9. The Birth of the Termite Community
Up to the present we have observed the termites and the termitary from without. We will now study the termitary and the growth and life history of the termites from within the nest. Every step will prove a surprise; we will see many things which appear incredible. The termite differs in every respect from all other insects. Morphologically there is little in nature which reminds us of the termite. Their ontological development is a constant surprise; phylogenetically one must look in the ocean for an analogous circle of development. The entomologist who made the acquaintance of the termite for the first time, would be justified in thinking it to be an immigrant from a different planet.
To mention one thing only -- the wings. Where can one find in nature an organism which during its own lifetime will yield up the mightiest of all weapons in the struggle for life -- its wings? This abandonment of wings is an example of the surprises with which the termite constantly provides us.
I give some illustrations of the different inmates of a Transvaal termitary. One can scarcely believe that they are the children of one father and mother. We have seen how the kings and queens leave the nest in swarms; how they must fly to unlock their sexual life; how the queen sends a signal; how both sexes discard their wings as soon as they reach the ground after their one and only flight. The development of the wings is very interesting. In the sexual type one can see the wing-buds quite early in life. When the insect has shed its skin for the last time and is full-grown, the wings begin to grow from these buds with a kind of hinge which allows for the greatest possible range of movements. It is from this hinge that the insect breaks its wings with a lightning-like movement. She takes hold of the wing-buds with the nearest pair of legs, which appear to be specially adapted for this purpose, shifts them along the bud until they reach the hinge, and detaches the wings.
(Trinervitermes magnified.) King and Queen at time of flight. Perfect insects with fully developed eyes, wings and sex organs. Colour: Dark brown, with red marking. Highly pigmented. Functions: 1. Reproduction. 2. Analogous to motor and sensory centres of brain in higher animals.
(Trinervitermes magnified.) Etiolated, newly hatched termite. Colour: White. All classes and both sexes are found. Sex organs rudimentary, disappearing as development proceeds. Entirely blind. In some individuals rudimentary pigmented spots are found in place of eyes. These, too, disappear. In others, rudimentary wing buds appear, which never develop.
When they have been shed, one can find no wound to indicate the spot of attachment, as one might expect. There must be some organic union, there must be some attachment to the central system which enables the wings to be set into motion. But. there is no sign of this immediately after the wings are detached. How so complicated an organ, which is so powerful and which is under complete control of the insect, can give so little evidence of organic union with the body remains a mystery. One moment the insect is flying, a moment later the wings are detached, yet one finds no evidence of a lesion.
Another point of interest. The insect appears to be able to discard the wings by a voluntary movement of the wing itself. Before flight has taken place, she will struggle to free herself if she is held by the wings, without the wings becoming detached. If, however, she has experienced the sensation of flight, even one movement of the wings appears to be sufficient to satisfy the instinct, then she will discard the wings in one's hand. The observer must understand that it is absolutely necessary for her future life that she shall at least experience the impression of flight. If she has not this, she simply dies. Then she will never become a queen, her sexual life is ended. Sometimes even the struggle for freedom as her wings are held is sufficient to satisfy the instinct. Rapid and continuous movement of the wings while the insect remains stationary on a twig without actual flight through the air, also appears to satisfy occasionally. But these occurrences are more in the nature of exceptions. As a, rule, there is complete frustration sexually if the insect has not flown and discarded her wings.
The king and queen look exactly alike and cannot be distinguished apart with the naked eye. They are the only perfectly formed insects in the termitary. They have fully developed eves and although they were born and reared in darkness, they are highly pigmented. Black, brown and red colourings are found, which never appear in their children, except of course the future kings and queens.
The sexual organs are fully developed. Any natural means of defence is surprisingly lacking. There is probably no insect in our land which has so many natural enemies. One finds the true ant, not the termite, walking round boldly in the daylight, for only reptiles, such as frogs and lizards, which have no sense of taste, try to eat them. Their defence consists of an acid which is secreted for the purpose, and also an indigestible outer covering. So effective apparently are these methods of defence that we find certain beetles taking on the form of large ants so successfully that most animals are deceived by them. The unfortunate termite, on the other hand, is eaten greedily by all other animals. It is a remarkable lesson in nature study to watch the flight of the termites in uninhabited parts of Central Africa. Within a few minutes the surface of the earth is seething with living creatures coming to the feast. Out of the earth crawl frogs, toads, snakes, lizards and other reptiles. From where they receive the news I cannot tell. Even the tortoise appears. Other insects, crickets, beetles, centipedes, spiders, scorpions swarm in the grass. In the water, just below the surface, one sees hundreds of fish and turtles. Out of the bushes slink jackals, cats, meercats, apes and monkeys. There is a temporary truce, except as regards the unfortunate flying termites. They appear to be going to fly merely to die. One begins to understand why nature produces them in such millions, notwithstanding the fact that each pair may be the origin of millions more. Every pair is necessary, because the slaughter is immense. One realizes now why the royal pair are in such a tremendous hurry after they have flown and discarded their wings. The only method of defence the flying termites make use of is flight after dusk. In this way they escape at least the birds which fly by day. But even this may not always happen. Sometimes the, flight begins too early and in the twilight hundreds of hawks gather. The night hawks, owls and other night birds continue the feast into the darkest hours of the night.
One realizes that in this case there has been a displacement of the natural means of defence. What the individual king and queen have lost as regards natural means of defence is compensated for by the defences of the composite animal, the termitary. As soon as the community is formed, the termites never again appear in the daylight, except when injury necessitates this, and even then not in great numbers. However far they may have to go in search of food, and sometimes it may be hundreds of yards, they make underground passages in all directions, and the food itself is temporarily covered with cells and earthwork, making it unnecessary for any individual to appear in the open.
The same thing occurs with all other psychological characteristics and urges -- they are shifted from the individual to the community. The individual termite is without feeling. For him there is no more pain. The injury of a group of termites, however, is felt as pain by the community. The same thing occurs in the human body. The liver is incapable of feeling an injury. It is the human being, the composite animal, which becomes aware of the injury to the liver, as pain.
(Bellicosus magnified.) Queen. Beginning of second stage of development. Functions: Female element in reproduction. Sensory and motor of 'brain'. As in the higher animals, the female element of the termitary undergoes periodical metamorphosis and has a far greater ontogenetic development than the male.
(Bellicosus magnified.) Queen substitute. Similar to Queen or King type, except that the wings do not develop. Function: Sometimes used temporarily as substitute for king or queen. Both sexes found.
Neither does the individual termite feel hunger or thirst. If there is a famine, or if water begins getting scarce, the suffering as such is felt only in the queen's chamber.
The mightiest urge of all, the sexual urge, does not exist in the individual. It has been set free from this irksome tie. The only vestige of self-government which appears to exist amongst the termites are the food, wound and danger signals which are sent out by the soldiers and answered by the workers. But this is no proof that the individual termite possesses a separate psyche. Apart from the power of locomotion, there is no vestige of this psyche. All actual motivations are directed by signals from the queen's chamber.
These signals cease immediately the queen is destroyed and all directed activity ceases, even in the outlying sections of the termitary and even when these sections have been completely isolated over a long period by a metal plate. This seems proof that the group movements, too, are directed by the queen, the brain of the termitary. The king and queen, deep in the absolute darkness of their chamber, bear in their persons two widely diverse functions, the mental and the sexual. The palace chamber is analogous to the skull in higher animals. Even the substance of the queen's body is reminiscent of the brain of mammals. All that is entirely lacking are the nerves which play such an important role in the physical economy of the more highly developed animals.
Having come to the conclusion that the termitary is a composite animal, the observer expects to find some trace at least of structures corresponding to nerves. A little consideration will enlighten one as to the reason why nothing of the kind is found. The most important function in man, for instance, of the nerves, is that of initiating and controlling movement to carry impressions from the sense organs to the brain. On the other hand there are innumerable movements and functions in the human body which are directed and influenced by the brain without being actually linked up by nerves. I mentioned before this influence-at-a-distance which is found all over the body. The work and movements of the blood corpuscles, for instance, are set into being by an influence which is not material; so too are the special functions of the vital organs. The influence which streams from the queen is something intangible and similar to the influence-at-a-distance which directs so many functions in highly developed animals.
In a later chapter I will show how this mysterious influence has the power of penetrating all ordinary materials. For instance, it penetrates quite easily the thickest obtainable galvanized iron plates. Distance, however, lessens the power of the queen's influence. One may imagine Nature addressing the queen thus, after her short flight:
'Beloved, you are going to suffer a great loss. Instead of living in this glowing sunlight, you are going to spend your days in absolute darkness. Instead of the citizenship of the wide veld, instead of the freedom of the air, of mountains, trees and plains, you are going to spend your days as a prisoner in a narrow vault, in whose confines you will be unable to make the least movement. The annual return of the love season, the search for your beloved and the happy finding of your home and all the happiness bound up in this periodical stirring of the soul, of all this you are to be deprived. But in place of all this, you yourself will become a far more important and wonderful being. Although you will apparently be an immobile shapeless mass buried in a living grave, you will actually be a sensitive mainspring. You will become the feeling, the thinking, the seeing of a life a thousand times greater and more important than yours could ever have become. Above all, I will give you protection. The million dangers, the million enemies which threatened your life on every hand, will in your new life fling themselves in vain against your armour.'
It was this need for protection which caused the development of the termitary. As individuals the queen and her subjects are the most threatened of all insects. As individuals, in an unprotected environment, the race would never have survived. As a composite animal, the termitary is very nearly perfectly protected. External wounds, destructive attacks which destroy the whole visible form of the termitary, do not touch its real life, which goes on as usual as though nothing untoward has happened. The wounds are merely repaired. The queen herself, as brain of the organism, is as well protected as the human brain in its skull. There are very few enemies which ever prove a real danger to the queen. One of the largest is the ant-eater; some of the most insidious are groups of beetles, which at times completely devastate a weakened termitary. This latter instance is analogous in every respect to the attack on the human body by pathological organisms. The termitary becomes diseased and dies.
Has the queen paid too dearly for protection? Nature answers this question in a different way from that in which we, or the queen, would.
'What matters it to me how much or how little is paid for the privilege of my protection? How much happiness is lost and how much misery the new life entails is of no importance. What do I care for the individual? The race is safe, rejoicing, inexterminable. The individual must always pay, and no price is too high.'
One realizes why development has taken this peculiar course, why at all costs the queen must remain immobile, why she has been imprisoned in a cell and has lost all power of locomotion. If she is the brain of the organism, that makes it all the more necessary for her to remain stationary in one place. The duplicate functions of the queen, mental and sexual, make matters more complicated. Movement appears to be an integral part of all sexual functions in nature. There seems to be a definite conflict here, but the development of the termitary has solved the problem. I shall not enlarge on this subject here. The student of nature will be aware of what happens, and even the uninitiated will find the solution if he compares this duplication of function in the termites with the same less developed complex in the bee queen. In the latter the sexual functions are the most important and the result is that the danger of the queen on her wedding flight becomes a danger to the whole hive. The termite queen is never again exposed to such danger, once the community is formed and she has been rendered immobile.
The human observer who watched the flight of the queen, who saw the glad meeting of the two sexes, who perhaps even lent a little human aid gives a sigh of relief when eventually the threatened pair find shelter in the protective lap of Mother Earth. Now at last they must be safe. Alas! not yet. There is another great danger which threatens the birth of the new community. In our land it is a merciless enemy -- we call it Drought. The termites must have water, more water, and still more water. As ninety per cent of their bodies consists of water the greatest part of their labour is concerned with the finding and carrying of water, on which the termitary is just as dependent as the warm-blooded animals are. The king and queen must find water immediately. They obtain this from damp earth. That is why the flight occurs only after heavy rains -- this at least they expect from nature. Sometimes, however, they make a mistake. The first duty of the royal pair is to manufacture an organ for hatching out and feeding the first workers and soldiers. For this purpose a plentiful supply of water is necessary. If the water supply gives out during this initial period, all is finished; it means death to them and to the composite animal. Both king and queen work incessantly, making passages in the direction of moist earth. These generally descend perpendicularly and are the beginnings of the vertical aqueduct -- at least in dry districts. At intervals in these first passages they make, or perhaps find, hollows in the earth and here they make their first termite gardens. Enthusiastic observers of the real ant have called them gardens, so we will continue using the term. They resemble very much our own agricultural efforts.
First the ground is carefully prepared. The fertilizer consists of finely chewed, partially digested vegetable substance, mostly dry wood and grass stalks. Then it is irrigated with water, much water, until the ground is saturated. Both king and queen labour incessantly; they do not rest for a second, nor do they sleep day or night. It is the last time, however, that they will ever be expected to work. The functions which they will fulfil in future can hardly be called work. At last the first garden is ready, deep in a hollow of one of the passages. No ray of light must ever fall upon it, everything is done in inky darkness. This first garden consists of a pat of cell structure and earth-work, and when it is well saturated, the two termites proceed to plant the seeds of a peculiar fungus, which is to play an enormous role in the future life history of the termitary and as such deserves our careful attention. I have said the termites plant the seed. I cannot, however, prove this to be a fact, but that is what appears to take place. They walk about on the damp garden and in the shortest possible time necessary for germination and development, the fungus springs up, in the form of a white mould. I have found the hyphae and spores of the fungus on jaws and legs of flying termites immediately after they have left the termitary. It appears as though they purposely carry the seed to plant in the new nest. One also finds spores on termites which have nothing to do with the gardens. In the neighbourhood of large termitaries one finds the spores in great numbers in the underground hollows and passages. They are spread by water, by wind, by worms and by insects. It is possible, therefore, that the spores might show themselves on the specially prepared ground, without the assistance of the termite. The termites, however, do far more incredible things than the planting of these spores would be. So we will take it for granted that they do carry the spores and that the planting of the gardens is intentional.
Whether they do actually plant seed or not, there is certainly no question about the fertilization and irrigation of the gardens. The passage which leads to the water is constantly being deepened. While the damp earth is being excavated, the moisture is stored in the bodies of the two insects. The garden is irrigated with drops of a clear shining liquid, the same in all respects as that which is used for many other purposes later on by all the groups.
In this early garden, the queen lays her first eggs. At this stage she is still able to run about quickly and work actively. In the meantime wonderful things are happening to the fungus garden. The two insects do something to the mycelium of the plant which retards growth and development and at the same time the temperature of the garden begins to rise astoundingly.
The origin of this rise in temperature seems at first inexplicable. It cannot come from the termites, for their bodies are always at the same temperature as that of their environment. It comes from the garden, which functions as an incubator and is responsible later for maintaining the heat of the composite animal. The normal temperature of the termitary taken in the queen's cell is from four to six degrees Fahrenheit higher than the normal temperature of a human being. There is little doubt that most of this heat is generated by the fungus-beds. It is well known that in all fungi rise of temperature takes place when the spores ripen. In the gardens of the termitary the temperature is kept raised to a certain degree by something the termite does to the plant which retards growth and development at the very stage when the fungi generate most heat. The garden, however, is more than incubator and nursery. The production of heat is a very important function, certainly, but in addition to this the garden becomes the stomach and liver of the composite animal.
By constant and rapid metabolism not only nutriment, but also digestive juices are assembled in the plant. Under the microscope and chemically one can find oil, protoplasm, glycogen, carbohydrates, proteid crystals, gum, alkaloids, and different enzymes, similar to those in the human body, which break up complicated sugars into dextrose and levulose, which reduce ordinary sugar to alcohol and carbon. The only substance we find no trace of is starch.
The circle or digestion takes place in this way: The workers and the king and queen in their first stages are the only termites in the nest which can masticate wood, grass-stalks and other coarse vegetable matter, and partially digest it. No other group in the termitary is able to absorb or digest anything but fluid. When the kin and queen in their first stage, or the workers, have partially digested the food, it goes to the stomach and liver -- the so-called gardens. Here it is further digested and changed by the fungi and the digestive juices I have mentioned. It happens in just the same way as in the human body. When the stomach and liver have prepared the food, it is taken up by the workers and soldiers in liquid form and becomes part of the whole circulation.
More than half this predigested food is used for building purposes. When one touches a newly built tower, one's fingers become sticky. With a magnifying glass one can see how each worker rolls the tiny grain in its jaws, coating it with the sticky fluid before placing it in position. This is the fluid which is obtained from the gardens. The water necessary for the production of this fluid is being constantly supplied to the gardens by a stream of workers, whose sole function appears to be this and the sowing of seed. If a vertical aqueduct is present, one finds a hollow every two or three feet, in which a small garden is cultivated. During severe droughts, water is constantly carried to the deepest gardens and the fungi there are kept alive. The great advantage of having little fungus beds so near to the water is obvious, as it spares the termites much labour. From these gardens the seed is carried to new ones, or to replant those which were killed by drought. These smaller gardens are never used for any other purpose; you will never find them used as nurseries, as is the case with the large gardens.
Another function of the fungus gardens appears to be the isolation of colour. A dark-red colouring material can be obtained from them. It appears, therefore, that the termites find the red colouring matter of their bodies prepared for them by the gardens. The babies are entirely colourless, as one would expect from insects born in utter darkness. One would expect that they would never become coloured in the absence of light, and as they continue living in darkness it is difficult to explain the presence of all the brilliant tints. These, however, come from the gardens. The babies are white as milk until they are fed on the fungus fluid. Then only do we find their bodies assuming the blood-red colour of the adults.
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