Evolutionary Explanations for Partner Preferences

• What is Sexual Selection?

  • Individuals with genes that make them attractive to the opposite sex are more likely to reproduce
  • Often this can produce features that are otherwise harmful to survival
• What is Human Reproductive Behaviour?

  Behaviours which relate to opportunities to reproduce and thereby increase the survival changed of our genes
• What is Anisogamy?

  Male and Female sex cells are different so investment in offspring is unequal
• What does Anisogamy lead to?

  • Inter-sexual selection
  • Intra-sexual selection
• What is Inter-sexual selection (Mate Choice)?

  • One sex will prefer members of the opposite sex with certain qualities
  • The chosen ones get to pass on their genes
• Who came up with the Sexy Sons Hypothesis?

  • Fisher
• What is the Sexy Sons Hypothesis?

  • Females mate with a male who has a desirable trait e.g. height and passes this trait to her son
  • Thereby increasing the likelihood that future generations of females will mate with their offspring
• What is Intra-sexual Selection?

  • Members of one sex compete with each other for access to the other sex
  • The victors get to pass on their successful genes
• What are Short-Term Mating Preferences?

  • Males are able to impregnate a large number of females over a short period of time
  • Spreading their genes as much as possible (Low investment)
  • They have evolved a greater desire for casual sex
• What are Long-Term Mating Sequences (Women)?

  Women have a greater biological investment in their offspring, so seek males who:

  • Have resources to offer her and her children
  • Can protect her and her children
  • Show promise as a parent
• What are Long-Term Mating Preferences (Men)?

  When men do decide to settle down, they don't want to waste their resources, so they choose females who are:

  • Young
  • Healthy
  • Attractive

  (Indicators of Fertility)
• Strength of the Evolutionary Explanation - Supporting Research

  • David Buss
  • Carried out a survey with over 10,000 adults in 33 countries
  • Asked questions relating to age and a variety of attributes the evolutionary theory predicts should be important
  • Female respondents reported placed greater value on resource-related characteristics
  • Males placed more value on reproductive capacity in terms of good looks and being younger
• Strength of the Evolutionary Explanation - Supporting Evidence

  • Clark and Hatfield
  • Male and female participants were sent out across a university campus
  • They approached other student telling them they thought they looked attractive and asked if they would sleep with them
  • 0% of females said yes compared to 75% of males
• Limitation of Evolutionary Explanation:

  • Ignores Social and Cultural influences
  • Bereczkei - Due to changing positions of women (becoming more independent) their mate preferences are no longer resource oriented
• Limitation of Evolutionary Explanation:

  • Deterministic and ignores the influence of free will
• Limitation of Clark and Hatfield's research:

  • Low population validity
  • Only used psychology students
  • People of different ages could have yielded different results
• Strength of David Buss' research:

  • High population validity
  • 10,000 respondents across 33 countries