Darwins’ theory of natural selection suggested that all species were motivated by ensuring their survival. From this idea, came the concept of ‘survival’ of the fittest, through which only ‘adaptive’ traits and/or characteristics would be ‘naturally selected’. Darwin came to believe that human reproductive behaviour could be explained through a similar process – sexual selection. Sexual selection represents a ‘special’ case of natural selection, introduced by Darwin to resolve the problem that some traits/characteristics continue to be naturally selected, despite not offering any advantage in terms of survival.
The basic motivation behind sexual selection is that, rather than ensuring our ultimate survival (which is futile as we will surely all die), we are motivated to maximise our chances of reproductive success – in doing this, our DNA will pass on and so indirectly we survive through our offspring. In other words, some behaviours, traits and characteristics continued to be reproduced, even though they made the survival of that species LESS likely.
An example of this might be the peacock’s tail, which has evolved over time to become lengthy and beautiful. However, rather than aiding the survival of the species, a long and vibrant tail actually hinders the survival of the peacock, since it renders him more visible to predators and slows him down. Since the tail offered no survival advantage, Darwin concluded that it continued due to female choice – i.e. they find big, colourful tails attractive and are therefore naturally selected through reproduction/reproductive success of those with the desired characteristic. These theories are considered deterministic because it suggests that genes control behaviour, which doesn’t take into consideration an individual’s free will. The evolutionary psychologists do not usually take the view that we cannot escape our genes, theories themselves can seem deterministic.
According to evolutionary psychologists, human reproductive behaviours can be explained using the same principles of natural and sexual selection. Since all males and females are genetically motivated to achieve reproductive success, both sexes face an adaptive problem – how to find a suitable mate. To find a suitable mate, they must first consider what they NEED in order to maximise reproductive success, then adopt strategies to help us realise it. Given the different roles of our ancestral relatives, males and females could be seen to require very different things and this may be based on parental investment. Parental investment refers to the relative time and effort ‘spent’ on offspring in order to ensure their survival and success, and it can be largely agreed that female investment is heavier than that of the male.
Evolutionary theories lack empirical support; as were proposed after the event, we do not know they are true and so all explanations are inferences only. Complex behaviours are not coded onto the genes in the way suggested by evolutionists. The Genome Project has shown that traits are a consequence of many interlinked gene, which may be inconsistent with evolutionary accounts of human reproductive behaviour.
Female parental investment is heavier, or rather more costly, due to lower reproductive output, or ANISOGAMY. Since females have only one reproductive opportunity per month, fertilisation and by a suitable mate is perhaps more important. Since she carried the burden of pregnancy, childbirth and child-rearing, she needed someone to protect her and provide her with the necessary resources with which to both survive and ensure the survival and safety of her offspring. Males, in comparison, can potentially father numerous with considerably less investment and therefore must compete to display his capability & willingness to remain loyal, investing only in her. “Trophy wives”, “gold diggers” and “sugar daddies” support the validity of the gender differences in mate choice identified by evolutionary theories