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Partially bleached

Many corals and other marine animals contain dinoflagellate symbionts
that provide nutrition to the host from photosynthesis. These symbionts
can be expelled from the host following exposure to elevated
temperature or other stressors, resulting in a pale appearance or
“bleaching.” This partially bleached soft coral was observed in
relatively deep waters (50 ft) during an August trip to the Red Sea.
(Photo by Ann Tarrant, Woods Hole Oceanographic Institution)