The oriental hornet has built-in "solar cells" that generate electricity from sunlight—a first in the animal kingdom, according to a new study.

Scientists already knew that the hornet species, for unknown reasons, produced electricity inside its exoskeleton, according to study leader Marian Plotkin of Tel-Aviv University.

Plotkin's late mentor Jacob Ishay made the discovery after observing that the insect is active when the sun is most intense—unusual for hornets.