A biological "CLOSED" sign.

Although this variety of Helleborus I have in the garden is likely some sort of horticultural franken-flower, and likely sterile, it does still "play the game."

If you look closely you'll see that the two flowers look very different. The lower flower opened a few days ago and most of the anthers have shed their pollen; the anthers on the upper flower are still tightly wrapped around the base of the pistil, and will likely start shedding tomorrow.

The yellow "slug-like" objects in the bottom of the lower flower are most likely empty nectaries (structures that store and exude nectar for pollinators), and the openings have curled up and changed colour. They correspond to the green, cup-shaped structures in the upper flower.

Finally, the green hue and speckles on the petals, although attractive to us, are signals to a prospective pollinator. Bees, for example, use the UV end of the light spectrum. Most likely the green will look black, the pink, white, and the spots will also help point them in the direction of the nectaries.

As the flower ages, sheds pollen, and itself becomes pollinated, these signals change. The colours of the petals fade and the curled, yellow nectaries likely appear advertise their lack of nutrients.

Don't you just love plant biology!!!!!