Relationships

• Sexual selection is an evolutionary explanation of partner preference. Attributes or behaviours that increase reproductive success are passed on and may become exaggerated over succeeding generations of offspring
• Human reproductive behaviour - this refers to any behaviour which relates to opportunities to reproduce and thereby increase survival chances of our genes. It includes the evolutionary mechanisms underlying our partner preferences, such as mate choice and mate competition.
• Darwin’s (1871) concept of sexual selection concerns the selection of those characteristics that aid successful reproduction (rather than survival).
• The basis of human reproductive behaviour is anisogamy. This refers to the differences between male and female sex cells (gametes). Male sperm are created continuously and in vast numbers, while female eggs are released at intervals for a limited number of fertile years.
• A consequence of anisogamy for mate selection is that there’s no shortage of fertile males, but a fertile woman is a ‘rare resource’.
• There are two types of sexual selection:

  1. Inter-sexual selection (between sexes) - the strategies that males use to select females and females to select males.
  2. Intra-sexual selection (within sexes) - such as strategies between males to be the one selected.
• Inter-sexual selection is the preferred strategy of the female, quality over quantity. Trivers (1972) pointed out that the female makes a greater investment of time, commitment and other resources before, during and the birth of her offspring. Both sexes are choosy, as both stand to lose if they invest resources in substandard partners. But the consequences of making the wrong partner choice are more serious for the female, so it pays for her to be especially selective. Therefore the female’s optimum mating strategy is to select a genetically fit partner who is able to provide resources.
• It is this female preference (quality over quantity) which determines which features are passed on to the offspring. For example, if height is considered an attractive male trait by females, then it would increase over successive generations. This is because, in each generation, females will select the tallest males and thus that characteristic will eventually become exaggerated (a runaway process).
• Fisher (1930)developed a sexy sons hypothesis - the genes we see today are those that enhanced reproductive success. A female who mates with a male who has a certain characteristic then will have sons who inherit this ‘sexy’ trait. Hen her sons are also more likely to be chosen by successive generations of females who will mate with her offspring. Therefore the presence of this ‘sexy’ trait is perpetuated.
• Intra-sexual selection is the preferred mating strategy of males - quantity over quality. There is competition between males to be selected to mate with a female. The winner of the competition reproduces and therefore the characteristics that contributed to his victory to his offspring. This strategy has given rise to dimorphism (meaning ‘two forms’) - males and females end up looking very different due to intra-sexual selection.
• What is an example of dimorphism as a result of intra-sexual selection?


  In any competition between males, size matters. Larger males have an advantage and therefore are more likely to be reproductively successful. On the other hand, females do not compete for reproductive rights so there is no evolutionary drive towards favouring larger females. However, in females youthfulness is selected because males have a preference to mate with younger more fertile women.
• Intra-sexual selection can also have behavioural consequences, although these are controversial. The characteristics that are favoured and passed on are those that allow a male to outcompete his rival, including deceitfulness, intelligence and aggression. Males may benefit from acting aggressively in order to acquire fertile females and protect them from competing males. This leads to the selection of aggressiveness in males.
• Buss (1989) carried out a survey of over 10,000 adults in 33 countries. 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 placed greater value on resource-related characteristics, e.g. good financial prospects, ambition and industriousness. Males valued reproductive capacity in terms of good looks and chastity, and preferred younger mates. Strength - these findings reflect consistent sex differences + support predictions of sexual selection theory.
• Clark and Hatfield (1989) showed that female choosiness is a reality. Male and female psychology students were sent out across a university campus. They approached other students individually asking: ‘I have been noticing you around campus. I find you to be very attractive. Would you go to bed with me tonight?’ Not a single female student agreed to the request, whereas 75% of males did, immediately. This supports the view that females are choosier than males when it comes to selecting sexual partners and that males have evolved a different strategy to ensure reproductive success.
• Partner preferences over the past century have been influenced by social norms of sexual behaviour. These have come about due to cultural factors such as contraception availability. Women’s role in the workplace means that they are no longer dependent on men to provide for them. Bereczkei (1997) argues this change has consequences for women’s preferences, which may no longer be resource-oriented. Partner preferences are now the outcome of cultural and evolutionary influences, any theory that fails to take into account both is a limited explanation.
• Evolutionary theory makes predictions about partner preference that can be empirically tested. One is males prefer a female body type that signals fertility. Singh (1993, 2002), studied this in terms of waist to hip ratio. Up to a point, males generally find any hip and waist sizes attractive so long as the ratio of one to other is around 0.7. This combination of wider hips and narrow waist is attractive as it is a ‘signal’ of fertility. This supports theories of anisogamy and intra-sex selection (men are sensitive to female fertility signals as their reproductive strategy is to mate widely.)
• Waynforth and Dunbar (1995) studied lonely hearts advertisements in American newspapers. The researchers found that women more than men tended to offer physical attractiveness and indicators of youth (‘flirty, exciting, curvy’). Men on the other hand, offered resources (‘successful, fit, mature’), and sought relative youth and physical attractiveness. This supports the idea that females use inter-sex strategies to select sexual partners whereas males compete with each other.
• Self-disclosure refers to the information we choose to reveal about ourselves within a romantic relationship. The aim of self-disclosure is to increase intimacy, empathy and understanding between two individuals (given that it is reciprocal). Self-disclosure has a vital role in a relationship beyond the initial attraction. Most people are careful about what they disclose to begin with
• Altman and Taylor have proposed the 'social penetration theory', which suggests that the process if self-disclosure allows one person to penetrate deeper into the life of their partner, thus increasing intimacy + trust. To go further, the other person must also reveal sensitive information. As they disclose increasingly more information about each other's lives, they gain a greater understanding of each other.
• According to Altman and Taylor, self-disclosure has two elements: breadth and depth. As both of these increase, romantic partners become more committed to each other. The researchers use the many layers of an onion to illustrate this process. We reveal a lot of superficial information about ourselves, low-risk information. The breadth of disclosure is narrow because many topics are 'off-limits'. Revealing too much too soon might threaten the relationship.
• As a relationship develops, self-disclosure becomes deeper. Eventually we reveal more intimate, high-risk information: painful memories, secrets, powerful feelings.
• Reiss and Shaver stated that for a relationship to develop (as well as an increase in breadth and depth) there needs to be a reciprocal element to disclosure. Disclosing something revealing your true self should be met with understanding, empathy, and their own thoughts and feelings. So that there is a balance between both partners.
• Sprecher + Hendrick studied heterosexual couples, finding strong correlations between measures of satisfaction and self-disclosure. (couples who used self-disclosure and believed their partner did were more satisfied and committed to their relationship). Laurenceau used writing daily diary entries. They found that self-disclosure and the perception of self-disclosure in a partner were linked to higher levels of intimacy in long-term married couples. The reverse was also true. + Such studies increase our confidence in the validity of the theory. Although, correlation does not equal causation
• Research into self-disclosure can help people who want to improve communication in their relationships. Romantic partners use self-disclosure skillfully and deliberately occasionally to increase intimacy and strengthen their bond. Hass and Stafford found that 57% of gay men and women in their study said open and honest self-disclosure was the main way they maintained and deepened their connection. Self-disclosure can deepen satisfaction and commitment in relationships. +Real-life application demonstrates the value of psychological insights. Although, only 57% + personality has an impact
• The idea that increasing the depth + breadth of self-disclosure leads to more satisfying and intimate romantic relationships isn't true for all cultures. Tang et al. (2013) reviewed research literature about sexual self-disclosure. They concluded that men and women in the USA (individualist) self-disclosed significantly more sexual thoughts + feelings than men and women in China (collectivist). Both levels of self-disclosure are linked to relationship satisfaction in those cultures. - Limited theory of romantic relationships as based on findings from Western cultures. Counter: social norms
• Social penetration theory claims romantic relationships become more intimate as self-disclosure deepens + broadens. Using this metaphor, relationship breakdown pairs with a self-disclosure reduction. However, theories of relationship breakdown recognise that couples discuss the state of their relationship, attempting to save it, involving self-disclosures of intimate thoughts + feelings, which may contribute to a breakup. - this challenges social penetration theory, deeper self-disclosure may contribute to a relationship breakdown. However, only considering self-disclosure is reductionist.
• Much self-disclosure research is correlational - although it's assumed self-disclosure creates satisfaction, a correlation does not tell us if this is a valid conclusion to draw. Correlational studies can never establish cause-and-effect relationships between two variables (third variable problem). Therefore, correlational studies can't be relied upon to demonstrate the mechanism of self-disclosure relating to the quality of relationships. + This is a methodological issue with correlational studies, though they help in establishing relationships and point a study in the right direction.
• Factors affecting attraction: physical attraction:

  1. physical attractiveness
  2. the halo effect
  3. the matching hypothesis
• Physical attractiveness:

  Shakelford and Larsen (1997) found that people with symmetrical faces are rated as more attractive. This is because it may be an honest signal of genetic fitness.

  people are also attracted to faces with neotenous features i.e. baby-faced, such as widely separated and large eyes. These trigger a protective and caring instinct, a valuable resource for women to reproduce.

  McNulty (2008) found that the initial attraction that brought partners together continued to be an important feature of the relationship after marriage, for at least several years.
• The halo effect:

  People who are judged to be attractive are typically perceived in a positive light. For example, Dion (1972) found that attractive people are consistently rated as successful, kind and sociable compared with unattractive. This means we not only believe that attractive people are ore physically attractive, we expect them to have other desirable characteristics. This also links to self-fulfilling prophecy.
• The Matching Hypothesis:

  a theory of interpersonal attraction which argues that relationships are formed between two people who are equal/very similar in terms of social desirability. This is often examined in terms of physical attraction levels. The theory suggests that people assess their own value and make realistic choices by selecting the best available partners who are likely to share the same level of attraction.
• Palmer and Peterson (2012) found that physically attractive individuals were rated as more politically knowledgeable and competent, even when participants knew they lacked expertise. This halo effect, influencing perceptions of competence based on looks, poses risks to democracy if politicians are judged primarily on appearance. + The halo effect applies to many important areas in life, highlighting how physical attractiveness significantly impacts relationships and judgments in everyday life.
• Towhey (1979) found some people value physical attractiveness less than others. Male and female participants rated how much they liked a target based on a photo and biography while completing the MACHO scale, measuring sexist attitudes. High scorers on the scale were more influenced by physical attractiveness when judging likeability, while low scorers were less affected. - This suggests the influence of attractiveness varies, challenging the idea that it is a key factor in relationship formation for everyone.
• Limitation- The original study on the matching hypothesis (Walster et al., 1966) failed to confirm it, possibly due to unreliable attractiveness ratings as raters only had seconds to judge participants. However, later studies using real partners provide stronger support, reflecting a more realistic approach. Support + Feingold's (1988) meta-analysis of 17 studies found a significant correlation in physical attractiveness between romantic partners, supporting the hypothesis in its narrower form focused on physical appearance.
• Research suggests that physical attractiveness is consistent across cultures. Cunningham et al. (1995) found that features like large eyes, prominent cheekbones, a small nose, and high eyebrows were rated highly attractive by white, Hispanic, and Asian males. Similarly, Wheeler and Kim (1997) found that both Korean and American students associated physical attractiveness with traits like trustworthiness, maturity, and friendliness. +This suggests the stereotype is equally strong in collectivist and individualist cultures, showing minimal influence of cultural relativism.
• Taylor et al. (2011) analyzed online dating site activity, offering a real-world test of the matching hypothesis by examining actual date choices rather than preferences. However, findings contradict the hypothesis, as online daters pursued partners more physically attractive than themselves, disregarding their attractiveness levels. - This challenges the idea that people make realistic dating choices based on mutual attractiveness, as the original hypothesis suggests, contradicting key aspects of this theory.
• Factors affecting attraction: filter theory:

  Kerckhoff and Davis (1962) compared the attitudes and personalities of student couples in short-term (less than 18 months) and long-term relationships. From their research, they devised the filter theory of attraction. This theory states that we are exposed to a 'field of availables', but in order to form a relationship, we must narrow this down to a 'field of desirables', using three filters: social demography, similarity in attitudes and complementarity. The significance of each filter depends on whether the relationship is short/long-term.
• Social demography refers to a wide range of factors which influence the chances of potential partners meeting in the first place. They include geographical location, religion, ethnicity, social class, education level etc. Proximity is key because it provides accessibility, making communication and relationship formation easier. Proximity may trump other dissimilarities in social demographic features. Filtering results in homogamy- you are more likely to form a relationship with someone who is socially or culturally similar.
• Similarity of attitudes: Partners will often share important beliefs and values, particularly because the field of availables has already been narrowed down by the first filter to those who have significant social and cultural characteristics in common. Kerckhoff and Davis found that similarity of attitudes was important to the development of romantic relationships, only for couples who had been together less than 18 months. There is a need for partners at the earlier stages of a relationship to agree over basic values. This encourages deeper communication, promoting self-disclosure.
• Similarity of attitudes:

  there is considerable evidence that most of us find this similarity attractive, at least to begin with. Donn Byre (1997) has described the consistent findings that similarity causes attraction as the law of attraction. If such similarity does not exist (for example, it turns out the partners have little in common after all), then the relationship is likely to not develop further.