First Animals

Snail shell creates blue iridescence with mineral

Mollusk uses calcium compound to shine, possibly as defense

limpet

INTO THE BLUE  The bright patterns on a hard-shelled mollusk may mimic those of a shell-free, poisonous snail. 

Andy.Cowley/Wikimedia Commons (CC BY-SA 1.0)

By Vijaysree Venkatraman

- More than 2 years ago

Taking a trick from birds and butterflies, a mollusk shines blue using intricate structures that allow selective reflection of light.