Ethological & evolutionary explanation

Slide 1

• Ethology is the study of animal behaviour. The study of animals can help us understand human aggression in 3 ways:
• It helps define aggression & looks at how it occurs with other behaviours such as reproduction & threat.
• Looking at animals in their natural setting, means we can understand the way it has helped the evolutionary process. This is more difficult with humans in the modern-day habitat.
• When animal behaviour is studied in laboratory settings, the conditions can be highly controlled & this is not possible to the same extent with human participants.
• Innate releasing mechanisms (IRMs) - Lorenz published a book on aggression & in it he described the innate drive of aggression. Lorenz likened aggression to other instinctive drives such as that for food. He suggested that aggression was 'a need' that had to be satisfied & that animals had a specific neural circuitry inside the brain(IRM) which monitored the drive.
• Fixed action pattern(FAP) - When the IRM is triggered by an environmental stimulus, a specific sequence of behaviour is released. This sequence is called a FAP because it is universal & invariant across any one species. These behaviours are unaffected by learning & are 'ballistic', i.e: once triggered, the behaviour follows a set course & is not subject to alterations. Each individual behaviour is specific to a particular situation & is a response to a particular sign stimulus.

Slide 2

• Research
• Tinberger(1952) explored IRMs & FAPs in sticklebacks. The FAP starts with the nesting behaviour in spring. Establishing a territory around a nest is important to the stickleback so any other male sticklebacks that encroach on the territory are met with aggressive attacks. However, female sticklebacks are encouraged to stay so that they can lay eggs in the pre-pared nests. This shows that the behaviour is invariant i.e: all males do it & it is a strong argument for the behaviour being innate. It is argued that these fixed action patterns are adaptive because they increase evolutionary fitness.
• Evaluation
• -A key point of the ethological theory is that the behaviour is universal to the species. This is clearly not the case for humans as even within the same situation some will react aggressively, others will not. This makes the presence of an innate mechanism & a fixed action pattern unlikely.
• -Generalising from animals research to human aggression is problematic.

Slide 3

• Evolutionary explanation - the premise that aggression has an important function both in terms of individual survival & reproductive success. It can help an individual to fight for resources if they're in short supply. It might also be, in the case of male aggression, that they appear more attractive to females as they would appear strong; be able to protect their offspring.
• Evaluation
• -This explanation seems to suggest that it is excusable & beyond a person's control. This has important consequences within the legal system & within society generally. This makes the research socially sensitive.