Aggression

• Ethological explanations


  The innate behaviour of animals or humans by studying their natural environments
• Adaptive functions of aggression

  • Beneficial to survival as the defeated animal is rarely killed, rather forced to establish territory elsewhere
  • To establish dominance hierarchies
• Dominance hierarchies in chimpanzees and humans

  • Pettit et al (1988) studied playgroups of children and observed how aggression played an important role in the development of some children's dominance over others
• Ritualistic aggression


  • Aggression presented in rituals (showing claws, growling, hissing, showing teeth) and rarely progressed to actual violence
  • Ritual appeasement displays to stop aggression - a wolf will expose its neck to the winner of the fight, purposely making itself vulnerable
• Innate releasing mechanism (IRM)

  A physiological process or structure (e.g. a network of neurons). An environmental stimulus triggers the IRM that releases specific behaviours
• Fixed action pattern (FAP)


  The behavioural sequence released by an IRM
• Features of fixed action patterns

  • Stereotyped - unchanging sequences of behaviours
  • Universal - the same behaviour is found in all individuals in a species
  • Unaffected by learning - same for all individuals, regardless of experience
  • Ballistic - once the behaviour begins, there is no interruption or alteration
• Ritualistic aggression


  Aggression presented in rituals (showing claws, growling, hissing, showing teeth) and rarely progressed to actual violence
• Ritual appeasement displays


  Behaviours to stop aggression, e.g. a wolf exposing its neck to the winner of a fight, purposely making itself vulnerable
• Innate releasing mechanism (IRM)

  A physiological process or structure that triggers specific behaviours when an environmental stimulus is present
• Features of FAPs


  • Stereotyped - unchanging sequences
  • Universal - same behaviour in all individuals
  • Unaffected by learning - same for all individuals
  • Ballistic - set course until completed
  • Single-purpose - only occurs in certain situations
  • Response to an identifiable specific sign stimulus
• Tinbergen found male fish are highly territorial during mating season, developing a red spot on their underbelly. If a male enters their territory, it triggers their FAP. The sign stimulus is the red spot.
• Researchers used wooden fish with a red spot and the male fish would be violent towards it, regardless of the shape, as the red spot was the sign stimulus.
• The aggressive FAPs were unchanging from each other and would fully run its course until it was over.
• Nisbett (1993) found that there was a North-South divide in the USA for homicide rates, with killing being more common in white males from the south than white males in the North.
• Nisbett concluded that this difference in homicide rates was due to impulsive behaviour being a learned social norm.
• Brunner et al conducted research showing that low-activity of the MAOA gene is closely associated with aggressive behaviour in humans.
• The amygdala within the limbic system has been shown to trigger aggressive behaviours in humans and animals when the threat is perceived.
• Goodall conducted observations of chimpanzees that challenged the view that aggression has evolved into a relatively physically harmless ritual. The chimpanzees were aggressive no matter the signals presented.
• Ethological explanation of aggression

  Aggressive behaviour is an innate feature of humans and animals, studied in their natural environments. Aggression is an adaptive function focused on survival, such as gaining territory, resources and dominance in the social hierarchy.
• Sexual jealousy


  A major factor of male aggression due to paternity uncertainty and the threat of cuckoldry. Men have evolved psychological mechanisms to increase anti-cuckoldry behaviours.
• Mate retention strategies


  Direct guarding - male vigilance over a partner's behaviour

  Negative inducements - threats of dire consequences for infidelity
• Women who reported male retention strategies were twice as likely to have suffered physical violence from their partner.
• Shackelford et al found a strong positive correlation between males' mate retention behaviours and women's report of violence in their relationship.
• Bullying


  Aggressive behaviour to increase one's own chance of survival by promoting their health and creating opportunities for reproduction. Characteristics associated with bullying are attractive to women.
• Rigby's review of anti-bullying interventions found that bullying was still prevalent, suggesting the evolutionary approach of increasing the cost of bullying and rewarding alternative behaviours is more effective.
• Campbell argues that females with offspring are less likely to be physically aggressive because such behaviour would risk their own and their child's survival, leading them to use verbal aggression instead.
• The frustration-aggression hypothesis suggests that anger, hostility and violence are always the outcome when we are prevented from achieving our goals.
• Frustration-aggression hypothesis


  Aggression is a psychological drive that is satisfied through aggressive behaviour, which has a cathartic effect.
• Green found that participants who were insulted gave the strongest shocks, then the interfered group, then the impossible tasks group, all more than the control group.
• Weapons effect


  Aggressive environmental cues, such as the presence of weapons, stimulate aggressive behaviour.
• A meta-analysis found that participants who were provoked but unable to retaliate directly were significantly more likely to aggress against an innocent party.
• Studies have found that participants who vented their anger by hitting a punching bag became more aggressive rather than less.
• Berkowitz's 'the trigger can pull the finger' metaphor has been used in the gun control debate in the United States.
• Social learning theory


  Aggressive behaviour can be learned through both direct and indirect learning, including observing role models and vicarious reinforcement.
• Mediational processes


  Cognitive conditions needed for observational learning: attention, retention, reproduction, motivation.
• Poulin and Boivin found that aggressive boys formed friendships with other aggressive boys, which reinforced their antisocial behaviour.
• When analysing markets, a range of assumptions are made about the rationality of economic agents involved in the transactions
• Imitated the aggressive behaviour themselves
• Social learning theory (SLT) explanation of aggression

  • There is supporting research for it
  • Cannot explain all aggression