Sexual Selection

Evolutionary behaviours - Intrasexual selection - members of one sex (usually males) compete with other members of their own sex for access to members of the opposite sex - mate competition - whatever traits lead to success in this competition will be passed onto the next generation

Intersexual selection - members of one sex (usually female) show preferences for members of the opposite sex who posses certain characteristics (mate choice) - indicate the chances of the mate being able to give protection and support to offspring which makes them more attractive as a potential mate

IDA non-evol. explanation - some critics reject sexual selection for male preferences for younger women - other exp based on social power - younger women easier to control so are preferred as mates - Kenrick - rejected claim men always prefer younger women - teenage males most attracted to women who were 5 years older than them - however teenage sample makes generalisability restricted - men of different ages may not have the same view as teenagers so have to be careful when stating men don't always prefer younger women as it may be due to peer influences in adolescence

IDA - mate choice in real life - studies such as Buss's survey of mate choice may suffer from a serious problem of validity - give us an indication of expressed preferences rather than being a reflection of what actually happens in real life - although a study of actual marriages - Buss - in 29 cultures confirmed that men do choose younger women - statistics show that men who divorce and remarry tend to choose women who are increasingly younger than they are

Parental investment theory claims that men evolved a greater desire for casual sex and would ideally seek sex earlier in relationships - female behaviour would not be subjected to the same evolutionary pressures - over a year, a man could impregnate a large number of women however a women who had sex with the same number of people would only produce a single child - in contrast to women, men lower their standards in short-term mating opportunities and show a marked decrease in attraction following sex - evolved adaptation to bring about a quick departure which prevents them from spending too much time with one woman

Research support - Clarke and Hatfield's undergraduate study - an attractive man or women went up to strangers on the college campus and asked if they would have sex with them among other questions - 75% of males agreed to have sex with them whilst 0% of females agreed - highlights sex differences that men have evolved psychological mechanisms to ensure success in short-term mating undergraduate study - sample is biased - hard to generalise to the greater population - students have high mobility (move around a lot and come into contact with a large amount of people) therefore may not reflect non-western cultures with low mobility - ethics - experimenters decieved pp's as they did not follow through with sex - could have caused embarrassment - lack of ic

Gender bias? - evolutionary approach assumes that it is just men who would have a preference for short-term mating, however, Greiling and Buss suggest that women may also profit from short-term mating as a way of leaving poor-quality relationships or to produce more genetically diverse offspring

Sexual selection should favour high levels of choosiness in both sexes - poor mate choice is disadvantageous for both sexes who will have wasted valuable resources but its more disastrous for women - women have an obligatory biological investment in their children so are more particular in their choice of mate - they like men who are able to invest resources - protect her and any offspring - show promise as a good parent - sufficiently compatible to ensure minimal costs to her and offspring - men - attracted to women who display signs of fertility - indication of their reproductive value - youth and physical attractiveness

Research support - Buss - mate preferences among men and women in 39 diff. cultures - sample of 10,000 but used survey - expressed preferences not actual preferences - women more than men desired mates who were good financial prospects - men placed more importance on physical attractiveness - men wanted mates who were younger than them - both sexes valued intelligence, kindness and dependability sample of 10,000 - individual differences unlikely to affect results - asked both men and women - avoided any gender bias - makes it more generalisable - expressed preferences not real life reflection - survey - element of questionable reliability as there could be an aspect of social desireability - may want to fit the image of the 'ideal' partner and feel pressured into saying what the majority have said

IDA - Hormonal factors in attraction - male preferences subject to factors other than those predicted by sexual selection - research suggests women near the most fertile stage of their menstrual cycle are more attractive to men - supported by a study of lap dancers - miller - calculated tips from lap dancers and various stages in their cycle - at their most fertile stage they gained twice as many tips than at any other stage 

Reductionist - tries to reduce a complex phenomenom of mating preferences down to the differences between males and females, that men prefer short-term mating to spread their genes whereas women benefit from long-term mating as their have an obligatory biological investment in their children  - however other factors may be in play when choosing mates such as emotional factors and how they make you feel such as positive reinforcement - 

· 

Ethical implications - theory can be seen to support gender stereotypes - women stay at home to look after the children as they have an obligatory biological investment in their children and endorses behaviour that allows sexual privaledges and freedoms for men tha women are declined - theory provides an excuse for men who cheat on their partners as it is a biological drive to procreate and pass on their genes - does not protect females from psychological harm - promotes men fulfilling sexual urges