Intersexual selection refers to what males and females find attractive in the opposite sex. There are a number of specific predictions follow illustrating intersexual selection. The female evolutionary strategy is to prefer males with signa of quality, commitment and resources, there show desirable traits to pass on in the genes. The male evolutionary strategy is to find females who are young and physically attractive as this shows good health and infertility.
Men will place a high value on chastity or celibacy in their partner as females can be sure any child they produce is theirs and men lack this certainty. This makes the males feel a need to control female sexuality. Such control increases the possibility that nay child the man rears is carrying his genes.
Following on from this, males should protect their women by showing jealousy and should show greater concern about sexual infidelity since it reduces paternal certainty. Females should be more concerned emotional infidelity.
Evidence for intersexual selection can be seen in studies by Buss, Davis and Clark and Hatfield. Buss did a survey across 37 cultures and found that males rated youth and physical attractiveness, and that females rated resources.
Davis’ study supports Buss’ as Davis found gender differences in qualities emphasized in personal adverrtisements. Women tended to emphasise their physical attrativeness and desire for a high-status man, whereas men tented to indicate their resources and their desire for a younger physically attractive partner. This led Davis to conclude that women were looking for “success objects” and men were looking for “sex objects”.
Clark and Hatfield also supported intersexual selection as it provides evidence that females are more discerning than males. In this study male and female college students were approached by confederates and asked if they would sleep with them that night. 75% of males said yes compared to 0% of females, which is evidence that females are more selective in their choice of partner.
The importance of chastity was illustrated in Buss’ cross cultural survey since in 62% of the 37 cultures it was found that males valued chastity more highly than females.
The research studies by Buss, Clark and Hatfield and Davis are natural experiments because gender is a naturally occurring independent variable. Consequently, causation cannot be inferred, we cannot say that behavioural differences are caused by gender and so conclusions are limited. But they may have greater real-life validity then more controlled, artificial research.
Human reproductive behaviour therefore appears relatively universal and supports an evolutionary account. However, sociological factors rather then evolution may account for some of the findings. For example, traditionally the only way females could achieve wealth and status was through whom they married. It is only very recently that females in the UK for example have been able to achieve financial independence and they previously had to rely largely on men to provide for them and their children. Females often only had their appearance to rely upon to attract a male and the preference for men with resources may be due to social factors, which restricted the females’ ability to provide for herself. Evolutionary explanations cannot account for females who do not want children, for males who bring up other men’s children and for homosexual relationships. Love id ignored, which may be a more valid reason for sexual behaviour than reproduction.
Evolutionary theorists predict that reproductive behaviour is consistent across time, when in fact changes do occur. For example, males are far more involved today in child rearing then they were even a generation ago. Evolutionary theory is able to offer a partial account of behaviour in terms of inherited behaviour characteristics, which provides the programming for a particular behaviour. However, they ignore the ‘options’ within that program, and human behaviour needs to be considered as multifactorial; that is, an interaction between nature and nurture. This is illustrated in a study be Strassberg were mate choices preferences were not as predicted. Strassberg’s research on internet dating contradicts the traditional sexual stereotypes, fictitious ads were placed on an internet dating site, which advertised women as “very attractive”, “passionate and sensitive”, or “financially successful and ambitious”. The latter received more replies then the physically attractive condition and this challenges evolutionary explanations – if mate choice preferences were coded in the genes they should be relatively stable and universal.
