Bumblebees sense electric fields in flowers
As they zero in on their sugary reward, foraging bumblebees follow an invisible clue: electric fields. Although some animals, including sharks, are known to have an electric sense, this is the first time the ability has been documented in insects.
Pollinating insects take in a large number of sensory cues, from colours and fragrances to petal textures and air humidity. Being able to judge which flowers will provide the most nectar, and which have already been plundered by other pollinators, helps them to use their energy more efficiently.
It has long been known that bumblebees build up a positive electrical charge as they rapidly flap their wings; when they land on flowers, this charge helps pollen to stick to their hairs. Daniel Robert, a biologist at the University of Bristol, UK, knew that such electrical interactions would temporarily change the electrical status of the flowers — but he did not know whether bumblebees were picking up on this.