Relationships (Sexual selection and Human reproductive behaviour (Intra -…
Sexual selection and Human reproductive behaviour
Sexual selection explains why some characteristics that may seem disadvantageous actually confer an advantage in human reproductive behaviour because the characteristics are attractive to mates.
Some characteristics provide an advantage over competitors for reproductive rights e.g. greater height, secondary sexual characteristics, certain facial and bodily features).
Differences in female and male reproductive cells
Created continuously from puberty to old age
Don't require that much energy to reproduce
No shortage of fertile males
Produced in intervals
Limited number of fertile years
Require a huge investment of energy
Fertile woman is a 'rare' resource
Gives rise to 2 different mating strategies
Inter - sexual selection
BETWEEN the sexes: Strategies that males use to attract females and the strategies that females use to attract males
Intra - sexual selection
Strategies WITHIN each sex: Strategies between males to be the one that is selected.
Inter - Sexual Selection
Preffered strategy of the female: Quality over Quantity
Eggs are harder to produce and therefore rarer than sperm
Females are the sex that invest the most time, commitment and other resources, before, during and after the child is born
Both sexes are choosy - both set to lose if they choose the wrong partner
Females are at greater risk if they do choose the wrong partner though
Females optimum mating strategy is to select a genetically fit partner who is available and willing to provide resources.
This leaves the males competing for an opportunity to mate with the fertile female.
Intra - Sexual selection
Preferred strategy of the male - quantity over quality
Competition between intra-males to be able to mate with a female: Winner reproduces and gets to pass on genes that has contributed to his victory
Larger males have an advantage and are therefore more likely to mate.
Has behavioural and psychological tendencies
Males may need to have aggressive behaviour to protect their females and warn off male threats. They may also need to think in a certain way.
Anisogamy dictates that the males optimum survival strategy is to mate with as many females. It wouldn't require that much energy to fertilise every woman on earth and there is a lack of responsibility that the males have when the woman is pregnant
Behavioural consequence of competition for fertile mates is a distinct preference for youth and a sensitivity of indicators of youth e.g facial features. Males are also sensitive to the indicators of fertility e.g. a certain body shape of wider hips.
Research support for preferences related to anisogamy
Carried a survey of over 10,000 adults in 33 countries
Female pts placed greater value on resource related characteristics e.g. good financial prospects, ambition and industriousness.
Asked questions relating to age and a variety of attributes that the evolutionary theory predicts should be important to partner preference
Males valued reproductive capacity in terms of good looks and chastity and looked for younger mates compared to women.
Reflect sex differences in mating strategies of men and women - A woman needs someone who can protect them and provide for their young. A man tends to go for a woman who is younger so that there is more chance of a healthy egg being fertilised as well as a good figure to hold the baby.
Research can be applied across different cultures a it was carried out in 33 countries. This proves that fundamental human preferences are not limited to one culture/country and can therefore be generalised to a wider range of people.
Research support related to Inter - sexual selection
Clark and Hatfield
Female 'choosiness' is a reality of heterosexual relationships
Female and male psychology pts asked fellow students whether they would sleep with them that night
No women agreed to having sex with the men that night but 75% of men agreed to sleeping with the female particpants that night.
Supports evolutionary theory - suggests that women are more choosy when it comes to selecting males and that males must have a different mating strategy (Intra-sexual selection)
Ignores social and cultural influences
Partner preferences over the past century have been influenced by rapidly changing social norms
They develop faster than evolutionary timescales imply and have come about by cultural factors such as availability of contraception
Women have a greater role in the workplace now
No longer dependent on men to provide for them
Bereczkei says social change has consequences for women's mate preferences: no longer look for a resourceful man.
Chang - study in china over 25 years whereby some preferences had changed over the time, but some had not.
Mate preferences are the outcome of a combination of both evolutionary and cultural differences - any theory that doesn't is limited.
Support from Waist to hip ratio research
Men should show a preference for women with wider hips so that they can carry the baby more easily.
Singh - Men find it most attractive when hip to waist ratio is about 0.7
It is attractive because this is an 'honest' signal (it is hard to fake). Shows that the woman is fertile but not pregant.
Support from lonely hearts research
Waynforth and Dunbar
Studied 'lonely hearts' advertisements in american newspapers.
The advertisements were opportunities for men and women to describe the qualities they wanted in a partner and also explained what they had to offer.
Found women more than men offered physical attractiveness and indicators of youth
Found men offered resources more than women did and sought relative youth and attractiveness
Supports research conducted by Buss whereby women look for resources and men look for a younger, more attractive woman because this is an indicator of fertility
Factors affecting attraction
Factors affection attraction - Filter theory
Kerchoff and Davis shows that filter theory is prevalent in todays society.
Compared long term relationships (18 months +) to shorter term relationships (18 months -) and found that similarity of attitudes was more important in the success in short term relationships and complimenting needs was more important in longer term relationships.
Levinger replicated kerckhoff and davis study and found no evidence that simpliacity of needs and complementarity of needs affected relationship development.
Anderson found that similarity in attitudes became even more important as the relationship developed, showing that complementarity may not be the most important factor later on in the relationship.
Gruber also found that similarity in attitudes was still the most important factor even after 14 years.
Kerckhoff and Davis devised a filter theory to explain how short and long term relationships form and develop.
Not everyone who is available to us is desirable
We all have a field of variables which are factors that have been narrowed down. Each of these factors can be of greater or lesser importance in different stages of a relationship.
Wide range of factors which determine whether two people meet or not.
Include geographical location, level of education, ethnic group, religion etc.
Our most meaningful connection with people are with those who a nearer by.
Key benefit of proximity - availability. E.g. we are more likely to meet someone who goes to the same school etc.
Our choices are constrained by our social circumstances.
Anyone who is too 'different' is discounted as a potential partner
Outcome of the filter theory - Homogany: more likely to form a relationship with someone who is socially or culturally similar.
You are more likely to have things in common with people who share the same social or culture values.
Similarity in attitudes
Field of variables has already been narrowed by the first filter meaning that you are more likely to have things in common with the partner.
Kerckhoff and Davis found that similarity of attitudes was important in the development of romantic relationships, but only for couples who had been together less than 18 months.
This stage promotes self disclosure - helping the couple to become closure
Similarity is said to be attractive - Byrne stated that the relationship is likely to fizzle out if a romantic relationship doesn't have similaritys.
3rd filter concerns ability of romantic partners to meet eachothers needs
Partners should complement each other when one has something that the other lacks e.g. one might be outgoing, the other may be shy or quiet.
Kerckhoff and Davis found that this filter was more important in longer term couples - at a later stage in the relationship, opposites attract.
Gives the feeling in a relationship that together, they are whole and complete - they are therefore more likely to flourish.
Evolutionary theory explains why Physical attractiveness is so important when considering factors of attraction
Shackelford and Larsen found people with symetrical faces are rated as more attractive. This is because it may be an honest signal of having good genes.
People are also attracted to a person with a so called 'baby face'
which could indicate a caring individual which is beneficial, especially to a female who is looking to reproduce successfully.
Mcnulty found that attractiveness is not only important in the first stages of a relationship, but also as the relationship develops.
We have preconcieved ideas about personality traits of an attractive person and they are most likely to be positive.
Dion - physically attracted people are consistently matched with traits such as caring, kind and successful.
We behave positively towards physically attractive people.
One distinguishing feature can have a disproportionate effect on our judgement of a persons attributes e.g. their personality.
The matching hypothesis
Common sense tells us we cannot form a relationship with everyone we find attractive
Walster suggests that our own attractiveness rating can effect who we find attractive.
People choose romantic partners who are of similar physical attractiveness to them. This means we have to make an assumption about our own attractiveness level.
We desire the most physical attractive person possible for a number of reasons.
We balance our desires for the most attractive mate by compromising and reducing being rejected
Peterson and Palmer found physically attractive people were more politically competent that non attractive people. This halo effect was so strong that it persisted even when people knew that the attractive people had no expertise.
This has implications for the political prowess inferring that people in politics may have only been put in the job because they were attractive and without expertise.
This confirms that physical attractiveness is very important in the forming of a relationship.
Research support for the matching hypothesis
Feingold conducted a meta analysis and found that there is a strong correlation between ratings of attractiveness between partners
Feingold looked at actual partners which is more realistic.
Role of Cultural influences
Cunningham found that female with large eyes and high cheek bones were attractive to white, hispanic and asian men.
Also - Wheeler and Kim found that Korean and American students observed physically attractive people to be more intelligent which shows that the stereotype also occurs within collectivist cultures as well as individualist.
Social Penetration Theory
Major concept in Altman and Taylors social penetration theory of how relationships develop.
Gradual process of revealing your inner self to someone else.
In romantic relationships - involves the reciprocal exchange of intimate information between partners.
When a partner reveals information they gain trust and to go further they must also reveal sensitive information.
More information that is revealed - more penetration into each others lives
Breadth and depth of self disclosure
Altman and Taylor - Self disclosure has two elements: breadth and depth
As breadth and depth increases, partners will become more commited to one another.
Metaphor of onion layers.
We disclose a lot about ourselves at the start of a relationship but it mostly superficial and 'on the surface' information. This is what we call LOW RISK information - things we would reveal to anyone: aquitances, friends etc.
Breadth of disclosure is normally off limits at the start of a relationship
As relationship develops, self-disclosure becomes deeper - removing more of the 'onion layers' to reveal a wider range of topics, especially those that matter the most to us. Eventually in a relationship both partners should feel ready to reveal intimate information about one another.
Reciprocity of Self DIsclosure
Reis and Shaver points out that there needs to be an element of reciprocity when disclosing information in a partnership.
The idea that once one person discloses information about themselves then the other person will do the same.
A relationship is said to be more successful if there is an element of reciprocity in terms of self disclosure. This eventually leads to a couple feeling more intimate and brings them closer together.
By revealing ourselves to another person, we reveal our likes and dislikes, hopes and fears, interests and attitudes. This makes partners understand each other more. Most people are cautious about the information that they reveal to begin with but eventually self disclosure acts as something that brings a relationship closer together.
Sprecher 2013 - People in partners whereby one half of pts were in the group where self disclosure was recipricol and the other half were in the group where self disclosure was one sided.
Supports the idea that reciprocation is essential to a successful relationship.
Sprecher and Hendricks - positive correlation between amount of self disclosure and relationship satisfaction
Tang - cultural differences questioned the importance of self disclosure in countries like china and Japan (more private and do not disclose that much information). This goes against the theory of self disclosure as it isn't universal and therefore we cannot generalise it globally.