Essentially, the flower “creates ways to select or control the identities of its pollinators,” he said. The hummingbird’s niche is being strong and capable enough to feed at difficult angles, and the bloom benefits because the bird casts pollen so widely.
Coevolution, the process in which two species evolve in lockstep with each other, is a phenomenon that dates back to Charles Darwin. Darwin was intrigued by an odd orchid Angraecum sesquipedale. The star orchid is a beautiful flower, sure, but it was the flower’s long nectar tube that intrigued Darwin, he posited that in order for the flower to survive, it would require a pollinator with a very long proboscis that mimicked the flowers odd morphology. Darwin was ridiculed for this suggestion because no such thing had ever been seen in Madagascar. And then, lo and behold, four decades later Darwin’s prediction was proven correct upon the discovery of the hawk moth and its amazing proboscis.
In the case of these droopy flowers and their sugar-fueled avian pollinators, the balance is more subtle. Droopy flowers mean hummingbirds have to expend more energy to reach the nectar, but the nectar is more pure (not having been diluted by rain or harvested by insect pollinators). For the flowers, they become dependent upon a single species, but that single species has a great memory and is wide ranging, which means that the flower’s genetic material will be spread farther afield than if the flower relied upon buzzier buddies. Evolution is so amazing, wouldn’t you agree? ~AR
(via Droopy Flowers and Their Wiles - NYTimes.com)