Evolutionary explanations for partner preferences

• Sexual selection 


  the view that competition for mates between individuals of the same sex affects the evolution of certain traits.
• Darwin

  • any physical traits that enhances reproductive success will gradually be passed down and enhanced over evolutionary time.
  • animals therefore possess features that make them attractive to members of the opposite sex and to allow them to compete better with members of the same sex.
• Anisogamy 


  refers to the differences between male and females sex cells (also known as gametes).
• Intersexual selection


  occurs between women who then go on to select men who show the best indicators of providing good genes for offspring, the ability to protect her and her child, provide status and resources. 
• intra-sexual selection


  men competing with one another for the opportunity to mate with a female who determines the features that are passed on to the offspring
• Traits such as height, intelligence, strength, resources etc. are deemed attractive and sought in mate preferences this way by females.
• Zahavi: the “handicap principle”

  if any indicator is too costly to produce and is still displayed, then it must be a sign of strong genes and health. In men, strong jawlines, wide backs and height are all indicators of a strong immune system (high levels of testosterone).
• Males

  most attracted to females who display signs of fertility which is an indication of reproductive value. Men therefore place greater importance on physical attractiveness, youth, their health and appearance when selecting a mate.
• Buss (1989)

  • conducted a cross-cultural study over 37 cultures with over 10, 000 people on mate preference.
  • Males reported to prefer younger physically attractive females
  • Females sought physically strong and athletic males with an emphasis on resources.
  • Both are therefore engaging in behaviour that increases reproductive success supporting sexual selection theory.
• Issue with Buss’ research

  • questionnaires were used which can be easily misunderstood across cultures.
  • self-reports may be inaccurate and translation problems could have easily occurred through the use of third party translators invalidating the findings.
• Bernstein (2015) - cultural traditions may be just as important as evolutionary forces

  argued that gender differences in mate preferences may be a result of women having been denied economic and political power which might account for their need to rely on security and resources rather than anything to do with evolutionary pressures which undermines this theory.
• Sharma et al (1999)

  • conducted an analysis of 37 cultures demonstrating that women who were from cultures where opportunities were limited placed higher value on resources.
  • suggests that although evolutionary forces may be at work in mate selection, we can not rule out social or economic factors in mate preference either which undermines evolutionary explanations as a holistic explanation.
• Research support for inter-sexual selection: Clark and Hatfield (1989)

  • study demonstrated how female “choosiness” was a reality of heterosexual relationships.
  • Male and female students were sent out across a university campus and told to approach students individually offering to mate
  • Not a single female agreed to the males requests however 75% of males agreed to the females request to sleep with them. 
• Singh (1993)

  found men preferred waist to hip ratios of 0.7 across cultures. This is typical of the hourglass figure and a sign of fertility which would support sexual selection theory as this demonstrates to males she has the qualities required to rear children
• reductionist

  they simply put down mate choice due to our genetic makeup and biological urges. In truth partner choice is much more complex involving cultural and social elements which are not fully considered and this theory portrays us as driven purely by nature which is clearly not true.
• deterministic

  • suggests human sexual preferences are genetically programmed and we are at their mercy.
  • does not take into account our ability of conscious thought which gives us free will to make choices for ourselves.
  • Even in Buss et al’s study across cultures “kindness” and “intelligence” was ranked higher than physical attraction.
• Sexual selection theory cannot also explain homosexuality and why this exists.

  No children are produced and such behaviour goes against the theory. This raises serious ethical issues as people may use sexual selection theory to highlight the “abnormality” of homosexuality and create prejudice through homophobia.