Ethological explanations of aggression

Question 1

How is aggression adaptive

Answer 1

Beneficial to survival as defeated animal has to find other territory
=species have to spread out/find resources in new place
= - competition pressure/possibility of starvation

-Also to establish dominance hierarchies (e.g male chimpanzees)

Question 2

Study of humans establishing dominance

Answer 2

Pettit et al (1988) Studied young children and observed how aggression made dominance hierarchies

=Adaptive as dominance brings benefits e.g access to resources

Question 3

Lorenz theory of ritualistic aggression

Answer 3

Intra-species fights ended in little damage
-Aggression was prolonged ritualistic signalling (e.g flashing teeth)
-Ended in ritual appeasement displays

Question 4

What are ritual appeasement displays

Answer 4

Submission- indicate acceptance of defeat/prevent further aggressive behaviour

Question 5

Example of ritual appeasement displays

Answer 5

Wolf exposes its neck to victor

Question 6

Why does intra-species aggression result in little damage

Answer 6

If every aggressive encounter ended with death it could threaten the existence of the species

Question 7

What is an innate releasing mechanism (IRM)

Answer 7

Inbuilt physiological process or structure

Question 8

What is an Fixed action pattern (FAP)

Answer 8

Specific sequence of behaviour released when IRM triggered by environmental stimulus

Question 9

What are the six main features of FAPS according to Stephen Lea

Answer 9

Stereotyped
Universal
Unaffected fed by learning
Ballistic
Single-purpose
Response

Question 10

What does FAPS being ballistic mean

Answer 10

One behaviour triggered it follows inevitable course and can’t alter

Question 11

What does FAPS being stereotyped mean

Answer 11

Relatively unchanging

Question 12

What does FAPS being single purpose mean

Answer 12

Only occurs in a specific situation

Question 13

Tinbergen’s research into FAPS procedure

Answer 13

Presented sticklebacks with a series of wooden models of different shapes

Question 14

What is the sign stimulus for male sticklebacks in mating season

Answer 14

Red spot on underbelly= aggressive FAP

Question 15

Findings of Tinbergen’s research

Answer 15

-Regardless of shape males would attack model with red dot

-No red dot= no attack

-FAP always ran it’s course without further stimulus

Question 16

Who researched FAPS in male sticklebacks

Answer 16

Niko Tinbergen (1951)

Question 17

Weakness of ethological explanation

Answer 17

Same species aggression not always ritualistic
-e.g Goodall 4 year war= male chimps killed each other even when appeasement signals

This challenges the ethological view that same-species aggression has evolved into self-limiting/harmless ritual

Question 18

Weakness 2

Answer 18

Lorenz’s original View of FAPS outdated
-e.g said innate/unchanging but Morton Hunt found influenced environment/experience so more like “model behaviour pattern”

=FAPS much more flexible than Lorenz thought