Green and Red fluorescent proteins in coral

[Sea_Student]

I've heard that corals can have GFP (green fluorescent proteins) and RFP (Red fluorescent proteins) and I'm wondering what the use is of the different colours? I know that the GFPs are for UV protection as it reemits UV as a lower-energy blue light, but why are RFPs red? Surely there is a reason for the red colouration.

 

[Subsea]

Dana Riddle articles on Advanced Aquaria is one source for that info.

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