Relationships : Evolutionary Explanations Flashcards
What is evolutionary explanations
Evolutionary explanations for partner preferences focus on sexual selection as the driving force of human reproductive behaviour, as those who manage to reproduce successfully will pass on their genes.
What is Human Reproductive Behaviour?
Human reproductive behaviour is a term used by evolutionary psychologists to refer to the different behaviours that humans exhibit in order to increase their reproductive success.
What is sexual selection?
According to Charles Darwin, sexual selection is a type of natural selection and competition for mates along with the development of characteristics that aid reproductive success drive evolution
What is Evolutionary approach?
- Evolutionary approaches explain human behaviour in terms of adaptiveness and reproductive success.
- These approaches argue that if a behavioural feature (for example, aggression) has been genetically inherited by one generation from another, then it must have a specific value for human species; it might either help humans adapt better to the environment and survive ( natural selection) or might help to attract a mate ( sexual selection)
What is anisogamy?
differences between male and female sex cells.
What is Inter - Sexual selection?
- Inter- sexual selection is sometimes referred to as ‘female choice’, because it’s based on the idea that due to the greater investment of time, energy and resources required from a female to raise a child, females need to be more careful when choosing a partner.
-They need to be sure that their partner will provide the right genetic fit and will be willing to provide resources to support the female and the child.
What did Clark and Hatfield do?
- They asked male and female student volunteers to approach opposite sex students individually on a university campus, asking the same question:
-I’ve noticed you around the campus. I find you very attractive. Will you go to bed with me tonight?’ - They found marked gender differences in the responses: 75% of male students agreed; however, not a single female said ‘yes’.
What is Intra-sexual selection
- Intra-sexual selection, on the other hand, is a preferred male strategy. It refers to the evolutionarily developed features that allow a male to compete with other males for a female mate.
- The winner of this competition reproduces and passes on to his offspring the genes that contributed to his success.
- For example, a physically stronger and larger male will be able to fight off his competitors for access to the female, so he will produce physically stronger sons.
How can intra - sexual selection explain the difference physically between male and female?
- Intra-sexual selection also can explain the differences in the body size and physical appearance between males and females (this is known as physical dimorphism). As males need to compete with other males for an access to a fertile mate, sexual selection favours physically strong and aggressive males.
-However, females don’t need to physically compete for a mate, meaning that physical strength and aggression will hold no evolutionary advantage for them.
What did David Buss do?
- These differences in mating strategies were demonstrated by David Buss (1989), who surveyed over 10,000 adults in 33 countries.
- Buss found that females universally put more importance on resource-related characteristics in a partner, such as ambition, high intelligence and good financial prospects.
-Males, however, preferred younger mates and put more value on signs of a female’s ability to reproduce, such as attractiveness and modesty
Evaluation of the Evolutionary explanations of relationships
- Evolutionary explanations ignore social and cultural influences. For the past 100 years, Western societies have experienced significant changes in terms of gender equality and women’s independence. These changes mean that women in modern Western societies may no longer be looking for a man to provide them with resources; and other qualities in a mate become more important.
- Another criticism of evolutionary psychologists’ claim that women universally prefer high-status and well-resourced men comes from the methodological weaknesses of research to support this claim. Most of the studies into females’ choice of mates were carried out on undergraduate students. As these women were expected to achieve a high education status leading to a secure income, their preference for high-status men may stem from similar interests and prospects, rather than be a search for a resourceful mate.
Dimorphism
- Refers to the differences between males and female.
- Same species but clear differences in shape and size.
Study by Devendra Singh
- Aim : to prove male will show a preference for a female body shape that signals fertility.
- studied waist-hip ratio (WHR).
- Up to a point , males find any hip and waist sizes are 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 ‘ ( it is hard to fake) that the woman is fertile but not currently pregnant.
Study by Waynforht and Dunbar
-studied lonely hearts advertisements in American newspapers. The researchers found that woman more than women tended to offer physical attractiveness and indicators of youth (‘flirty,exciting , curvy , sexy’). Meant , on the other hand , offered resources more than man (‘successful, fit , mature, ambitious’) and sought relative youth and physical attractiveness.
- It supports sexual selection because woman wants the best man who will support and care for them. Whilst also man want woman who do not show fertility.
- An issue with this study is that it may like temporal validity because in todays age you can see pictures of the woman now and also it is online.
Key study : This is Buss (1989)
- David Buss (1989) carried out a survey of over 10,000 adults in 33 countries. He asked questions relating age and a variety of attributes that evolutionary theory predicts should be important in partner preference. He found that female respondents placed greater value on resource related characteristics, such as good financial prospects, ambition and industriousness, than males did. Males valued reproductive capacity in terms of good looks and chastity and preferred younger mates more than females did.
- These findings reflect sex difference in male strategies due to anisogamy. They support predictions about partner preference derived from sexual selection theory. Furthermore the findings can be applied across varstly different cultures, reflecting fundamental human preferences which are not primarily dependent upon cultural influences.
