Sunday, July 08, 2007

Orchid Species Employ Deceit for Pollination - Like a Man Faking an Accent

Approximately 10 percent of orchid species employ deceit for pollination.
A rare South African orchid, Disa nivea, always grows amid colonies of amember of the foxglove family, whose flower it mimics. It also exploits thetarget plant's pollinator, a fly. Expecting a nectar reward, the fly comesup empty on the orchid, but since there are plenty of genuine nectar plantsaround, it gets fooled again and again.
The spider orchids, Brassia, have evolved showy flowers with spiderycharacteristics to fool the several species of wasps which stuff theirnests with paralyzed spiders. Thinking she has found victims, the femalewasp repeatedly stings the flowers, pollinating the orchid...
pseudocopulation. Each species of Orphrys orchid is pollinated by the maleof a particular bee or wasp. The orchid flower somewhat resembles thefemale, but its velvety texture and the sexual odor it mimics are the mainattractants.The females of these bees and wasps emerge later than the males, and, notcoincidentally, the orchid blooms before females are active. The male landson the flower and goes through the motions of copulation until it realizesit isn't getting anywhere and leaves. In the process it transfers pollen.It never learns, and will continue trying to mate with the orchid until thefemale wasps emerge."

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