Bumblebees Detect Flowers' Electric Fields: Study

Scientists have discovered that bumblebees can sense the electric signals of flowers.

Flowers produce different attractive signals such as bright colors, patterns and fragrances to communicate with insect pollinators. A new study by researchers from the University of Bristol, U.K., has found that electric fields help flowers to communicate with pollinators such as bumblebees.

Bumblebees acquire positive charge as they fly through the air, whereas flowering plants are usually negatively charged and emit weak electric fields. This made the researchers wonder whether bees that approach a flower could sense the signals. In order to find out, lead researcher Daniel Robert and his colleagues designed fake electric flowers by placing electrodes in the stems of petunias in a laboratory flying arena. Some flowers with a positive charge offered a sucrose reward, while other flowers which did not have any charge offered a bitter quinine solution, reports BBC.

The research team watched bumblebees visiting the flowers in the flying arena 50 times. In the last 10 visits, the bees were able to distinguish between the electric signals emitted by the flowers. Researchers also found that the bees were able to determine whether a particular flower had been recently visited by other bees.

When the electric field was turned off, the bees visited the flowers on a random basis, as they were not able to differentiate between the flowers any more. This showed that the bees were learning using the flowers' electric fields, the researchers concluded.

"This novel communication channel reveals how flowers can potentially inform their pollinators about the honest status of their precious nectar and pollen reserves," Dr. Heather Whitney, a co-author of the study, said in a statement.

The findings of the study, "Detection and learning of floral electric fields by bumblebees", are published in the journal Science Express.