The Ethological Explanation Flashcards
What is the ethological explanation?
Seeks to understand the innate and adaptive value of behaviour in animals by studying them in their natural environments
What is a sign stimulus?
A specific stimulus which triggers the innate releasing mechanism
What is an innate releasing mechanism (IRM)?
A neural network which is activated by an external stimulus (sign stimulus) which in turn triggers a fixed action pattern of behaviours associated with that stimulus
What is a fixed action pattern (FAP)?
A sequence of stereotyped, pre-programmed behaviours triggered by an innate releasing mechanism (IRM) and which do not require learning
What is ritualistic aggression?
Aggressiveness being ritualised (series of behaviours being carried out in a set order) in the form of threat displays. E.G teeth baring and claw displaying
What is evidence for fixed action patterns?
Tinbergen (1951)- presence of another male stickleback with sight stimulus of a red underbelly activated IRM with caused male to release FAP of aggression towards other male
What is the Strength of the ethological explanation in aggression?
Benefits of ritualised aggression
In non-human species, ritualised aggression prevents conflicts escalating into potentially dangerous physical aggression. Evidence has shown that this advantage is evident in human cultures. Chagnon (1992)- studies of the Yanomamo people of South America found that chest pounding and club fighting contests can settle a conflict so even in highly violent cultures rituals can reduce actual aggression and prevent injury or death.
Counter-Goodall (2010) studied male chimps and found that from one community chimps systematically slaughtered all the members of another group. They did this in a coordinated and premeditated fashion. The violence continued like this despite the fact that victims were offering signals of appeasement and defencelessness.
These signals didn’t inhibit the aggressive behaviour of the attackers as predicted by the ethological explanation.
What are the 3 limitations of the ecological explanation in aggression?
Cannot explain cultural differences in aggression-
Evidence that aggressive behaviour is more common in some cultures than in others.
Nisbett (1993) found there was a north-south divide in homicide rates in the USA. Killings are more common amongst white males in the southern states than in the northern states > this difference in homicide rates was caused by a
‘culture of honour’ - the response to impulsive aggression was a learned social norm.
Nisbett et al. (1996) further supported this and found that when white males from the south were insulted in a research situation, they were more likely than northern white males to become aggressive.
It is difficult for ethological theory, with its view of aggression as instinctive, to explain how culture can override innate influences.
FAPs not that fixed- Fixed action patterns are more flexible than implied by the term fixed.
Hunt (1973) has argued the role of environmental factors has been underestimated - e.g. an aggressive FAP is made up of several behaviours in a series. The duration of each behaviour varies from one individual to another and even in the same individual from one encounter to another suggesting that they are modifiable by experience.
The term ‘fixed action pattern’ has been replaced by the term ‘modal behaviour pattern’ within ethology to reflect the fact that these are not simply innate and can be modified by experience.
Uniustified generalisation to humans- Lorenz did not study higher mammals such as primates, nor did other ethologists study aggression in humans. Yet generalisations about aggressive behaviour from animals to human are made. Lorenz also drew conclusions from the behaviour of individual animals to the behaviour of entire countries and states.
