Bioluminescence is light created by living organisms and it can create the most fantastic displays. It includes ‘phosphorescence’ created by marine creatures and seen on the surface of the sea at night, the light of fireflies and the faint but eerie glow of some fungi. The light is produced chemically for many different reasons: to attract attention, to frighten enemies, to disguise what you really are, or – in the depths of the sea – to provide your own ‘headlights’ to search out prey.

Source:

“BBC Nature – Bioluminescence Videos, News and Facts.” BBC – Homepage. Web. 12 Nov. 2011. <http://www.bbc.co.uk/nature/adaptations/Bioluminescence>.