zones, in temperate lands, and in torrid regions; on mountains, on plains, and in valleys; in arid lands and in humid lands. The life which teems upon the earth is thus crowded into every available spot, and yet the fountains of life never fail. Every spring sends its stream into the flooded world. There is life for all the earth, and more life, and still more life; forever and forever it comes. Under such conditions of abundance, of wanton superfluity, the new-born plants are ushered into the world to compete with one another for continued existence. Thus the whole world of vegetable life is in a struggle; all plants are engaged in warfare one with another.

Let us look at some of the ways in which this competition is carried on. The plant must have air and water, for its food is the body of the wind and its drink the body of the storm; but food and drink are only the vehicles of life, not life itself. Plant life is sunlight, transformed and organized by air-fed tissue. The life of the forest, of the meadow, and of the mossy bank is drawn from the effulgence of the orb of day, for it is in the loom of the plant that the light of the sun is woven into life. For this light every plant struggles; toward the fountain every plant turns, that it may drink; aloft it lifts its head, higher and still higher above its fellows, and abroad it stretches its branches, and athwart the course of the sunbeams it spreads its leaves, that it may catch as much sunlight as it can. The plant that lifts widest, and clothes

its head highest, and spreads its limbs

itself with the densest verdure, is the successful competitor. Its

prosperity is its neighbors' adversity; its life is its neighbors' death. A shadow is the sword of a great tree, and with this weapon it slays a thousand. The life of one is the death of many. But those that drink from the fountain of life are the best of their race; those that are stricken with the shadow sword fall because they have less of plant excellence than their destroyer. It is a survival of the fittest; it is natural selection; it is evolution toward higher life.

Animals live on plants. They devour tissue and transmute vitality, and here the method of natural selection is reinforced. The sweetest and most nutritious plants become the food of animals; those that are bitter, those whose tissues are hard, those that are clothed with thorns, and those that secrete poisons, escape and live. So the plants that have killed their neighbors with shadow swords make defensive warfare on the animals that come to devour them; and the hard, the bitter, the stinging, and the poisonous are in the long run the successful competitors for life. The progress of the few is through the death of the many, and out of this progress are developed hardness, bitterness, piercing cruelty, and deadly poison. Time would fail to tell how plants bear flowers that ever become more graceful in form, more beautiful in color, and more delicious in perfume, through the agency of winged insects; how fruits become luscious and more luscious through the agency of birds of the air. But so it is. The tender and the hard grow on the same hillside, the beautiful and the ugly grow in the same forest, sweet odors and foul stenches arise from the same meadow, and salubrious and noxious fruits may be gathered from the same copse. The progress of the few is secured by the sacrifice of the many, and good and evil flourish in the same soil.

Turning to contemplate the evolution of animal life, we find facts of like character. If a barrel of oysters should be planted in an estuary of the sea and their progeny should all be preserved in successive generations for a decade, the oyster field thus produced would supply a bounteous repast for every man, woman, and child on the face of the earth. A multitudinous population is crowded into every possible region and place, and the fountains of life are ever flowing. A few may live, while

many must die. Besides the unconscious passive warfare of the plant, we thus have the designed and aggressive warfare of the animal, and all the world is at war. Air, earth, and sea are vast battlefields filled with animals large and small, flying through the air, prowling on the land, and swimming through the waters, on predatory forays—a world filled with all imaginary forms of life, all seeking whom they may devour. Those that fight best are saved; those that conceal themselves most deftly are preserved; those whose flight is most rapid reach protection. It is in this manner that many living beings are gradually furnished with defensive armor, and that defenseless beings grow sharp of vision, quick of hearing, and fleet of motion. Thus weapons of multitudinous forms are developed. Insects are provided with saws, knives, and stilettos; other creatures have teeth that pierce and cut and grind, and sharp beaks and talons and hoofs and tusks and horns; and some defend themselves with foul odors and deadly poisons. Strange, terrible, and loathsome are the many defensive and offensive devices of the animal world; and all these grow out of the struggle for existence. Competition among plants and animals is fierce, merciless, and deadly. Out of competition fear and pain are born; out of competition come anger and hatred and ferocity.. But it must not be forgotten that from this same competition arise things most beautiful and lovely, such as the wing of the butterfly, the plumage of the bird, the fur of the beast, the hum of the honey bee, the song of the nightingale, and the chatter of the squirrel. So good and evil dwell together.

The prodigality of life in the lower forms and the competition which arises therefrom, lead to two results, namely, the differentiation of co-ordinate species and the development of higher forms. These results combined are known as evolution. Germs of life are carried by wind and water, by animals themselves, and by other agencies, and are distributed wherever air may be wafted, wherever water may flow, wherever walking animals may go, wherever winged animals may fly, wherever creeping animals may crawl, and wherever finned animals may swim. The mountain, the hill, the plain, and the valley are thus perennially covered with germs, and the moor and the fen are abundantly

creeks, the rivers, the Seeds are carried even

supplied. The springs, the brooks, the lakes, and the seas are filled with germs. into most inhospitable places, such as caves and hot springs. Wherever they are carried they are developed, and gradually species are evolved adapted to all these varying environments. Thus arises a multiplicity of forms peculiar to the multiplicity of habitats. The mountain crag becomes the home of the dwarf, the opulent valley the home of the giant. The fiord has its denizens and the tropic sea its people. The rock is clothed with lichens and the ooze with moss. The sandy desert of the tropics has its fields of opuntia; the icy desert of the paleocrystic sea has its protococcus. In each habitat, by the death of those that fail in the struggle for existence, and by the preservation, from generation to generation, of those that develop the characteristics best adapted to environment, a serial progress is made. The new species developed have characteristics which constitute them higher beings in the scale of existence. These beings climb the ladder of life by rungs which, though separated by generations, are in fact so close together on the scale of progress that the minute degrees of evolution are indistinguishable when taken separately, and are only to be recognized in groups; as the motion of the hand on the dial is not marked by moments, but by hours. Yet germs and generations are plenty. Lives and years multiply, and all these bring the multiple changes which constitute transformation. By such processes of evolution species are differentiated and biotic life is developed.

The law of evolution which governs that mode of life called vitality," is denominated "the survival of the fittest in the struggle for existence." Under its sanction diverse species are developed. Most of such species make little or no progress; a smaller number develop a higher life; and an ever-diminishing number of species bourgeon and grow still higher and higher, until only a few reach exalted position, and man alone crowns the column. The great efficiency of the law of the survival of the fittest depends upon the enormous multiplicity of individuals, which causes them to compete for life. If the germs developed should not be more than equal to the duty of supplying the waste caused by death, the rate of progress would be greatly

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