Discuss the relationship between sexual selection and human reproductive behaviour (8+16 marks)
Darwin suggested that species evolve through sexual selection which involves attracting the mate with the greatest fitness and at the same time maximizing the chances of being selected as ‘fit’ themselves. Fitness, in the context of the evolutionary theory, means the ability to reproduce and have offspring, making it more likely for them to pass on their genes to the next generation. To explain this, Darwin came up with the two processes:
Intra-sexual selection refers to the evolutionary process where members of one sex (usually males) compete with each other for members of the opposite sex. For example, males compete with each other to fertilize a female and the victor passes on the trait that made them successful to the offspring, helping to ensure their survival and the passing on of their genes to the next generation.
Inter-sexual selection refers to how members of each sex have innate preferences for mates who possess certain characteristics. These preferences determine the areas in which females and males must compete in. For example, females choose and select the best male available, so if women prefer tall men, this gene will be passed on to the next generation and there would be an influx of tall men in the future. Economic resources could also be another trait which females would be looking for as it gives support and security to the offspring.
Mate choice is a product of mate preferences formed in the EEA. The fundamental principle of mate choice is that it pays to be choosy as the genetic quality your mate possesses will determine half the genetic quality of your offspring. The differences between the sexual behaviours of males and females arise because they are subjected to different selective pressures. Whilst males are able to produce millions of sperm and can fertilise many women, females are more selective because of the higher reproductive costs and the certain maternity.
Support for this theory comes from the study by Clarke and Hatfield.
Intra-sexual selection refers to the evolutionary process where members of one sex (usually males) compete with each other for members of the opposite sex. For example, males compete with each other to fertilize a female and the victor passes on the trait that made them successful to the offspring, helping to ensure their survival and the passing on of their genes to the next generation.
Inter-sexual selection refers to how members of each sex have innate preferences for mates who possess certain characteristics. These preferences determine the areas in which females and males must compete in. For example, females choose and select the best male available, so if women prefer tall men, this gene will be passed on to the next generation and there would be an influx of tall men in the future. Economic resources could also be another trait which females would be looking for as it gives support and security to the offspring.
Mate choice is a product of mate preferences formed in the EEA. The fundamental principle of mate choice is that it pays to be choosy as the genetic quality your mate possesses will determine half the genetic quality of your offspring. The differences between the sexual behaviours of males and females arise because they are subjected to different selective pressures. Whilst males are able to produce millions of sperm and can fertilise many women, females are more selective because of the higher reproductive costs and the certain maternity.
Support for this theory comes from the study by Clarke and Hatfield.