Over the past decade, scientists have found evidence for biofluorescence in more than 200 species of fish, including two species of catsharks, and marine turtles. 

Biofluorescence is the absorption and reemission of light from living organisms. Fluorescent organisms have proteins built into their skin or other tissues that absorb energy from sunlight and reemit it as a different color.

With biofluorescence, blue wavelengths of light hit the surface of an animal and are then emitted as a different color, usually vivid greens, oranges, and reds. This is different from bioluminescence, where animals such as jellyfish or fireflies generate their own light through a chemical reaction.

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