According to Charles Darwin, sexual selection is a type of natural selection and competition for mates along with the development of characteristics that aid reproductive success drive evolution. Intrasexual selection (mate competition) is one type of sexual selection, where members of the same sex compete with one other for members of the opposite sex. Those who ‘win’ are able to mate and pass on their genes to the next generation. Intersexual selection (mate choice) involves one sex having preferences for members of the opposite sex who possess certain qualities.