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 visual stimulus which triggers the innate releasing mechanism.
What is an innate releasing mechanism (IRM)?
A physiological process or neural network which is activated by a 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 and does not require learning.
State the six main features of a FAP, according to Lea (1984).
Universal, stereotyped, innate, ballistic, specific triggers and single purpose.
Describe a study that shows evidence for FAPs
Tinbergen (1951)
During the mating season, male stickleback fish develop a red spot on their underbelly - sign stimulus. Tinbergen presented sticklebacks with a series of wooden models of different shapes, with and without a red underbelly.
He found that regardless of the shape, if the model had no red spot there was no aggression, even if the model looked realistically like a stickleback, and if there was a red spot, the fish would always attack it. FAPSs were unchanging from one encounter to another and once triggered, it always completed its course.
According to the ethological explanation, why is aggression adaptive?
If an animal is aggressive, it forces the “defeated animal” to establish territory elsewhere and so reduces competition for food and the possibility of starvation
What is ritualistic aggression?
Behaviours carried out in a set order in the form of ritualistic signalling and threat displays (e.g. gorilla beating chest, wolf baring teeth, cat displaying claws).
What is an appeasement display?
Aggressive confrontations end with ritual appeasement displays which indicate acceptance of defeat and inhibit further aggression behaviour in the victor, preventing any damage to the loser.
Why is ritualistic aggression adaptive?
It prevents an animal being damaged and potentially killed which facilitates the survival of the wider species.
1 Strength for the ethological explanation (1 COUNTER)
Benefits of ritualised aggression:
It prevents conflict escalating into potentially dangerous physical aggression. Changnan (1992) extensively studied the Yanomamo people of South America where a willingness to use violence was indesirable. Their culture provides a regulated system to control there violence expressions. Changnan found conflict is regulated through chest pounding and club fighting and the people can remain on peaceful terms afterwards, preventing injury or death
HOWEVER,
Goodall (2010) studied male chimps and found one community of chimps systematically slaughtered members of another group even though victims were showing signs of appeasement. This challenges the notion that ritualised aggression is a harmless ritual.
2 Limitations for the ethological explanation for aggression
Unable to explain cultural differences:
Nisbett (1993) found there was a North-South divide in homicide rates in the USA. Killings more common amongst white males in the Southern states. Caused by a “culture of honour” where response to reactive aggression is a learnt 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 are more flexible than implied by the term “fixed”
Hunt (1973) argued that the role of environmental factors have been underestimated. The duration of each behaviour varies from one individual to another and even in the same individual from one encounter to another. Suggests they are modifiable by experienced and better explained as “modal behaviour patterns”.
