Each individual polyp within the colony builds a skeleton of calcium carbonate to form these hard rounded formations that may last centuries.

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Each individual poly within the colony builds a skeleton of calcium carbonate to form these hard rounded formations that may last centuries. Ocean acidification and warming seas threatens them

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Size: 6000px × 4000px
Location: Zanzibar, Tanzania
Photo credit: © Nick Greaves / Alamy / Afripics
License: Licensed
Model Released: No

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