How Can a Bee Find a Hot Drink?

Bumblebees like their nectar hot and can use floral color as a way to find it, according to a study published Thursday.

“What the bees appear to be doing is a bit like us drinking a hot drink on a cold day,” said lead researcher Lars Chittka, a behavioral ecologist at Queen Mary College of the University of London.

“The interesting thing is that bees don’t just prefer the warmer drinks -- they learn to predict the flower temperature from the flower color.”

The study was published in the journal Nature.

The researchers presented bumblebees with artificial flowers that all contained the same amount of sugar water.

Pink flowers were heated to about 69 degrees and purple flowers to about 84 degrees. The bees preferred the warmer purple flowers.

When the temperatures were switched, the bees favored the pink flowers.

The researchers then selected one color for all the flowers but heated them to different temperatures. The bees failed to consistently find the warmest flowers.

The result suggested that the bees relied on color, and not some other heat-sensing method, to discern which flowers were the warmest.

Bee expert Jurgen Tautz, a biologist from Germany’s University of Wurzburg who was not affiliated with the study, said bees work to maintain an elevated body temperature that allows them to forage for food during cooler, less competitive times of day.

The study shows that bees prefer to visit a flower that is “rewarding not only for chemical energy but also for its heat,” Tautz said.