Fluorescent Corals

Corals are marine invertebrates in the class Anthozoa of phylum Cnidaria. They typically live in compact colonies of many identical individual... more

by Miroslava Jurcik

Title

Fluorescent Corals

Artist

Miroslava Jurcik

Medium

Photograph

Description

Corals are marine invertebrates in the class Anthozoa of phylum Cnidaria. They typically live in compact colonies of many identical individual polyps. The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.
Why some corals fluoresce is not fully known and is a subject of much study. In particular, shallow water reef-building corals that fluoresce seem to be more resistant to coral bleaching than other corals, and the higher the density of flurorescent pigments, the more likely to resist. This enables them to better protect the zooxanthellae that help sustain them.
It’s one of the ocean’s most beautiful and striking mysteries: Why do corals fluoresce?
Jörg Wiedenmann, a coral reef scientist at University of Southampton, had previously found that the pink and purple fluorescence in shallow waters act as a kind of sunscreen. The fluorescent pigments absorb damaging wavelengths of light and emit it as pink or purple light, protecting the single-celled organisms called zooxanthellae that live symbiotically inside coral. Zooxanthellae are photosynthetic and they provide the coral with food in exchange for shelter. However that does not explain why are they fluorescent in deeper waters.
This picture was taken at Sealife Sydney Aquarium under the South coast Australia display !

Uploaded

August 25th, 2017