When it comes to relationships the evolutionary approach believes that we choose a partner to maximise our ability to produce children. Sexual selection involves the selection of characteristics that increase reproductive success. For example, if a bird’s [peacock] plumage enhances his prospects of being chosen as a mate, the characteristic is passed on and becomes enhanced as a sexually selected one. This is known as intra-selection where the female chooses what characteristics are selected for and passed on through the generations
Human beings are perceptually ‘pre-programmed’ to attend to displays of these important indicators, which in turn increases their willingness to mate with the individual who possesses them. Therefore, For example, if females prefer tall males, over time there would be an increase in the number of tall males in the population. Females seek males displaying genetic fitness, such as strength, status and resources.
Males produce a lot of small, highly mobile sperm and can fertilise many females at little cost to reproductive potential. They cannot be sure of paternity, so natural selection favours male behaviours maximising the number of potential pregnancies. This results in intra-sexual selection, where members of one sex (usually males) compete with each other for access to members of the opposite sex. Males seek females displaying signs of fertility, such as health, youth and childbearing hips. The women are the prize for the winner of these contests. Again as with intra-sexual selection whatever traits lead to success in these same sex contests will be passed on to the next generation.
Females produce few eggs, in contrast to males, each egg represents a sizeable reproductive investment. Natural selection favours female behaviours maximising chances of each potential reproduction being successful, such as careful mate selection, monogamy and high parental investment. Therefore, Females indulge in inter-sexual competition,...