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.
Paul Sikkel and reggae star Amlak Tafari discuss the recent controversy of naming a parasite after Bob Marley.
A tiny flying drone has captured images of 300-year-old coral surrounding an island that is part of American Samoa. The new technique could be used to map the world's reefs.
The amazing underwater images will help researchers measure the health of coral reefs, including the Great Barrier Reef.
The table coral is common across the Indo-Pacific Ocean, but rarely appears around Hawaii. Marine biologists have now discovered a colony off the coast of Oahu for the first time.
This stunning wallpaper shows Biscayne National Park in Florida. Biscayne protects a rare combination of aquamarine waters, emerald islands, and fish-bejeweled coral reefs.
Clownfish do a wiggle dance inside sea anemones, circulating oxygen-rich seawater to the anemones to help them breathe.
Most of the world's coral reefs could be in big trouble by the end of the century, or much sooner, a new report warns.