ethological explanation

• main function

  adaptive - allows individuals to become dominant over others - access to resources
• Lorenz


  fights rarely result in physical damage - most aggressive encounters consist of ritual signals and signs - allow individuals to assess relative strength without excess harm being caused - damaging for species as a whole
• Tinbergen 


  sign stimulus (environment) - innate releasing mechanisms (motor circuits) - fixed action pattern (stereotypical behaviours)
• Male stickleback fish

  red spot on underbelly in mating season - another male enters territory see red spot (sign stimulus) causes innate releasing mechanisms to initiate sequence of stereotyped aggressive behaviours (FAPs) to reduce chance of eggs laid in his territory being fertilised by another male
• Lea - FAPs - 6 main features

  stereotyped (always occur in same way) - universal (found in every member of species) - unaffected by learning (same for every individual) - ballistic (once behaviour is triggered it can't be stopped) - single purpose ( only occur in specific situation and not in any other) - specific triggers (each FAP has a specific trigger)
• ETHOLOGICAL EVALUATION - Tinbergen


  found when male sticklebacks presented with series of models, they would attack it in the same way regardless of shape (only if it had a red dot) wouldn't with no dot even if it was a realistic model - supports members of same species have IRM that's triggered by sign stimulus
• ETHOLOGICAL EVALUATION - may lack generalisability to humans

  Lorenz and Tinbergen tried to generalise FAPs in animals to humans, failed to acknowledge flexibility of human behaviour in modern times - ever changing environment meant ability to adapt behaviour proved more effective than FAPs - may be limited to certain species
• ETHOLOGICAL EVALUATION - ignores role of culture in human aggression

  Nisbett - found north south divide in USA for homicide rates - much more common in white males in southern states than northern states - concluded difference caused by culture of honour as a learned social norm - against view that aggression is universal
• ETHOLOGICAL EVALUATION - 'fixed' been criticised

  Hunt - Lorenz underestimated role of environment in developing patterns and learning and experience interacts with innate factors to produce subtle variations in behaviour - members of same species shown to differ in duration of behaviour and in same animal in different encounters - should be replaced with 'behaviour pattern'
• ETHOLOGICAL EVALUATION - FAPs avoid physical harm criticised

  male lions kill off cubs of other males and male chimpanzees routinely kill members of another group - questions that much of animal aggression is ritualistic rather than real