SIR RICHARD OWEN
Sir Richard Owen, the great naturalist, was born July 20, 1804, at Lancaster, England, and received his early education at the grammar school of that town. Thence he went to Edinburgh University. In 1826 he was admitted a member of the English College of Surgeons, and in 1829 was lecturing at St. Bartholomew's Hospital, London, where he had completed his studies. His "Memoir on the Pearly Nautillus," published in 1832, placed him, says Huxley, "at a bound in the front rank of anatomical monographers," and for sixty-two years the flow of his contributions to scientific literature never ceased. In 1856 he was appointed to take charge of the natural history departments of the British Museum, and before long set forth views as to the inadequacy of the existing accommodation, which led ultimately to the foundation of the buildings now devoted to this purpose in South Kensington. Owen died on December 18, 1892. His great book, "Comparative Anatomy and Physiology of the Vertebrates," was completed in 1868, and since Cuvier's "Comparative Anatomy," is the most monumental treatise on the subject by any one man. Although much of the classification adopted by Owen has not been accepted by other zoologists, yet the work contains an immense amount of information, most of which was gained from Owen's own personal observations and dissections.
I.—Biological Questions of 1830
At the close of my studies at the Jardin des Plantes, Paris, in 1831, I returned strongly moved to lines of research bearing upon the then prevailing phases of thought on some biological questions.
The great master in whose dissecting rooms I was privileged to work held that species were not permanent as a fact established inductively on a wide basis of observation, by which comparative osteology had been created. Camper and Hunter suspected the species might be transitory; but Cuvier, in defining the characters of his anaplotherium and palæotherium, etc., proved the fact. Of the relation of past to present species, Cuvier had not an adequate basis for a decided opinion. Observation of changes in the relative position of land and sea suggested to him one condition of the advent of new species on an island or continent where old species had died out. This view he illustrates by a hypothetical case of such succession, but expressly states: "I do not assert that a new creation was necessary to produce the species now existing, but only that they did not exist in the same regions, and must have come from elsewhere." Geoffrey Saint Hilaire opposed to Cuvier's inductive treatment of the question the following expression of belief: "I have no doubt that existing animals are directly descended from the animals of the antediluvian world," but added, "it is my belief that the season has not yet arrived for a really satisfying knowledge of geology."
The main collateral questions argued in their debates appeared to me to be the following:
Unity of plan or final purpose, as a governing condition of organic development?
Series of species, uninterrupted or broken by intervals?
Extinction, cataclysmal or regulated?
Development, by epigenesis or evolution?
Primary life, by miracle or secondary law?
Cuvier held the work of organisation to be guided and governed by final purpose or adaptation. Geoffrey denied the evidence of design and contended for the principle which he called "unity of composition," as the law of organisation. Most of his illustrations were open to the demonstration of inaccuracy; and the language by which disciples of the kindred school of Schelling illustrated in the animal structure the transcendental idea of the whole in every part seemed little better than mystical jargon. With Cuvier, answerable parts occurred in the zoological scale because they had to perform similar functions.
As, however, my observations and comparisons accumulated, they enforced a reconsideration of Cuvier's conclusions. To demonstrate the evidence of the community of organisation I found the artifice of an archetype vertebrate animal essential; and from the demonstration of its principle, which I then satisfied myself was associated with and dominated by that of "adaptation to purpose," the step was inevitable to the conception of the operation of a secondary cause of the entire series of species, such cause being the servant of predetermining intelligent will.
But besides "derivation" or "filiation" another principle influencing organisation became recognisable, to which I gave the name of "irrelative repetition," or "vegetative repetition." The demonstrated constitution of the vertebrate endoskeleton as a series of essentially similar segments appeared to me to illustrate the law of irrelative repetition.
These results of inductive research swayed me in rejecting direct or miraculous creation, and in recognising a "natural law or secondary cause" as operative in the production of species "in orderly succession and progression."
II.—Succession of Species, Broken or Linked?
To the hypothesis that existing are modifications of extinct species, Cuvier replied that traces of modification were due from the fossil world. "You ought," he said, "to be able to show the intermediate forms between the palæotherium and existing hoofed quadrupeds."
The progress of palæontology since 1830 has brought to light many missing links unknown to the founder of the science. The discovery of the remains of the hipparion supplied one of the links required by Cuvier, and it is significant that the remains of such three-toed horses are found only in deposits of that tertiary period which intervene between the older palæotherian one and the newer strata in which the modern horse first appears to have lost its lateral hooflets.
The molar series of the horse includes six large complex grinders individually recognisable by developmental characters. The representative of the first premolar is minute and soon shod. Its homologue in palæotherium is functionally developed and retained, that type-dentition being adhered to. In hipparion this tooth is smaller than in palæotherium, but functional and permanent. The transitory and singularly small and simple denticle in the horse exemplifies the rudiment of an ancestral structure in the same degree as do the hoofless splint-bones; just as the spurious hoofs dangling therefrom in hipparion are retained rudiments of the functionally developed lateral hoofs in the broader foot of palæotherium.
Other missing links of this series of species have also been supplied.
How then is the origin of these intermediate gradations to be interpreted? If the alternative—species by miracle or by law—be applied to palæotherium, paloplotherium, anchitherium, hipparion, equus, I accept the latter without misgiving, and recognise such law as continuously operative throughout tertiary time.
In respect to its law of operation we may suppose Lamarck to say, "as the surface of the earth consolidated, the larger and more produced mid-hoof of the old three-toed pachyderius took a greater share in sustaining the animal's weight; and more blood being required to meet the greater demand of the more active mid-toe, it grew; whilst, the side-toes, losing their share of nourishment and becoming more and more withdrawn from use, shrank"—and so on. Mr. Darwin, I conceive, would modify this by saying that some individuals of palæotherium happening to be born with a larger and longer middle toe, and with shorter and smaller side-toes, such variety was better adapted to prevailing altered conditions of the earth's surface than the parental form; and so on, until finally the extreme equine modifications of foot came to be "naturally selected." But the hypothesis of appetency and volition, as of natural selection, are less applicable, less intelligible, in connection with the changes in the teeth.
I must further observe that to say the palæotherium has graduated into equus by "natural selection" is an explanation of the process of the same kind and value as that by which the secretion of bile was attributed to the "appetency" of the liver for the elements of bile. One's surprise is that such explanatory devices should not have died out with the "archeus faber," the "nisus formations," and other self-deceiving, world-beguiling simulacra of science, with the last century; and that a resuscitation should have had any success in the present.
What, then, are the facts on which any reasonable or intelligible conception can be formed of the mode of operation of the derivative law exemplified in the series linking on palæotherium to equus? A very significant one is the following. A modern horse occasionally comes into the world with the supplementary ancestral hoofs. From Valerius Maximus, who attributes the variety to Bucephalus downwards, such "polydactyle" horses have been noted as monsters and marvels. In one of the latest examples, the inner splint-bone, answering to the second metacarpal of the pentadactyle foot, supported phalanges and a terminal hoof resembling the corresponding one in hipparion. And the pairing of horses with the meterpodials bearing, according to type, phalanges and hoofs might restore the race of hipparions.
Now, the fact suggesting such possibility teaches that the change would be sudden and considerable; it opposes the idea that species are transmuted by minute and slow degrees. It also shows that a species might originate independently of the operation of any external influence; that change of structure would precede that of use and habit; that appetency, impulse, ambient medium, fortuitous fitness of surrounding circumstances, or a personified "selecting nature" would have had no share in the transmutative act.
Thus I have been led to recognise species as exemplifying the continuous operation of natural law, or secondary cause; and that not only successively but progressively; "from the first embodiment of the vertebrate idea under its old ichthyic vestment until it became arrayed in the glorious garb of the human form."
III.—Extinction—Cataclysmal or Regulated
If the species of palæothere, paloplothere, anchithere, hipparion, and horse be severally deemed due to remotely and successively repeated acts of creation; the successive going out of such species must have been as miraculous as their coming in. Accordingly, in Cuvier's "Discourse on Revolutions of the Earth's Surface" we have a section of "Proofs that these revolutions have been numerous," and another of "Proofs that these revolutions have been sudden." But as the discoveries of palæontologists have supplied the links between the species held to have perished by the cataclysms, so each successive parcel of geological truth has tended to dissipate the belief in the unusually sudden and violent nature of the changes recognisable in the earth's surface. In specially directing my attention to this moot point, whilst engaged in investigations of fossil remains, I was led to recognise one cause of extinction as being due to defeat in the contest which the individual of each species had to maintain against the surrounding agencies which might militate against its existence. This principle has received a large and most instructive accession of illustrations from the labours of Charles Darwin; but he aims to apply it not only to the extinction but to the origin of species.
Although I fail to recognise proof of the latter bearing of the battle of life, the concurrence of so much evidence in favour of extinction by law is, in like measure, corroborative of the truth of the ascription of the origin of species to a secondary cause.
What spectacle can be more beautiful than that of the inhabitants of the calm expanse of water of an atoll encircled by its ring of coral rock! Leaving locomotive frequenters of the calcarious basin out of the question, we may ask, Was direct creation after the dying out of its result as a "rugose coral" repeated to constitute the succeeding and superseding "tabulate coral"? Must we also invoke the miraculous power to initiate every distinct species of both rugosa and tabulata? These grand old groups have had their day and are utterly gone. When we endeavour to conceive or realise such mode of origin, not of them only but of their manifold successors, the miracle, by the very multiplication of its manifestations, becomes incredible—inconsistent with any worthy conception of an all-seeing, all-provident Omnipotence.
Being unable to accept the volitional hypothesis (of Lamarck) or the selective force exerted by outward circumstances (Darwin), I deem an innate tendency to deviate from parental type, operating through periods of adequate duration, to be the most probable way of operation of the secondary law whereby species have been derived one from another.
According to my derivative hypothesis a change takes place first in the structure of the animal, and this, when sufficiently advanced, may lead to modifications of habits. But species owe as little to the accidental concurrence of environing circumstances as kosmos depends upon a fortuitous concourse of atoms. A purposive route of development and change of correlation and inter-dependence, manifesting intelligent will, is as determinable in the succession of races as in the development and organisation of the individual.
Derivation holds that every species changes in time, by virtue of inherent tendencies thereto. Natural selection holds that no such change can take place without the influence of altered external circumstances educing or eliciting such change.
Derivation sees among the effects of the innate tendency to change, irrespective of altered surrounding circumstances, a manifestation of creative power in the variety and beauty of the results; and, in the ultimate forthcoming of a being susceptible of appreciating such beauty, evidence of the preordaining of such relation of power to the appreciation. Natural selection acknowledges that if power or beauty, in itself, should be a purpose in creation, it would be absolutely fatal to it as a hypothesis.
Natural selection sees grandeur in the "view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one." Derivation sees, therein, a narrow invocation of a special miracle and an unworthy limitation of creative power, the grandeur of which is manifested daily, hourly, in calling into life many forms, by conversion of physical and chemical into vital modes of force, under as many diversified conditions of the requisite elements to be so combined.
Natural selection leaves the subsequent origin and succession of species to the fortuitous concurrence of outward conditions; derivation recognises a purpose in the defined and preordained course, due to innate capacity or power of change, by which homogeneously-created protozoa have risen to the higher forms of plants and animals.
The hypothesis of derivation rests upon conclusions from four great series of inductively established facts, together with a probable result of facts of a fifth class; the hypothesis of natural selection totters on the extension of a conjectural condition explanatory of extinction to the origination of species, inapplicable in that extension to the majority of organisms, and not known or observed to apply to the origin of any species.
IV.—Epigenesis or Evolution?
The derivative origin of species, then, being at present the most admissible one, and the retrospective survey of such species showing convergence, as time recedes, to more simplified or generalised organisations, the result to which the suggested train of thought inevitably leads is very analogous in each instance. If to kosmos or the mundane system have been allotted powers equivalent to the development of the several grades of life, may not the demonstrated series of conversions of force have also included that into the vital form?
In the last century, physiologists were divided as to the principle guiding the work of organic development.
The "evolutionists" contended that the new being preexisted in a complete state of formation, needing only to be vivified by impregnation in order to commence the series of expansions or disencasings, culminating in the independent individual.
The "epigenesists" held that both the germ and its subsequent organs were built up of juxtaposed molecules according to the operation of a developmental force, or "nisus formations."
At the present day the question may seem hardly worth the paper on which it is referred to. Nevertheless, "pre-existence of germs" and evolution are logically inseparable from the idea of species by primary miraculously-created individuals. Cuvier, therefore, maintained both as firmly as did Haller. In the debates of 1830 I remained the thrall of that dogma in regard to the origin of single-celled organisms whether in or out of body. Every result of formfaction, I believed, with most physiologists, to be the genetic outcome of a pre-existing "cell." The first was due to miraculous interposition and suspension of ordinary laws; it contained potentially all future possible cells. Cell-development exemplified evolution of pre-existing germs, the progeny of the primary cell. They progagated themselves by self-division, or by "proliferation" of minutes granules or atoms, which, when properly nourished, again multiplied by self-division, and grew to the likeness of the parent cells.
It seems to me more consistent with the present phase of dynamical science and the observed graduations of living things to suppose the sarcode or the "protogenal" jelly-speck should be formable through the concurrence of conditions favouring such combination of their elements, and involving a change of force productive of their contractions and extensions, molecular attractions, and repulsions—and the sarcode has so become, from the period when its irrelative repetitions resulted in the vast indefinite masses of the "eozoon," exemplifying the earliest process of "formification" or organic crystallisation—than that all existing sarcodes or "protogenes" are the result of genetic descent from a germ or cell due to a primary act of miraculous interposition.
I prefer, while indulging in such speculations, to consider the various daily nomogeneously developed forms of protozoal or protistal jellies, sarcodes, and single-celled organisms, to have been as many roots from which the higher grades have ramified than that the origin of the whole organic creation is to be referred, as the Egyptian priests did that of the universe, to a single egg.
Amber or steel, when magnetised, seem to exercise "selection"; they do not attract all substances alike. A speck of protogenal jelly or sarcode, if alive, shows analogous relations to certain substances; but the soft yielding tissue allows the part next the attractive matter to move thereto, and then, by retraction, to draw such matter into the sarcodal mass, which overspreads, dissolves, and assimilates it. The term "living" in the one case is correlative with the term "magnetic" in the other. A man perceives ripe fruit; he stretches out his hand, plucks, masticates, swallows, and digests it.
The question then arises whether the difference between such series of actions in the man and the attractive and assimilative movement of the amæba be greater or less than the difference between these acts of the amæba and the attracting and retaining acts of the magnet.
The question, I think, may be put with some confidence as to the quality of the ultimate reply whether the amæbal phenomena are so much more different, or so essentially different, from the magnetic phenomena than they are from the mammalian phenomena, as to necessitate the invocation of a special miracle for their manifestation. It is analogically conceivable that the same cause which has endowed His world with power convertible into magnetic, electric, thermotic and other forms or modes of force, has also added the conditions of conversion into the vital force.
From protozoa or protista to plants and animals the graduation is closer than from magnetised iron to vitalised sarcode. From reflex acts of the nervous system animals rise to sentient and volitional ones. And with the ascent are associated brain-cells progressively increasing in size and complexity. Thought relates to the "brain" of man as does electricity to the nervous "battery" of the torpedo; both are forms of force and the results of action of their respective organs.
Each sensation affects a cerebral fibre, and, in so affecting it, gives it the faculty of repeating the action, wherein memory consists and sensation in a dream.
If the hypothesis of an abstract entity produces psychological phenomena by playing upon the brain as a musician upon his instrument be rejected, and these phenomena be held to be the result of cerebral actions, an objection is made that the latter view is "materialistic" and adverse to the notion of an independent, indivisible, "immaterial," mental principle or soul.
But in the endeavour to comprehend clearly and explain the functions of the combination of forces called "brain," the physiologist is hindered and troubled by the views of the nature of those cerebral forces which the needs of dogmatic theology have imposed on mankind. How long physiologists would have entertained the notion of a "life," or "vital principle," as a distinct entity if freed from this baneful influence may be questioned; but it can be truly affirmed that physiology has now established and does accept the truth of that statement of Locke—"the life, whether of a material or immaterial substance, is not the substance itself, but an affection of it."