Chapter 9
Only creatures with the toughest of digestions would dare to include these prickly, 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 shore, 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, _à 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 mass 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 antennæ. Scouts from both sides slowly wander forward, and finally reach one another and pass 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 passion, 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 class 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 pass 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 passed 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 entitle 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, bumped and pushed by an out-pouring, empty-jawed mass 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 antennæ 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 passing 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 mêlée, 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 assailant, together with a mass 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 assaulted 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 passed 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 passing 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, scraped 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 shell-holes, the homes of voracious ant-lions, which, for passing 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 shore. 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 class 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 antennæ, 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 butte. 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 larvæ 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.
At the first deep shovel thrust, a slow-moving flood of reddish-brown began to pour forth from the crumbled earth--the outposts of the Atta Maxims moving upward to the attack. For a few seconds only workers of various sizes appeared, then an enormous head heaved upward and there came into the light of day the first Atta soldier. He was twice as large as a large worker and heavy in proportion. Instead of being drawn up into two spines, the top of his head was rounded, bald and shiny, and only at the back were the two spines visible, shifted downward. The front of the head was thickly clothed with golden hair, which hung down bang-like over a round, glistening, single, median eye. One by one, and then shoulder to shoulder, these Cyclopean Maxims lumbered forth to battle, and soon my boots were covered in spite of the grease, all sinking their mandibles deep into the leather.
When I unpacked these boots this year I found the heads and jaws of two Attas still firmly attached, relics of some forgotten foray of the preceding year. This mechanical, vise-like grip, wholly independent of life or death, is utilized by the Guiana Indians. In place of stitching up extensive wounds, a number of these giant Atta Maxims are collected, and their jaws applied to the edges of the skin, which are drawn together. The ants take hold, their bodies are snipped off, and the row of jaws remains until the wound is healed.
Over and around the out-pouring soldiers, the tiny workers ran and bit and chewed away at whatever they could reach. Dozens of ants made their way up to the cotton, but found the utmost difficulty in clambering over the loose fluff. Now and then, however, a needle-like nip at the back of my neck, showed that some pioneer of these shock troops had broken through, when I was thankful that Attas could only bite and not sting as well. At such a time as this, the greatest difference is apparent between these and the Eciton army ants. The Eciton soldier with his long, curved scimitars and his swift, nervous movements, was to one of these great insects as a fighting d'Artagnan would be to an armored tank. The results were much the same however,--perfect efficiency.
I now dug swiftly and crashed with pick down through three feet of soil. The great entrance arteries of the nest branched and bifurcated, separated and anastomosed, while here and there were chambers varying in size from a cocoanut to a football. These were filled with what looked like soft grayish sponge covered with whitish mold, and these somber affairs were the _raison d'être_ for all the leaf-cutting, the trails, the struggles through jungles, the constant battling against wind and rain and sun.
But the labors of the Attas are only renewed when a worker disappears down a hole with his hard-earned bit of leaf. He drops it and goes on his way. We do not know what this way is, but my guess is that he turns around and goes after another leaf. Whatever the nests of Attas possess, they are without recreation rooms. These sluggard-instructors do not know enough to take a vacation; their faces are fashioned for biting, but not for laughing or yawning. I once dabbed fifteen Mediums with a touch of white paint as they approached the nest, and within five minutes thirteen of them had emerged and started on the back track again.
The leaf is taken in charge by another Medium, hosts of whom are everywhere. Once after a spadeful, I placed my eye as close as possible to a small heap of green leaves, and around one oblong bit were five Mediums, each with a considerable amount of chewed and mumbled tissue in front of him. This is the only time I have ever succeeded in finding these ants actually at this work. The leaves are chewed thoroughly and built up into the sponge gardens, being used neither for thatch nor for food, but as fertilizer. And not for any strange subterranean berry or kernel or fruit, but for a fungus or mushroom. The spores sprout and proliferate rapidly, the gray mycelia covering the garden, and at the end of each thread is a little knobbed body filled with liquid. This forms the sole food of the ants in the nest, but a drop of honey placed by a busy trail will draw a circle of workers at any time--both Mediums and Minims, who surround it and drink their fill.
When the fungus garden is in full growth, the nest labors of the Minims begin, and until the knobbed bodies are actually ripe, they never cease to weed and to prune, thus killing off the multitude of other fungi and foreign organisms, and by pruning they keep their particular fungus growing, and prevent it from fructifying. The fungus of the Attas is a particular species with the resonant, Dunsanyesque name of _Rozites gongylophora_. It is quite unknown outside of the nests of these ants, and is as artificial as a banana.
Only in Calcutta bazaars at night, and in underground streets of Pekin, have I seen stranger beings than I unearthed in my Atta nest. Now and then there rolled out of a shovelful of earth, an unbelievably big and rotund Cicada larva--which in the course of time, whether in one or in seventeen years, would emerge as the great marbled winged _Cicada gigas_, spreading five inches from tip to tip. Small tarantulas, with beautiful wine-colored cephalothorax, made their home deep in the nest, guarded, perhaps, by their dense covering of hair; slender scorpions sidled out from the ruins. They were bare, with vulnerable joints, but they had the advantage of a pair of hands, and long, mobile arms, which could quickly and skilfully pluck an attacking ant from any part of their anatomy.
The strangest of all the tenants were the tiny, amber-colored roaches which clung frantically to the heads of the great soldier ants, or scurried over the tumultuous mounds, searching for a crevice sanctuary. They were funny, fat little beings, wholly blind, yet supremely conscious of the danger that threatened, and with only the single thought of getting below the surface as quickly as possible. The Attas had very few insect guests, but this cockroach is one which had made himself perfectly at home. Through century upon century he had become more and more specialized and adapted to Atta life, eyes slipping until they were no more than faint specks, legs and antennæ changing, gait becoming altered to whatever speed and carriage best suited little guests in big underground halls and galleries. He and his race had evolved unseen and unnoticed even by the Maxim policemen. But when nineteen hundred humanly historical years had passed, a man with a keen sense of fitness named him Little Friend of the Attas; and so for a few more years, until scientists give place to the next caste, _Attaphila_ will, all unconsciously, bear a name.
Attaphilas have staked their whole gamble of existence on the continued possibility of guest-ship with the Attas. Although they lived near the fungus gardens they did not feed upon them, but gathered secretions from the armored skin of the giant soldiers, who apparently did not object, and showed no hostility to their diminutive masseurs. A summer boarder may be quite at home on a farm, and safe from all ordinary dangers, but he must keep out of the way of scythes and sickles if he chooses to haunt the hay-fields. And so Attaphila, snug and safe, deep in the heart of the nest, had to keep on the qui vive when the ant harvesters came to glean in the fungus gardens. Snip, snip, snip, on all sides in the musty darkness, the keen mandibles sheared the edible heads, and though the little Attaphilas dodged and ran, yet most of them, in course of time, lost part of an antenna or even a whole one.