Edge of the Jungle Part 6

I thought of the first handful of sand thrown out for the base of Cheops, of the first brick placed in position for the Great Wall, of a fresh-cut trunk, rough-hewn and squared for a log-cabin on Manhattan; of the first shovelful of earth flung out of the line of the Panama Ca.n.a.l. Yet none seemed worthy of comparison with even what little I knew of the significance of this ant's labor, for this was earnest of what would make trivial the engineering skill of Egyptians, of Chinese patience, of munic.i.p.al pride and continental schism.

Imagine sawing off a barn-door at the top of a giant sequoia, growing at the bottom of the Grand Canon, and then, with five or six children clinging to it, descending the tree, and carrying it up the canon walls against a subway rush of rude people, who elbowed and pushed blindly against you. This is what hundreds of leaf-cutting ants accomplish daily, when cutting leaves from a tall bush, at the foot of the bank near the laboratory.

There are three dominant labor-unions in the jungle, all social insects, two of them ants, never interfering with each other's field of action, and all supremely ill.u.s.trative of conditions resulting from absolute equality, free-and-equalness, communalism, socialism carried to the (forgive me!) anth power. The Army Ants are carnivorous, predatory, militant nomads; the Termites are vegetarian scavengers, sedentary, negative and provincial; the Attas, or leaf-cutting ants, are vegetarians, active and dominant, and in many ways the most interesting of all.

The casual observer becomes aware of them through their raids upon gardens; and indeed the Attas are a very serious menace to agriculture in many parts of the tropics, where their nests, although underground, may be as large as a house and contain millions of individuals. While their choice among wild plants is exceedingly varied, it seems that there are certain things they will not touch; but when any human-reared flower, vegetable, shrub, vine, or tree is planted, the Attas rejoice, and straightway desert the native vegetation to fall upon the newcomers. Their whims and irregular feeding habits make it difficult to guard against them. They will work all round a garden for weeks, perhaps pa.s.s through it _en route_ to some tree that they are defoliating, and then suddenly, one night, every Atta in the world seems possessed with a desire to work havoc, and at daylight the next morning, the garden looks like winter stubble--a vast expanse of stems and twigs, without a single remaining leaf. Volumes have been written, and a whole chemist's shop of deadly concoctions devised, for combating these ants, and still they go steadily on, gathering leaves which, as we shall see, they do not even use for food.

Although essentially a tropical family, Attas have pushed as far north as New Jersey, where they make a tiny nest, a few inches across, and bring to it bits of pine needles.

In a jungle Baedeker, we should double-star these insects, and paragraph them as "_Atta_, named by Fabricius in 1804; the Kartabo species, _cephalotes_; Leaf-cutting or Cushie or Parasol Ants; very abundant.

_Atta_, a subgenus of _Atta_, which is a genus of _Attii_, which is a tribe of _Myrmicinae_, which is a subfamily of _Formicidae_," etc.

With a feeling of slightly greater intimacy, of mental possession, we set out, armed with a name of one hundred and seventeen years'

standing, and find a big Atta worker carving away at a bit of leaf, exactly as his ancestors had done for probably one hundred and seventeen thousand years.

We gently lift him from his labor, and a drop of chloroform banishes from his ganglia all memory of the hundred thousand years of pruning.

Under the lens his strange personality becomes manifest, and we wonder whether the old Danish zoologist had in mind the slender toe-tips which support him, or in a chuckling mood made him a namesake of C.

Quintius Atta. A close-up shows a very comic little being, encased in a p.r.i.c.kly, chestnut-colored armor, which should make him fearless in a den of a hundred anteaters. The front view of his head is a bit mephistophelian, for it is drawn upward into two h.o.r.n.y spines; but the side view recalls a little girl with her hair brushed very tightly up and back from her face.

The connection between Atta and the world about him is furnished by this same head: two huge, flail-shaped antennae arching up like aerial, detached eyebrows--vehicles, through their golden pile, of senses which foil our most delicate tests. Outside of these are two little shoe-b.u.t.ton eyes; and we are not certain whether they reflect to the head ganglion two or three hundred bits of leaf, or one large mosaic leaf. Below all is swung the pair of great scythes, so edged and hung that they can function as jaws, rip-saws, scissors, forceps, and clamps. The thorax, like the head of a t.i.tanothere, bears three pairs of horns--a great irregular expanse of tumbled, rock-like skin and thorn, a foundation for three pairs of long legs, and sheltering somewhere in its heart a thread of ant-life; finally, two little pedicels lead to a rounded abdomen, smaller than the head. This Third-of-an-inch is a worker Atta to the physical eye; and if we catch another, or ten, or ten million, we find that some are small, others much larger, but that all are cast in the same mold, all indistinguishable except, perhaps, to the shoe-b.u.t.ton eyes.

When a worker has traveled along the Atta trails, and has followed the temporary mob-instinct and climbed bush or tree, the same irresistible force drives him out upon a leaf. Here, apparently, instinct slightly loosens its hold, and he seems to become individual for a moment, to look about, and to decide upon a suitable edge or corner of green leaf. But even in this he probably has no choice. At any rate, he secures a good hold and sinks his jaws into the tissue.

Standing firmly on the leaf, he measures his distance by cutting across a segment of a circle, with one of his hind feet as a center.

This gives a very true curve, and provides a leaf-load of suitable size. He does not scissor his way across, but bit by bit sinks the tip of one jaw, hook-like, into the surface, and brings the other up to it, slicing through the tissue with surprising ease. He stands upon the leaf, and I always expect to see him cut himself and his load free, Irishman-wise. But one or two of his feet have invariably secured a grip on the plant, sufficient to hold him safely. Even if one or two of his fellows are at work farther down the leaf, he has power enough in his slight grip to suspend all until they have finished and clambered up over him with their loads.

Holding his bit of leaf edge-wise, he bends his head down as far as possible, and secures a strong purchase along the very rim. Then, as he raises his head, the leaf rises with it, suspended high over his back, out of the way. Down the stem or tree-trunk he trudges, head first, fighting with gravitation, until he reaches the ground. After a few feet, or, measured by his stature, several hundred yards, his infallible instinct guides him around pebble boulders, mossy orchards, and gra.s.s jungles to a specially prepared path.

Thus in words, in sentences, we may describe the cutting of a single leaf; but only in the imagination can we visualize the cell-like or crystal-like duplication of this throughout all the great forests of Guiana and of South America. As I write, a million jaws snip through their stint; as you read, ten million Attas begin on new bits of leaf.

And all in silence and in dim light, legions pa.s.sing along the little jungle roads, unending lines of trembling banners, a political parade of ultra socialism, a procession of chlorophyll floats ill.u.s.trating unreasoning unmorality, a fairy replica of "Birnam Forest come to Dunsinane."

In their leaf-cutting, Attas have mastered ma.s.s, but not form. I have never seen one cut off a piece too heavy to carry, but many a hard-sliced bit has had to be deserted because of the configuration of the upper edge. On almost any trail, an ant can be found with a two-inch stem of gra.s.s, attempting to pa.s.s under a twig an inch overhead. After five or ten minutes of pushing, backing, and pulling, he may accidentally march off to one side, or reach up and climb over; but usually he drops his burden. His little works have been wound up, and set at the mark "home"; and though he has now dropped the prize for which he walked a dozen ant-miles, yet any idea of cutting another stem, or of picking up a slice of leaf from those lying along the trail, never occurs to him. He sets off homeward, and if any emotion of sorrow, regret, disappointment, or secret relief troubles his ganglia, no trace of it appears in antennae, carriage, or speed. I can very readily conceive of his trudging st.u.r.dily all the way back to the nest, entering it, and going to the place where he would have dumped his load, having fulfilled his duty in the spirit at least. Then, if there comes a click in his internal time-clock, he may set out upon another quest--more cabined, cribbed, and confined than any member of a Cook's tourist party.

I once watched an ant with a piece of leaf which had a regular shepherd's crook at the top, and if his adventures of fifty feet could have been caught on a moving-picture film, Charlie Chaplin would have had an arthropod rival. It hooked on stems and pulled its bearer off his feet, it careened and ensnared the leaves of other ants, at one place mixing up with half a dozen. A big thistledown became tangled in it, and well-nigh blew away with leaf and all; hardly a foot of his path was smooth-going. But he persisted, and I watched him reach the nest, after two hours of tugging and falling and interference with traffic.

Occasionally an ant will slip in crossing a twiggy creva.s.se, and his leaf become tightly wedged. After sprawling on his back and vainly clawing at the air for a while, he gets up, brushes off his antennae, and sets to work. For fifteen minutes I have watched an Atta in this predicament, stodgily endeavoring to lift his leaf while standing on it at the same time. The equation of push equaling pull is fourth dimensional to the Attas.

With all this terrible expenditure of energy, the activities of these ants are functional within very narrow limits. The blazing sun causes them to drop their burdens and flee for home; a heavy wind frustrates them, for they cannot reef. When a gale arises and sweeps an exposed portion of the trail, their only resource is to cut away all sail and heave it overboard. A sudden downpour reduces a thousand banners and waving, bright-colored petals to debris, to be trodden under foot.

Sometimes, after a ten-minute storm, the trails will be carpeted with thousands of bits of green mosaic, which the outgoing hordes will trample in their search for more leaves. On a dark night little seems to be done; but at dawn and dusk, and in the moonlight or clear starlight, the greatest activity is manifest.

Attas are such unpalatable creatures that they are singularly free from dangers. There is a tacit armistice between them and the other labor-unions. The army ants occasionally make use of their trails when they are deserted; but when the two great races of ants meet, each antennaes the aura of the other, and turns respectfully aside. When termites wish to traverse an Atta trail, they burrow beneath it, or build a covered causeway across, through which they pa.s.s and repa.s.s at will, and over which the Attas trudge, uncaring and unconscious of its significance.

Only creatures with the toughest of digestions would dare to include these p.r.i.c.kly, strong-jawed, meatless insects in a bill of fare. Now and then I have found an ani, or black cuckoo, with a few in its stomach: but an ani can swallow a stinging-haired caterpillar and enjoy it. The most consistent feeder upon Attas is the giant marine toad. Two hundred Attas in a night is not an uncommon meal, the exact number being verifiable by a count of the undigested remains of heads and abdomens. _Bufo marinus_ is the gardener's best friend in this tropic land, and besides, he is a gentleman and a philosopher, if ever an amphibian was one.

While the cutting of living foliage is the chief aim in life of these ants, yet they take advantage of the flotsam and jetsam along the sh.o.r.e, and each low tide finds a column from some nearby nest salvaging flowerets, leaves, and even tiny berries. A sudden wash of tide lifts a hundred ants with their burdens and then sets them down again, when they start off as if nothing had happened.

The paths or trails of the Attas represent very remarkable feats of engineering, and wind about through jungle and glade for surprising distances. I once traced a very old and wide trail for well over two hundred yards. Taking little Third-of-an-inch for a type (although he would rank as a rather large Atta), and comparing him with a six-foot man, we reckon this trail, ant-ratio, as a full twenty-five miles.

Belt records a leaf-cutter's trail half a mile long, which would mean that every ant that went out, cut his tiny bit of leaf, and returned, would traverse a distance of a hundred and sixteen miles. This was an extreme; but our Atta may take it for granted, speaking antly, that once on the home trail, he has, at the least, four or five miles ahead of him.

The Atta roads are clean swept, as straight as possible, and very conspicuous in the jungle. The chief high-roads leading from very large nests are a good foot across, and the white sand of their beds is visible a long distance away. I once knew a family of opossums living in a stump in the center of a dense thicket. When they left at evening, they always climbed along as far as an Atta trail, dropped down to it, and followed it for twenty or thirty yards. During the rains I have occasionally found tracks of agoutis and deer in these roads. So it would be very possible for the Attas to lay the foundation for an animal trail, and this, _a la_ calf-path, for the street of a future city.

The part that scent plays in the trails is evidenced if we scatter an inch or two of fresh sand across the road. A ma.s.s of ants banks against the strange obstruction on both sides, on the one hand a solid phalanx of waving green banners, and on the other a mob of empty-jawed workers with wildly waving antennae. Scouts from both sides slowly wander forward, and finally reach one another and pa.s.s across. But not for ten minutes does anything like regular traffic begin again.

When carrying a large piece of leaf, and traveling at a fair rate of speed, the ants average about a foot in ten seconds, although many go the same distance in five. I tested the speed of an Atta, and then I saw that its leaf seemed to have a peculiar-shaped bug upon it, and picked it up with its bearer. Finding the blemish to be only a bit of fungus, I replaced it. Half an hour later I was seated by a trail far away, when suddenly my ant with the blemished spot appeared. It was unmistakable, for I had noticed that the spot was exactly that of the Egyptian symbol of life. I paced the trail, and found that seventy yards away it joined the spot where I had first seen my friend. So, with occasional spurts, he had done two hundred and ten feet in thirty minutes, and this in spite of the fact that he had picked up a supercargo.

Two parts of hydrogen and one of oxygen, under the proper stimulus, invariably result in water; two and two, considered calmly and without pa.s.sion, combine into four; the workings of instinct, especially in social insects, is so mechanical that its results can almost be demonstrated in formula; and yet here was my Atta leaf-carrier burdened with a minim. The worker Attas vary greatly in size, as a glance at a populous trail will show. They have been christened _macrergates, desmergates_ and _micrergates_; or we may call the largest Maxims, the average middle cla.s.s Mediums, and the tiny chaps Minims, and all have more or less separate functions in the ecology of the colony. The Minims are replicas in miniature of the big chaps, except that their armor is pale cinnamon rather than chestnut.

Although they can bite ferociously, they are too small to cut through leaves, and they have very definite duties in the nest; yet they are found with every leaf-cutting gang, hastening along with their larger brethren, but never doing anything, that I could detect, at their journey's end. I have a suspicion that the little Minims, who are very numerous, function as light cavalry; for in case of danger they are as eager at attack as the great soldiers, and the leaf-cutters, absorbed in their arduous labor, would benefit greatly from the immunity ensured by a flying corps of their little bulldog comrades.

I can readily imagine that these nestling Minims become weary and foot-sore (like bank-clerks guarding a reservoir), and if instinct allows such abominable individuality, they must often wish themselves back at the nest, for every mile of a Medium is three miles to them.

Here is where our mechanical formula breaks down; for, often, as many as one in every five leaves that pa.s.s bears aloft a Minim or two, clinging desperately to the waving leaf and getting a free ride at the expense of the already overburdened Medium. Ten is the extreme number seen, but six to eight Minims collected on a single leaf is not uncommon. Several times I have seen one of these little banner-riders shift deftly from leaf to leaf, when a swifter carrier pa.s.sed by, as a circus bareback rider changes steeds at full gallop.

Once I saw enacted above ground, and in the light of day, something which may have had its roots in an _anlage_ of divine discontent. If I were describing the episode half a century ago, I should ent.i.tle it, "The Battle of the Giants, or Emotion Enthroned." A quadruple line of leaf-carriers was disappearing down a hole in front of the laboratory, b.u.mped and pushed by an out-pouring, empty-jawed ma.s.s of workers. As I watched them, I became aware of an area of great excitement beyond the hole. Getting down as nearly as possible to ant height, I witnessed a terrible struggle. Two giants--of the largest soldier Maxim caste--were locked in each other's jaws, and to my horror, I saw that each had lost his abdomen. The antennae and the abdomen petiole are the only vulnerable portions of an Atta, and long after he has lost these apparently dispensable portions of his anatomy, he is able to walk, fight, and continue an active but erratic life. These mighty-jawed fellows seem never to come to the surface unless danger threatens; and my mind went down into the black, musty depths, where it is the duty of these soldiers to walk about and wait for trouble. What could have raised the ire of such stolid neuters against one another? Was it sheer lack of something to do? or was there a cell or two of the winged caste lying fallow within their bodies, which, stirring at last, inspired a will to battle, a pa.s.sing echo of romance, of the activities of the male Atta?

Their unnatural combat had stirred scores of smaller workers to the highest pitch of excitement. Now and then, out of the melee, a Medium would emerge, with a tiny Minim in his jaws. One of these carried his still living burden many feet away, along an unused trail, and dropped it. I examined the small ant, and found that it had lost an antenna, and its body was crushed. When the ball of fighters cleared, twelve small ants were seen clinging to the legs and heads of the mutilated giants, and now and then these would loosen their hold on each other, turn, and crush one of their small tormenters. Several times I saw a Medium rush up and tear a small ant away, apparently quite insane with excitement.

Occasionally the least exhausted giant would stagger to his four and a half remaining legs, hoist his a.s.sailant, together with a ma.s.s of the midgets, high in air, and stagger for a few steps, before falling beneath the onrush of new attackers. It made me wish to help the great insect, who, for aught I knew, was doomed because he was different--because he had dared to be an individual.

I left them struggling there, and half an hour later, when I returned, the episode was just coming to a climax. My Atta hero was exerting his last strength, flinging off the pile that a.s.saulted him, fighting all the easier because of the loss of his heavy body. He lurched forward, dragging the second giant, now dead, not toward the deserted trail or the world of jungle around him, but headlong into the lines of stupid leaf-carriers, scattering green leaves and flower-petals in all directions. Only when dozens of ants threw themselves upon him, many of them biting each other in their wild confusion, did he rear up for the last time, and, with the whole mob, rolled down into the yawning mouth of the Atta nesting-hole, disappearing from view, and carrying with him all those hurrying up the steep sides. It was a great battle.

I was breathing fast with sympathy, and whatever his cause, I was on his side.

The next day both giants were lying on the old, disused trail; the revolt against absolute democracy was over; ten thousand ants pa.s.sed to and fro without a dissenting thought, or any thought, and the Spirit of the Attas was content.

VIII

THE ATTAS AT HOME

Clambering through white, pasty mud which stuck to our boots by the pound, peering through bitter cold mist which seemed but a thinner skim of mud, drenched by flurries of icy drops shaken from the atmosphere by a pa.s.sing moan and a crash, breathing air heavy with a sweet, horrible, penetrating odor--such was the world as it existed for an hour one night, while I and the Commandant of _Douaumont_ wandered about completely lost, on the top of his own fort. We finally stumbled on the little grated opening through which the lookout peered unceasingly over the landscape of mud. The mist lifted and we rediscovered the cave-like entrance, watched for a moment the ominous golden dumb-bells rising from the premier ligne, sc.r.a.ped our boots on a German helmet and went down again into the strangest sanctuary in the world.

This was the vision which flashed through my mind as I began vigil at an enormous nest of Attas--the leaf-cutting ants of the British Guiana jungle. In front of me was a glade, about thirty feet across, devoid of green growth, and filled with a great irregular expanse of earth and mud. Relative to the height of the Attas, my six feet must seem a good half mile, and from this height I looked down and saw again the same inconceivably sticky clay of France. There were the rain-washed gullies, the half-roofed entrances to the vast underground fortresses, clean-swept, perfect roads, as efficient as the arteries of Verdun, flapping dead leaves like the omnipresent, worn-out scare-crows of camouflage, and over in one corner, to complete the simile, were a dozen sh.e.l.l-holes, the homes of voracious ant-lions, which, for pa.s.sing insects, were unexploded mines, set at hair trigger.

My Atta city was only two hundred feet away from the laboratory, in fairly high jungle, within sound of the dinner triangle, and of the lapping waves on the Mazaruni sh.o.r.e. To sit near by and concentrate solely upon the doings of these ant people, was as easy as watching a single circus ring of performing elephants, while two more rings, a maze of trapezes, a race track and side-shows were in full swing. The jungle around me teemed with interesting happenings and distracting sights and sounds. The very last time I visited the nest and became absorbed in a line of incoming ants, I heard the shrill squeaking of an angry hummingbird overhead. I looked up, and there, ten feet above, was a furry tamandua anteater slowly climbing a straight purpleheart trunk, while around and around his head buzzed and swore the little fury--a pinch of cinnamon feathers, ablaze with rage. The curved claws of the unheeding anteater fitted around the trunk and the strong prehensile tail flattened against the bark, so that the creature seemed to put forth no more exertion than if walking along a fallen log. Now and then it stopped and daintily picked at a bit of termite nest.

With such side-shows it was sometimes difficult to concentrate on the Attas. Yet they offered problems for years of study. The glade was a little world in itself, with visitors and tenants, comedy and tragedy, sounds and silences. It was an ant-made glade, with all new growths either choked by upflung, earthen hillocks, or leaves bitten off as soon as they appeared. The casual visitors were the most conspicuous, an occasional trogon swooping across--a glowing, feathered comet of emerald, azurite and gold; or, slowly drifting in and out among the vines and coming to rest with waving wings, a yellow and red spotted Ithomiid,--or was it a Heliconiid or a Danaiid?--with such bewildering models and marvelous mimics it was impossible to tell without capture and close examination. Giant, purple tarantula-hawks hummed past, scanning the leaves for their prey.

Another cla.s.s of glade haunters were those who came strictly on business,--plasterers and sculptors, who found wet clay ready to their needs. Great golden and rufous bees blundered down and gouged out bucketsful of mud; while slender-bodied, dainty, ebony wasps, after much fastidious picking of place, would detach a tiny bit of the whitest clay, place it in their snuff-box holder, clean their feet and antennae, run their rapier in and out and delicately take to wing.

Little black trigonid bees had their special quarry, a small deep valley in the midst of a waste of interlacing Bad Lands, on the side of a precipitous b.u.t.te. Here they picked and shoveled to their hearts'

content, plastering their thighs until their wings would hardly lift them. They braced their feet, whirred, lifted unevenly, and sank back with a jar. Then turning, they bit off a piece of ballast, and heaving it over the precipice, swung off on an even keel.

Close examination of some of the craters and volcanic-like cones revealed many species of ants, beetles and roaches searching for bits of food--the scavengers of this small world. But the most interesting were the actual parasites, flies of many colors and sizes, humming past like little planes and zeppelins over this hidden city, ready to drop a bomb in the form of an egg deposited on the refuse heaps or on the ants themselves. The explosion might come slowly, but it would be none the less deadly. Once I detected a hint of the complexity of the glade life--beautiful metallic green flies walking swiftly about on long legs, searching nervously, whose eggs would be deposited near those of other flies, their larvae to feed upon the others--parasites upon parasites.

As I had resolutely put the doings of the treetops away from my consciousness, so now I forgot visitors and parasites, and armed myself for the excavation of this buried metropolis. I rubbed vaseline on my high boots, and about the tops bound a band of teased-out absorbent cotton. My pick and shovel I treated likewise, and thus I was comparatively insulated. Without precautions no living being could withstand the slow, implacable attack of disturbed Attas.

At present I walked unmolested across the glade. The millions beneath my feet were as unconscious of my presence as they were of the breeze in the palm fronds overhead.