|Wednesday What’s New: Spotted Flowers & Flies|
|Written by Heleigh Bostwick Wednesday, 30 December 2009|
Dark spots on flower petals are especially common in lilies, orchids, and daisies, but have you ever wondered why some flowers have those spots on the petals? It’s probably due to an evolutionary mechanism called insect mimicry. In other words, those spots on the flower petals attract the insects that pollinate them. Take for instance the spotted jewelweed pictured above that is pollinated by small flies.
A study by researchers in England and South Africa asked that very question and published in the December issue of the American Journal of Botany. According to Dr. Meredith Thomas from the University of Cambridge, the study’s primary researcher, "The spots on the flowers mimic the plant's pollinator, a small fly, which is attracted to the plant because of the spots. The plant is dependent on the pollinator for reproductive success, so it's incredibly important that the plant attracts the flies.”
What’s even more interesting is that these spots are not random even though they appear to be. Instead, Thomas discovered that "the plant has evolved a very clever way of distributing the pollinator-mimicking spots around the inflorescence so that they appear random, as if a few flies had just landed on the inflorescence, when in fact the position of the spots is mathematically pre-determined according to the plant's phyllotaxy [or the order and location in which new floral organs are initiated]."
To read more about the specifics behind this adaptive mechanism visit: How the Daisy Got Its Spot: Insect Mimicry