A Chain of Jungle Life

I

I OFFER a living chain of ten links: the first, a tiny, delicate being, one hundred to the inch, deep in the jungle, with the strangest home in the world; my last, You, the present reader of these lines. Between, there befall certain things of which I attempt falteringly to write. To know and think them is very worth while; to have discovered them is sheer joy; but to write of them is impertinence, so exciting and unreal are they in reality, and so tame and humdrum are any combinations of our twenty-six letters.

Somewhere to-day a worm has given up existence, a mouse has been slain, a spider snatched from the web, a junglebird torn sleeping from its perch; else we should have no song of robin, no flash of reynard’s red, no humming flight of wasp, no grace of crouching ocelot. In tropical jungles, in northern home orchards, anywhere you will, unnumbered activities of bird and beast and insect require daily toll of life.

Now and then we actually witness one of these tragedies, — or successes, whichever point of view we take, — appearing to us as an exciting but isolated event. When once we grasp the idea of chains of life, each of these occurrences assumes a new meaning. Like everything else in the world, it is not isolated, but closely linked with other similar happenings. I have sometimes traced even closed chains, one of the shortest of which consisted of predacious flycatchers, which fed upon young lizards of a species which, when they grew up, climbed trees and devoured the nestling flycatchers!

One of the most wonderful houses ‘that Jack built,’ was this of Opalina’s — a long, swinging, exciting chain, including in its links a Protozoan, two stages of Amphibians, a Fish, two Birds, and (unless some intervening act of anti-evolution legislature bars the fact as immoral and illegal) three Mammals—myself, the Editor, and You.

As I do not want to make it into a mere imaginary animal story, however probable, I will begin, like Conrad, in the middle. I can cope, however lamely, with the entrance and participation of the earlier links, but am wholly out of my depth from the time when I mail my tale. The Akawai Indian who took it on its first lap toward the editor should by rights have a place in the chain, especially when I think how much better he might tell of the interrelationships of the various links than can I. Still, I know the shape of the owl’s wings when it dropped on the snake, but I do not know why the editor accepted this; I can imitate the death-scream of the frog when the fish seized it, but I have no clue as to the reason for Your entry into the chain by the purchase of this magazine, nor whether you perceive in my tale the huge bed of ignorance in which I have planted this scanty crop of facts. Nor do I know the future of this copy — whether it will go to the garret, to be ferreted out in future years by other links, as I used to ferret; or whether it will find its way to midAsia or the Malay States; or be found, as once I saw a copy, half-buried, like the pyramids, in Saharan sands, where it had slipped from the camel-load of some unknown traveler.

I left my Kartabo laboratory one morning, with my gun, headed for the old Dutch stelling. Happening to glance up, I saw a mote, lit with the oblique rays of the morning sun. The mote drifted about in circles, which became spirals; the mote became a dot, then a spot, then an oblong; and down the heavens from unknown heights, with the whole of British Guiana spread out beneath him from which to choose, swept a vulture into my very path. We had a quintette — a small flock of our own vultures — who came sifting down from the sky, day after day, to the feast of monkey bodies and wild peccaries which we spread for them. I knew all these by sight, from one peculiarity or another; for I was accustomed to watch them hour after hour, striving to learn something of that wonderful soaring, of which all my many hours of flying had taught me nothing.

This was a stranger, perhaps from the coast or the inland savannas; for to these birds great spaces are only matters of brief moments. I wanted a yellow-headed vulture, both for the painting of its marvelous head colors, and for the strange, intensely interesting, one-sided, down-at-the-heel syrinx, which, with the voice, had dissolved long ages ago, leaving only a whistling breath and an irregular complex of bones straggling over the windpipe.

Some day I shall dilate upon vultures as pets, being surpassed in cleanliness, affectionateness, and tameness only by baby bears, sloths, and certain monkeys. But to-day I wanted the newcomer as a specimen. I was surprised to see that he did not head for the regular vulture table, but slid along a slant of the east wind, banked around its side, spreading and curling upward his wing-fingertips, and finally resting against the front edge of the breeze. Down this he sank slowly, balancing with the grace of perfect mastery, and again swung round and settled suddenly down shore, beyond a web of mangrove roots. This took me by surprise, and I changed my route and pushed through the undergrowth of young palms. Before I came within sight, the bird heard me, rose with a whipping of great pinions, and swept around three fourths of a circle before I could catch enough of a glimpse to drop him. The impetus carried him on, and completed the circle, and when I came out on the Cuyuni shore, I saw him spread out on what must have been the exact spot from which he had risen.

I walked along a greenheart log, with little crabs scuttling off on each side; and, as I looked ahead at the vulture, I saw to my great surprise that it had more colors than any yellow-headed vulture should have, and its plumage was somehow very different. This excited me so that I promptly slipped off the log and joined the crabs in the mud. Paying more attention to my steps, I did not again look up until I reached the tuft of low reeds on which the bird lay. Now, at last, I understood why my bird had metamorphosed in death, and also why it had chosen to descend to this spot. Instead of one bird, there were two, and a reptile. Another tragedy had taken place a few hours earlier, before dawn, — a double death, — and the sight of these three creatures brought to mind at once the chain for which I am always on the lookout.

I picked up my chain by the middle, and began searching both ways for the missing links.

The vulture lay with magnificent wings outspread, partly covering a big spectacled owl, whose disheveled plumage was, in turn, wrapped about by several coils of a moderate-sized anaconda. Here was an excellent start in one direction for my chain, and at once I visualized myself and the snake, although alternate links, yet coupled in contradistinction to my editor and the vulture, the first two having entered the chain by means of death, whereas the vulture had simply joined in the pacifistic manner of its kind; and as my editor has dealt gently with me heretofore, I allowed myself to believe that his entrance might also be an innocuous one.

The head of the vulture was already losing some of its brilliant chrome and saffron, so I noted the condition of the surrounding sand and mud, and gathered together my spoils. I should have passed within a few feet of the owl and the snake and never have discovered them, so close were they in color to the dark reddish beach; yet the vulture, with its small eyes and minute nerves, had detected this tragedy when still perhaps a mile high in the air, or half a mile up-river. There could have been no odor, nor has the bird any adequate nostrils to detect it, had there been one. It was sheer keenness of vision. I looked at the bird’s claws, and their weakness showed the necessity of the eternal search for carrion, or recently killed creatures. Here in a half-minute, it had devoured an eye of the owl and both of those of the serpent. It is a curious thing, this predilection for eyes; give a monkey a fish, and the eyes are the first tidbits taken.

II

Through the vulture I come to the owl link — a splendid bird, clad in the colors of its time of hunting; a great soft dark shadow of a bird, with tiny body and long fluffy plumage of twilight buff and ebony night, lit by twin orange moons of eyes. The name, spectacled owl, is really more applicable to the downy nestling, which is like a white powder puff with two dark feathery spectacles around the eyes. Its name is one of those which I am fond of repeating rapidly — Pulsatrix perspicillata perspicillata. Etymologies do not grow in the jungle, and my memory is noted only for its consistent vagueness; but if the owl’s title does not mean The Eyebrowed One Who Strikes, it ought to, especially as the subspecific trinomial grants it two eyebrows.

I would give much to know just what the beginning of the combat was like. The middle I could reconstruct without question, and the end was only too apparent. By a most singular coincidence, a few years before and less than three miles away, I found the desiccated remains of another spectacled owl, mingled with the bones of a snake; only in that instance the fangs indicated a small fer-de-lance, the owl having succumbed to its venom. This time the owl had rashly attacked a serpent far too heavy for it to lift, or even, as it turned out, successfully to battle with. The mud had been churned up for a foot in all directions, and the bird’s plumage showed that it must have rolled over and over. The anaconda, having just fed, had come out of the water, and was probably stretched out on the sand and mud, as I have seen them, both by full sun and in the moonlight. These owls are birds rather of the creeks and river-banks than of the deep jungle, and among their food I have found shrimps, crabs, fish, and young birds. Once a few snake vertebræ showed that these reptiles are occasionally killed and devoured.

Whatever possessed the bird to strike its talons deep into the neck and back of this anaconda, none but the owl could say; but from then on the story was written by the combatants and their environment. The snake, like a flash, threw two coils around the bird, wings and all, and clamped these tight with a cross-vise of muscle. The tighter the coils compressed, the deeper the talons of the bird were driven in; but the damage was done with the first strike, and if owl and snake had parted at this moment, neither could have survived. It was a swift, terrible, and short fight. The snake could not use its teeth, and the bird had no time to bring its beak into play; and there in the night, with the lapping waves of the falling tide only two or three feet away, the two creatures of prey met and fought and died, in darkness and silence, locked fast together.

A few nights before, I had heard, on the opposite side of the bungalow, the deep, sonorous cry of the spectacled owl; within the week I had passed the line-and-crescent tracks of anacondas, one about the size of this snake and another much larger. And now Fate had linked their lives, or rather deaths, with me, using as her divining rod, the focusing of a sky-soaring vulture.

The owl had not fed that evening, although the bird was so well nourished that it could never have been driven to its foolhardy feat by stress of hunger. Hopeful of lengthening the chain, I rejoiced to see a suspicious swelling about the middle of the snake, which dissection resolved into a good-sized fish — itself carnivorous, locally called a basha. This was the first time I had known one of these fish to fall a victim to a land creature, except in the case of a big kingfisher who had caught two small ones. Like the owl and anaconda, bashas are nocturnal in their activities, and, according to their size, feed on small shrimps, big shrimps, and so on up to six-inch or eight-inch catfish. They are built on swift, torpedo-like stream lines, and clad in iridescent silver mail.

From what I have seen of the habits of anacondas, I should say that this one had left its hole, high up among the upper-beach roots, late in the night, and softly wound its way down into the rising tide. Here, after drinking, the snake sometimes pursues and catches small fish and frogs; but the usual method is to coil up beside a half-buried stick or log, and await the tide and the manna it brings. In the van of the waters comes a host of small fry, followed by their pursuers, or by larger vegetable feeders, and the serpent has but to choose.

In this mangrove lagoon, then, there must have been a swirl and a splash, a passive holding fast by the snake for a while, until the right opportunity offered, and then a swift throw of coils. There must, then, be no mistake as to orientation of the fish. It would be a fatal error to attempt the tail first, with scales on end and serried spines to pierce the thickest tissues. It is beyond my knowledge how one of these fish can be swallowed, even head first, without serious laceration. But here was optical proof of its possibility — a newswallowed basha, so recently caught that he appeared as in life, with even the delicate turquoise pigment beneath his scales, acting on his silvery armor as quicksilver under glass: the tooth-marks of the snake were still clearly visible on the scales. I registered another link, going steadily down the classes of vertebrates, mammal, bird, reptile, and fish, and still my magic boxes were unexhausted.

Excitedly I cut open the fish. An organism more unlike that of the snake would be hard to imagine. There I had followed an elongated stomach, and had left unexplored many feet of alimentary canal. Here, the fish had his heart literally in his mouth, while his other livers and lights were only a short distance behind, followed by a great expanse of tail, to wag him at its will, and drive him through the water with the speed of twin-propellers. His eyes are wonderful for night-hunting — large, wide, and bent in the middle, so that he can see both above and on each side. But all this wide-angled vision availed nothing against the lidless, motionless watch of the ambushed anaconda. Searching the crevices of the rocks and logs for timorous small fry, the basha had sculled too close, and the jaws which closed upon him were backed by too much muscle, and too perfect a throttling machine, to allow of the least chance of escape. It was a big basha compared with the moderate-sized snake, but the fierce eyes had judged well, as the evidence before me proved.

Still my chain held true, and in the stomach of the basha I found what I wanted: another link, and more than I could have hoped for — a representative of the fifth and last class of vertebrate animals living on the earth—an Amphibian, an enormous frog. This, too, had been a swift-forged link, so recent that digestion had affected only the head of the creature. I drew it out, set it upon its great squat legs, and there was a grandmother frog almost as in life — a Pok-poke, as the Indians call it, or, — as a herpetologist would prefer, — Leptodactylus caliginosus, the Smoky Jungle Frog.

She lived in the jungle just behind, where she and a sister of hers had their curious nests of foam, which they guarded from danger, while the tadpoles grew and squirmed within its sudsy mesh, as if there were no water in the world. I had watched one of the two, perhaps this very one, for hours, and saw her dart angrily after little fish which came too near. Then, this night, the high, full-moon tides had swept over the barrier back of the mangrove roots, and set the tadpoles free, and the mother frogs were at liberty to go where they pleased.

From my cot in the bungalow to the south, I had heard, in the early part of the night, the death-scream of a frog, and it must have been at that moment that somehow the basha had caught the great amphibian. This frog is one of the fiercest of its class, and captures mice, reptiles, and small fish without trouble. It is even cannibalistic on very slight provocation, and two of equal size will sometimes endeavor to swallow one another in the most appallingly matter-of-fact manner.

They represent the opposite extreme in temperament from the pleasantly philosophical giant toads. In outward appearance, in the dim light of dusk, the two groups are not unlike; but the moment they are taken in the hand, all doubt ceases. After one dive for freedom, the toad resigns himself to fate, only venting his spleen in much puffing out of his sides; while the frog either fights until exhausted, or pretends death until opportunity offers for a last mad dash.

In this case the frog must have leaped into deep water beyond the usual barrier, and, while swimming, have been attacked by the equally voracious fish. In addition to the regular croak of this species, it has a most unexpected and un-amphibian yell or scream, given only when it thinks itself at the last extremity. It is most unnerving when the frog, held firmly by the hind legs, suddenly puts its whole sold into an ear-splitting peent! peent! peent ! peent !

Many a time they are probably saved from death by this cry, which startles like a sudden blow; but to-night no utterance in the world coidd have

saved it; its assailant was dumb and all but deaf to aerial sounds. Its cries were smothered in the water, as the fish dived and nuzzled it about the roots, as bashas do with their food — and it became another link in the chain.

Like a miser with one empty coffer, or a gambler with an unfilled royal flush, I went eagerly at the frog, with forceps and scalpel. But beyond a meagre residuum of eggs, there was nothing but shrunken organs in its body. The rashness of its venture into river water was perhaps prompted by hunger after its long maternal fast, while it watched over its egg-filled nest of foam.

Hopeful to the last, I scrape some mucus from its food canal, place it in a drop of water under my microscope, and—discover Opalina, my last link, which, in the course of its most astonishing life-history, gives me still another.

III

To the naked eye there is nothing visible — the water seems clear; but when I enlarge it fifty diameters, I lift the veil on another world, and there swim into view a dozen minute lives — little oval beings covered with curving lines, giving the appearance of wandering finger-prints. In some lights these are iridescent, and they then well deserve the name of Opalina. As for their personality, they are oval and rather flat; it would take one hundred of them to stretch an inch; they have no mouth, and they are covered with a fur of flagella, with which they whip themselves through the water. Indeed, the whole of their little selves consists of a multitude of nuclei, sometimes as many as two hundred, exactly alike — facial expression, profile, torso, limbs, pose, all are summed up in rounded nuclei, partly obscured by a mist of vibrating flagella.

As for their gait, they move along in colored waves, steadily and gently, not keeping an absolutely straight course, and making rather a good deal of leeway, as any rounded, keelless craft, surrounded by its own paddlewheels, must expect to do.

I have placed Opalina under very strange and unpleasant conditions, in thus subjecting it to the inhospitable qualities of a drop of clear water. Even as I watch, it begins to slow down, and the flagella move less rapidly and evenly. It prefers an environment far different, the one where I discovered it living, happy and contented —in the stomach and intestines of a frog, where its iridescence was lost, or rather had never existed in the absolute darkness; where its delicate hairs often must have been unmercifully crushed and bent in the ever-moving tube; and where air and sky, trees and sun, sound and color were forever unknown, in their place only bits of half-digested ants and beetles, thousand-legs and worms, rolled and tumbled along in the dense gastric stream of acid pepsin; a strange choice of home for one of our fellow living beings on the earth.

After an Opalina has flagellated itself about and fed for a time, in its strange, almost crystalline way, on the juices of its host’s food, its body begins to contract, and narrows across the centre, until it looks somewhat like a map of the New World. Finally, its isthmus thread breaks, and two Opalinas swim placidly off, both identical, except that each has half the number of nuclei. We cannot wonder that there is no backward glance, or wave of cilia, or even memory of their other body; for they are themselves, or rather it is they, or it is each: our whole vocabulary, our entire stock of pronouns, our grammar, our very conception of individuality, is shattered by the life of Opalina.

Each daughter-cell or self-twin, or whatever we choose to conceive it, divides in turn. Finally there comes a day (or rather some Einstein period of space-time, for there are no days in a frog’s stomach) when Opalina’s fraction has reached a stage with only two nuclei. When tins has creased and stretched, and finally broken, like two bits of drawn-out molasses candy, we have the last divisional possibility. The time for the great adventure has arrived, with decks cleared for action — or, as a protozoblogist would put it, with the flagellate’s protoplasm uninucleate, approximating encystment.

The encysting process is but slightly understood, but the tiny one-two-hundredth-of-its-former-self Opalina curls up, its paddle-wheels run down, it forms a shell, and rolls into the current which it has withstood for a protozoan’s lifetime. Out into the world drifts the minute ball of latent life, a plaything of the cosmos, permitted neither to see, nor hear, nor eat, nor to move of its own volition. It hopes (only it cannot even desire) to find itself in water; it must fall or be washed into a pool with tadpoles, one of which must come along at the right moment and swallow it with the débris upon which it rests. The possibility of this elaborate concatenation of events has everything against it, and yet it must occur, or death will result. No wonder that the population of Opalinas does not overstock its limited and retired environment.

Supposing that all happens as it should, and that the only chance in a hundred thousand comes to pass, the encysted being knows, or is affected in some mysterious way by entrance into the body of the tadpole. The cyst is dissolved and the infant Opalina begins to feed and to develop new nuclei. Like the queen ant, after she has been walled forever into her chamber, the life of the little ‘ one-cell ‘ would seem to be extremely sedentary and humdrum, in fact monotonous, until its turn came to fractionize itself, and again severally to go into the outside world, multiplied and by installments. But as the queen ant had her one superlative day of sunlight, heavenly flight, and a mate, so Opalina, while she is still wholly herself, has a little adventure all her own.

Let us strive to visualize her environment , as it would appear to her if she could find time and ability within her single cell, to do more than feed and bisect herself. Once free from her horny cyst, she stretches her drop of a body, sets all her paddle-hairs in motion, and swims slowly off. If we suppose that she has been swallowed by a tadpole an inch long, her living quarters are astonishingly spacious or, rather, elongated. Passing from end to end, she would find a living tube two feet in length—a dizzy path to traverse, as it is curled in a tight, many-whorled spiral: the stairway, the domicile, the universe at present, for Opalina. She is compelled to be a vegetarian, for nothing but masses of decayed leaf-tissue, black mud, and alga? come down the stairway. For many days there is only the sound of water gurgling past the tadpole’s gills,or glimpses of st icks and leaves, and the occasional flash of a small fish through the thin skin periscope of its body.

Then the tadpole’s mumbling, even of half-rotted leaves, conies to an end, and both it and its guest begin to fast. Down the whorls comes less and less of vegetable detritus, and Opalina must feel like the crew of a submarine w hen the food-supply runs short. At the same time, something very strange happens, the experience of w hich eludes our utmost imagination. Poe wrote a memorable tale of a prison cell which day by day grew smaller, and Opalina goes through much the same adventure. If she frequently traverses her tube, she finds it growing shorter and shorter. As it contracts, the spiral untwists and straightens out, while all the time the rations are cut off. A dark curtain of pigment is draw n across the epidermal periscope, and, as books of dire adventure say, ‘the horror of darkness is added to the terrible mental uncertainly.’ The whole movement of the organism changes: there is no longer the rush and sw ish of water, and the even, undulatory motion alters to a series of spasmodic jerks — quite the opposite of ordinary’ transition from water to land. Instead of water rushing through the gills of her host, Opalina might now hear strange musical sounds, loud and low, the singing of insects, the soughing of swamp-palms.

Opalina, about this time, should be feeling very low in her mind, if she had one, from lack of food, and the uncertainty of explanation why, the larger her host grew, the smaller, more confined became her quarters. The tension is relieved at last by a new influx of provender, but not inert mould or disintegrated leaves. Down the short, straight tube appears a live millipede, kicking as only a millipede can, with its thousand heels. Deserting for a moment Opalina’s point of view, my scientific conscience insists on asserting itself to the effect that no millipede with which I am acquainted has even half a thousand legs. But not to quibble over details, even a few hundred kicking legs must make quite a commotion in Opalina’s home, before the pepsin puts a quietus on the unwilling invader.

From now on there is no lack of food, for at each sudden jerk of the whole amphibian there comes down some animal or other. The vegetarian tadpole, with its enormously lengthened digestive apparatus, has crawled out on land, fasting while the miracle is being wrought with its plumbing; and when the readjustment is made to more easily assimilated animal food, and it has become a frog, it forgets all about leaves and algæ, and leaps after and captures almost any living creature which crosses its path, and which is small enough to be engulfed.

With the refurnishing of her apartment and the sudden and complete change of diet, the exigencies of life are past for Opalina. She has now but to move blindly about, bathed in a stream of nutriment, and, from time to time, nonchalantly to cut herself in twain. Only one other possibility awaits — that which occurred in the case of our Opalina. There comes a time when the sudden leap is not followed by an inrush of food, but by another leap and still another, and finally a headlong dive, a splash and a rush of water, which, were protozoans given to reincarnated memory, might recall times long past. Suddenly comes a violent spasm, then a terrible struggle, ending in a strange quiet: Opalina has become a link.

All motion is at an end, and, instead of food, comes compression; closer and closer shut the walls, and soon they break down and a new fluid pours in. Opalina’s cyst had dissolved readily in the tadpole’s stomach, while her own body was able to withstand what all the food of tadpole and frog could not. Hut now, if I had not wanted the painting of a vulture’s head, little Opalina, together with the body of her life-long host, would have corroded and melted, and in the dark depths of the tropical waters her multitude of paddle-hairs, her more or fewer nuclei, all would have dissolved and been reabsorbed, to furnish their iota of energy to the swift silvery fish.

This flimsy little skyscraper castle of Jack’s, built of isolated bricks of facts, gives a hint of the wonderland of correlation. Facts are necessary; but even a pack-rat can assemble a gallon of beans in a single night. To link facts together, to see them forming into a concrete whole; to make A fit into Arch, and Arch into Architecture — that is one of the greatest joys of life which, of all the links in my chain, only the Editor, You, and I — the mammals — can know.