'The Atlantosaurus,' said I, pointing affectionately with a wave of my left hand to all that was immortal of that extinct reptile, 'is estimated to have had a total length of one hundred feet, and was probably the very biggest lizard that ever lived, even in Western America, where his earthly remains were first disinhumed by an enthusiastic explorer.'
'Yes, yes,' my friend answered abstractedly. 'Of course, of course; things were all so very big in those days, you know, my dear fellow.'
'Excuse me,' I replied with polite incredulity; 'I really don't know to what particular period of time the phrase "in those days" may be supposed precisely to refer.'
My friend shuffled inside his coat a little uneasily. (I will admit that I was taking a mean advantage of him. The professorial lecture in private life, especially when followed by a strict examination, is quite undeniably a most intolerable nuisance.) 'Well,' he said, in a crusty voice, after a moment's hesitation, 'I mean, you know, in geological times ... well, there, my dear fellow, things used all to be so _very_ big in those days, usedn't they?'
I took compassion upon him and let him off easily. 'You've had enough of the museum,' I said with magnanimous self-denial. 'The Atlantosaurus has broken the camel's back. Let's go and have a quiet cigarette in the park outside.'
But if you suppose, reader, that I am going to carry my forbearance so far as to let you, too, off the remainder of that geological disquisition, you are certainly very much mistaken. A discourse which would be quite unpardonable in social intercourse may be freely admitted in the privacy of print; because, you see, while you can't easily tell a man that his conversation bores you (though some people just avoid doing so by an infinitesimal fraction), you can shut up a book whenever you like, without the very faintest or remotest risk of hurting the author's delicate susceptibilities.
The subject of my discourse naturally divides itself, like the conventional sermon, into two heads--the precise date of 'geological times,' and the exact bigness of the animals that lived in them. And I may as well begin by announcing my general conclusion at the very outset; first, that 'those days' never existed at all; and, secondly, that the animals which now inhabit this particular planet are, on the whole, about as big, taken in the lump, as any previous contemporary fauna that ever lived at any one time together upon its changeful surface. I know that to announce this sad conclusion is to break down one more universal and cherished belief; everybody considers that 'geological animals' were ever so much bigger than their modern representatives; but the interests of truth should always be paramount, and, if the trade of an iconoclast is a somewhat cruel one, it is at least a necessary function in a world so ludicrously overstocked with popular delusions as this erring planet.
What, then, is the ordinary idea of 'geological time' in the minds of people like my good friend who refused to discuss with me the exact antiquity of the Atlantosaurian? They think of it all as immediate and contemporaneous, a vast panorama of innumerable ages being all crammed for them on to a single mental sheet, in which the dodo and the moa hob-an'-nob amicably with the pterodactyl and the ammonite; in which the tertiary megatherium goes cheek by jowl with the secondary deinosaurs and the primary trilobites; in which the huge herbivores of the Paris Basin are supposed to have browsed beneath the gigantic club-mosses of the Carboniferous period, and to have been successfully hunted by the great marine lizards and flying dragons of the Jurassic Epoch. Such a picture is really just as absurd, or, to speak more correctly, a thousand times absurder, than if one were to speak of those grand old times when Homer and Virgil smoked their pipes together in the Mermaid Tavern, while Shakespeare and Moliere, crowned with summer roses, sipped their Falernian at their ease beneath the whispering palmwoods of the Nevsky Prospect, and discussed the details of the play they were to produce to-morrow in the crowded Colosseum, on the occasion of Napoleon's reception at Memphis by his victorious brother emperors, Ramses and Sardanapalus. This is not, as the inexperienced reader may at first sight imagine, a literal transcript from one of the glowing descriptions that crowd the beautiful pages of Ouida; it is a faint attempt to parallel in the brief moment of historical time the glaring anachronisms perpetually committed as regards the vast lapse of geological chronology even by well-informed and intelligent people.
We must remember, then, that in dealing with geological time we are dealing with a positively awe-inspiring and unimaginable series of aeons, each of which occupied its own enormous and incalculable epoch, and each of which saw the dawn, the rise, the culmination, and the downfall of innumerable types of plant and animal. On the cosmic clock, by whose pendulum alone we can faintly measure the dim ages behind us, the brief lapse of historical time, from the earliest of Egyptian dynasties to the events narrated in this evening's _Pall Mall_, is less than a second, less than a unit, less than the smallest item by which we can possibly guide our blind calculations. To a geologist the temples of Karnak and the New Law Courts would be absolutely contemporaneous; he has no means by which he could discriminate in date between a scarabaeus of Thothmes, a denarius of Antonine, and a bronze farthing of her Most Gracious Majesty Queen Victoria. Competent authorities have shown good grounds for believing that the Glacial Epoch ended about 80,000 years ago; and everything that has happened since the Glacial Epoch is, from the geological point of view, described as 'recent.' A shell embedded in a clay cliff sixty or seventy thousand years ago, while short and swarthy Mongoloids still dwelt undisturbed in Britain, ages before the irruption of the 'Ancient Britons' of our inadequate school-books, is, in the eyes of geologists generally, still regarded as purely modern.
But behind that indivisible moment of recent time, that eighty thousand years which coincides in part with the fraction of a single swing of the cosmical pendulum, there lie hours, and days, and weeks, and months, and years, and centuries, and ages of an infinite, an illimitable, an inconceivable past, whose vast divisions unfold themselves slowly, one beyond the other, to our aching vision in the half-deciphered pages of the geological record. Before the Glacial Epoch there comes the Pliocene, immeasurably longer than the whole expanse of recent time; and before that again the still longer Miocene, and then the Eocene, immeasurably longer than all the others put together. These three make up in their sum the Tertiary period, which entire period can hardly have occupied more time in its passage than a single division of the Secondary, such as the Cretaceous, or the Oolite, or the Triassic; and the Secondary period, once more, though itself of positively appalling duration, seems but a patch (to use the expressive modernism) upon the unthinkable and unrealisable vastness of the endless successive Primary aeons. So that in the end we can only say, like Michael Scott's mystic head, 'Time was, Time is, Time will be.' The time we know affords us no measure at all for even the nearest and briefest epochs of the time we know not; and the time we know not seems to demand still vaster and more inexpressible figures as we pry back curiously, with wondering eyes, into its dimmest and earliest recesses.
These efforts to realise the unrealisable make one's head swim; let us hark back once more from cosmical time to the puny bigness of our earthly animals, living or extinct.
If we look at the whole of our existing fauna, marine and terrestrial, we shall soon see that we could bring together at the present moment a very goodly collection of extant monsters, most parlous monsters, too, each about as fairly big in its own kind as almost anything that has ever preceded it. Every age has its own _specialite_ in the way of bigness; in one epoch it is the lizards that take suddenly to developing overgrown creatures, the monarchs of creation in their little day; in another, it is the fishes that blossom out unexpectedly into Titanic proportions; in a third, it is the sloths or the proboscideans that wax fat and kick with gigantic members; in a fourth, it may be the birds or the men that are destined to evolve with future ages into veritable rocs or purely realistic Gargantuas or Brobdingnagians. The present period is most undoubtedly the period of the cetaceans; and the future geologist who goes hunting for dry bones among the ooze of the Atlantic, now known to us only by the scanty dredgings of our 'Alerts' and 'Challengers,' but then upheaved into snow-clad Alps or vine-covered Apennines, will doubtless stand aghast at the huge skeletons of our whales and our razorbacks, and will mutter to himself in awe-struck astonishment, in the exact words of my friend at South Kensington, 'Things used all to be so very big in those days, usedn't they?'
Now, the fact as to the comparative size of our own cetaceans and of 'geological' animals is just this. The Atlantosaurus of the Western American Jurassic beds, a great erect lizard, is the very largest creature ever known to have inhabited this sublunary sphere. His entire length is supposed to have reached about a hundred feet (for no complete skeleton has ever been discovered), while in stature he appears to have stood some thirty feet high, or over. In any case, he was undoubtedly a very big animal indeed, for his thigh-bone alone measures eight feet, or two feet taller than that glory of contemporary civilisation, a British Grenadier. This, of course, implies a very decent total of height and size; but our own sperm whale frequently attains a good length of seventy feet, while the rorquals often run up to eighty, ninety, and even a hundred feet. We are thus fairly entitled to say that we have at least one species of animal now living which, occasionally at any rate, equals in size the very biggest and most colossal form known inferentially to geological science. Indeed when we consider the extraordinary compactness and rotundity of the modern cetaceans, as compared with the tall limbs and straggling skeleton of the huge Jurassic deinosaurs, I am inclined to believe that the tonnage of a decent modern rorqual must positively exceed that of the gigantic Atlantosaurus, the great lizard of the west, _in propria persona_. I doubt, in short, whether even the solid thigh-bone of the deinosaur could ever have supported the prodigious weight of a full-grown family razor-back whale. The mental picture of these unwieldy monsters hopping casually about, like Alice's Gryphon in Tenniel's famous sketch, or like that still more parlous brute, the chortling Jabberwock, must be left to the vivid imagination of the courteous reader, who may fill in the details for himself as well as he is able.
If we turn from the particular comparison of selected specimens (always an unfair method of judging) to the general aspect of our contemporary fauna, I venture confidently to claim for our own existing human period as fine a collection of big animals as any other ever exhibited on this planet by any one single rival epoch. Of course, if you are going to lump all the extinct monsters and horrors into one imaginary unified fauna, regardless of anachronisms, I have nothing more to say to you; I will candidly admit that there were more great men in all previous generations put together, from Homer to Dickens, from Agamemnon to Wellington, than there are now existing in this last quarter of our really very respectable nineteenth century. But if you compare honestly age with age, one at a time, I fearlessly maintain that, so far from there being any falling off in the average bigness of things generally in these latter days, there are more big things now living than there ever were in any one single epoch, even of much longer duration than the 'recent' period.
I suppose we may fairly say, from the evidence before us, that there have been two Augustan Ages of big animals in the history of our earth--the Jurassic period, which was the zenith of the reptilian type, and the Pliocene, which was the zenith of the colossal terrestrial tertiary mammals. I say on purpose, 'from the evidence before us,' because, as I shall go on to explain hereafter, I do not myself believe that any one age has much surpassed another in the general size of its fauna, since the Permian Epoch at least; and where we do not get geological evidence of the existence of big animals in any particular deposit, we may take it for granted, I think, that that deposit was laid down under conditions unfavourable to the preservation of the remains of large species. For example, the sediment now being accumulated at the bottom of the Caspian cannot possibly contain the bones of any creature much larger than the Caspian seal, because there are no big species there swimming; and yet that fact does not negative the existence in other places of whales, elephants, giraffes, buffaloes, and hippopotami. Nevertheless, we can only go upon the facts before us; and if we compare our existing fauna with the fauna of Jurassic and Pliocene times, we shall at any rate be putting it to the test of the severest competition that lies within our power under the actual circumstances.
In the Jurassic age there were undoubtedly a great many very big reptiles. 'A monstrous eft was of old the lord and master of earth: For him did his high sun flame and his river billowing ran: And he felt himself in his pride to be nature's crowning race.' There was the ichthyosaurus, a fish-like marine lizard, familiar to us all from a thousand reconstructions, with his long thin body, his strong flippers, his stumpy neck, and his huge pair of staring goggle eyes. The ichthyosaurus was certainly a most unpleasant creature to meet alone in a narrow strait on a dark night; but if it comes to actual measurement, the very biggest ichthyosaurian skeleton ever unearthed does not exceed twenty-five feet from snout to tail. Now, this is an extremely decent size for a reptile, as reptiles go; for the crocodile and alligator, the two biggest existing lizards, seldom attain an extreme length of sixteen feet. But there are other reptiles now living that easily beat the ichthyosaurus, such, for example, as the larger pythons or rock-snakes, which not infrequently reach to thirty feet, and measure round the waist as much as a London alderman of the noblest proportions. Of course, other Jurassic saurians easily beat this simple record. Our British Megalosaurus only extended twenty-five feet in length, and carried weight not exceeding three tons; but, his rival Ceteosaurus stood ten feet high, and measured fifty feet from the tip of his snout to the end of his tail; while the dimensions of Titanosaurus may be briefly described as sixty feet by thirty, and those of Atlantosaurus as one hundred by thirty-two. Viewed as reptiles, we have certainly nothing at all to come up to these; but our cetaceans, as a group, show an assemblage of species which could very favourably compete with the whole lot of Jurassic saurians at any cattle show. Indeed, if it came to tonnage, I believe a good blubbery right-whale could easily give points to any deinosaur that ever moved upon oolitic continents.
The great mammals of the Pliocene age, again, such as the deinotherium and the mastodon, were also, in their way, very big things in livestock; but they scarcely exceeded the modern elephant, and by no means came near the modern whales. A few colossal ruminants of the same period could have held their own well against our existing giraffes, elks, and buffaloes; but, taking the group as a group, I don't think there is any reason to believe that it beat in general aspect the living fauna of this present age.
For few people ever really remember how very many big animals we still possess. We have the Indian and the African elephant, the hippopotamus, the various rhinoceroses, the walrus, the giraffe, the elk, the bison, the musk ox, the dromedary, and the camel. Big marine animals are generally in all ages bigger than their biggest terrestrial rivals, and most people lump all our big existing cetaceans under the common and ridiculous title of whales, which makes this vast and varied assortment of gigantic species seem all reducible to a common form. As a matter of fact, however, there are several dozen colossal marine animals now sporting and spouting in all oceans, as distinct from one another as the camel is from the ox, or the elephant from the hippopotamus. Our New Zealand Berardius easily beats the ichthyosaurus; our sperm whale is more than a match for any Jurassic European deinosaur; our rorqual, one hundred feet long, just equals the dimensions of the gigantic American Atlantosaurus himself. Besides these exceptional monsters, our bottleheads reach to forty feet, our California whales to forty-four, our hump-backs to fifty, and our razor-backs to sixty or seventy. True fish generally fall far short of these enormous dimensions, but some of the larger sharks attain almost equal size with the biggest cetaceans. The common blue shark, with his twenty-five feet of solid rapacity, would have proved a tough antagonist, I venture to believe, for the best bred enaliosaurian that ever munched a lias ammonite. I would back our modern carcharodon, who grows to forty feet, against any plesiosaurus that ever swam the Jurassic sea. As for rhinodon, a gigantic shark of the Indian Ocean, he has been actually measured to a length of fifty feet, and is stated often to attain seventy. I will stake my reputation upon it that he would have cleared the secondary seas of their great saurians in less than a century. When we come to add to these enormous marine and terrestrial creatures such other examples as the great snakes, the gigantic cuttle-fish, the grampuses, and manatees, and sea-lions, and sunfish, I am quite prepared fearlessly to challenge any other age that ever existed to enter the lists against our own for colossal forms of animal life.
Again, it is a point worth noting that a great many of the very big animals which people have in their minds when they talk vaguely about everything having been so very much bigger 'in those days' have become extinct within a very late period, and are often, from the geological point of view, quite recent.
For example, there is our friend the mammoth. I suppose no animal is more frequently present to the mind of the non-geological speaker, when he talks indefinitely about the great extinct monsters, than the familiar figure of that huge-tusked, hairy northern elephant. Yet the mammoth, chronologically speaking, is but a thing of yesterday. He was hunted here in England by men whose descendants are probably still living--at least so Professor Boyd Dawkins solemnly assures us; while in Siberia his frozen body, flesh and all, is found so very fresh that the wolves devour it, without raising any unnecessary question as to its fitness for lupine food. The Glacial Epoch is the yesterday of geological time, and it was the Glacial Epoch that finally killed off the last mammoth. Then, again, there is his neighbour, the mastodon. That big tertiary proboscidean did not live quite long enough, it is true, to be hunted by the cavemen of the Pleistocene age, but he survived at any rate as long as the Pliocene--our day before yesterday--and he often fell very likely before the fire-split flint weapons of the Abbe Bourgeois' Miocene men. The period that separates him from our own day is as nothing compared with the vast and immeasurable interval that separates him from the huge marine saurians of the Jurassic world. To compare the relative lapses of time with human chronology, the mastodon stands to our own fauna as Beau Brummel stands to the modern masher, while the saurians stand to it as the Egyptian and Assyrian warriors stand to Lord Wolseley and the followers of the Mahdi.
Once more, take the gigantic moa of New Zealand, that enormous bird who was to the ostrich as the giraffe is to the antelope; a monstrous emu, as far surpassing the ostriches of to-day as the ostriches surpass all the other fowls of the air. Yet the moa, though now extinct, is in the strictest sense quite modern, a contemporary very likely of Queen Elizabeth or Queen Anne, exterminated by the Maoris only a very little time before the first white settlements in the great southern archipelago. It is even doubtful whether the moa did not live down to the days of the earliest colonists, for remains of Maori encampments are still discovered, with the ashes of the fireplace even now unscattered, and the close-gnawed bones of the gigantic bird lying in the very spot where the natives left them after their destructive feasts. So, too, with the big sharks. Our modern carcharodon, who runs (as I have before noted) to forty feet in length, is a very respectable monster indeed, as times go; and his huge snapping teeth, which measure nearly two inches long by one and a half broad, would disdain to make two bites of the able-bodied British seaman. But the naturalists of the 'Challenger' expedition dredged up in numbers from the ooze of the Pacific similar teeth, five inches long by four wide, so that the sharks to which they originally belonged must, by parity of reasoning, have measured nearly a hundred feet in length. This, no doubt, beats our biggest existing shark, the rhinodon, by some thirty feet. Still, the ooze of the Pacific is a quite recent or almost modern deposit, which is even now being accumulated on the sea bottom, and there would be really nothing astonishing in the discovery that some representatives of these colossal carcharodons are to this day swimming about at their lordly leisure among the coral reefs of the South Sea Islands. That very cautious naturalist, Dr. Guenther, of the British Museum, contents himself indeed by merely saying: 'As we have no record of living individuals of that bulk having been observed, the gigantic species to which these teeth belonged must probably have become extinct within a comparatively recent period.'
If these things are so, the question naturally suggests itself: Why should certain types of animals have attained their greatest size at certain different epochs, and been replaced at others by equally big animals of wholly unlike sorts? The answer, I believe, is simply this: Because there is not room and food in the world at any one time for more than a certain relatively small number of gigantic species. Each great group of animals has had successively its rise, its zenith, its decadence, and its dotage; each at the period of its highest development has produced a considerable number of colossal forms; each has been supplanted in due time by higher groups of totally different structure, which have killed off their predecessors, not indeed by actual stress of battle, but by irresistible competition for food and prey. The great saurians were thus succeeded by the great mammals, just as the great mammals are themselves in turn being ousted, from the land at least, by the human species.
Let us look briefly at the succession of big animals in the world, so far as we can follow it from the mutilated and fragmentary record of the geological remains.
The very earliest existing fossils would lead us to believe what is otherwise quite probable, that life on our planet began with very small forms--that it passed at first through a baby stage. The animals of the Cambrian period are almost all small mollusks, star-fishes, sponges, and other simple, primitive types of life. There were as yet no vertebrates of any sort, not even fishes, far less amphibians, reptiles, birds, or mammals. The veritable giants of the Cambrian world were the crustaceans, and especially the trilobites, which, nevertheless, hardly exceeded in size a good big modern lobster. The biggest trilobite is some two feet long; and though we cannot by any means say that this was really the largest form of animal life then existing, owing to the extremely broken nature of the geological record, we have at least no evidence that anything bigger as yet moved upon the face of the waters. The trilobites, which were a sort of triple-tailed crabs (to speak very popularly), began in the Cambrian Epoch, attained their culminating point in the Silurian, waned in the Devonian, and died out utterly in the Carboniferous seas.
It is in the second great epoch, the Silurian, that the cuttle-fish tribe, still fairly represented by the nautilus, the argonaut, the squid, and the octopus, first began to make their appearance upon this or any other stage. The cuttle-fishes are among the most developed of invertebrate animals; they are rapid swimmers; they have large and powerful eyes; and they can easily enfold their prey (_teste_ Victor Hugo) in their long and slimy sucker-clad arms. With these natural advantages to back them up, it is not surprising that the cuttle family rapidly made their mark in the world. They were by far the most advanced thinkers and actors of their own age, and they rose almost at once to be the dominant creatures of the primaeval ocean in which they swam. There were as yet no saurians or whales to dispute the dominion with these rapacious cephalopods, and so the cuttle family had things for the time all their own way. Before the end of the Silurian Epoch, according to that accurate census-taker, M. Barrande, they had blossomed forth into no less than 1,622 distinct species. For a single family to develop so enormous a variety of separate forms, all presumably derived from a single common ancestor, argues, of course, an immense success in life; and it also argues a vast lapse of time during which the different species were gradually demarcated from one another.
Some of the ammonites, which belonged to this cuttle-fish group, soon attained a very considerable size; but a shell known as the orthoceras (I wish my subject didn't compel me to use such _very_ long words, but I am not personally answerable, thank heaven, for the vagaries of modern scientific nomenclature) grew to a bigger size than that of any other fossil mollusk, sometimes measuring as much as six feet in total length. At what date the gigantic cuttles of the present day first began to make their appearance it would be hard to say, for their shell-less bodies are so soft that they could leave hardly anything behind in a fossil state; but the largest known cuttle, measured by Mr. Gabriel, of Newfoundland, was eighty feet in length, including the long arms.
These cuttles are the only invertebrates at all in the running so far as colossal size is concerned, and it will be observed that here the largest modern specimen immeasurably beats the largest fossil form of the same type. I do not say that there were not fossil forms quite as big as the gigantic calamaries of our own time--on the contrary, I believe there were; but if we go by the record alone we must confess that, in the matter of invertebrates at least, the balance of size is all in favour of our own period.
The vertebrates first make their appearance, in the shape of fishes, towards the close of the Silurian period, the second of the great geological epochs. The earliest fish appear to have been small, elongated, eel-like creatures, closely resembling the lampreys in structure; but they rapidly developed in size and variety, and soon became the ruling race in the waters of the ocean, where they maintained their supremacy till the rise of the great secondary saurians. Even then, in spite of the severe competition thus introduced, and still later, in spite of the struggle for life against the huge modern cetaceans (the true monarchs of the recent seas), the sharks continued to hold their own as producers of gigantic forms; and at the present day their largest types probably rank second only to the whales in the whole range of animated nature. There seems no reason to doubt that modern fish, as a whole, quite equal in size the piscine fauna of any previous geological age.
It is somewhat different with the next great vertebrate group, the amphibians, represented in our own world only by the frogs, the toads, the newts, and the axolotls. Here we must certainly with shame confess that the amphibians of old greatly surpassed their degenerate descendants in our modern waters. The Japanese salamander, by far the biggest among our existing newts, never exceeds a yard in length from snout to tail; whereas some of the labyrinthodonts (forgive me once more) of the Carboniferous Epoch must have reached at least seven or eight feet from stem to stern. But the reason of this falling off is not far to seek. When the adventurous newts and frogs of that remote period first dropped their gills and hopped about inquiringly on the dry land, under the shadow of the ancient tree-ferns and club-mosses, they were the only terrestrial vertebrates then existing, and they had the field (or, rather, the forest) all to themselves. For a while, therefore, like all dominant races for the time being, they blossomed forth at their ease into relatively gigantic forms. Frogs as big as donkeys, and efts as long as crocodiles, luxuriated to their hearts' content in the marshy lowlands, and lorded it freely over the small creatures which they found in undisturbed possession of the Carboniferous isles. But as ages passed away, and new improvements were slowly invented and patented by survival of the fittest in the offices of nature, their own more advanced and developed descendants, the reptiles and mammals, got the upper hand with them, and soon lived them down in the struggle for life, so that this essentially intermediate form is now almost entirely restricted to its one adapted seat, the pools and ditches that dry up in summer.
The reptiles, again, are a class in which the biggest modern forms are simply nowhere beside the gigantic extinct species. First appearing on the earth at the very close of the vast primary periods--in the Permian age--they attained in secondary times the most colossal proportions, and have certainly never since been exceeded in size by any later forms of life in whatever direction. But one must remember that during the heyday of the great saurians, there were as yet no birds and no mammals. The place now filled in the ocean by the whales and grampuses, as well as the place now filled in the great continents by the elephants, the rhinoceroses, the hippopotami, and the other big quadrupeds, was then filled exclusively by huge reptiles, of the sort rendered familiar to us all by the restored effigies on the little island in the Crystal Palace grounds. Every dog has his day, and the reptiles had _their_ day in the secondary period. The forms into which they developed were certainly every whit as large as any ever seen on the surface of this planet, but not, as I have already shown, appreciably larger than those of the biggest cetaceans known to science in our own time.
During the very period, however, when enaliosaurians and pterodactyls were playing such pranks before high heaven as might have made contemporary angels weep, if they took any notice of saurian morality, a small race of unobserved little prowlers was growing up in the dense shades of the neighbouring forests which was destined at last to oust the huge reptiles from their empire over earth, and to become in the fulness of time the exclusively dominant type of the whole planet. In the trias we get the first remains of mammalian life in the shape of tiny rat-like animals, marsupial in type, and closely related to the banded ant-eaters of New South Wales at the present day. Throughout the long lapse of the secondary ages, across the lias, the oolite, the wealden, and the chalk, we find the mammalian race slowly developing into opossums and kangaroos, such as still inhabit the isolated and antiquated continent of Australia. Gathering strength all the time for the coming contest, increasing constantly in size of brain and keenness of intelligence, the true mammals were able at last, towards the close of the secondary ages, to enter the lists boldly against the gigantic saurians. With the dawn of the tertiary period, the reign of the reptiles begins to wane, and the reign of the mammals to set in at last in real earnest. In place of the ichthyosaurs we get the huge cetaceans; in place of the deinosaurs we get the mammoth and the mastodon; in place of the dominant reptile groups we get the first precursors of man himself.
The history of the great birds has been somewhat more singular. Unlike the other main vertebrate classes, the birds (as if on purpose to contradict the proverb) seem never yet to have had their day. Unfortunately for them, or at least for their chance of producing colossal species, their evolution went on side by side, apparently, with that of the still more intelligent and more powerful mammals; so that, wherever the mammalian type had once firmly established itself, the birds were compelled to limit their aspirations to a very modest and humble standard. Terrestrial mammals, however, cannot cross the sea; so in isolated regions, such as New Zealand and Madagascar, the birds had things all their own way. In New Zealand, there are no indigenous quadrupeds at all; and there the huge moa attained to dimensions almost equalling those of the giraffe. In Madagascar, the mammalian life was small and of low grade, so the gigantic aepyornis became the very biggest of all known birds. At the same time, these big species acquired their immense size at the cost of the distinctive birdlike habit of flight. A flying moa is almost an impossible conception; even the ostriches compete practically with the zebras and antelopes rather than with the eagles, the condors, or the albatrosses. In like manner, when a pigeon found its way to Mauritius, it developed into the practically wingless dodo; while in the northern penguins, on their icy perches, the fore limbs have been gradually modified into swimming organs, exactly analogous to the flippers of the seal.
Are the great animals now passing away and leaving no representatives of their greatness to future ages? On land at least that is very probable. Man, diminutive man, who, if he walked on all fours, would be no bigger than a silly sheep, and who only partially disguises his native smallness by his acquired habit of walking erect on what ought to be his hind legs--man has upset the whole balanced economy of nature, and is everywhere expelling and exterminating before him the great herbivores, his predecessors. He needs for his corn and his bananas the fruitful plains which were once laid down in prairie or scrubwood. Hence it seems not unlikely that the elephant, the hippopotamus, the rhinoceros, and the buffalo must go. But we are still a long way off from that final consummation, even on dry land; while as for the water, it appears highly probable that there are as good fish still in the sea as ever came out of it. Whether man himself, now become the sole dominant animal of our poor old planet, will ever develop into Titanic proportions, seems far more problematical. The race is now no longer to the swift, nor the battle to the strong. Brain counts for more than muscle, and mind has gained the final victory over mere matter. Goliath of Gath has shrunk into insignificance before the Gatling gun; as in the fairy tales of old, it is cunning little Jack with his clever devices who wins the day against the heavy, clumsy, muddle-headed giants. Nowadays it is our 'Minotaurs' and 'Warriors' that are the real leviathans and behemoths of the great deep; our Krupps and Armstrongs are the fire-breathing krakens of the latter-day seas. Instead of developing individually into huge proportions, the human race tends rather to aggregate into vast empires, which compete with one another by means of huge armaments, and invent mitrailleuses and torpedos of incredible ferocity for their mutual destruction. The dragons of the prime that tare each other in their slime have yielded place to eighty-ton guns and armour-plated turret-ships. Those are the genuine lineal representatives on our modern seas of the secondary saurians. Let us hope that some coming geologist of the dim future, finding the fossil remains of the sunken 'Captain,' or the plated scales of the 'Comte de Grasse,' firmly embedded in the upheaved ooze of the existing Atlantic, may shake his head in solemn deprecation at the horrid sight, and thank heaven that such hideous carnivorous creatures no longer exist in his own day.
[The end]
Grant Allen's essay: Big Animals