What’s in a name?
Coral comes from a word meaning red. It was first used to describe the red coral of the Mediterranean.

Animals – not plants!
Believe it or not, corals are animals like jellyfish and anemones. Corals are made up of hundreds of tiny animals, called polyps, all living together in a colony. Polyps look a bit like an upside-down jellyfish, with a cup-like body and tentacles. Their tentacles contain stinging cells that help them catch food and protect their border.

Reef builders
Coral reefs are formed by the most common type of coral; hard coral. Hard corals use seawater to create a limestone skeleton. As the colony grows, so too does its skeleton and the coral reef.

Indoor plants
Hard corals get energy to build reefs from tiny plants living inside their cells. These plants, called zooxanthellae, use sunlight to make the food.

Split or spawn?
Coral polyps can reproduce in two ways; by dividing in two or by a process called ‘spawning’. Once a year, millions of sperm and eggs are released at the same time. New polyps are formed which then settle on the reef to build new coral colonies.

On the softer side
Not all corals are hard. Soft corals lack the hard limestone skeleton of hard corals and are instead supported by calcium rods called sclerites.