What are coral reefs? Coral can be found in tropical ocean waters around the world. But how much do you know about reefs and the tiny animals—polyps—that build them? Learn all about coral and why warming waters threaten the future of the reef ecosystem.
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Read more about Corals here:
https://on.natgeo.com/2Uo3q41

Coral Reefs 101 | National Geographic
https://youtu.be/ZiULxLLP32s

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