Scientists discover why two shark species emit green glow

Previously undiscovered group of molecules found to be behind phenomenon

The secret behind the eerie glow of two shark species has been revealed in a study which sheds light on the origin and possible advantages of their fluorescent green bodies.

Chain catsharks and swell sharks are deep-dwelling and live in the western Atlantic and eastern Pacific respectively, where they hide among rocks and rubble. While at first glance they appear to be in various shades of brown, recent studies have shown that under blue light they glow green. Crucially, only blue light penetrates the depths of the ocean.