Evolutionary psychology and its critics

1
Evolutionary psychology-and its critics

• MSc EP module 2006/07
• EP Session 1
• revised 03/01/07

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Coverage in this lecture

• What is Evolutionary Psychology?
• Relationships to
• Mainstream psychology
• Sociobiology
• Other human sciences
• Prospects and problems

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What is Evolutionary Psychology?

• Buss The application of Darwinian principles to
  each discipline within Psychology
• Buller distinguishes Evolutionary Psychology (the
  paradigm theoretical claims, methodology, plus
  empirical results) from (lower case) evolutionary
  psychology (just the field of inquiry)
• Tooby Cosmides emphasize the contrast of EP
  with the SSSM, and the idea of a modular mind

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The standard social science model (SSSM)

• EPs proponents (but particularly Cosmides
  Tooby) contrast the paradigm with the SSSM (may
  be a straw man)
• SSSMs main elements
• Blank slate view of human psychology
• Biology irrelevant
• General purpose learning mechanisms
• Does the SSSM realistically depict modern
  psychology or anthropology?

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An evolved mind composed of modules
From Cassidy, 2006, Public Understanding of
Science, 15, 175-205
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EP and the media

• Evolutionary psychology is an approach to
  psychology, in which knowledge and principles
  from evolutionary biology are put to use in
  research on the structure of the human mind.
• It is not an area of study, like vision,
  reasoning, or social behaviour.
• It is a way of thinking about psychology that can
  be applied to any topic within it my italics
• (Cosmides Tooby, 1997)
• Is EP mainly a way of spinning or re-interpreting
  data? Compare this to the way that the party
  ethos has an impact in spinning the actions of
  government, but maybe little control over the
  actions themselves.

7
EP and the press

• Cassidy EP coverage in the popular press, from
  1995 on, is linked to publications of popular
  books, and differs from mainstream science in
  terms of who writes the articles
• Newspapers find EP stories sexy because EP
  makes controversial claims of an evolutionary
  basis for the differences between men and women
• Monogamy, adultery, rape, child abuse, sexual
  attractiveness, and even the glass ceiling in the
  City, may all have their origins in human
  evolutionary history adapted from Cassidy, 2006

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Adaptedness and the Darwinian approach to
behaviour

• EP claimsThat behaviour is adapted to the EEA
  (environment of evolutionary adaptedness) of
  Pleistocene hunter-gatherers
• That details of behaviour make Darwinian sense
• Claim supported by success of Darwinian medicine
  (Williams Nesse, 1991 Nesse Williams, 1995)
• Fevers during infection Pregnancy sickness

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Pregnancy sickness (Profet)

• Unpleasant for mother, but defends baby against
  teratogens
• Nauseated by spicy, fried/roasted, bitter,
  noxious foods
• Nausea worst in wk 3-14, when organs
  differentiate
• Profet in Barkow et al., The adapted mind
• Women who have most PS have lowest spontaneous
  abortion, so discomfort beneficial
• Severe PS (1.0), mild (3.6), none (7.2)
• (Profet, 1989 British Journal of Obstetrics and
  Gynacology, 96, 1304-1311, 1312-1318)
• Pain is also unpleasant but adaptive

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Trying too hard for an adaptive explanation?

• Acne an adaptation to protect from teenage sex?
• Acne is not an infection action at puberty of
  hormones on (?distinct) follicles
• On face visible. Causes disgust (to protect
  from sexual advances) resolves naturally in
  early 20s when the prefrontal cortex is fully
  mature
• Not a disease, a normal process adapted to ward
  off potential mates during newly-evolved phase of
  adolescence. Resolves when individual has reached
  reproductive and emotional maturity
• How would you test this idea?
• Bloom (2004) Medical Hypotheses 62,
  462-469

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Buss human mate-choice strategies

• Sexes differ in main parental investment
• Females carry child in womb, lactate, and heavily
  involved in rearing
• Males only tiny initial investment (sperm)
  later their resources important for child and
  mother, but not obliged to provide these
  resources
• Sex difference in criteria used in mate selection
  
• Females emphasise resources/ possessions
• Males will emphasize cues to reproductive value
  (e.g. appearance)

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Buss (2)

• Buss translated mate-choice questionnaire for use
  in 37 different cultures
• How does each sex rank various characteristics
  across these cultures ?
• Financial prospects 36/37 had Females gt Males
• Ambition/Industiousness 37/37 had FgtM
• Good looks 37/37 Males gt Females
• Chaste before marriage 23/37 MgtF
• 37/37 Males seek slightly younger partner,
  females seek slightly older partner

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Consequences of sex differences in mate choice

• Differences in male vs. female parental
  investment widely documented in EP
• Lead to differences in attitude to casual sex
• Also differences between in standards acceptable
  for short- vs. long-term relationship
• Can EP/HSB can lead to novel predictions and
  studies

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Sunday Sport science?

• Clark Hatfield I have been noticing you
  around the campus. I find you very attractive.
  Would you (Percentage who said Yes)
• Go out with me tonight M 50 F 50
• Come to my apartment tonight M 69 F 6
• Sleep with me tonight M 75 F 0
• Alternatives
• EP explanation Sex differences in parental
  investment ? greater choosiness in women
• Or (From the audience), Men are slime
  Pinker

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Interpretations of Clark Hatfield

• EP women must invest heavily in child if become
  pregnant, men can avoid further investment, so
  the female brain should evolve to be more fussy
  about offers to have sex
• Social Science interpretation women know the
  risks of unwanted pregnancy, so typically will
  only accept the risk after they have checked the
  person out and decided to commit to a long-term
  relationship

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Follow-up analysis

• Females seek long-term relationships with a
  committed partner, men seek short-term as well as
  long-term sex
• Donald Symons In late C20 America
• gay males typically engaged in short-term
  relationships
• gay females in long-term relationships
• Male vs. female sexual fantasy differs
• Ellis Symons,1997, in Betzig (ed.), Human
  Nature, Ch. 20

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Problems for EP

• Too keen on the orthodox message to pay due
  attention to difficulties with details
• Bullers critiques of the Cinderella effect, etc.
• Tends to claim commonsense trends as predictions
• Kitchers idea of evolutionary folk psychology
• Lack of non-obvious predictions
• Lacks a real evolutionary perspective
• If minds have modules, how do these interact to
  deal with modern problems not from the EEA?
• Not enough attention to individual differences in
  minds

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Things in favour of EP (and HSB)

• Rush of jaw-dropping discoveries about subtle
  details of human mate-choice and sexual behaviour
• Now links also to more obviously mental
  characteristics creativity, humour, choices in
  ultimatum games
• Developmental questions are beginning to be
  addressed

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Reading

• Buller (2005) Trends in Cognitive Sciences, 9,
  (6), 277-283 and replies in issue (11)
• Cassidy (2005) Public Understanding of Science,
  14, 115-141
• Cassidy (2006) Public Understanding of Science,
  15, 175-205
• Buss (2004) Evolutionary Psychology (3rd edn),
  esp. chapter 13
• Betzig (1997) (Ed.) Human Nature