Wedekind (1995)

• Aim: 

  To determine whether Major Histocompatibility Complex (MHC) affects mate choice in humans.
• Participants:

  • 49 female and 44 male students from the University of Bern, Switzerland
  • Varied MHC types
• Procedure:

  1. Men wore T-shirts for two nights under controlled conditions (no perfumes, specific diet, etc.)
  2. Women rated the smell of 7 T-shirts (3 similar MHC, 3 dissimilar MHC, 1 control)
  3. Women rated odors for intensity, pleasantness, and sexiness
  4. Women were tested in the second week after menstruation
  5. Double-blind design used
• Results:

  • Women scored male body odors as more pleasant when they differed from their own MHC
  • This preference was reversed in women taking oral contraceptives
• Conclusion: 

  MHC may influence human mate choice, supporting an evolutionary explanation for partner selection.

  • Suggests biological basis for mate selection
  • May explain some fertility issues (e.g., repeated miscarriages in couples with similar MHC)
• Strengths:

  1. Supports evolutionary theory of mate selection
  2. Successfully replicated (e.g., Jacob et al., 2002)
  3. Aligns with animal studies (e.g., Yamazaki et al., 1976 on mice)
  4. Double-blind design minimizes bias
  5. Ethically conducted (consent obtained, participants debriefed)
• Limitations:

  1. Potentially reductionist, ignoring cognitive and sociocultural factors
  2. Limited sample (similar age and culture)
  3. Artificial setting may affect ecological validity