Ethological Explanation of Aggression: Innate Releasing Mechanisms and Fixed Action Patterns

Question 1

what are innate releasing mechanisms?

Answer 1

• an inbuilt physiological process or structure

Question 2

what is an example of innate releasing mechanisms?

Answer 2

• a network of neurons in the brain

Question 3

what triggers innate releasing mechanisms?

Answer 3

• an environmental stimulus (e.g. certain facial expressions) trigger the innate releasing mechanisms
• this then releases a specific sequence of behaviours

Question 4

what are fixed action patterns?

Answer 4

• specific sequence of behaviours released by innate releasing mechanisms

Question 5

who came up with the six main features of fixed action patterns?

Answer 5

Stephen Lea

Question 6

what are the six main features of FAPs?

Answer 6

• stereotyped, relatively unchanging sequences of behaviours
• universal, as the same behaviour is found on every individual of a species
• unaffected by learning, the same for every individual regardless of experience
• ballistic = once the behaviour is triggered it follows an inevitable course and cannot be altered before it is completed
• single-purpose, behaviour only occurs in a specific situation and not in any other
• response is an identifiable specific sign stimulus (involves communication between members of the same species = known as a releaser)

Question 7

what is the procedure of Tinbergen’s research?

Answer 7

• male sticklebacks are highly territorial during the spring mating season, where they develop a red spot on their underbelly
• if another male enters their territory, a sequence of highly-sterotyped aggressive behaviour is initiated (FAP)
• sign stimulus = sight of the red spot so triggers the innate releasing mechanism
• Tinbergen presented sticklebacks with a series of wooden model of different shapes

Question 8

what are the finding of Tinbergen’s research?

Answer 8

• regardless of shape, if the model has a red spot the male stickleback would aggressively display and even attack it
• no red spot = no aggression, even if the model looked realistically like a stickleback
• Tinbergen found that aggressive FAPs were unchanging from one encounter to another
• once triggered the FAP always ran its course to completion without any further stimulus