Relationships-evolutionary explanations for partner preferences Flashcards
What is sexual selection?
An evolutionary explanation of partner preference Attributes/ behaviour that increase reproductive success are passed on.
What does it mean if a behaviour is said to be adaptive?
If the behaviour leads to increased survival and reproduction of an organism
What is anisogamy?
Refers to the differences between male and female sex cells
Male cells- small, mobile, continuously produced from puberty to old age
Female cells- limited number and fertile period
Name the 2 mating strategies that anisogamy gives rise to?
Inter sexual selection
Intrasexual selection
What is intersexual selection?
The preferred strategy of the female- quality over quantity
- Women have greater investment in child rearing which means their best bet of having success is to be choosy in their partners
- In particular, they may choose a partner who will offer resources (e.g. protection). this will enhance reproductive success as any child she has will have a greater chance of survival
What is intrasexual selection?
The preferred strategy of men- quantity over quality
- Refers to the competition between males ro be able to mate with a female and pass on his characteristics to offspring
- Competition is necessary as women are a more limited resource
What is the impact of intrasexual selection on behaviour?
Aggression and preference for young women. Mate with as many fertile female as possible
Buss (1989)- support for preferences related to anisogamy
- Surveyed over 10,000 adults in 33 countries asking about their partner preference
- He asked questions relating to age and a variety of attributes that evolutionary theory predicts should be important in partner preference
- He found that females valued resource related characteristics more than males (e.g good financial prospects)
- Males value reproductive capacity (e.g good looks and youth)
- Supports sex differences due to anisogamy and partner preference derived from sexual selection theory
Car and Hatfied (1989)- support for intersexual selection
- 75% of males agreed to have sex with an attractive stranger where as none of the females studied indicated the same willingness
- Suggests that males have evolved mechanisms to increase their reproductive success
Singh (2002)- Waist hip ratio
- Measured waist hip ratio preferences of males for females
- Findings were that males generally find any hip and waist sizes attractive so long as the ratio of one to the other is about 0.7
- This combination of wider hips and narrower waist is attractive because it is an honest signal that the woman is fertile but not pregnant
- This shows the evolutionary factors are reflected through partner preferences
Waynforth and Dunbar (1995)- support from lonely hearts adverts
- Studied lonely heart advertisements in American newspapers to see how men and women describe themselves to potential partners
- Women offered physical attractiveness of youth and sought resources
- Men offered resources and sought youth and attractiveness
- Support the evolutionary explanation of inter sexual selection
What is a weakness of evolutionary explanations for partner preferences?
Ignores social and cultural influences- partner preferences have been influenced by rapidly changing social norms of sexual behaviour. These develop much faster than evolutionary time scales and have instead come about due to cultural factors. E.g womens greater role in workplace means they are no longer dependent on men to provide for them
What is the baby face hypothesis? (An alternative hypothesis)
States that we are attracted to neotonous features such as widely spread eyes and small nose as they trigger an innate caring instinct
