As a result of this we can witness, in many animal species, elaborate threat rituals and combat ‘dances’. The contestants circle one another in a characteristically stilted fashion, their bodies tense and stiff. They may bow, nod, shake, shiver, swing rhythmically from side to side, or make repeated short, stylised runs. They paw the ground, arch their backs, or lower their heads. All these intention movements act as vital communication signals and combine effectively with the autonomic signals to provide a precise picture of the intensity of the aggression that has been aroused, and an exact indication of the balance between the urge to attack and the urge to flee.
But there is yet more to come. There is another important source of special signals, arising from a category of behaviour that has been named displacement activity. One of the side-effects of an intense inner conflict is that an animal sometimes exhibits strange and seemingly irrelevant pieces of behaviour. It is as if the tensed-up creature, unable to perform either of the things it is desperate to do, finds an outlet for its pentup energy in some other, totally unrelated activity. Its urge to flee blocks its urge to attack and vice-versa, so it vents its feelings in some other way. Threatening rivals can be seen suddenly to perform curiously stilted and incomplete feeding movements, and then return instantly to their full threat postures. Or they may scratch or clean themselves in some way, interspersing these movements with the typical threat manoeuvring. Some species perform displacement nest-building actions, picking up pieces of nest material that happen to lie near by and dropping them on to imaginary nests. Others indulge in ‘instant sleep’, momentarily tucking their heads into a snoozing position, yawning or stretching.
There has been a great deal of controversy about these displacement activities. It has been argued that there is no objective justification for referring to them as irrelevancies. If an animal feeds, it is hungry, and if it scratches it must itch. It is stressed that it is impossible to prove that a threatening animal is not hungry when it performs so-called displacement feeding actions, or that it is not itching when it scratches. But this is armchair criticism, and to anyone who has actually observed and studied aggressive encounters in a wide variety of species, it is patently absurd. The tension and drama of these moments is such that it is ridiculous to suggest that the contestants would break off, even momentarily, to feed for the sake of feeding, or scratch for the sake of scratching, or sleep for the sake of sleeping.
Despite the academic arguments about the causal mechanisms involved in the production of displacement activities, one thing is clear, namely that in functional terms they provide yet one more source for the evolution of valuable threat signals. Many animals have exaggerated these actions in such a way that they have become increasingly conspicuous and showy.
All these activities, then, the autonomic signals, the intention movements, the ambivalent postures and the displacement activities, become ritualized and together provide the animals with a comprehensive repertoire of threat signals. In most encounters they will be sufficient to resolve the dispute without the contestants coming to blows. But if this system fails, as it often does under conditions of extreme crowding, for example, then real fighting follows and the signals give way to the brutal mechanics of physical attack. Then, the teeth are used to bite, slash and stab, the head and horns to butt and spear, the body to ram, bump and push, the legs to claw, kick and swipe, the hands to grasp and squeeze, and sometimes the tail to thrash and whip. Even so, it is extremely rare for one contestant to kill the other. Species that have evolved special killing techniques for dealing with their prey seldom employ these when fighting their own kind. (Serious errors have sometimes been made in this connection, with false assumptions about the presumed relationship between prey-attacking behaviour and rival-attacking activities. The two are quite distinct in both motivation and performance.) As soon as the enemy has been sufficiently subdued, it ceases to be a threat and is ignored. There is no point in wasting additional energy on it, and it is allowed to slink away without further damage or persecution.
Before relating all these belligerent activities to our own species, there is one more aspect of animal aggression that must be examined. It concerns the behaviour of the loser. When his position has become untenable, the obvious thing for him to do is to remove himself as fast as he can. But this is not always possible. His escape route may be physically obstructed, or, if he is a member of a tightly knit social group, he may be obliged to stay within range of the victor. In either of these cases, he must somehow signal to the stronger animal that he is no longer a threat and that he does not intend to continue the fight. If he leaves it until he is badly damaged or physically exhausted, this will become obvious enough, and the dominant animal will wander off and leave him in peace. But if can signal his acceptance of defeat before his position has deteriorated to this unfortunate extreme, he will be able to avoid further serious punishment. This is achieved by the performance of certain characteristic submissive displays. These appease the attacker and rapidly reduce his aggression, speeding up the settlement of the dispute.
They operate in several ways. Basically, they either switch off the signals that have been arousing the aggression, or they switch on other, positively non aggressive signals. The first category simply serves to calm the dominant animal down, the latter help by actively changing his mood into something else. The crudest form of submission is gross inactivity. Because aggression involves violent movement, a static pose automatically signals non-aggression. Frequently this is combined with crouching and cowering. Aggression involves expanding the body to its maximum size, and crouching reverses this and therefore acts as an appeasement. Facing away from the attacker also helps, being the opposite of the posture of frontal attack. Other threat-opposites are also used. If a particular species threatens by lowering its head, then raising the head can become a valuable appeasement gesture. If an attacker erects its hair, then compressing it will serve as a submission device. In certain rare cases a loser will admit defeat by offering a vulnerable area to the attacker. A chimpanzee, for example, will hold out its hand as a gesture of submission, rendering it extremely vulnerable for serious biting. Because an aggressive chimpanzee would never do such a thing, this begging gesture serves to appease the dominant individual.
The second category of appeasement signals operate as re-motivating devices. The subordinate animal sends out signals that stimulate a non-aggressive response and, as this wells up inside the attacker, his urge to fight is suppressed and subdued by it. This is done in one of three main ways. A particularly widespread re-motivator is the adoption of juvenile food-begging postures. The weaker individual crouches and begs from the dominant one in the infantile posture characteristic of the particular species—a device especially favoured by females when they are being attacked by males. It is often so effective that the male responds by regurgitating some food to the female, who then completes the food-begging ritual by swallowing it. Now in a thoroughly paternal, protective mood, the male loses his aggression and the pair calm down together. This is the basis of courtship feeding in many species, especially with birds, where the early stages of pair-formation involve a great deal of aggression on the part of the male. Another re-motivating activity is the adoption of a female sexual posture by the weaker animal. Regardless of its sex, or its sexual condition, it may suddenly assume the female rump presentation posture. When it displays towards the attacker in this way, it stimulates a sexual response which damps down the mood of aggression. In such situations, a dominant male or female will mount and pseudo-copulate with either a submissive male or a submissive female.
A third form of re-motivation involves the arousal of the mood to groom or be groomed. A great deal of social or mutual grooming goes on in the animal world and it is strongly associated with the calmer, more peaceful moments of community life. The weaker animal may either invite the winner to groom it, or may make signals requesting permission to perform the grooming itself. Monkeys make great use of this device and have a special facial gesture to go with it, consisting of rapidly smacking the lips together—a modified, ritualised version of part of the normal grooming ceremony. When one monkey grooms another it repeatedly pops fragments of skin and other detritus into its mouth, smacking its lips as it does so. By exaggerating the smacking movements and speeding them up, it signals its readiness to perform this duty and frequently manages in this way to suppress the aggression of the attacker and persuade it to relax and allow itself to be groomed. After a while the dominant individual is so lulled by this procedure that the weakling can slip away unharmed.
These, then are the ceremonies and devices by which animals order their aggressive involvements. The phrase ‘nature red in tooth and claw’ was originally intended to refer to the brutal prey-killing activities of the carnivores, but it has been applied incorrectly in general terms to the whole subject of animal fighting. Nothing could be further from the truth. If a species is to survive, it simply cannot afford to go around slaughtering its own kind. Intra-specific aggression has to be inhibited and controlled, and the more powerful and savage the prey-killing weapons of a particular species are, the stronger must be the inhibitions about using them to settle disputes with rivals.
This is the ‘law of the jungle’ where territorial and hierarchy disagreements are concerned. Those species that failed to obey this law have long since become extinct. How do we, as a species, measure up to this situation? What is our own special repertoire of threatening and appeasing signals? What are our fighting methods, and how do we control them?
Aggressive arousal produces in us all the same physiological upheavals and muscular tensions and agitations that were described in the general animal context. Like other species, we also show a variety of displacement activities. In some respects we are not as well equipped as other species to develop these basic responses into powerful signals. We cannot intimidate our opponents, for example, by erecting our body hair. We still do it in moments of great shock (‘hair stood on end’), but as a signal it is of little use. In other respects we can do much better. Our very nakedness, which prevents us from bristling effectively, gives us the chance to send powerful flushing and paling signals. We can go ‘white with rage’, ‘red with anger’, or ‘pale with fear’. It is the white colour we have to watch for here: this spells activity. If it is combined with other actions that signal attack, then it is a vital danger signal. If it is combined with other actions that signal fear, then it is a panic signal. It is caused, you will recall, by the activation of the sympathetic nervous system, the ‘go’ system, and it is not to be treated lightly. The reddening, on the other hand, is less worrying: it is caused by the frantic counter-balancing attempts of the parasympathetic system, and indicates that the ‘go’ system is already being undermined. The angry, red-faced opponent who faces you is far less likely to attack than the white-faced, tight-lipped one. Red-face’s conflict is such that he is all bottled up and inhibited, but white-face is still ready for action. Neither can be trifled with, but white-face is much more likely to spring in to the attack unless he is immediately appeased or counter-threatened even more strongly.
In a similar vein, rapid deep breathing is a danger signal, but it has already become less of a threat when it develops into irregular snorts and gurgles. The same relationship exists between the dry mouth of incipient attack and the slobbering mouth of the more intensely inhibited assault. Urination, defecation and fainting usually arrive a little later on the scene, following in the wake of the massive shock-wave that accompanies moments of immense tension.
When the urge to attack and escape are both strongly activated simultaneously, we exhibit a number of characteristic intention movements and ambivalent posturing. The most familiar of these is the raising of a clenched fist—a gesture that has become ritualised in two ways. It is performed at some distance from the opponent, at a point where it is too far away to be carried through into a blow. Thus its function is no longer mechanical; instead it has become a visual signal. (With the arm bent and held sideways it has now become the defiant formalised gesture of communist regimes.) It has become further ritualised by the addition of back-and-forth striking movements of the forearm. Fist-shaking of this kind is again visual rather than mechanical in its impact. We perform rhythmically repeated ‘blows’ with the fist, but still at a safe distance.
While doing this, the whole body may make short approach-intention movements, actions which repeatedly check themselves from going too far. The feet may be stamped forcibly and loudly and the fist brought down and thumped on any near-by object. This last action is an example of something seen frequently in other animals, where it is referred to as a redirection activity. What happens is that, because the object (the opponent) stimulating the attack is too frightening to be directly assaulted, the aggressive movements are released, but have to be re-directed towards some other, less intimidating object, such as .a harmless bystander (we have all suffered from this at one time or another), or even an inanimate object. If the latter is used it may be viciously pulverised or destroyed. When a wife smashes a vase to the floor, it is, of course, really her husband’s head that lies there broken into small pieces. It is interesting that chimpanzees and gorillas frequently perform their own m versions of this display, when they tear up, smash, and throw around branches and vegetation. Again, it has a powerful visual impact.
A specialised and important accompaniment to all these aggressive displays is the making of threatening facial expressions. These, along with our verbalized vocal signals, provide our most precise method of communicating our exact aggressive mood. Although our smiling face, discussed in an earlier chapter, is unique to our species, our aggressive faces, expressive though they may be, are much the same as those of all the other higher primates. (We can tell a fierce monkey or a scared monkey at a glance, but we have to learn the friendly monkey face.) The rules are quite simple: the more, the urge to attack dominates the urge to flee, the more the face pulls itself forwards. When the reverse is the case and fear gets the upper hand, then all the facial details are pulled back. In the attack face, the eyebrows are brought forward in a frown, the forehead is smooth, the mouth-corners are held forward, and the lips make a tight, pursed line. As fear comes to dominate the mood, a scared-threat face appears. The eyebrows are raised, the forehead wrinkles, the mouth corners are pulled back and the lips part, exposing the teeth. This face often accompanies other gestures that appear to be very aggressive, and such things as forehead-wrinkling and teeth-baring are sometimes thought of as ‘fierce’ signals because of this. But in fact they are fear signs, the face providing an early warning signal that fear is very much present, despite the persistence of intimidating gestures by the rest of the body. It is still, of course, a threatening face and cannot be treated smugly. If full fear were being expressed, the face-pulling would be abandoned and the opponent would be retreating.