Natural Origin of Species. 255 Large and highly organised animals, though long lived as individuals, rarely live long specifically. The formation, according to law, of varieties and species from the common type of animal structure is called "the Natural Origin of Species." The dying of unfavourable and the continuance of favourable specimens are designated "Natural Selection." So far, every breeder of sheep and pigeon fancier agrees with the philosopher. The argument may be carried into the domain of plants and flowers. Stemleaves become sepals and petals; sepals and petals grow into stamens, nectaries, and ovaries; until the doctrine of the metamorphosis of plants stands complete. Of the forces evoked we know nothing; nor can we account for their supposed action in the constant introduction of new life-forms becoming more and more like those now in existence. As to those which are strictly species-" Each of them always remains separated from the others by an interval which nature cannot overstep." 'It is one of the clearest facts in the animal as in the vegetable world; all races gradually reproduce and perpetuate themselves without mingling or confounding one with the other." It is put yet more forcibly-" No race will amalgamate with another: they die out, or seem slowly to be becoming extinct." Professor Huxley states "To sum up our knowledge of the ethnological past of man; so far as the light is bright, it shows him substantially the same as now, and when it grows dim, it permits us to see no sign that he was other than he is now." 4 In the same address he says-" Admit that Negroes and Australians, Negritoes and Mongols are distinct species, a distinct genera, if you will, and you may yet, with perfect consistency, be the strictest of monogenists, and even believe in Adam and Eve as the primæval parents of all mankind." So we may say with Sir Charles Lyall "There is no valid objection to the doctrine of the human race springing from a single pair." 1 Isidore Geoffrey Saint-Hilaire "Histoire Naturelle Generale," iii. p. 210. Prichard "Natural History of Man,” i. p. 17. 366 Ethnological Journal," p. 98. "Method and Results of Ethnology." "Antiquity of Man," xx. p. 385. Goethe was the first, Professor Helmholtz says, 1 who laid down with precision and confidence, that all differences in the structure of animals must be looked upon as variations of a single primitive type, induced by the coalescence, the alteration, the increase, the diminution, or even the complete removal of single parts of the structure; the very principle, in fact, which has become the leading idea of comparative anatomy in its present stage. Mr. Darwin thinks "there is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one." 2 Professor Huxley says "All existing species are the result of the modification of pre-existing species, and those of their predecessors; and it is probable, though not a necessary consequence of this hypothesis, that all living creatures have arisen from a single stock. . . The vast series of extinct animals is not divisible, as it was once supposed to be, into distinct groups, separated by sharply marked boundaries. There are no great gulfs between epochs and formations-no successive periods marked by the appearance of plants, of water-animals, and of land animals en masse."s The theory of Lamarck groups organic matter under simple forms. Their first outlines, altered by time and circumstances, successively give birth to radiated creatures, to the inferior mollusks, to articulate animals, to the lowest fishes, then to man. "Exercising an organ, gains development and extension which insensibly change it, until it becomes wholly different. On the contrary, the faulty use of an organ impoverishes it gradually, and ends by destroying it." ceasing to fly, lose the power of flight. "This atrophy reaches its climax in the snakes. . . by the ribs and intercostal muscles having undertaken the work of the limbs."5 Mr. Owen writes "I am constrained by evidence to affirm that in the vertebrate, as in the invertebrate series, there is manifested a principle of development through polar relations, 1 Goethe's "Scientific Researches." "The Doctrine of Descent and Darwinism," Oscar Schmidt. Birds, Development. 257 working by repetition of act, and by multiplication of life parts, controlled by an opposite tendency to diversify the construction, and enrich it with all possible forms, proportions, and modifications of parts, conducive to the fulfilment of a pre-ordained purpose and a final aim; these opposite yet reciprocally complemental factors co-operating to the ultimate result, with different degrees of disturbance, yet without destruction of the evidence of the typical unity." Evidence may be multiplied to any extent. "Every cell, like every individual plant or animal, is the product of a previous organism of the same kind." "Unity of plan everywhere lies hidden under the mask of diversity of structure." In plainer words "To study the succession of animals in time, and their distribution in space, is to become acquainted with the ideas of God Himself."3 "There is," says Dr. Geo. Combe, "scarcely a single page in my three physiological works in which God was not present to my mind. I regard the whole laws of animal economy, and of the universe, as the direct dictates of the Deity; and in urging compliance with them, it is with the earnestness and reverence due to a Divine command that I do it. I almost lose the consciousness of self in the anxiety to attain the end, and when I see clearly a law of God in our own nature I rely upon its efficacy for good, with a faith and peace which no storm can shake." Life was evolved from no life-God evolved it; organisms from inorganic matter. Distinct provinces existed from the very earliest times; and whatever alterations arose, whether in plants or animals, seem to have been due to geographical and climatal conditions; not to automatism but by that energy of which all phenomena are manifestations. In some organisms there has been little or no change. The Globigerina, little builders of the vast chalk formations, were the same as those now found in the depths of the Atlantic Ocean; time has effected no change in them. The lizards of to-day are no better than those of the Permian period. The Labyrinthodonts cannot be rated under the living Salamander Anatomy of Vertebrates," Intr. p. xxi. : Richard Owen, M.A., F.R.S. "Comp. Physiol.," p. 347: Dr. Carpenter. "Prin. Zool.," c. xiv.: Agassiz. R and Triton. The Devonian Ganoids are near akin to Polypterus and to Lepidosiren. We are not warranted in asserting that the earlier types, so far as known, were more degraded, or embryonic, in structure than their modern representatives. A long winged bird will sometimes hatch a longer winged; a changing climate and variable conditions produce adaptations; where there is dry land not many aquatic creatures will be found; and those mechanical instruments, the hands of the ape, the hoofs of the horse, the fins of the whale, the trowels of the mole, and the wings of the bat, must obey the behests of animal will in their different elements; but that rumination will come to an animal through long sitting, or that wings, trowels, fins, hoof, hands are common property and interchangeable by animal will is not credible. Every life conditions its own form; and the power of adaptation, from within and from without, has reflex forcible action: but the so-called persistent types, both of animals and plants, have sustained very little apparent change from their first appearance to the present time. In those which are not persistent, there is a resemblance of arrangement, as also of order and character in the succession. The wonder is that the changes have been so small; not that they have been so great. The only safe and unquestionable testimony we can procure, fails to show positively "any sort of progressive modification towards a less embryonic, or less generalised type, in a great many groups of animals of long continued geological existence. In these groups there is abundant evidence of variation-none of what is understood as progression; and, if the well known geological record is to be regarded as even any considerable fragment of the whole, it is inconceivable that any theory of a necessarily progressive development can stand, for the numerous orders and families cited afford no trace of such a process." An impartial survey "An of ascertained truths negatives those doctrines of progressive modification which suppose a necessary progress from more to less embryonic forms, or from more to less generalised types. "If the carliest fossiliferous rocks now known are coeval with 1 "Persistent Types of Life :" Prof. Huxley. Embryonic Development. 259 the commencement of life, and if their contents give us any just conception of the nature and the extent of the earliest fauna and flora, the insignificant amount of modification which can be demonstrated to have taken place in any group of animals or plants, is quite incompatible with the hypothesis that all living forms are the results of a necessary process of progressive development; entirely comprised within the time represented by the fossiliferous rocks. Contrariwise, any admissible hypothesis of progressive modification must be compatible with persistence without progression, through infinite periods."1 With regard to the length of time claimed for development of the higher organisms: no such length is needed. The high and complicate human organism arises, in course of a few months, from a simple cellular state through many transformations; from a seed, like a plant, into structure and condition, like some of the lower fishes; thence, into amphibious kind; then, as a mammal; and by last progress of all—a man. The embryonic development is a rapid succession, in general outlines, of different and advancing forms; but there is not such exactness that the embryonic man is a plant, or a fish ; he is neither therefore, though these leading characteristics are said to require myriads of ages in the plant, and in the fish, the assertion that myriads of ages are required for the production of man through many bestial conditions, of beast through vegetable stages, and of the higher through lower vegetable organization, is unwarranted. Similarity of parts in organisms, and like phases in the embryonic state, are not proof of the universal evolution of higher from lower forms. As for man, the lower organisms are living figures of his every part and state. As for animal and vegetable characteristics, they so intermingle that in the lowest forms no separation seems to exist; nevertheless, an invisible essential difference does exist. In those organisms the Monera, Amaba, etc., which change their form every moment, we are as little able to point out a definite fundamental form; as we are to find it in shapeless, formless anorgana, such as non-crystallized stones: nevertheless, though "Persistent Types of Life :" Prof. Huxley. |