Versamelde werke

6 White Ants and Their Communal Mind

We in South Africa recognised early that there is probably no organism which affords better opportunities for research into the functions and attributes of the communal mind than the white ant. It was this that induced a study lasting several years.

Fortunately, we had better opportunities for research than most naturalists in other countries. The opening - the dissection, so to say - of an ant-nest is at the best a difficult and expensive operation. In drought-stricken regions it often requires the expenditure of time and money to an extent beyond the reach of independent and financially-unsupported workers. Here in South Africa the destructive activities of certain species of white ants had called into

[p. 1228]

being a profession - that of ‘ant destroyers’. These men undertook to eradicate white ants in house, garden or orchard at so much per queen. Most of them became wonderfully expert in locating the queen's hollow and in reaching her with a minimum expenditure of time and labour. All they did in fulfilment of their contract was to find and produce the queen. It was the work of these men which afforded me an opportunity, over several years, of seeing more termitaries opened than most research workers ever have a chance of doing. The opportunities for experimental research were also unlimited.

I myself think that our most important achievement was the discovery and determination of the psychological functions of the queen. Strangely enough, as far as I know, no other naturalist seems to have suspected their existence before. I think this was due chiefly to the fact that most workers in this field were systematists rather than comparative psychologists. Once the psychological functions of the queen were known and defined, explanations were readily found for many hitherto insoluble problems of behaviour. It was, of course, the fact that removal of the queen (and of royal substitutes among certain species) resulted in the destruction of the whole community that put us on the track of her hitherto unknown and unexplained functions; and the concerted labour of soldiers and workers afforded opportunities for experimental confirmation of both the existence and extent of these functions.

The following is, briefly, the early life-history of the termitary which, generally speaking, applies to most species.

The community consists, first of all, of the king and queen. The queen is enclosed in a stone-hard cell from which she can never again emerge, in the deepest and darkest part of the nest. (In some species the queen remains at liberty.) The king does not change and is always at liberty, but never leaves the central dark hollow where the queen is confined. It is the best-protected space in the nest, just as, in higher animals, the brain is the best-protected centre of the organism. The king and queen are perfect insects. They are sexually perfect, possess eyes, and at one stage of their existence they are winged and can fly.

The perfect winged male and female insects sometimes remain in the nest for two or three years. They are continually in contact, but there is never any manifestation of sexual behaviour.

All instinctive behaviour in nature consists of a number of ‘steps’ which recur in regular succession. If one step is omitted the whole process is disorganised. I found that all processes of instinctive behaviour are inaugurated by a ‘key’.

In the case of the sexual complex, this ‘key’ consists in sound, perfume or colour. Without this key, the resulting complex cannot be inaugurated. Thus birth pain is the key which sensitises the maternal instinct in all nature. With-

[p. 1229]

out birth pain in some form there can be no maternal instinct. I found that by preventing pain by the use of a general anaesthetic the maternal instinct in mammals is entirely excluded. Man, of course, has in all these respects become ‘unnatural’.

In the white ant the sexual sense is inaugurated by an actual flight through the air. It might be a mile or just a yard, but without this flight there is no subsequent sexual behaviour. If the wings are removed before the flight is due, the insects creep away to die, and even actual physical contact of the sexes results in no sexual behaviour. The sexual behaviour of the white ant (like all psychological complexes) does not concern the two sexual individuals alone. It is a manifestation of the entire community - as of one self-contained organism. When this sexual flight takes place there is intense excitement, in which every blind soldier and worker share. As in higher animals, rage is inseparably connected with this activating of the sexual sense. The soldiers visiously attack every intruder to the nest. Inside the nest there is continual and feverish excitement and movement, and the temperature is raised a degree and a half Fahrenheit in the deeper portions.

I think I was the first observer to describe what takes place during and after the nuptial flight. After a short or long passage through the air the queen alights on the wet ground. She selects an open space and, with a movement so rapid it cannot be followed by the naked eye, she divests herself of her wings. One moment you see her walking with her four beautiful, fairy-like wings neatly folded along the body; the next instant she walks out of them more suddenly and apparently with less effort than the modern girl gets out of her skimpy frock. For this one flight through the air, which might be a thing of yards in space and seconds in time, nature has developed these complex and beautiful wings. She will never fly again. She will never taste the delights of the open air, of light and wind and absolute liberty. Henceforth she will live in total and perpetual darkness, shut up in a cell and deprived of all possibility of the slightest movement.

The moment the queen has cast off her wings, the next stage of her behaviour starts - mysterious as it is interesting - and it is this stage in her life history that has remained practically unexplored. She selects an open space and there assumes an attitude of absolute immobility. Three-quarters of her body is raised perpendicularly into the air. Under magnification a slight movement, resembling the breathing of higher animals, is sometimes visible. It is only by carefully watching the further course of events that the enigma of her behaviour can be solved. She is signalling.

These insect signals can almost be said to constitute a separate branch of comparative psychology. They consist either of colour, sound or perfume, and in a great many instances lie outside the reach of all human sense organs. These

[p. 1230]

sexual key-signals run through the whole world of organised matter, and vestigial remains still exist in human psychology. The fashionable lady who covers her person with all the colours of the rainbow and perfumes of Araby will be astonished to learn that these are unquestionably sexual in origin. Her perfumes are basically the perfumes employed throughout the animal world: civet, musk, ambergris (wrongly termed a product of disease) and the scents of flowers are all sexual signals. The mysterious signal of the queen ant is a perfume. It is beyond the reach of the average human sense of smell, but I proved experimentally that it is well within that of the dog. It is possible that sound may also be employed. The signal reaches the male in the air. He settles as near her as the wind and other conditions will permit, and immediately ‘steps’ out of his wings, just as the queen did previously. Then commences a frenzied hunt, which always results in the speedy finding of the immobile queen. When he reaches her, he touches her very gently with his forelegs and at once she is also transformed into a machine of dynamic activity. Without apparently taking the slightest notice of the king, she rushes off in what is apparently a frantic search. There is need for speed, for the pair are surrounded by a million foes. The king follows immediately behind her, touching her every now and then with his antennae. Quite clearly she is the directing power, and she remains this for the rest of their lives. She is searching for a suitable spot of soft wet earth, and frequently takes a considerable time before she is satisfied.

When she does eventually reach a spot that satisfies her, the pair commence digging side by side, and in an incredibly short space of time are lost to view underground, from where they are never again to emerge into the light of day. This is the beginning of the new nest. By careful manipulation, it is possible to induce a couple to select a previously prepared underground hollow provided with a peephole and an illumination aperture. It is then possible to catch a few glimpses of the profoundly interesting events which follow the occupation of the new nest. If the couple belong to a ‘gardening’ species, a fungous growth is at once prepared and planted. The spores for the purpose are brought from the home nest. In this fungus garden the first eggs are laid and the larvae hatched. These are the first soldiers and workers - insects so different from their parents and from each other that no naturalist, if he did not know by observation, would ever classify them as belonging to the same species.