# The Scientific Monthly/Volume 3

Index page: The Scientific Monthly_vol._3.djvu
The Scientific Monthly

## Volume III

THE SCIENTIFIC MONTHLY
EDITED BY J. McKEEN CATTELL
VOLUME III
JULY TO DECEMBER, 1916
NEW YORK THE SCIENCE PRESS 1916
Copyright, 1916
The Science Press
PRESS OF
THE NEW ERA PRINTING COMPANY
LANCASTER, PA.
THE ORIGIN AND EVOLUTION OF LIFE UPON THE EARTH
By Henry Fairfield Osborn COLUMBIA UNIVERSITY, AMERICAN MUSEUM OF NATURAL HISTORY
LECTURE I. PART I
Introduction
WE may introduce this great subject by putting to ourselves four leading questions: first, is life something new; second, is life evolution the same as stellar evolution; third, is there evidence that similar physico-chemical laws prevail in life and in lifeless evolution; fourth, are life forms the result of law or of chance?
First: does the origin of life represent the beginning of something new in the cosmos, or does it represent the continuation and evolution of forms of matter and energy already found in the earth, in the sun, and in the other stars? This is the first question which occurs to us, and it is one which has not yet been answered. The more traditional opinion is that something new entered this and possibly other planets with the appearance of life; this is also involved in all the older and newer hypotheses which group around the idea of vitalism or the existence of specific, distinctive and adaptive energies in living matter. The more modern scientific opinion is that life arose from a recombination of forces preexisting in the cosmos. To hold to this answer, that life does not represent the entrance either of a new form of matter or of a new series of laws but is simply another step in the general evolutionary process, is certainly consistent with the development of me​6 THE SCIENTIFIC MONTHLY
chanicfl^ physics and chemistry since the time of Newton and of evo* lutionary thought since Lamarck and Darwin.
Second : the second question relates to the exact significance of the term evolution when applied to lifeless and to living matter. Is the development of life evolutionary in the same sense or is it essentially different from that of the inorganic world? Let us critically examine this question by comparing the evolution of life with what is known of the evolution of matter^ of the evolution of the stars^ of the formation of the earth; in brief ^ of the comparative anatomy and physiology of the universe as developed in the preceding lectures of this course by Kuther- ford," Campbell,* and Chamberlin;' of the possible evolution of the chem- ical elements themselves from simpler forms, in passing from primitive nebulse through the hotter stars to the planets, as first pointed out by Clarke' in 1873, and by Lockyer in 1874.
Do we find a correspondence between the orderly development of the stars and the orderly development of life ? Do we observe in life a con- tinuation of processes which in general have given us a picture of the imiverse slowly cooling ofiE and running down; or, after hundreds of millions of years of more or less monotonous repetition of purely physico- chemical and mechanical reaction, do we find that electrons, atoms, and molecules break forth into new forms and manifestations of energy which appear to be "creative," conveying to our eyes at least the im- pression of incessant genesis of new combinations of matter, of energy, of form, of function, of character?
To our senses it seems as if the latter view were the correct one, as if something new had been breathed into the aging dust, as if the first appearance of life on this planet marked an actual reversal of the previ- ous order of things. Certainly the cosmic processes cease to run down and begin to build up, abandoning old forms and constructing new ones. Through these activities within matter in the living state the dying earth, itself a mere cinder from the sun, develops new chemical com- pounds; the chemical elements of the ocean are enriched from new sources of supply, as additional amounts of chemical compounds, pro- duced by organisms from the soil or by elements in the earth that were not previously dissolved, are liberated by life processes and ultimately carried out to sea; the very composition of the rocks is changed; a new life crust begins to cover the earth and to spread over the bottom of the sea. Thus our old inorganic planet is reorganized, and we see in living matter a reversal of the melancholy conclusion reached by Campbell^ that
sButherford, Sir Ernest, 1914.
«CampbeU, William Wallace, 1914.
Chamberlin Thomas Chrowder, 1916.
* Clarke, P. W., 1873, p. 323.
7 GampbeU, William Wallace, 1915, p. 209.
�� � ​THE EVOLUTION OF LIFE 7
Ererythiiig in nature is gro^wing older and changing in eondition; slowlj or rapidly, depending npon circumstances; the meteorological elements and gravita- tion are tearing down the high places of the earth; the eroded materials are transported to the bottoms of valleys, lakes and seas; and these results beget farther consequences.
Thus, in answer to our second question, it certainly appears that living matter does not follow the old evolutionary order but represents a new assemblage of energies and new types of action, reaction, and interaction — ^to use the terms of Newton — ^between those chemical ele- ments which are as old as the cosmos itself, unless they prove to repre- sent, as Clarke, Lockyer, and Butherford have suggested, an evolution from still simpler elements.
Third, is there a continuation of the same physico-chemical laws? Yes, so far as we observe, the process is still evolutionary rather than creativBj because all these new characters and forms invariably arise out of new combinations of preexisting matter and appear to broadly conform to the laws of thermodynamics, and especially to Newton's third law. According to the interpretation by Pupin of this third law of Newton, action and reaction refer to what is going on be- tween material parts in actual contact, whereas interaction refers to what is going on between two material parts which are connected with each other by other parts. Action and reaction are simultaneous, whereas interaction refers to an action and reaction which are not simul- taneous. For example, when one pulls at a line the horse feels it a little later than the moment at which the line is pulled ; there is interaction between the hand and the horse's mouth, the line being the interconnect- ing part.
In this lecture I shall attempt to show that since in their simple forms living processes are known to be physico-chemical and are more or less clearly interpretable in terms of action, reaction and interaction, we are compelled to believe that complex forms will also prove to be interpretable in the same terms.
If we affirm that the entire trend of our observation is in the direc- tion of the physico-chemical rather than of the vitalistic hypotheses this is very far from affirming that the explanation of life is purely materialistic or that any present physico-chemical explanation is either final or satisfying to our reason. Chemists and biological chemists have very much more to discover. May there not be in the assemblage of cosmic chemical elements necessary to life, which we shall distinguish as the "life elements/^ some Jcnown element which thus far has not be- trayed itself in chemical analysis? This is not impossible, because a known element like radium, for example, might well be wrapped up in living matter but as yet undetected, owing to its suffusion or presence in excessively small quantities or to its possession of qualities that have escaped notice. Or, again, an unknown chemical element, to which the
�� � ​8 THE SCIENTIFIC MONTHLY
hypothetical term bion might be given, may lie awaiting discovery within this complex of known elements. Or an unknown source of energy may be active here. Or, as is far more probable from our present state of knowledge, unknown principles of action, reaction and interaction may await discovery: such principles are indeed adumbrated in the as yet partially explored activities of the catalytic agents in living chemical compoimds.
In answer to our first main question, to which we now return, we may express as our own opinion, based upon the logical application of uniformitarian evolutionary principles, that when life appeared some energies preexisting in the cosmos were brought into relation with the elements or forces already existing. In other words, since every advance thus far in the quest as to the nature of life has been in the direction of a physico-chemical rather than a vitalistic explanation, from the time when Lavoisier (1743-1794) put the life of plants on a solar-chemical basis, logically following the same direction, we believe that the last step into the unknown — one which possibly may never be taken by man — will also be physico-chemical in all its measurable and observable prop- erties, and that the origin of life, as well as its development, will ulti- mately prove to be a true evolution within the preexisting cosmos.
None the less, such evolution, we repeat with emphasis, is not like that of the chemical elements or of the stars; the evolutionary process now takes an entirely new and different direction. Although it arises through combinations of preexisting energies it is essentially construc- tive and creative; it is continually giving birth to an infinite variety of new forms and functions which never appeared in the universe before. While this creative power is something new derived from the old, it presents the first of the numerous contrasts between the living and the lifeless world.
We are now prepared for the fourth of our leading questions. It having been determined that the evolution of non-living matter follows certain physical laws and that the living world conforms to many if not to all of these laws the final question which arises is : does the living world also conform to law in its most important aspect, namely, that of fitness or adaptation, or does law emerge from chance?
Let us first make clear the distinction between law and chance. On this a physicist (M. I. Pupin) observes:
In physics, when diBtingrulshing between law and chance, we speak of co- ordinated phenomena like planetary motions, and of nan-coordinated phenomena like the motion of individual molecnles in a large number of molecules. In re- gard to such motion, chance or probability or so-called statistical modes of procedure guide the reasoning. Again, radiation is a statistical or non-coordi- nated mode of procedure, and sin^ it is closely related to the growth of plants (the simplest forms of life) why is not life in its constituent elements a statis- tical or chance procedure? May not life-forms and life itself be differentiated just like the motion of radiating atoms and observable forms of radiation f
�� � ​THE EVOLUTION OF LIFE 9
Although the motions giving riae to radiation are haphazard, the resulting forms of radiation which we observe are definite and beautifully arranged as if they proeeeded from perfectly coordinated and not from perfectly haphazard motions.
It is obvious that the answer to these questions put by a physicist may be reached in biology through observation.
Campbell has described the orderly development of the stars and Chamberlin the orderly development of the earth: is there also an orderly development of life? Are life forms, like celestial forms, the result of law or are they the result of chance? Thia is perhaps the very oldest biologic question that has entered the human mind, and it is one on which the widest difference of opinion exists even to-day.
Chance has been the opinion held by a great line of philosophers from Democritus and Empedocles to Darwin, and including Poulton, de Vries, Bateson, and many others of our own day : chance is the very eesence of the Darwinian selection hypothesis of evolution. William James' and many other eminent philosophers have adopted the ^' chance ^^ view as if it had been actually demonstrated, instead of being, as it is, one of the string of hypotheses upon which Darwin hung his theory of the origin of adaptations and of species. To quote the opinion of a recent writer:
And why not? Nature has always preferred to work by the hit or miss methods of chance. In biological evolution millions of variations have been produced that one useful one might occur.*
I have long maintained that this opinion is a biological dogma^® which has gained credence through constant reiteration, for I do not know that it has ever been demonstrated through the actual observa- tion of any evolutionary series.
Load has been the opinion of another school of natural philosophers, headed by Aristotle, the opponent of Democritus and Empedocles. This opinion has fewer philosophical and scientific adherents ; yet Eucken,*^ following Schopenhauer, has recently expressed it as follows :
From the very beginning the predominant philosophical tendency has been against the idea that all the forms we see around us have come into existence solely through an accumulation of accidental individual variations, by the mere blind concurrence of these variations and their actual survival, without the operation of any inner law. Natural science, too, has more and more demon- strated its inadequacy.
Unlike our first question as to whether the principle of life intro- duced something new in the cosmos, a question which is still in the stage of pure speculation, this fourth question of law versus chance in the
8 James, William, 1902, pp. 437-439.
* Davies, G. B., 1916, p. 583.
10 Biology like theology has its dogmas. Leaders have their disciples and blind followers. All great truths, like Darwin's law of selection, acquire a momentum which sustains half-truths and pure dogmas.
II Eueken, Budolf , 1912, p. 257.
* ↑ Fourth course of lectures on the William Ellery Hale Foundation, National Academy of Sciences, delivered at the meeting of the academy at Washington, on April 17 and 19, 1916. The author is greatly indebted for many notes and suggestions in physics and chemistry to his colleagues in the National Academy and Columbia University, especially to M. I. Pupin, F. W. Clarke, G. F. Becker and W. J. Gies.
* ↑ In order to consider this problem from a fresh, unbiased, and original point of view the author has purposely refrained from reading the recent treatises of Shafer, Moore and others on the origin of life. In the chemical section the author is, however, indebted to the very suggestive work of Henderson entitled "The Fitness of the Environment."