Credit: Nature Commun./CC-BY

Electric eels send out strong zaps to track moving prey by their electrical conductivity, enabling the eels to strike with remarkable precision.

Electric eels (Electrophorus electricus; pictured) are known to use electricity to stun their prey, and have electrical sensors (pictured in pink). To see whether the high-voltage zaps have a sensory role, Kenneth Catania at Vanderbilt University in Nashville, Tennessee, presented the eels with a twitching fish in an insulated plastic bag and a conductive rod.

The eels reacted to the mechanical signals from the moving prey, producing a strong shock and striking in the direction of the fish. But they repositioned mid-strike, capturing and attempting to feed on the rod instead, even when it moved around quickly.

This sensory system is similar to how some bats use echolocation, says Catania.

Nature Commun. 6, 8661 (2015)