coral: Quick Facts

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Last updated

Nov. 8, 2026

News •

Scientists detect ‘pregnant’ coral using ultrasound device • Nov. 6, 2026, 12:47 PM ET (Popular Science)

Better together? Coral fusion could throw bleached reefs a lifeline • Oct. 15, 2026, 3:20 PM ET (Phys.org)

Photos and Videos

Fish (centre) in brain coral.

Illustration showing a cross section of a coral polyp with labeled parts including tentacles with nematocysts, mouth, zooxanthellae, living tissue linking polyps, gastrovascular cavity, skeleton, and limestone calice. An inset details a nematocyst within a tentacle.

Stony coral (Diploria).

Staghorn coral (genus Acropora).

Colorful coral reef at Shark Reef, Ras Muhammad National Park, with many small orange fish and a few bright yellow fish swimming among diverse coral formations.

A bright orange starfish rests on top of bleached coral in a coral reef, with various fish and yellow coral visible in the background off the coast of Costa Rica.

Figure 34: (Bottom) Colony of coral animals Astrangia danae (magnified about 1.7X).

Learn how non-mobile male and female corals reproduce by releasing gametes that form planulae

Learn how the sweeping motions of coral cilia draw nutrients inward and expel wastes away from the coral

Unique behaviors of gorgonians and trumpetfish

Learn how climate change affects the coral reefs

What causes coral bleaching on the Great Barrier Reef?

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Topics

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Key People

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Christian Gottfried Ehrenberg

German biologist

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Otto Heinrich Schindewolf

German paleontologist

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William Lonsdale

British geologist

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Animal Group Names