Movement in Lily Anthers
The hybrid oriental lily (Fig. a) seems to be equipped for both wind and insect pollination. However, given that there has been extensive human intervention in the production of these hybrids, it cannot be assumed that the design features have arisen purely by evolution through natural selection. As in most ornamental lilies, both the stamens and the style are prominent (Fig. b) and they have the added attraction that the anthers seem to hang so loosely on the filaments that they can move about in the breeze.
The filaments are connected to the centre of the anther rather than to one end. An extended focus image of the junction between the filament and the anther (Fig. c), shows that the final half millimetre or so of the filament tapers from its normal width of ca. 0.5 mm to about a third of that. At the point of attachment there is a small (ca. 0.5 mm diam.) hemispherical dome projecting from the under surface of the anther (look at Fig. c in full resolution). The combination of the finely tapered filament and the raised junction that the dome creates, convey just enough rigidity to hold the stamen in an upright position in still conditions, but also enough flexibility to allow it to move about in all planes, in a breeze, or when the plant is shaken.
Whether this helps the anther to shed pollen is unclear, but the movement in the anthers certainly adds to the visual attractiveness of the flower, and it may also serve to attract insects.
