CHAPTER III
FOSSIL PEDIGREES
“By dint of such great efforts we succeeded only in piecing together genial romances more or less historical.”—B. Grassi, Prof. of Comparative Anatomy, Univ. of Rome, “La vita” (1906), p. 227.
§ 1. The Argument in the Abstract
The palæontological argument for evolution is based upon the observed gradual approximation in type of the earlier forms of life, as represented by the fossils still preserved in successive geological strata, to the later forms of life, as represented by the contemporary species constituting our present flora and fauna. Here the observed distribution in time supplements and confirms the argument drawn from mere structural affinity. Here we are no longer dealing with the spatial gradation of contemporary forms, arranged on a basis of greater or lesser similarity (the gradation whence the zoölogist derives his argument for evolution), but with a temporal gradation, which is simultaneously a morphological series and an historical record. The lower sedimentary rocks contain specimens of organic life very unlike modern species, but, the higher we ascend in the geological strata, the more closely do the fossil forms resemble our present organisms. In fact, the closeness of resemblance is directly proportional to the proximity in time, and this seems to create a presumption that the later forms of life are the modified descendants of the earlier forms. Considered in the abstract, at least, such an argument is obviously more formidable than the purely anatomical argument based on the degrees of structural affinity observable in contemporary forms. It ought, therefore, to be extremely persuasive, provided, of course, it proceeds in rigorous accord with indubitably established facts and rules out relentlessly the alloy of uncritical assumptions.
Here, likewise, we find the theory of transformism asserting its superiority over the theory of immutability, on the ground that evolutionism can furnish a natural explanation for the gradational distribution of fossil types in the geological strata, whereas the theory of permanence resorts, it is said, to a supernaturalism of reiterated “new creations” alternating with “catastrophic exterminations.” Now, if this claim is valid, and it can be shown conclusively that fixism is inevitably committed to a postulate of superfluously numerous “creations,” then the latter theory is shorn of all right to consideration by Occam’s Razor: Entia non sunt multiplicanda sine ratione. It is rather difficult to conceive of the Creator as continually blotting out, and rewriting, the history of creation, as ruthlessly exterminating the organisms of one age, only to repopulate the earth subsequently with species differing but little from their extinct predecessors—ad quid perditio haec? Such procedure hardly comports with the continuity, regularity and irrevisable perfection to be expected in the works of that Divine Wisdom, which “reacheth ... from end to end mightily and disposeth all things sweetly” (Wisdom, viii; 1), which “ordereth all things in measure, and number and weight.” (Wis. xi; 21.)
Following the lead of other evolutionists, Wasmann has striven to saddle fixism with the fatuity of periodic catastrophism and “creation on the installment plan.” But even Cuvier, who is credited with having originated the theory of catastrophism, did not go to the absurd extreme of hypothecating reiterated creations, but sought to explain the repopulation of the earth after each catastrophe by means of migrations from distant regions unaffected by the catastrophe. Historically, too, fixism has had its uniformitarian, as well as its catastrophic, versions. In fact, Huxley classifies both uniformitarianism and catastrophism as fixistic systems, when he says: “I find three more or less contradictory systems of geologic thought ... standing side by side in Britain. I shall call one of them Catastrophism, another Uniformitarianism, the third Evolutionism.” (“Lay Sermons,” p. 229.) Obviously, then, fixism is separable from the hypothesis of repeated catastrophes alternating with repeated “creations.” Stated in proper terms, it is at one with evolutionism in rejecting as undemonstrated and improbable the postulate of reiterated cataclysms. It freely acknowledges that, in the absence of positive evidence of their occurrence, the presumption is against extraordinary events, like wholesale catastrophes. It sanctions the uniformitarian tenet that ordinary cosmic processes are to be preferred to exceptional ones as a basis of geological explanation, and it repudiates as unscientific any recourse to the unusual or the miraculous in accounting for natural phenomena. Its sole point of disagreement with evolutionism is its refusal to admit organic changes of specific magnitude. It does, however, admit germinal changes of varietal magnitude. It also recognizes that the external characters of the phenotype are the joint product of germinal factors and environmental stimuli, and admits, in consequence, the possibility of purely somatic changes of considerable profundity being induced by widespread and persistent alterations in environmental conditions. Like Darwin, the uniformitarian fixist ascribes the origination of organic life to a single vivifying act on the part of the Creator, an act, however, that was formative rather than creative, because the primal forms of life, whether few or many, were all evolved through Divine influence from preëxistent inorganic matter. Unlike Darwin, he ascribes the continuation of organic life to generative processes that were univocal (generationes univocae), and not gradually-equivocal (generationes paulatim aequivocae). In the next chapter, we shall see that, in attributing the initial formation of species to a Divine act, neither Darwin nor the creationists exposed themselves to the charge of explaining the “natural” by means of the “miraculous.” And, as for the process by which living forms were continued upon earth, the univocal reproductive process upheld by fixism is more manifestly a natural process than the gradually-equivocal generation of variable inheritance hypothecated by the theory of transmutation. The sole matter of dispute between the two views is whether the life-cycles of organisms are circles or spirals.
But all this, it will be said, is purely negative. Merely to refrain from any recourse to the extraordinary or the supernatural is by no means sufficient. “Natural explanations” must be explanatory as well as natural. Unless there be a simplification, a reduction of plurality to unity, a resolution of many particular problems into a common general problem, we have no explanation worthy of the name. Granting, therefore, that uniformitarian fixism does not recur to the anomalous or the miraculous, it still lies open to the charge of failing in its function as an explanation, because it multiplies origins in both space and time. Transformism, on the contrary, is said to elucidate matters, inasmuch as it unifies origins spatially and temporally.
That transformism successfully plausibleizes a unification of origins in space, is true only in a limited and relative sense. The most that can be said for the assumption, that resemblances rest on the principle of common inheritance, is that it permits of a numerical reduction of origins, but this numerical reduction will, by an intrinsic necessity, always fall short of absolute unification. The monophyletic derivation of all organic forms from one primordial cell or protoblast is a fantastic dream, for which, from the very nature of things, natural science does not, and can not, furnish even the semblance of an objective basis. The ground is cut from under our feet, the moment we attempt to extend the principle of descent outside the limits of an organic phylum. The sole basis of inference is a group of uniformities, and, unless these uniformities predominate over the diversities, there can be no rational application of the principle of transformism. Hence, the hypothesis, that organisms are consanguineous notwithstanding their differences, loses all value as a solution at the point where resemblances are outweighed by diversities. The transmutation assumed to have taken place must be never so complete as to have obliterated all recognizable vestiges of the common ancestral type. “Whenever,” says Driesch, “the theory that, in spite of their diversities, the organisms are related by blood, is to be really useful for explanation, it must necessarily be assumed in every case that the steps of change, which have led the specific form A to become the specific form B, have been such as only to change in part that original form A. That is to say: the similarities between A and B must never be overshadowed by their diversities.” (“Science and Philosophy of the Organism,” v. I, p. 254.) When, therefore, the reverse is true and diversities are prevalent over uniformities, we are left without clue or compass in the midst of a labyrinth of innumerable possibilities. Such are the limits imposed by the very nature of the evidence itself, and the scientists, who transgress these limits, by attempting to correlate the primary phyla, are on a par with those unconvincible geniuses, who continually besiege the Patent Office with schemes ever new and weird for realizing the chimera of “perpetual motion.”
Thus scientific transformism is unable to simplify the problem beyond a certain irreducible plurality of forms, lesser only in degree than the plurality postulated by fixism. This being the case, the attempts of Wasmann and Dorlodot to prune the works of Creation with Occam’s Razor are not only presumptuous, but precarious as well. Qui nimis probat, nihil probat! If it be unworthy of God to multiply organic origins in space, then monophyletic descent is the only possible alternative, and polyphyletic transformism falls under the same condemnation as fixism. Yet the polyphyletic theory of descent is that to which both Wasmann and Dorlodot subscribe, as it is, likewise, the only kind of transformism which science can ever hope to plausibleize. Besides, too close a shave with Occam’s Razor would eliminate creation altogether, since all theologians cheerfully admit that it was the result of a free and unnecessary act on the part of God. When we apply our rationes convenientiae to the Divine operations, we must not make the mistake of applying them to the Divine action itself instead of the created effects of that action. We may be competent to discern disorder and irregularity in finite things, but we are wholly incompetent to prescribe rules for Divine conduct. To say that God is constrained by His infinite Wisdom to indirect, rather than direct, production, or that He must evolve a variety of forms out of living, rather than non-living, matter, is to be guilty of ridiculous anthropomorphism. There is no a priori reason, founded upon the Divine attributes, which restricts God’s creative action to the production of this, or that, number of primordial organisms, or which obliges him to endow primitive organisms with the power of transmutation.
But the fact that these rationes convenientiae fail to establish the a priori necessity of a unification of organic origins in space, does not imply that they are without value in suggesting the unification of organic origins in time. Order and regularity are not excluded by spatial multiplicity, but they may easily be excluded by the incongruities of an irregular succession of events. Indeterminism and chance are, indeed, inseparable from the course of Nature. There is in matter an unlimited potentiality, incommensurate with the limited efficacy of natural agencies. Hence it evades the absolute control of all finite factors and forces. But the anomalies and irregularities, which are contingent upon the limitation or frustration of second causes unable to impose an iron necessity upon evasive matter, are not referable to the First Cause, but rather to the finite efficacy of second causes. Such anomalies in natural processes, consequently, are not inconsistent with infinite wisdom and power on the part of the Creator. If, on the contrary, the anomaly occurs, not in the form of an accidental frustration of a natural agency, but in the form of an intrusive “new creation,” the irregularity in question would then be referable to the Creator Himself, and such derogations of order are inadmissible, except as manifestations of the supernatural. In fact, the abrupt and capricious insertion of a “new creation” into an order already constituted, say, for instance, the sudden introduction of Angiosperms in the Comanchian period, or of mammals in the Tertiary, would be out of harmony with both reason and revelation. Unless there is a positive reason for supposing the contrary, we must presume that, subsequent to the primordial constitution of things, the Divine influence upon the world has been concurrent rather than revolutionizing. Hence a theory of origins, compatible with the simultaneous “creation” of primal organisms, is decidedly preferable to a theory, which involves successive “creations” at random. That transformism dispenses with the need of assuming a succession of “creative” acts, is perfectly obvious, and, unless fixism can emulate its rival system in this respect, it cannot expect to receive serious attention.