Ethological explanation

• What is ethology?

  An explanation that seeks to understand the innate behaviour of animals by studying them in their natural environment
• What are the adaptive functions of aggression?

  The main function of aggression is adaptive, aggression is beneficial to survival because a 'defeated' animal is rarely killed but forced to establish territory elsewhere. So members of species spread out over a wider area reducing competition pressure and the possibility of starvation. Male chimpanzees use aggression to climb their troops social hierarchy, dominance gives them special status (mating rights).

  Also happens in humans Pettit (1988), groups of young children and observed how aggression played an important role in development of dominant hierarchies This is adaptive- naturally selected because dominance brings benefits such as access to resources (food/mates)
• What is ritualistic aggression?

  A ritual is a series of behaviours carried out in a set order, Lorenz (1966) observed fights between animals of the same species produced little actual physical damage. Most aggressive encounters consisted of a prolonged period of ritualistic signalling (claws, teeth). Lorenz pointed out that intra-species aggressive confrontations end with ritual appeasement displays, these indicate acceptance of defeat and inhibit further aggressive behaviour in the victor, preventing any further damage to the loser. This is adaptive because if every aggressive encounter ended with death of one of the combatants, that could threaten the existence of the species.
• What is innate releasing mechanisms and fixed action patterns?

  An IRM is an inbuilt physiological process or structure, for instance a network of neurons in the brain.

  An environmental stimulus triggers the IRM which then 'releases' a specific sequence of behaviours.

  This behavioural sequence is called a fixed action pattern (FAP), according to Lea (1984), FAP's have six main features:

  -stereotyped, or relatively unchanging sequences

  -universal

  -unaffected by learning

  -ballistic once behaviour is triggered

  -single purpose

  -releasers
• What was Tinbergen's research into sticklebacks?

  Procedure:

  Male sticklebacks are highly territorial during spring mating season, when they develop a red spot on their underbelly, if another male enters their territory a sequence of highly-stereotyped aggressive behaviours is initiated (FAP) the sign stimulus that triggers the innate releasing mechanisms is the sight of the red spot. Tinbergen (1951) presented sticklebacks with a series of wooden models of different shapes.

  Findings:

  Regardless of the shape, if the model had a red spot, the male stickleback would aggressively display and even attack. Tinbergen found that aggressive FAP's were unchanging from one encounter to another, once triggered the FAP always ran its course to completion without any further stimulus
• AO3- Supporting evidence

  E- Brunner (1993) showed that one gene (MAOA-L) is closely associated with aggressive behaviour in humans. Twin and adoption studies showed a significant genetic component to aggression in humans. Wilson and Daly (1996) saw aggression as an adaptive behaviour and is genetically based, research is pointing towards an innate basis to aggressive behaviour.

  E/L- Research support related to genetics and evolution, suggesting the ethological approach is correct in claiming that aggression is genetically determined, heritable and adaptive. Backing up the ethological approach in explaining human aggression= more relaible
• AO3- Cant extrapolate to other cultures across the world

  E- Nisbett (1993) found one type of homicide was more common amongst white men in the southern US than in northern states. Reactive aggression is a response to threats from someone else. The difference was caused by a 'culture of honour' in the southern US- less prevalent in the north, which is why reactive aggression homicide rates are lower there. This kind of aggressive behaviour comes from learned social norms rather than being instinctive

  E/L- Culture can override innate predispositions, which ethological theory cant explain. Aggressive behaviours differ from one culture to another, reducing reliability as cant be generalised universally across cultures undermining
• AO3- Aggression against members of the same species is not just ritualistic

  E- Goodall (2010) observed a 4-year-war where male chimps from one community killed all the members of another group in a systematic way. On some occasions, a victim would be held down by rival chimps while others hit and attack, the violence would continue even though the victims offered appeasement signals. These signals didnt inhibit the aggressive behaviour of the attackers as predicted by ethological

  E/L- This challenges the ethological view that the same-species aggression evolved into a self-limiting and relatively harmless ritual, aggression against members of the same species is not just ritualistic. Undermining research as it challenges the reliability
• AO3- Lorenz's original view of FAP's is outdated

  E- Hunt (1973) pointed out FAP's are greatly influenced by environmental factors and learning experiences. EG/ an aggressive FAP is typically made up of several behaviours in a series. The duration of each behaviour varies from one individual to another, even in the same individual from one encounter to another. They are modifiable by experience, its now referred to as 'modal behaviour patterns'

  E/L- Patterns of aggressive behaviour are much more flexible than Lorenz thought, especially in humans. Need to take into account alternative explanations to get a full understanding of why aggression occurs as it may be outdated need to be cautious