sexual selection

• sexual selection:

  • evolutionary explanation for preferences
  • attributes/behaviour increase reproductive success, may be exaggerated over succeeding generations
• anisogamy:

  • difference between male + female gametes
  • size, mobility, quantity, time window
  • fertile females are a rare resource - leads to different mating strategies
• inter sexual selection:

  • sexual selection between sexes - preferred for females (quality over quantity)
  • less gametes, greater investment of time, commitment - consequence of wrong choice is bigger, more choosy
  • optimum strategy = genetically fit partner, passed down to offspring e.g height (sexy sons hypothesis)
• intra sexual selection:

  • sexual selection within sexes - preferred for males (quantity over quality)
  • successful competitor will pass down characteristics - led to dimorphism (men bigger than woman)
  • larger males have advantages - behavioural consequences = acting aggressive to keep mates
  • optimum strategy = as many fertile females as possible
• attractive body shapes:

  • empirical research support - size doesnt matter shape does
  • women = hourglass, men = inverted triangle
• EVALUATION: research support for anisogamy

  • buss - 33 countries, 10000 adults, questions related to age + partner preference
  • findings = women valued financial prospects, men valued good looks + chastity
  • reflects sex differences + applied to cultures
• EVALUATION: research support for inter sexual selection

  • clark + hatfield - volunteers approached opposite sex students on campus asking if theyd like to go to bed
  • findings = 0% females, 75% males agreed
  • supports theory - women are choosier, different strats for reproductive success
• EVALUATION: ignores social + cultural differences

  • bereczkei - social change has consequences for womens preferences (no longer resource orientated)
  • greater role in workplace, dont have to rely on men
  • mate preferences = combo of evolutionary + cultural differences, reductionist
• EVALUATION: more complex

  • penton-voak et al - preferences change over menstrual cycle, fertile = masculine, feminised for longer term
  • masculine = healthier immune system, feminine = kindness + parental cooperation
  • preferences based on range of factors rather than genetics