In his early work, Freud thought that frustration was one factor that led to aggression. Later, Freud expanded this to say that aggression was part of a death instinct. This indicates that aggression is inborn. Thus aggression was seen not only as a way to deal with some frustrating obstacle but also as a need of its own.
Although most clinicians avoid this instinctive view, ethnologists -biologists and psychologists who study animal behavior - seem to agree with it. Ethnologists see aggression as an instinct in both animals and humans that needs to be expressed. In their early work, ethnologists noted a major difference between the aggression of animals and the aggression of humans. Animals seem to have inborn mechanisms to control their aggression, but humans do not. Unfortunately, later work seems to indicate that animals are no better in controlling their aggression than we are.
Within their own species, animals fight for food, mates, nesting areas and to protect the young. Since the most successful aggressor will get the most females, they will procreate more. In addition, these aggressive instincts tend to space the animals' territories, so there is enough food for all.
According to ethnologist Konrad Lorenz in the 1960s, the fruits of their intra-species aggression can be enjoyed, because animals have inborn inhibitions to keep them from destroying members of their own species. The threatening displays of their ritualistic aggressive behavior usually avoid most of the actual combat. When they do fight, it is a stylized method of combat that only rarely results in serious injury. The loser can display signs of submission that inhibit further aggression from the victor. For example, if a wolf lies down and exposes his throat, the victor will stop the attack.
According to Lorenz, this is in sharp contrast to what happens in humans. Humans have developed weapons that can deal out death at great distances without even coming into contact with the victims. Even if we did have similar inhibitions, the separation of the aggressor and victim would nullify their effects on aggressive instincts.
However, more recent data have shown that not all species have innate inhibiting signals - and these signals are not effective in all foes. Acts of murder, rape and infanticide are much more frequent than was hypothesized in the 1960s. In fact, there are even "border wars" among different groups of chimpanzees. The best-observed case was in Tanzania, Africa. There was a gang of five male chimpanzees that defended their territory against any intruding male. If two or more strange chimps entered their domain, the encounter would be noisy but not deadly. It was much different, if the intruder was alone. Several members of the gang would hold the intruder's limbs, while a remaining member of the gang would beat the intruder to death. Another tact was for a few of the gang members to drag the intruder over the rocks to kill him. In another border dispute in the 1970s, a group of 15 chimps demolished another nearby group by killing them off - one lone male at a time.
Female chimps are as aggressive as the males. The only reason they do not kill as often is that their teeth are not as long or sharp as those of the males.
These observations and others changed our view of animal aggression. In 1983, sociobiologist E. O. Wilson went so far as to state:
"If you calculate the number of murders per individual animal per hour of observation, you realize that the murder rate is higher than for human beings, even taking into account our wars."
According to some experts, beside the similar frequency of aggression, humans and animals have similar inhibitions related to violence. Animals use markers - strong odors and loud calls - that permit one side to withdraw before aggressive behavior can occur. Animals also use social responses that are not compatible with aggression. Mutual grooming - softly touching or fingering the body of other animals - is one of these responses.
The most important factor to inhibit aggression is familiarity. Mutual greeting rituals - like sniffing each other - make them familiar with each other. It helps them to tell the difference between strangers and group members.
In humans there is only weak evidence that our aggression is instinctive. Now almost all of the evidence indicates that aggression in humans is alearned behavior. As children, we learn form others around us. Models - both in real life and the media - frequently demonstrate that the only way to deal with any disagreement is aggression. If the child imitates this aggression - and is rewarded by obtaining goals that were previously denied - that child is well on the way of making a habit of aggression.
Rather than aggression, other methods can be used or taught to help people dealing with disagreements. Open communication, assertiveness and compromise techniques can be demonstrated and taught to our children - and adults too. Becoming familiar with people from different groups will help us see them as human beings - in contrast to viewing them a sub-human or non-human. (Notice how our view of Russians has changed now that we know some individuals better.)
If aggression is learned, it can also be unlearned.
* Adapted from Atkinson, Atkinson, Smith & Bem's Introduction to Psychology, Harcourt Brace Jovanovich Publishers, 1990, pages 426-427.