Ethological explanations of aggression Flashcards
Ethology is the study of animal behaviour in natural settings. Ethological explanations of aggression propose that aggression is INNATE and ADAPTIVE
This is because an undefeated animal is more likely to SURVIVE, and aggressive animals are likely to become DOMINANT in their hierarchy.
For example, male chimpanzees use aggression to achieve status at the top of their troop hierarchy
benefits including access to food and female mates
Ritualistic aggression
Most intra-species aggression actually involves very little physical fighting and instead consists of ritualised signalling of aggression.
These SIGNALS intend to intimate an opponent without actually engaging in physical contact
The opposing rival can then make a decision as to whether to engage in fighting or submit and leave.
Ritualistic aggression can also indicate defeat and appeasement.
For example defeated wolves will expose their necks to the victor to indicate its vulnerability to a single bite in the jugular vein.
Animals possess innate behaviours called FIXED ACTION PATTERNS (FAP’s) which are produced by
a neural mechanism known as an INNATE RELEASING MECHANISM (IRM) in response to specific ‘sign stimulus’.
These ‘signs’ can be what a rival animal looks like
and are usually connected to the internal state of the animal such as its sex drive.
Stereotyped
unchanging sequence of aggression
universal
same behaviour found in every species model
independent of individual experience
behaviour is innate and not learned
ballistic
once triggered the FAP behaviour cannot be stopped and is automatic
specific triggers
certain sign stimulus activates behaviour
supporting evidence for the benefits of ritualistic aggression as it prevents conflicts escalating into dangerous physical aggression
Chagnon
Hoebel
In the Yanomamo people of South America chest pounding and club fighting settles conflicts before more extreme forms of aggression develop
In Inuit Eskimos song duels are used to settle grudges and disputes
rituals have the effect of reducing actual aggression and preventing injury and death, increaing the validity of ethological explanations
contradictory evidence suggesting animals engage in killing their own species
Goodall
study on chimpanzees in Tanzania, male chimps from one community set about systematically slaughtering all members of another group. These attacks appeared to be co-ordinated and premeditated, and one example saw a male chimp being held down and systematically hit and bitten during a 20 minute attack. These attacks continued despite signals of appeasement and defencelessness which did not inhibit the aggression
doubt over the claim most animal aggression is ritualistic rather than real, reduces the validity
fixed action patterns may not be innate behaviour
Environmental factors such as learning and experience can influence aggressive behaviour patterns in animals. The term ‘fixed action pattern’ has now been replaced with ‘behaviour pattern’ indicating that there are differences within the same species regarding the aggressive behaviour displayed.
reduces the validity, contradicts the idea FAPs are indistinctive and universal