Psychology Evolutionary Theory of Aggression

Evolutionary psychologists believe that aggression is linked through genes and has been maintained biologically as people have adapted to the changing physical and social demands of the environment. In the past, males that found other mates desirable found it necessary to compete with other males. The most successful male was the most aggressive. This aggressive behaviour made sure that the fittest males survived and were more successful in securing mates and passing on their genetic fitness to their offspring. In terms of evolutionary explanations, this is known as sexual selection and has led to the development genetically for males to behave aggressively with other males.
Evolutionary explanations also state that males would not be expected to fight with females as this would ruin their chances of sexual intercourse with other willing females. This is because females believe that those males that have this particular behaviour would be too dangerous for not only them but also any future children.
On the other hand, Hilton Harris and Rice stated that females are equally as aggressive as males as they are known to be a lot more choosy in order to find the right partner. However, evolutionary explanations of male aggression towards females can be explained through jealousy and infidelity.
Jealousy is defined as an emotional state that is caused by a perceived threat to a relationship or position. Buss states it motivates behaviours and is a reaction related to fear and rage. Evolutionary psychologists believe that there are differences between men and women in relation to what triggers jealousy.
This is where the factor of infidelity comes into place, as the trigger in males is the fear of a partner’s sexual infidelity, as this will lead to uncertainty in whether or not the child is actually his. Therefore, according to Archer male aggression can be viewed as sexual jealousy and possessiveness which comes from the whole concept of the uncertainty of the male. As when a male is not sure if his child is actually his, he will become jealous which will therefore make him aggressive in order to find out the child's father.
On the other hand, this whole idea of paternal uncertainty does not happen with females as they know the child has come from them. However, the jealousy from a woman would come from her partner beginning to spend a lot of time on another relationship or on another female, could lead to jeopardizing her and her child's survival. Looy also states that jealousy in women is triggered by emotional connection of the presence of younger attractive women, which would lead to aggressive behaviour to the partner and the other woman.
Strengths of the evolutionary explanation would be that the concept of sexual selection and survival of the fittest where males compete aggressively against each other and the female chooses the strongest male, makes clear sense and has therefore got face validity. Buss found that displays of aggression in human reproductive behaviour are innate and are determined by our genes as his research found that human aggressive behaviour is similar across culture and is not influenced by social norms.
However, the first problem with the evolutionary explanation is that it is a post hoc theory. As it explains aggressive behaviour after it has happened rather than making predictions of what is going to happen and then testing it. Evolutionary explanations are also deterministic, as it implies that we are slaves to inborn aggressive instincts and are unable to exercise free will.
Another weakness of this explanation is the fact that it is reductionist as it fails to offer a complete explanation of displays of aggression in human reproductive behaviour, it limits it to simple genetic pressures (nature), which makes the theories easier to understand, but means they miss out on some details, such as the role of social learning in shaping our reproductive behaviour (nurture).