Can fruit fly larvae sense electric fields?

Researchers have found that besides sharks, bees and platypus, even fruit fly larvae can sense electric fields and navigate toward the negative electric potential using a small set of sensory neurons in their head. Researchers at the University of California at Santa Barbara immersed a fruit fly larva in an electric field and they found the larva reoriented itself and began moving toward the negative electrode. They found the neurons crucial to electroreception were located on either side of the larva’s head. Exposing the head segment to an electric field under the microscope confirmed their initial finding. They found that only a single neuron in this cluster responded to the electric field. The neuron was inhibited when the electrode was in front of the head, and activated when the electrode was behind, triggering the larva to reorient itself. By systematically eliminating confounding factors, the researchers confirmed that the larvae were responding to the electric field itself. And it was specifically the neurons in their head that detected the electric field, its strength and orientation.