The Old Riddle And The Newest Answer Part 13

It is most important to recollect that on evolutionary principles the first representatives of any such cla.s.ses--and the same holds of animals as well--must have been generalized forms, representing the type in the rough, or, in Mr. Herbert Spencer's phrase, exhibiting by comparison with their successors indefinite incoherent h.o.m.ogeneity, as contrasted with definite coherent heterogeneity. They should bear the same sort of relation to the finished articles worked up by Evolution as did the first bone-shaker bicycle to our latest patterns, or the news-sheets of Cromwell's time to the _Times_ or _Graphic_ of to-day. On this, as we saw in the last chapter, Mr. Darwin strongly insists, confessing at the same time that the Geological record alone can establish such progress as a fact.

How these various cla.s.ses of plants appear actually to have come upon the scene, Mr. Carruthers relates both in the paper from which we have just quoted, and at greater length in the address which he delivered as President of the Geologists' a.s.sociation,[251] to the following effect.

In the first place, he declares that although the geological record, at least as known to us, is very imperfect, and represents only an insignificant fragment of plant-history,

There is a large series of plant-remains completely and accurately known which supply a fair representation of the great events of plant-life that have taken place on the earth since Palaeozoic times. And these are more than sufficient to establish or destroy this hypothesis [of genetic evolution] by their testimony.

There is--he goes on to say--indirect evidence of the existence of vegetable life, long before we find any actual remains. Such indirect evidence is afforded in the first place by the abundance during this period of animal life, needing plants for its sustenance, and secondly by the enormous quant.i.ty of carbon in the rocks, which must have been secreted from the atmosphere by vegetable tissues. There are also certain surface marks or impressions occasionally to be found, which are probably due to plants of a soft and perishable character like the cellular cryptogams, and which although extremely vague and undefined, at least do not contradict the evolutionist, who regards them as evidence that the _Algae_ were, as according to him they ought to have been, the primeval plants. Mr. Carruthers adds a caution however, which can find its application in other instances as well:

While making this admission in relation to the vegetation of these older rocks, I must protest against the practice of completing the record of life forms, by filling in particular groups without any authority except the writer's impression of an adopted hypothesis, and then basing arguments on these a.s.sumptions in support of the hypothesis which created them. So completely has

VEGETABLE DEVELOPMENT.

+----------------------------------------------------+ Post Tertiary. +----------------------------------------------------+ Tertiary. { Pliocene. +----------------------------------------------------+ { Miocene. +----------------------------------------------------+ { Eocene. +----------------------------------------------------+ Secondary. { Chalk. Dicotyledons (Apetalae, Polypetalae, { Sympetalae). +----------------------------------------------------+ { Oolite. +----------------------------------------------------+ { Trias. +----------------------------------------------------+ { Permian. +----------------------------------------------------+ { Carboniferous. Monocotyledons. +----------------------------------------------------+ { { Devonian, or Clubmosses, Horsetails, Ferns, { Old Red Gymnosperms. { Sandstone. +----------------------------------------------------+ Primary. { Silurian. } Cellular Cryptogams. { Cambrian. } +----------------------------------------------------+ { Huronian. } Indications of Plants, { Laurentian. } not determinable. +===================+================================+ AZOIC.

phylogenetic [or racial] evolution become the creed of some leading naturalists that they unwittingly proceed in this manifestly unphilosophical method. But it is a first axiom, though one often forgotten, in this as in every scientific enquiry, that no step can be made in advance which is not based on fact.

After this initial stage, the story becomes much clearer, and at the same time less easy to reconcile with evolutionary requirements.

Instead of making their appearance singly and successively, and pa.s.sing imperceptibly one into another, all three groups of Vascular Cryptogams, and the Gymnosperms into the bargain, come on the stage together, in the Devonian strata; and Monocotyledons in the lower Carboniferous immediately following. There is no trace whatever of the development of any of these forms from the earlier cellular cryptogams:

But [says Mr. Carruthers] the evolution of the Vascular Cryptogams, and the Phanerogams, from the green seaweeds, through the liverworts and mosses, if it took place, must have been carried on through a long succession of ages, and by an innumerable series of advancing steps; and yet we find not a single trace either of the early water forms or of the later and still more numerous dry-land forms. The conditions that permitted the preservation of the fucoids in the Llandovery rocks at Malvern, and of similar cellular organisms elsewhere, were, at least, fitted to preserve _some_ record of the necessarily rich floras, if they existed, which through immense ages, led by minute steps to the Conifer [_Gymnosperm_] and Monocotyledon of these Palaeozoic Rocks.

Further, these earliest plants are not generalized forms of the various tribes to which they belong, but they are as highly specialized as any subsequent representatives of the particular group to which they belong, and wherever they differ from later plants, it is in the possession of a more perfect organization.

From all which facts Mr. Carruthers thus argues:

The complete absence of intermediate forms, and the sudden and contemporaneous appearance of highly organized and widely separated groups, deprive the hypothesis of genetic evolution of any countenance from the plant-record of these ancient rocks. The whole evidence is against evolution, and there is none for it.[252]

Dicotyledons furnish evidence of especial value. On account of their higher organization, they are easily distinguished from both Monocotyledons and Gymnosperms; and they present features which clearly differentiate them amongst themselves. They did not make their entry till after a long interval--and their remains are therefore to be found in strata comparatively recent and better known to us than those of the older rocks. It is in the Chalk, the newest of the Secondary or Mesozoic formations, that they first exhibit themselves, and they do it in the same fas.h.i.+on as their predecessors.

When the Dicotyledons appear in the upper cretaceous beds, representatives of the three great groups [_Apetalae_, _Monopetalae_, _Polypetalae_] appear together in the same deposit. Moreover, these divisions are represented, not by generalized types, but by differentiated forms, which, during the intervening epochs, have not developed even into higher generic groups.

And, here again, there is no vestige of intermediate species, linking dicotyledonous plants with other types.

No trace of a plant belonging to this great division has yet been detected in any earlier stratum [than the upper chalk]. There is no evidence whatever for Haeckel's statement that the _Apetalae_ probably existed in the Tria.s.sic and Jura.s.sic periods.... It cannot be doubted that the conditions favourable to the preservation of Monocotyledons and Equisetums would have secured the preservation of some of the _Apetalae_, had they existed. This absence can be accounted for only on the supposition that they formed no part of the then existing vegetation. And in the deposits older than the Trias, or in any subsequent deposits, no intermediate form has been detected,--no Gymnosperm or Monocotyledon which exhibits in any point of its structure a modification towards the more highly organized Dicotyledon.

Nor, on the same authority, is this all.

It is equally important in its bearing on the hypothesis of genetic evolution that the generic groups above named have persisted from the first known appearance of Dicotyledons, throughout the whole of the intervening ages, and still hold their places unchanged among the existing forms of vegetation. The persistence of generic and specific types, and the certain knowledge we possess of the life of many existing species of Phanerogams and Cryptogams which have come down through the Glacial Epoch, have not been sufficiently considered in their bearing on the hypothesis.

We have already seen something of an example which ill.u.s.trates this point in a remarkable manner,--that of _Salix polaris_, the willow which has so obstinately preserved its specific ident.i.ty amid great stress of circ.u.mstances. It belongs to a very variable genus--one in which if anywhere evidence of genetic development might be looked for. Yet it is found that since a period prior to the great Ice Age, or Glacial epoch, it has remained absolutely unchanged. At such a rate, we cannot but ask, how long would Evolution take to get back to the generalized type-form, or common ancestor, of the genus _Salix_, and then to that of the Order _Salicineae_, which includes poplars as well as willows. "The Ordinal form, if it ever existed, must necessarily be much older than the period of the upper Cretaceous rocks, that is than the period to which the earliest known Dicotyledons belong."

And it is obvious that when we had got back to the parental stock of the willow tribe, we should still, as evolutionists, be separated by a gulf still vastly greater from the common ancestor of all Dicotyledons, of oaks, apple-trees, primroses, and daisies no less than of willows and poplars.

The significance of all these various facts is thus summed up:

The whole evidence supplied by fossil plants is, then, opposed to the hypothesis of genetic evolution, and especially the sudden and simultaneous appearance of the most highly organized plants at particular stages in the past history of the globe, and the entire absence amongst fossil plants of any forms intermediate between existing cla.s.ses or families. The facts of palaeontological botany are opposed to Evolution, but they testify to Development, to progression from lower to higher types. The cellular Algae preceded the Vascular Cryptogams and the Gymnosperms of the Newer Palaeozoic rocks, and these were speedily followed by Monocotyledons, and, at a much later period, by Dicotyledons. But the earliest representatives of these various sections of the vegetable kingdom were not generalized forms, but as highly organized as recent forms, and in many cases more highly organized: and the divisions were as clearly bounded in their essential characters, and as decidedly separated from each other as they are at the present day.

So much for the vegetable world. As for the animal, although the number and complexity of its divisions makes it less easy to present so complete a sketch in these moderate limits, the features of its history are very similar. As Sir J. W. Dawson recounts it:[253]

ANIMAL DEVELOPMENT.

+----------------------------------------------------+ Post Tertiary. Man and Modern Mammals. +----------------------------------------------------+ { Pliocene. { +----------------------------------------------------+ Tertiary. { Miocene. { +-------------------+--------------------------------+ { Eocene. Placental Mammals (Ungulates, { Unguiculates, Rodents, { Whales, Bats). +-------------------+--------------------------------+ { Chalk. { +-------------------+--------------------------------+ Secondary.{ Oolite. Birds. { +-------------------+--------------------------------+ { Trias. Marsupial Mammals. +-------------------+--------------------------------+ { Permian. Reptiles (various orders). { +-------------------+--------------------------------+ { Carboniferous. { +-------------------+--------------------------------+ { Devonian, or Millipeds, Insects, Spiders, { Old Red Sandstone. Scorpions, Fish, Batrachians, { etc. { +-------------------+--------------------------------+ Primary. { Silurian. { +-------------------+--------------------------------+ { Cambrian. Sh.e.l.l Fish, Sponges, Molluscs, { Crustaceans, Worms, etc. { +-------------------+--------------------------------+ { Huronian. } { +-------------------+--}----------------------------- { Laurentian. } Protozoa. +===================+================================+ AZOIC.

In the Cambrian age, we obtain a vast and varied accession of living things, which appear at once, as if by a sudden and simultaneous production of many kinds of animals. Here we find evidence that the sea swarmed with creatures near akin to those which still inhabit it, and nearly as varied.... Had we been able to drop our dredge into the Cambrian or Silurian ocean, we should have brought up representatives of all the leading types of invertebrate life that exist in the modern seas--different, it is true, in details of structure from those now existing, but constructed on the same principles, and filling the same places in nature.

In the latter half of the Palaeozoic we find a number of higher forms breaking upon us with the same apparent suddenness as in the case of the early Cambrian animals. Fishes appear, and soon abound in a great variety of species, representing types of no mean rank, but, singularly enough, belonging in many cases to groups now very rare; while the commoner tribes of modern fish do not appear. On the land, Batrachian Reptiles now abound, some of them very high in the sub-cla.s.s to which they belong. Scorpions, spiders, insects, and millipedes appear as well as land-snails: and this not in one locality only, but over the whole northern hemisphere.... Nor do they show any signs of an unformed or imperfect state.... The compound eyes and filmy wings of insects, the teeth, bones, and scales of batrachians and fishes; all are as perfectly finished, and many quite as complex and elegant, as the animals of the present day.

This wonderful Palaeozoic age was, however, but a temporary state of the earth. It pa.s.sed away, and was replaced by the Mesozoic, emphatically the age of Reptiles, when animals of that type attained to colossal magnitude, to variety of function and structure, to diversity of habitat in sea and on land, altogether unexampled in their degraded descendants of modern times.... Strangely enough, with these reptilian lords appeared a few small and lowly mammals, forerunners of the coming age.[254] Birds also made their appearance.

The Kainozoic, or Tertiary, is the age of Mammals and of Man. In it the great reptilian tyrants of the Mesozoic disappear, and are replaced on land and sea by mammals or beasts of the same orders with those now living, though differing as to genera and species. So greatly indeed did mammalian life abound in this period that in the middle part of the Tertiary most of the leading groups were represented by more numerous species than at present, while many types then existing

have now no representatives. At the close of this great and wonderful procession of living beings comes Man himself--the last and crowning triumph of creation the head, thus far, of life on the earth.

[Ill.u.s.tration: DIAGRAM ILl.u.s.tRATING THE PROGRESS OF ORGANIC DEVELOPMENT.

In the above Diagram the progress of Organic Development, as manifested in higher and higher types, is indicated by the increasing divergence of new forms from primitive simplicity of structure, represented by the medium line separating the vegetable and animal kingdoms.

The _Supposed line of continuous Evolution,_ indicates the gradual course which should be taken by Development, on Darwinian or Spencerian principles, by acc.u.mulation of minute differences in successive generations, as contrasted with the abrupt and simultaneous appearance of highly differentiated types, as spoken of by palaeontologists.

[_To face page 227._]]

It must be sufficient to quote one other remark:[255]

There is no direct evidence that in the course of geological time one species has been gradually or suddenly changed into another....

On the other hand, we constantly find species replaced by others entirely new, and this without any transition. The two cla.s.ses of facts are essentially different, though often confounded by evolutionists; and though it is possible to point out in the newer geological formations some genera and species allied to others which have preceded them, and to suppose that the later forms proceeded from the earlier, still, as the connecting links cannot be found, this is mere supposition, not scientific certainty.

Further, it proceeds on the principle of arbitrary choice of certain forms out of many, without any evidence of genetic connexion.

Having given a tabular view of Geological periods and Life-epochs, similar to those presented above, our author remarks:[256]

If in the table above we were to represent diagrammatically the development of animals and plants, this would appear not as a smooth and continuous stream, but as a series of great waves, each rising abruptly, and then descending and flowing on at a lower level along with the remains of those preceding it.

And here may be noticed an observation made amongst others by the Comte de Saporta[257] on the remarkable parallelism of Animal and Vegetable development. After a period in which these kingdoms were respectively represented by aquatic _Algae_ and _Protozoa_, land animals and land plants appear to have come in much at the same epoch; and afterwards dicotyledonous plants immediately preceded the advent of mammals.

Mr. Mivart is of like mind with the others we have heard. "The ma.s.s of palaeontological evidence," he writes,[258] "is indeed overwhelmingly against minute and gradual modification." He points out, with the _North British_ Reviewer so frequently quoted, that had the later forms of life descended from the earlier, through such a series of imperceptible gradations as is imagined, the probability would be that no two fossil specimens would be exactly alike, whereas in fact numbers are found of certain particular patterns, and none whatever between them, fossil animals and plants falling naturally into species, genera, families, and other categories just like those of the present day.

It is this total absence of graduated series, linking different forms together, that is the great and fundamental difficulty in the way of genetic evolution. Yet this seems very seldom to be realized, and it seems constantly to be a.s.sumed that in order to establish the genetic continuity of two creatures no more is required than to discover another standing more or less between them. Thus in the most famous of all instances, how often do we hear of "the missing link" between man and ape,--as though should a generalized form be disclosed, which might be considered a common ancestor, the question of man's simian origin would be finally settled. In the same way, as we have seen, the existence of birds with reptilian features, is taken by some as conclusive proof that birds and reptiles have descended from one stock.

But what is most imperatively wanted, is persistently wanting,--namely some evidence of a series in which one form pa.s.ses to another, as in a dissolving view. And yet, genetic evolutionists must suppose such series to have been the universal rule throughout the whole course of life on earth.

a.s.suredly [writes M. de Quatref.a.ges][259] is it not singularly unfortunate for the evolutionary theory that so many facts which tell against it should have been preserved in the sc.r.a.ps of Nature's great book which remain to us, and that invariably those which would have told in its favour were recorded in lost volumes and missing leaves?