Light-sensitive stinging cells

Researchers studying hydra - tiny sea-creatures related to corals and jellyfish - have made the surprising discovery that their stinging cells, called cnidocytes, are sensitive to light.

Although it's known that these cells sting in response to touch and taste, this is the first time they've been linked to light.

The scientists, led by Todd Oakley, found that the stingy cells contains opsins - light-sensitive proteins that are used widely in light-sensing organs and eyes across the animal kingdom.

Oakley thinks that his findings may help to shed light on the evolution of eyes - well, we'll see...