Bees and Flowers Out of Sync, Climate Change Blamed

A new study has revealed that more and more specialized flowering plants may wind up missing out on pollinators as the spring season grows warmer for many parts of the world. As net temperatures continue to climb, researchers have found that bees are waking from their wintering earlier, disrupting a synchronized bloom that some flowers had painstakingly adapted for.

That's at least according to a new study published in the journal Current Biology, which details how the Early Spider Orchid (Ophrys sphegodes) usually boasts an impressively synchronized bloom with the bee Andrena nigroaenea.

According to historical records and ecological observation dating back to 1848, this flower and bee pairing was a prime example of how flawless timing could promote absolute efficiency in nature. Compared to many less specialized flowering plants, the Early Spider Orchid only flowers for a very short amount of time. Amazingly, this narrow window is usually perfectly timed to begin when A. nigroaenea males wake from their wintering slumber before their female counterparts.

Past studies have found that the flower then releases a deceptive scent that resembles the female-produced sex pheromone of the solitary bee species, drawing in males and promoting a high rate of pollination. When the flowers' bloom peaks, the female bees wake, eventually distracting the males from their work.

"These orchids have evolved so that when spring comes, their flowers appear at the same time as this specific bee - making pollination possible," researcher Karen Robbirt said in a statement. "But we have shown that plants and their pollinators show different responses to climate change, and that warming will widen the timeline between bees and flowers emerging."

"Warming by as little as 2 degrees Celsius causes the males to emerge much earlier, meaning they are less well synchronised with the orchids," added lead researcher Anthony Davy. "The problem is compounded by the female bees which are also emerging earlier, and attracting the attention of the male bees. This means that the male bees are more likely to copulate with the female bees, rather than pollinating the orchids."

Davy believes that this change, already causing trouble for specialized flowers like the Early Spider Orchid, will eventually lead to widespread breakdown of co-evolved interactions, threatening species across the globe.