English: Geranium incanum (and possibly other Geranium spp. as well; I don't know) has an unusual means of inhibiting self-pollination; at first the anthers are unopened, but they soon ripen, while the pistil is not yet open. At this time the petals still are relatively dark in colour. After a few days the androecium withers and the stamens are shed. The gynoecium now ripens and opens, becoming receptive to pollinators. At this stage the flowers become perceptibly paler, possibly as a signal to pollinators that might be more tempted by pollen or nectar, as the case might be. These two photographs were taken from the same plant on the same day, the flower on the left a few days younger than the other, the difference between the gynoecium and the androecium and the petal colour is visible.