Corals are tiny animals that live in large communities made up of individual polyps that secrete a calcium carbonate substance that hardens and builds up to form the reef structure over time. There are different types of corals, such as brain corals and fan corals, that form different types of structures. The coral polyps live symbiotically with algae that provides them with their food. Disease, temperature extremes and pollution can cause corals to expel the algae, leaving only the white calcium carbonate skeleton behind, an event called coral bleaching. Coral bleaching is a worry with global warming heating up the oceans and carbon dioxide causing the oceans to acidify. Coral reefs are important ecosystems because they support larger communities of fish, mollusks, crustaceans and other sea creatures.
Latest about coral reefs
Every year, dozens of female hammerhead sharks mysteriously convene in French Polynesia under the full moon
Every austral summer, Rangiroa and Tikehau atolls in French Polynesia host a mysterious assembly of female great hammerhead sharks — a critically endangered and typically solitary species.
Florida waters now 'bona fide bathtub conditions' as heat dome engulfs state
The unprecedented water temperatures — reaching up to 95 degrees Fahrenheit in some places — could intensify storms and hurricanes in the Sunshine State.
What Is Coral Bleaching?
Nature's red flag is the eerie white glow of one of the ocean's most biologically rich ecosystems.
Video reveals baby steps of newly hatched ‘walking’ sharks
Epaulette sharks can use their fins to "walk" underwater and even on dry land.
Red Sea dolphins slather their skin in coral mucus, because nature is wonderfully gross
Young dolphins seem to learn this skin care routine from their elders.
'Pile of rope' on a Texas beach is a weird, real-life sea creature
Frequently mistaken for discarded piles of beach trash, ropelike sea whips are a type of colorful coastal coral.
Bubbling carbon dioxide vent discovered on the seafloor off the Philippines
Scientists came across a bubbling hotspot of carbon dioxide by chance.
We Finally Know Why Florida's Coral Reefs Are Dying, and It's Not Just Climate Change
Hot water is killing Florida's coral reefs. But it's not the only factor bleaching them white.
