Aggression as an Adaptive Response

Evolutionary explanations of aggression

Infidelity & jealousyExplanations of group display in

humansWar & sporting events

Evolutionary explanations of human aggression

• The adaptive and functional benefits of aggressive behaviour must outweigh the possible costs. (Buss & Duntley 2006)

• Status conflicts and access to mates.

• Indirect – gossip, rumours, ostracising people from group.

Aggression in males

• Primary motivator is acquisition of status.• In the EEA, good hunters accrued resources

and skilled fighters could ward off rivals = ATTRACTIVE TO FEMALES.

Why would this

be so?

• Daly & Wilson (1985)- murders in Detroit in 1972

• The motive behind most of the conflicts was status.

• Victims and offenders were unemployed and unmarried young men

• LOW STATUS AND WITHOUT A MATE

So nothing to lose from fighting and

potentially, everything to gain…

Sexual Jealousy and Infidelity in Males

MALE ON MALE AGGRESSION•Daly & Wilson (1985) – 58 / 214 cases of murder motivated by sexual jealousy.•Confidence in paternity and warning to potential rivals

MALE ON CHILD AGGRESSION• Link to parental investment• Males reluctant to expend energy and resources in raising offspring of another male.• BUT refer to bad dad / good step-dad study…

MALE ON FEMALE AGGRESSION• Designed to deter the female from indulging in behaviour not in the male’s interest. • Miller (1980) – 55% battered wives cited jealousy as reason for husband’s behaviour.•Often unfounded, based only on suspicion and fear.

Young (1978)

• Asked students to describe their likely reactions to a jealousy inducing scenario

• Men – respond angrily, become drunk, threaten their rival.

• Women – cry, pretend not to care, try to increase own attractiveness to regain male attention.

Aggression in females

• For females, the costs of aggressive behaviour exceed the benefits.

• The mothers’ presence is more critical to offspring survival than the father’s. (Campbell 2002)

• High status, dominant, aggressive females not preferred as mates so no adaptive value in overt aggression.

• BUT low risk, indirect strategies such as gossiping, name calling and ostracising to decrease attractiveness of competing females developed to reduce risk of physical injury.

• Griskevicius et al (2009) gave students scenario of person of same sex spilling a drink on them at a party and not apologising .

• Majority of men would respond with direct aggression (eg, pushing the other man)

• Only a quarter of women would do so, most women most likely to walk away.

Women most likely to use direct aggression when competing for resources that will aid their survival

Explanations of Group Display in Humans

1.WAR• Men only willing to fight as part of coalition if confident of victory.• In Yanomamo of Amazon rainforest, frequent fighting between villages over abduction of women. (Chagnon 1968)• Success in battle > high status• Successful warriors had more wives and children• Young men who had not killed were rarely married.

• Pinker (1997) – In WW2, Germans raped women in concentration camps.

• More than 20,000 Muslim girls and women raped as part of genocide programme in Bosnia.

• Aim was to make the women pregnant and raise the children as Serbs, or terrorise them into fleeing the land (Allen 1996)

• Evolutionary theory can explain tribal warfare where casualties are few and rewards, great.

• But in recent human history, prolonged warfare results in significant losses on both sides.

• Wrangham (1999) – military incompetence is result of adaptive self-deception.

• Positive illusions about winning will improve cohesion and co-operation and may bluff the opposition BUT may also lead to inaccurate assessment of own and opponents’ abilities.

• http://www.youtube.com/watch?v=tdMCAV6Yd0Y&NR=1

• Ritualised form of aggression – benefits of success available to competitors with reduced risk of physical harm / death.

• Winning team hold high status , team members seen as desirable mates.

Explanations of Group Display in Humans

2. SPORTS EVENTS

• In certain games (eg, rugby union) a level of aggression is sanctioned but some players still break the rules.

• Maxwell & Viscek (2009) – questioned 144 rugby union players about their aggression in the game.

• Those high in professionalism placed more emphasis on winning and were more likely to use unsanctioned aggression.

• Cheating (and not getting caught) is adaptive.

What’s wrong with self report as a method ?

• Victory in matches also brings status to fans• Cialdini et al (1976) ‘basking in reflected

glory’ – after a university football team had performed well, students more likely to wear university scarves and sweaters.

• Marsh (1978) – football hooliganism is human equivalent of ‘ceremonial conflict’ in animals.

• Exclusively male, ritualised symbolic aggression restrained by desire to minimise harm and death.

• Intention is to humiliate opposition and secure submission.

Football hooliganism

Is this a realistic interpretation though?

Research instances of football hooliganism to criticise this

view.