Pistils and stamens reach maturity at different times?

In many flowers, the pistils and stamens reach maturity at different times. Considering what you know about pollination, why would this be an advantage to the plant?

Pistils and stamens reach maturity at different times?
By maturing at different times, the flower is forced to fertilize, or be fertilized by another. This is nature's way of preventing inbreeding and ensuring that the result will be vigorous progeny.
Reply:Maturing at different stages means they won't pollinate themselves. If they can't pollinate themselves, someone else will have to, and that ensures genetic diversity.
Reply:Hi,


According to xkp .... speech, cross breeding is insuring high genetic variability. And that's the way to evolute and maintain the species well-adapted in their environment. So if the maturity of sexual organs occure at different times, cross breeding is an obligate way to reproduction (pollen grains of another plant come to the pistil, grains of that plant will go on another pistil). If the pistil reach maturity first, it's progyny, if stamens reach maturity first, it's proandry. Even if you're a plant, "consanguinity" is not a good way to survive.