Family Violence and Evolution

1
Family Violence and Evolution

• When and why are males violent?
• Keith Morgan
• Liverpool Hope University

2
Acknowledgements

• Although I am interested in this topic I am not
  an expert.
• This would have been impossible without the help
  of
• Karen Downing
• Kate Cassim
• Kerri Nixon
• Satoshi Kanazawa
• John Archer

3
Outline

• What is Human Evolutionary Psychology?
• What is Family Violence?
• Spousal abuse
• New statistics for Merseyside
• Male sexual jealousy
• Conclusion.

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Human Evolutionary Psychology

• HEP from Daly Wilson Using evolution to
  explain human behaviour.
• Humans are animals biological organisms.
• Humans now have been produced by evolution. In
  Environment of Evolutionary Adaptation?
• HEP success Having successful children.
• Or helping to spread your genes.

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Family Violence

• Violence between members of family.
• Parents vs children
• Sibling vs sibling
• Father/mother vs Mother/father
• Grandchild vs grandparent
• Gay and lesbian couples
• Honour violence
• Interpersonal (physical, sexual,psychological),
  stalking and financial abuse now recognised.

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Some Relevant Statistics

• 80 UK IPA of elderly by males.
• Teen violence to parents US white mothers gt40
  most likely to be attacked by 14-17yr sons
• US review of teen studies gt 10 m, 7 f attack
  their parents each year. Mothers more often
  targets.
• gt50 siblings attacked by sibling each year.
  Canada 2 murders are inter siblings. (US 1).
  No sex differences.

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Latest Merseyside Statistics Intimate Partner
Violence

• Focus on IPV clear sex diffs, Feminist HEP
  theories.
• 28 f vs 18 m been targets (BCS 2005).
• 21, 350 reports to Merseyside police in 2005.
• Domestic abuse common, gtoffenders male.
• 635, 000 reports a year in England and Wales.
• In 50 cases, children also get hurt.
• About 100 women killed each year in UK DA.
• About 20 UK violent crime is DA.

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Why Would Men Attack Their Partners?

• Universal problem, but rates do differ.
• Factors like hostile beliefs about f, acceptance
  of aggression against f, beliefs that m are
  dominant, hostility to f predict sexual
  aggression. (Murnen et al 2002).
• Women share that cultures mens attitudes as to
  if and when it is acceptable (correlations can be
  over r.60)
• 86 Egyptian sample, 15-49 yr f, agreed it is OK
  in some circumstances (El-Zanty et al 1995).
• gt50 UK sample, young male, said OK to hit in
  certain circumstances (eg if she nags you!)
• UK teenage females agree (eg if they kiss another
  male).

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Cross-Cultural Differences

• Among non-Western nations, men are more likely to
  inflict violence on women than vice versa (Archer
  2006).
• In the west, women use acts of physical
  aggression to their heterosexual partners more
  frequently than men (Archer 2000).
• Strong negative correlations between womens
  power in a society, compared to mens, and the
  rate of IPV to females (Archer 2006).
• Also seen comparing US states (Straus1994)
• It is also clear that women are attacked by male
  partners commonly across the world.
• Data consistent with both evolutionary and
  feminist view?
• Archer (2006) argues for Social Role Theory.

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Cross-Cultural Differences in Women Attacked by
Male Partners
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Domestic Abuse on Merseyside 600 Consecutive
Cases (2005)
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Different Reproductive Strategies

• M sperm tiny, 180 million per ejaculation.
• M not attached to embryo.
• gt Have lots of sex with many partners, then run.
  (1 possible way to get lots of kids.)
• F egg large, 1-2 eggs per month, 350 in life.
• F embryo depends on F.
• gt Choose carefully, best mate you can.
• BUT...

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Bad News for Males

• F knows a baby is hers.
• F does not show when she is fertile.
• M does not know a baby is his.
• M cannot guard mate for few days.
• gt M very vulnerable to sexual infidelity.
• Wastes resources on unrelated kid (competitor for
  own), not bringing up own kid. Poor reputation.
• gt Evolution of Male Sexual Jealousy

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Male Sexual Jealousy

• Does Domestic Abuse fit HEP model?
• Cumulative cyclical.
• High risk if pregnant potential poachers
  about f young f attractive near ovulation m
  has lost status/resources
• Male may drop in or phone unexpectedly keep
  separate from men fill partners time.
• If drop in if say Id die if you leftgt severe
  risk.
• If holds such viewsgt 2 x risk severe violence.
• If show affection if give resourcesgt low risk.
  

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Quote by a UK 17 year old Female

• My ex-boyfriend was very controlling, he used to
  check my phone, tell me what to wear and who I
  couldnt be friends with. On one occasion he
  slapped me in front of his friends because I
  'answered him back'. He made me feel really bad
  about myself and that I was always the one in the
  wrong. If I did what he said - things would be
  ok. I wish Id known then that his behaviour was
  the problem - not mine.

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Other HEP Hypotheses

• Wilson Daly (1998) argue that extreme (eg
  lethal) IPV is a side-effect of M aggression.
• Trivers-Willard Hypothesis heritable trait that
  helps sons more than f gt more sons.
• Aggression is such a trait.
• F targets of IPV have more sons (Kanazawa 2005),
  plt.001.
• Prenatal Testosterone may be proximate cause.

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A Controversial HEP Hypothesis

• Kanazawa (2008) takes the TWH further
• Aggression helps in m vs m competition.
• F may choose aggressive m as her sons will show
  same traits.
• Yanomamo killers Jivaro war leaders have more
  wives.
• Moulay Ismail the Bloodthirsty, gt1,042 kids, said
  to have killed 30,000 himself.
• Delinquent m have more earlier sex kids.

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Why Would Women Choose Violent Males?

• It is NOT conscious.
• May be learned in childhood.
• Violent men better in competition.
• F prefer m with high status among m peers.
• May be restricted choice.
• May help protect family too?
• Sexual selection may exaggerate trait.

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Conclusion

• Some DV is very gendered, some not.
• IPV is gendered and very serious.
• Males kill mates much more.
• Seem to be evolutionary explanations.
• Uncertain paternity gt Sexual jealousy.
• High T gt high sexual jealousy gt high DA
• Side effect? Adaptation? Sexual selection?
• Surely need to combine perspectives on DA.
• My email is morgank_at_hope.ac.uk Thank you.