Creation by Evolution/Evolution—Its Meaning
CREATION BY EVOLUTION
EVOLUTION—ITS MEANING
By David Starr Jordan
Chancellor Emeritus, Leland Stanford Junior University
Evolution as Orderly Change
By evolution, as the word is now used, we mean the universal process of orderly change. It includes cosmic changes in suns and planets and organic changes in living creatures, called organisms because they are made up of cooperating parts, or organs, which by fitting into one another constitute organization. And from the fact that all these changes—whether instantaneous, daily, yearly, or consuming centuries or æons, in the individual or in generations of individuals—are orderly, never random nor accidental, we derive our definition of evolution. Moreover, as this process occurs throughout all that we know, evolution becomes another name for Nature. Evolution, indeed, is Nature’s way; thus all Nature study, if serious and thorough, must lead to the recognition of evolution. That Nature has her ways is the most visibly evident fact in all our experience, and such phrases as “blind force” have no real meaning.
Nevertheless, the forces and conditions which surround suns and planets, or which mould mountains and seas, or which determine the formation of crystals or the accumulation of rocks, differ in certain ways from those which modify generations of life. We therefore usually treat orderly change in organized beings under a special head, that of organic evolution. For this a better term, bionomics, “‘life-ways,” has been suggested by Professor Patrick Geddes, of Edinburgh.
The theory of organic evolution is, in brief, that in our world no living thing and no succession of living things remain exactly the same for any period of time, long or short; and furthermore, to repeat, that all change is orderly, never the result of accident or caprice or favoritism. In Huxley's words: “Nothing endures save the flow of energy and the rational order that pervades it.”
As a science, organic evolution, or bionomics, comprises all that we know or that we may reasonably deduce from our actual knowledge of the history, development, and divergence of living creatures on the earth. It involves the idea of the “transmutation” of species (or kinds of animals or plants) through natural causes (there are no others), their characteristics varying for cause, with time and with space. To one having a fair knowledge of the facts concerned no different working hypothesis is now conceivable; and a working hypothesis becomes a part of science when every rival hypothesis has ceased to work.
The evidence for organic evolution is cumulative. All creatures show evidences of evolutionary processes, which are revealed on every hand. Now that we have in some degree the clue to life and reproduction, every plant, every animal, every man, every institution appears (in its degree) not alone as an argument for but as a demonstration of evolution. Demonstrations precede logic and stand above argument. No other type of evidence, moreover, is so convincing as the cumulative one. The question we are considering is not one of logic but one of fact. Logic, with its specialized branch, mathematics, adds nothing to our knowledge; its function is to clarify assumptions already accepted.
Accepting the fact of orderly change—universal in so far as we can trace the relations of cause and effect and of natural sequence—we face a more difficult problem: How are the changes brought about? Here we no longer find unanimity of opinion, for in the myriad of facts at our disposal no single man can master their prodigious range and their diverse aspects. A forest is not the same to a lumberman as to a landscape gardener. A primrose in a greenhouse is not the same as one by the river's brim. “The harvest of the quiet eye” is not that which is garnered by the reaper. The microscope and the telescope yield knowledge from different angles. But the lesson of all science is that whatever takes place in nature is natural; not “supernatural.” Indeed, to science “supernatural” is a meaningless word. It concerns either nothing at all or something not yet found out. We might say that the term “supernatural” can be applied only to a set of conceptions that are held by minds which have not learned that all facts of human experience are natural.
Much has been written as to the possible source of life in a lifeless world. It is easy to suppose some sort of “spontaneous generation” or “chemical transition.” That supposition follows the line of least resistance; it is said by some to be a “logical necessity.” Thus one sitting in his study may blithely construct “synthetic protoplasm” by “a juggling of words,” or by a combination of ideas drawn from physics and chemistry. To state facts in simple terms, life appears only in connection with carbon, oxygen, hydrogen, and nitrogen bathed in light, heat, water, and air. So we all admit. But all life, so far as we know, starts from life, and every living being had some sort of living ancestry, moulded by the shifting and sifting of environment.
As to the origin of life on the earth we know nothing whatever. Speculation about it is more or less futile; indeed it may be mischievous, as when some particular unproved suggestion serves as a basis for further philosophical expansion. Science must stop where the facts stop, or thereabout, the limit of "thereabout" covering all legitimate diversions and excursions of philosophy.
Volumes have been devoted to the evidence of evolution, but their value depends on no single fact nor on hundreds of facts. The inevitable conclusion is that all the facts point the same way. All the evidence, whether drawn from comparative anatomy, embryology, physiology, or geographical distribution, from human institutions or from human history, brings us to the same result. All of it deals with the same truth as seen from a thousand different sides. All life has its roots in the past and its fruitage in the future. We must view the millions of kinds of living beings not as disconnected entities resulting from disconnected acts of creation, but as divergent twigs from the great parent tree of life. In a large sense, there is, as Parker observes, "only one kind of life in our world."
"What we mean by life is protoplasmic organization. Just what this is, we do not know. . . . It is continuous and has been continuous since the remote past and will continue indefinitely in the future. Vitality is the activity of the organization. Death is not of necessity the cessation of vitality; death occurs only with the disintegration of the machine. When this occurs with any single organism acting as trustee for the specific organization, there are myriads of other trustees which will carry that organization on and into the future." [1]
The reality of evolution in organic life once admitted, the next step must be to trace the details of its operation. For we recognize no "law of evolution" as working without regard to conditions. Evolution in vacuo is a philosophic fancy. Conclusions resting on analogies, or on the juggling of words, are not a part of science. "Living organisms," says Dr. Osborn, "differ from lifeless mechanisms, no matter how perfect, in being more or less self-adapting, self-reforming, self-perfecting, self-regenerating, self-modifying, self-resourceful, self-experimental, self -creative." In other words, they possess—
- Individuality: No two organisms are exactly alike.
- Irritability: The response to external stimulus, every organism being either swayed by influences bearing upon it or else reacting against them. Through evolution this response rises by degrees to tropism — the tendency to react in a definite manner — and to reflex action, with its specialized derivatives, instinct and intelligence.
- Reproduction: The casting off of specialized cells, each one of which (usually united with its mate through amphimixis) initiates a new individual.
- Metabolism: The wearing away of tissues and their replenishment by food derived from the substance of other organisms, or from water and from air.
- Growth: The development in size and in specialization of the fertilized cell, which is followed by deterioration and death, except in one-celled organisms, where we have cell division instead of death.
- Evolution: Modification of traits from generation to generation through internal and external factors.
The evolution of living beings or the transmutation of species is conditioned by at least four influences, always present and continually acting on every individual, animal or plant. These moulding factors are heredity, variation, selection, segregation. A species, as properly defined, is a kind of animal or plant which during countless generations has undergone these influences in the open, has thus run the gauntlet of life, and has endured. A sheltered form, watched over in a greenhouse or a breeding pen, is not a genuine species; to become one it must hold its own and survive outside, in the stress of Nature. "The origin of species" therefore concerns the coöperation of tendencies inherent in the organism, these being diverted, modified, or directed by obstacles without.
Inherent tendencies may be summed up as heredity and variation. Heredity is the conservative influence, which unifies groups, limiting divergence; variation is a force creating divergence. Variation results from a complex series of influences, the most obvious and apparently the most important being the biparental factor—that is, sex. External influences, acting on the traits that distinguish species, by serving as obstacles to the even flow of heredity, are selection and isolation. Selection destroys unadapted individuals, and often, through them, the types or species they represent. Isolation, with its consequent segregation, or prevention of mass-breeding, leads to the separation of minor groups from the original stock by barriers, mainly but not wholly geographical. Selection fits all types to their environment; it enforces adaptation on all living beings but does not divide them into species. Segregation is the final moulder of species. No sound discussion of species as they exist in nature can ignore geography.
Two general facts relating to the origin of species are often disregarded by those who are engaged in experimental work. The first fact, just referred to, concerns the relation of forms to geographical conditions; the second fact is that related species seldom differ in any survival trait or character by which one is better fitted to live than another. The “survival of the fittest” is a process that operates within the species rather than between one group as a whole and another group. Most species have one or more twins or geminates, which differ in minor features and do not inhabit the same region. This rule of geminate species, accepted by the ornithologist Dr. Joel A. Allen and called by him “Jordan’s Law,” was stated by the present writer in 1904, as follows:
“Given any species in any region, the nearest related species is not likely to be found in the same region, nor in a remote region, but in a neighboring district, separated from the first by a barrier of some sort, or at least by a belt of country the breadth of which gives the effect of a barrier.”
Illustrations among plants, animals, races of men, and human speech appear on every hand. On either side of most barriers geminate species and subspecies (that is, species in the making) occur in every group of organisms, some so different as to require separate names, some barely distinguishable from their associates. Take those well-known birds the flickers, for instance. They belong to the genus Colaptes, a group of woodpeckers. On the east side of the Rocky Mountains we have the form called “yellow-hammer” (Colaptes auratus), with the shafts of its quills bright yellow. On the west side of the mountains we have the “red-shafted flicker” (Colaptes cafer), with the shafts of its quills bright red. These two species show also certain other slight differences, scarcely noticeable. On the other hand, the golden warbler, which ranges through the whole of the United States, migrating widely north and south as the seasons change, is all of one species, because everywhere it can breed freely with the mass of its kind.
Contrariwise, each island in the West Indies has its own peculiar species of warblers (Mniotiltidæ), whose migrations are not general but range simply between the mountains and the shore of the island. On the same principle and for the same reason, each island in the South Seas has its own peculiar dialect, each plainly derived, however, from the same ancestral language.
Again, each side of the isthmus of Panama, closed since Miocene time—two or more millions of years ago—has its geminate pairs of fishes, some six hundred in all, clearly defined, the distinctions being in traits as useless to the fish itself as to man. The temperate zone has its own series of forest trees, many of which are recognizable as geminates. The plane-tree, the elm, the elder, and the alder belt the earth, but with progressively changing species. In fact, in all groups the geminate relation becomes the rule, and a species absolutely isolated and unvarying is the exception.
These facts are too well-known to students of the geographical distribution of plants and animals to require elaboration here. It is therefore true, as already affirmed, that no theory of the origin of species can be sound if it fails to take geography into account.
Science and Faith
The Universe is with us. It is our Universe and we are part of it and have no alternative save to accept it as it is and as reverently as may be. The positive side of religion is the feeling of being at home in God's World. Whatever our conception of God the attitude remains. God's World is to us no alien land. It is our home and it has been the home of our ancestors for aeons immeasurable, so that our life is fairly adjusted to it in all its details. And the more thoroughly and widely we become acquainted with its make-up the less sympathy we can feel with those who would "remould it nearer to the heart's desire."
Science is verified knowledge. Little by little, through processes of induction, we establish a basis of fact which, when stated in terms of human experience, becomes truth. No human truth, however, is absolutely without error. Yet though all truth must remain in some degree incomplete, given time it gains both momentum and accuracy. With such progress, error and false deduction fall off on every side, usually without any possibility of revival.
The history of science is marked by constant collision between tradition and discovery. In the majority of men, ideas are controlled by custom or by desire; hence arises the process, almost inescapable, called by Dr. Conklin "thinking wishly." Our observations and experiments may be quite objective; our thought, perhaps, is never altogether so. Anthropomorphic tendencies spread through our philosophy and through all the minor affairs of life and form a constant obstruction to the spread of knowledge.
Yet despite all this, and despite all forms of human credulity, science has forced the civilized world to acknowledge a good many things not hoped for and often not desired. We now understand, for instance, that the stars are not pinholes in the celestial floor, through which rain drips upon us; that the sunset is not lighted by the red flames of hell into which the sun daily sinks; that planets are not carried back and forth by angels; that light and heat both come from the sun; that the earth is not the immovable center of the universe; that in the universe we can “see no trace of a beginning nor prospect of an end,” and that “time is as long as space is wide"; that the antipodes are really inhabited by real people; that 20,000 air breathing animals (outside of insects) could not foregather in pairs in the Ark; that fossils are relics of once-living creatures; that fossil shells are not evidence of the flood; that the Lord is not appeased by burnt offerings of lambs or of men; that lunatics are not possessed by devils nor yet struck by moonbeams; that the cure for scrofula is not found in the touch of a king; that no divinity indeed doth hedge a king, nor even the state; that a comet has its orbit and appears on its own business, not ours; that the penalty for wrong-doing is ours now and is within us; that ignorance and superstition are perilous guides for conduct; and that only Truth makes us free!
All our present conclusions concerning these matters and a thousand more are results of scientific research, not of religion as that word is commonly defined. To give one more example, however: Does any educated person now respect the dictum ascribed to Archbishop Ussher, who said, 200 years ago, that “Heaven and earth, center and circumference, were created all together at the same instant, with the clouds full of water, on October 24, 4004 B.C., at 9 o’clock in the morning?” And yet time was when to discredit this baseless pronouncement may have been held to cast one into outer darkness.
By the coöperation of observers and investigators much of the débris of our grandfather’s science has already been cleared away, and with it necessarily the preconception of a special creation of the myriads of species of animals and plants and the assumed chasm between humanity and our lowly mammalian brothers. The collision of ideas which progressive discoveries of truth have occasioned is not, however, strictly speaking, a “warfare of religion and science.” It is the inevitable struggle between tradition and knowledge, between conventional beliefs and new views demanded by new evidence. This conflict exists, not alone in church and state, but in the mind of every growing and forward-looking man.
The infinite expanse of the “unfathomed universe,” its development through countless periods of time, the boundless range of its changes and the rational order that pervades it, all seem to demand an infinite intelligence behind its manifestations. ‘That intelligence we cannot define, but of this we feel sure—it centers in no mere tribal god, nor one busy, man-fashion, with schemes and plans. Nor can it be one obsessed by human passions or jealousies. To thoughtful minds it becomes increasingly evident that the majestic mechanism of the universe and the perfect fitting of life to the earth on which it rests are no chance products of “fortuitous clashing of atoms.” We know no cosmic results brought about by accident, happy or unhappy. It has been said that the attributes of humanity are merely traits of “complex carbon compounds.” Even if true, this statement makes the facts no simpler, but far more complicated, by throwing on chemical reactions the brunt of the problems of life. So far as we can see, there is no “chaos” in the universe, nor was there ever any.
In the title of this symposium the word “creation” must be taken in its broadest sense as the aggregation of the intelligence and the energies which enter into the development of the Universe. Is not “‘creation by evolution” a far more exalted conception than any creation by fiat imagined of old? And does it not reveal a Godhead infinitely worthy of obedience and adoration?
Binds me to all that breathes; . . .
I am the child of earth and air and sea.
My lullaby by hoarse Silurian storms
Was chanted, and through endless changing forms
Of tree and bird and beast unceasingly
The toiling ages wrought to fashion me.
Of their great souls in mine, defying death
And change. I grow and blossom as the tree,
And ever feel deep-delving earthly roots
Binding me closely to the common clay;
Yet with its airy impulse upward shoots
My soul into the realms of light and day!
Hjalmar Hjorth Boyesen
REFERENCES
- Darwin, Charles. Origin of Species; Descent of Man.
- Guyer, Michael J. Being Well Born.
- Holmes, Samuel J. Life and Evolution; The Trend of the Race.
- Jennings, Herbert Spencer. Prometheus and other works.
- Jordan, D. S. The Factor of Isolation in the Formation of Species: Smithsonian Report of 1925. War and the Breed.
- Jordan, D. S., and Kellogg, Vernon. Evolution and Animal Life.
- Kellogg, Vernon. Beyond War.
- Kerr, J. Graham. Evolution.
- Newman, Horatio H. Evolution; Genetics and Eugenics.
- Nicoval, G. P. The Biology of War.
- Osborn, Henry Fairfield. From the Greeks to Darwin and numerous other books and papers.
- Osborn, Mrs. Lucretia Perry. The Chain of Life.
- Parker, Geo. H. What Evolution Is.
- Thomson, J. Arthur. The System of Animate Nature; Heredity in Relation to Eugenics, and other works.
- Ward, Henshaw. Evolution for John Doe. (Simple language and very clever.)
- Wiper, H. H. The Pedigree of the Human Race.