Bees use a flower’s colour, shape and scent to find the best nectar. But they also use electricity, say scientists at the University of Bristol in England. Flowers naturally have a negative electric charge. Bees, which have a positive charge, may be able to feel the flower’s electrical force when the static bristles their body hairs. The researchers’ experiments reveal that, when a bee lands on a flower, it temporarily alters the flower’s charge, a change that lasts even after the bee departs. By sensing that voltage change, a bee might be able to detect whether another pollinator has just visited a flower and plundered its nectar. –SF
Testing the bees
How do bees find flowers?
To find out whether bees really do use electric fields to find food, the researchers created artificial flowers. Some were positively charged and contained a bee-pleasing, sugary drink, and the others had no charge and a bitter drink. The bees quickly learned to find the sweet rewards of the positively charged flowers – with 81 per cent accuracy. But when the researchers turned off the electricity, the bees were totally clueless.
How do bees choose flowers?
To find out if bees can use not only the presence of a charge, but also differently shaped electrical fields to forage, researchers gave sweet flowers a negative charge in the centre and a positive voltage at the edges (below, left), and bitter flowers a uniform voltage (below, right). Bees were able to sense the voltage patterns with 70 per cent accuracy to stay away from the bitter flowers and opt for the sweet ones.