By Carol Clark
Even flowers need their sweethearts.
Global declines in pollinators such as bees could have a bigger impact on flowering plants and foods than previously realized, found an Emory ecologist.
The interactions between bumblebees and larkspur wildflowers in Colorado’s Rocky Mountains were the focus of the study, published by the Proceedings of the National Academy of Sciences.
Most pollinators visit several plant species during their lifetime, but often they will display what is called “floral fidelity” during shorter time periods, says ecologist Berry Brosi, who led the study. They’ll tend to focus on one plant while it’s in bloom, then a few weeks later move on to the next species in bloom. “You might think of them as serial monogamists,” he says.
Reduced competition among pollinators disrupts floral fidelity, or specialization, among the remaining bees in the system, the study showed, which leads to less successful plant reproduction. “These wildflowers produce one-third fewer seeds in the absence of just one bumblebee species,” Brosi says. “That’s alarming.”
The experiments were conducted at the Rocky Mountain Biological Laboratory. Much of the “bee team” was made up of Emory undergraduate students, funded by the college’s Scholarly Inquiry and Research at Emory grants and NSF support.