I recently made a few posts, HERE and HERE, about the suburban wildlife sanctuary that is my parent's yard. But there's more. One evening, I purposely hung out in the backyard as dusk passed into darkness to record the opening of a very special flower; a truly spectacular blooming.
This VIDEO shows the almost magical opening of the flowers. I set my camera on a tripod and let the video roll. Once a flower reaches critical mass, it only takes about two minutes, if that, for the structure to go from tightly rolled bud to fully open flower. You can easily see the whole process unravel before your eyes. No sooner has the flower popped fully open than a moth shoots in to investigate. The reason that evening-primrose flowers open at night is to lure their primary pollinators, moths. The plants' flowers are noctodorous; they release a subtle fragrance at night to lure the lepidopterans. Thanks to Chris Coulon for editing my video footage.
Evening-primrose flowers are hermaphroditic; they contain both male and female parts and thus are self-compatible. Deep in the recesses of the corolla in the center of the flower are the nectaries; the sugary goodies sought by pollinating moths. The eight stamens tipped with their pollen-coated anthers project from the flower's center. Also jutting from the depths of the flower and projecting further outwards is the style, which is capped with a curious four-parted stigma. The style and its stigmas can be seen at the bottom of the flower, laying lax against the petals. It is the stigmas that must receive the pollen from the anthers in order for the plant to be successfully pollinated.
Drawn by the flower's odor, the moth navigates to the center of the bloom and plunges its long threadlike tongue deep into its depths to reach the nectar. Well, as anyone who has ever observed a moth knows, they are somewhat clumsy and quite fluttery - hardly the exacting aerialists that hummingbirds are. So, in the process of nectar-diving, the somewhat oafish moth bumbles into that mini forest of stamens and their pollen-dusted anthers. Pollen then adheres to the insect's fuzzy body. Further bumbling by the moth is likely to cause it to glance off the dangling stigmas as it drops from the flower once it has sated itself with nectar. Thus, in the blink of an eye the unsuspecting moth transfers the pollen to the necessary receptors and that will eventually lead to fertile sed and new evening-primrose plants.