1. The Beginning of a Termitary
SOME years ago an article about 'White Ants', as termites are commonly but incorrectly called, appeared in a South African journal. Almost everything that naturalists tell us about these insects is important and interesting, and Dr Hesse's article was exceptionally so. But the article also made another fact clear; how very little is done in our land to study the behaviour of animals, and how much has been done and is being done in other countries. Everything that Dr Hesse told us was the result of long and patient observation in America and Europe. None of his facts was exactly relevant to our South African termites.
The life-history of most of our South African ants and termites is in every respect just as wonderful and interesting as anything that has been discovered in South America. Over a period of ten years I studied the habits of termites in an investigation into animal psychology. I then realized that such observation reveals new wonders every day. To mention one instance, the functioning of the community or group psyche of the termitary is just as wonderful and mysterious to a human being, with a very different kind of psyche, as telepathy or other functions of the human mind which border on the supernatural.
When one wishes to write of all these wonders, one is bewildered by the embarras de richesses. It is hard to know where to begin.
I want to tell you about the commonest of our termites or 'white ants', and what I am going to relate may be observed by anyone who wishes; he may even discover new wonders. Most of these facts have not been published before; indeed, I do not think they have been discovered by scientists.
The common termite which is so destructive to wood of all kinds, and builds 'ant-hills' or termitaries on the open veld, is known throughout South Africa. I will tell you a little about the beginning of its community life.
The beginning of a termitary dates from the moment when the termites fly, after rain and usually at dusk, in order to escape their innumerable enemies. Even here we see a remarkable instance of the wonder of instinct. The termites beginning their thrilling flight know nothing about enemies. They have never been outside the nest before. The peril of existence is to them a closed book, and yet nine times out of ten they do not fly until the birds are safely in their nests.
These flying termites are at least twenty times as big as the others of the nest, and quite different in colour and form. You must consider a termitary as a single animal, whose organs have not yet been fused together as in a human being. Some of the termites form the mouth and digestive system; others take the place of weapons of defence like claws or horns; others form the generative organs. These flying termites are the generative organs of the colony. Every one of these winged insects is a potential king or queen. The four beautiful wings have taken months to develop and grow to perfection; months elapse -- or even years in very dry districts -- before an opportunity for flight occurs. They will never fly until there has been rain, and the reason is obvious. After the flight they must seek immediate shelter in the ground, and when the ground is hard and dry this is impossible.
Soldier and worker termites
Follow the flight of the termites carefully from the moment they emerge from the nest. They crawl out of a little opening, thousand upon thousand. There is obviously much excitement in the termitary. Sometimes the flyers are escorted to the opening by workers and soldiers. The first impulse of the flying insect as it emerges is to try its wings. It flutters and essays to lift itself into the air. If it fails, it climbs a grass stalk and takes off from this height. But fly it must, even if it is only for a few inches. You will understand presently why this is so essential, just as necessary as the preservation of its life, and therefore it takes just as much trouble to fly -- even more perhaps, for the urge is greater -- as to protect itself from enemies.
The watcher will soon become aware that the object of the flight seems to be to spread the insects over as large an area as possible, as some plants disseminate their seed. Some of the termites rise high into the air and travel for miles before they settle; others sink to the ground only a stride or two from the old nest. But far or near, fly they must, or the sole object of their existence is frustrated.
Let us watch one of the ants which has flown and settled in the grass near at hand. We will suppose it is female -- the two sexes cannot be distinguished with the naked eye. The first thing she does is to discard her wings. This she succeeds in doing by a lightning-like movement -- so fast that we cannot follow it with the eye. One moment we see her with her wings intact, the next moment she steps away, and her four wings are lying on the grass -- she is much, much quicker than a woman who discards her evening gown and hangs it over a chair. It took months for her wings to grow. For years perhaps she has lived in subterranean darkness, in preparation for this one moment. For a period of three seconds, for a distance of perhaps three yards, she enjoyed the exquisite thrill of flight and with that the object of a great preparation has been furfilled and the fairy-like wings are flung aside like a worn-out garment.
Immediately the wings are discarded she walks about rapidly for a few seconds. You become aware that she is seeking a suitable place for some further purpose -- but you do not know what the purpose can be, and her immediate behaviour does not clear things up for you. You must watch patiently if you wish to discover what she intends doing. When she has found a suitable spot, she does a very peculiar thing. She comes to rest on her fore-feet and lifts three-quarters of the hinder part of her body into the air, and she remains stationary in this position, as still as if she were merely the statue of a termite. If you become impatient and walk away the secret of the flying termite will remain a secret to you for ever. What is she doing? She is busy sending a wireless SOS into the air. Be patient a little longer -- there are only very few people who have witnessed this miracle. What does the signal consist of? I think I know, but I doubt if you will guess what it is. Only if you have made a study of the signals of insects will you find the clue. You think, of course, of some sound which cannot be heard by the human ear. You may know how our little South African toktokkie beetle (a beetle of the genus Psammodes) knocks in similar circumstances. No, the termite's signal is not a sound. One can prove that by experiment. We will content ourselves for the moment with the fact that the signal consists of something far and away beyond our own senses, and yet the male becomes aware of it over incredible distances! How does this happen? Well, it does happen, and our female is a very modern young woman, not too shy to make the first move in love-making. If you wait long enough you will presently see another termite come flying through the air, and you will notice that although his flight appears awkward and almost involuntary, yet he can steer a course and choose a direction even against the wind. The male sinks to the ground sometimes a yard or two from the place where the female is standing motionless in her curious posture. As soon as he lands he makes the same lightning-like movement which we have already seen in the female, and there on the ground lie his wings, too. His haste is terrible and irresistible. Over and through the grass he crawls, so fast that we can barely follow him with our eyes. He is looking for the originator of the signal which he received high up in the air. Within a few minutes he has found her. She has been motionless all the while, with her body hoisted aloft, but the instant the male touches her with his antennae, he infects her with his own excitement. She begins to run away as fast as her legs will carry her, and immediately behind her comes the male. They are now beginning the final search -- they are house-hunting, and this the male leaves to his wife. It must be a good house, for they will live in it for a long time. And with the finding of their home and the digging of the front door we will leave the happy pair for a while.
There are even stranger things connected with this little drama, of which the inexperienced observer will not become aware. I spoke of the urge to flight. Listen carefully. If those two termites had not flown, none of the events we have watched would have occurred. Instinct is something which only works step by step. If you destroy one step or omit it, then the whole thing collapses. Nature wishes the 'white ant' to spread. If the nests are too close together it would be bad for the communities, therefore they receive wings and must fly. But flight is only one step in their sexual life; if this step is omitted, their sexual life and their very existence ends there and then.
For as long as two years the two sexes may live in the same nest after they have grown wings. They are in constant touch with each other but there is not the least evidence of any sexual life. They must crawl out of the nest, they must fly, must settle and lose their wings, then and then only, and then immediately, sexual life begins. If you prevent them flying and break off the wings, both male and female die without any further attempt to become progenitors of the race. The length and distance of the flight is of no importance; it may last hours or only a second; it may cover miles or only an inch. But the force which we call instinct commands -- you must pass through every stage, you must take every step, or you are doomed. If you take a male and female just as they are emerging from the nest and place them beside each other, even in the closest contact, you notice that they take not the least interest in each other. They struggle to get away from each other. Let the female fly a few inches and the whole process which we described is carried out to a finish. Let the male circle round even once, then force him to land near the female, then and then alone, will events take their normal course. A second in time, three inches in space, one flutter of wings, are to the termite a gulf as wide as infinity dividing two kinds of existence. To us it may appear only a small dividing line, but the insect may not overstep it, not even with human assistance.
2. Unsolved Secrets
THERE is much to be told about the building of the termitary, but I wil1 confine myself to behaviour which is important for purposes of comparison. All behaviour is of importance to the psychologist. Behaviour is psychology -- at least it is all of the psyche we know or can study. For purposes of comparison, for comparative psychology -- especially if you begin at the top of the ladder with the apes -- the field at our disposal is not very large.
Upon the king and queen themselves falls the task of feeding and attending the first children. After the latter are fullgrown they take upon themselves all the work of the community. In the meantime the queen grows larger and fatter by the hour. Her small neat body vanishes in increasing layers of fat until at last it becomes an unsightly wormlike bag of adiposity. And to heighten the tragedy, her mate, in addition to having the blessing of almost the only dolce far niente existence known to nature, appears to have discovered the secret of eternal youth. He remains as beautiful and active and young as he was on his wedding flight. But if you look at her, an immovable disgusting worm, it seems impossible to believe that she ever fluttered in the air on fairy wings. We could hardly blame his majesty if he began casting an eye at some other female a little less repellent. If you fear this, however, you will be pleasantly surprised. His attachment to his queen seems to keep pace with her own growth. If you lay open the palace cavity, he rushes round in consternation, but always returns to her side. There is no question of saving his own life in flight. He clings to her gigantic body and tries to defend it, and if the ruthless attacker so wills, he dies at her side. What a wonderful example of married love and fidelity, which can survive this terrible change of his beloved to a loathsome mass of fat!
We often speak metaphorically of a queen as the mother of her people. This the termite queen is literally. She is the only mother of the millions which form the community; every individual is born out of her. Naturally she is absolved from all duty in the nursery. All she is expected to do is to keep on laying an endless stream of eggs, because the daily loss of workers and soldiers is enormous, notwithstanding their excellent methods of defence. Mother Nature is not perturbed about the death of a thousand individuals, when she has had the foresight to make certain of an unending supply.
I am now coming to a stage when in actuality every termitary differs in its growth, but for our purpose we will suppose that the environment of our nest has been such that development is entirely normal and not subjected to any disturbing outside influences. The first workers begin to build a palace for the queen. Deep below the surface of the earth, from three to six feet, they prepare a hollow chamber. As years go by this is gradually increased in size, and the earth which is excavated is taken to the surface and used to form the thick defensive crust. In this hollow chamber the queen is placed. It fits her so well that one is inclined to think that it has been built around her. I do not think this actually happens, but now I come to a stage when almost every conclusion is bound to be mere guesswork. No human eye has ever seen what actually takes place. No one has ever discovered a way in which to watch the termites at work in the queen's chamber, for they work in pitch darkness and to let light into the chamber is as great a handicap to the termites as the sudden destruction of the sun would be to us. We cannot see in complete darkness.
Winged adult termites
The queen continues growing until, compared with the ordinary termite, she reaches a gigantic size, and becomes an immobile mass, still as a log. The only part of her which gives any sign of life is the little head, which remains unchanged. If you dissect the skin and body carefully and examine it under a microscope, you will be convinced that during her later stages of growth the queen is unable to make any voluntary movement, except of course of the head. You make think she could move like some worms do, by contraction and expansion. But you will find that no part of the body behind the head can be controlled by what was once an intricate central nervous system. Nor do I think that there can be any question of her regaining the power of movement temporarily, as for instance by emptying the sac for a while. I certainly have seen no indication of this. Besides, the very nerves in the body have changed into fluid. Both these theories, therefore, that the queen is able to move by contraction and expansion, or that she gains a temporary power of movement, must be discarded.
To continue with the queen's life-history, her first palace is a cell made of termite earth which rapidly becomes as hard as cement. Usually she just neatly fits into it. She is always much too huge to use the door of the cell as entrance or exit. If you wish to remove her you must break down the cell. The king and the workers, however, can come and go quite easily. She is fed and the eggs which she never ceases laying are removed to the breeding grounds by workers appointed to this task. The king apparently does nothing. He appears to be a mere hanger-on in the palace. Still the queen goes on growing. Here in her first palace- she has not attained one-third of her eventual size. At last she very nearly fills all the available space in the cell. There is barely room for the tiny workers to carry the eggs away across the insensate bulk. A terrible tragedy appears to be imminent -- it reminds us of the question: what will happen if an irresistible force meets an immovable mass? The human observer is helpless at the threat of this terrible fate. In spite of all his knowledge and intelligence he is unable to help in any way. But actually termites have never worried about it at all. They had a solution ready -- a very simple one. Just before her majesty finally outgrows her cell they build a second one, half as big again as the first. It is parallel and adjacent to the first, just as hard and with just such a narrow door. The queen is then removed and placed in the second cell where there is space for her to grow for perhaps another year. So she gets transposed from cell to cell until there have been about six changes with the queen in the last and biggest. The chamber doors are always equally small much too small for the queen to come or go by.
We must clearly establish another fact which makes the whole matter even more complicated. One could easily prove by measurement that the queen's subjects could not possibly move her. The lifting power of one termite can be estimated fairly closely, and the area of the queen's body available for workers to grasp during lifting can be measured. During the later stages it would need thousands more termites to lift her than there is available grasping space for the body.
We present to you the following facts:
The queen is incapable of movement.
The doors of the cell are too small for her to come or go by.
The insects cannot lift her.
Yet she vanishes from one cell to appear in another.
The only explanation that seems feasible is that there are several queens and that it is not the same one each time. If the first gets too big for her cell, she is killed and eaten and then the workers carry a potential queen into the second cell where she develops into a queen. The only intelligent explanation, perhaps, and very simple, now we have thought of it.
The only pity is that it is not true. We have been deceived by the analogy of the bees, which make queens, kill, and move them. It is quite an easy matter to mark the termite queen and so prove that it is the same queen which gets moved. I have tested many theories brought forward by friends who have studied entomology, but have never found one which coincided with all the facts. Perhaps one day a future Fabre will discover the truth.
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