Dioecious refers to a plant or animal species that has distinct male and female individuals. In dioecious plants, such as kiwi and holly, only the female plants produce fruit or seeds, while the male plants are responsible for pollination. This separation of sexes can lead to a greater genetic diversity within the population. In the animal kingdom, many species are dioecious, including humans and most birds. In these species, males and females have different reproductive organs and roles. This reproductive strategy can enhance mating opportunities and increase the chances of successful reproduction in various environments.