Evolutionary Explanations of Human Aggression

Explanation

• Aggression is a strategy - effective for solving a number of adaptive problems (gaining resources, intimidating male rivals)
• Solving these problems = increased chances of survival and reproduction
• Aggression is increased when resources such as territory, food and mates are scarce (poor).

Sexual Competition

• Competition between males to have access to females through aggression (physical contact)
• Aggression used successfully = Passing genes to offspring (increased reproduction)
• Development of a tendency for males to be more aggressive.

Jealousy

• Sexual Jealousy - primary cause of violence against women and the reason for aggression amongst males.
• Paternal uncertainty - men at the risk of cuckoldry (raising a child who is not his own)
• Thought of investing resources in offspring that are not his own.

Mate Retention & Violence

• Strategies include:
• Restricting their partners' autonomy (taking away their freedom/not having independence)
• Negative inducements (threatening their partners) in the form of violence

Sexual Jealousy & Extreme Violence

• Male sexual jealousy - single most common motivation for the killings of domestic partners.
• Research = sexual jealousy accounted for 17% of all cases of murder in the UK
• 92% male-male murders & 8% female-female murders.

EVALUATIONS - Research Support

• Shackelford et al. used a survey to test mate retention strategies. Used 461 men and 560 women
• Findings : Clear relationship between sexual jealousy, mate retention strategies by males and violence towards man.

EVALUATIONS - Practical Applications

• Particular tactics of mate retention could be an early indicator of violence against the female partner.
• Potentially be used to alert friends and family members to danger signs that could lead to violence in relationships.
• Help can be offered before violence actually happens.

EVALUATIONS-Physiological Basis for Jealousy

• Male sexual jealousy is linked to aggression - supported by research
• Neural response to sexual infidelity and emotional jealousy were different when showed imagined scenes.
• Men showed greater activation in the amygdala and hypothalamus than women.

EVALUATIONS-Physiological Basis for Jealousy

• Male sexual jealousy is linked to aggression - supported by research
• Neural response to sexual infidelity and emotional jealousy were different when showed imagined scenes.
• Men showed greater activation in the amygdala and hypothalamus than women.

EVALUATIONS - criticism

• Edlund and Sagarin claim that our understanding of the relationship between sexual jealousy and aggression is limited.
• Research does not tell the degree of perceived infidelity is important.

Infidelity

• Voluntary sexual relations between an individual who is married and someone who is not.
• Detection or suspicion of infidelity is a key predictor of partner violence.
• Men are more likely to engage in extra-marital affairs than women.

Sexual Coercion

• Partner rape
• Sexual assault of a female by her male partner was directly linked with the perceived risk of her infidelity.
• Victims of partner rape were more likely to have reported engaging in extra-marital sex than women who had not been raped by their male partner.

Violence towards pregnant partners

• Pregnant with another male = violence directed to terminate the pregnancy
• To eliminate the potential offspring of a rival
• Free to bear offspring of another male.

UXOROCIDE

• Wife killing
• Some men are more prone to using violence or the threat of violence
• Death of the partner from physical violence may be an unintended outcome (?)

EVALUATIONS - Research Support

• Sexual coercion among males, but not along females.
• Since males are at the risk of cuckoldry.
• Researcher found - men who have raped their partner were more likely to have experienced cuckoldry.

EVALUATIONS- Supporting evidence

• Research findings : women abused while pregnant were more likely to be carrying the child of a man other than her current mate.
• Another research finding : Men usually aim towards their partners abdomen to increase the probability of aborting the foetus.

EVALUATIONS- limitations

• Cannot account for why different males when faced with partner's infidelity respond in different way.s
• Aggressive mate retention strategies, murder, get drunk, do drugs etc.