Reefs have existed since at least the Cambrian, although the familiar coral-dominated, reefs of today are a much later arrival. A coral reef is much more than old rock lying on the sea bed. An intricate structure, complex set of relationships and distinct zones (reef top, reef sides, debris piles around the base) offer myriad places for animals to live and hide, which leads to incredible diversity.
Did you know?
Australia's Great Barrier Reef is larger than the Great Wall of China and is visible from space.
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Regeneration
Constant destruction and regeneration is just part of life for the corals of the reef.
Constant destruction and regeneration is just part of life for the corals of the reef.
Reef record
The Great Barrier Reef is over 2000 km long.
The Great Barrier Reef is over 2000 km long.
Why the shark needs the sponge
A turtle leads Chris to the secret of the coral reef – the sponge.
A turtle leads Chris to the secret of the coral reef – the sponge. These are surely one of the weirdest animals on the planet but thanks to the way that they feed, the reef and everything on it, right up to the sharks, is able to glean enough nutrients from the clear seawater.
Colourless corals
Rising sea temperatures force corals to expel their pigmented algae, causing coral bleaching.
Rising sea temperatures force corals to expel their pigmented algae, causing coral bleaching.
Night and day
Corals reveal the secrets of their plant-like structures.
Corals reveal the secrets of their plant-like structures.
A reef is a rock, sandbar, or other feature lying beneath the surface of the water (80 meters or less beneath low water).
Many reefs result from abiotic processes—deposition of sand, wave erosion planing down rock outcrops, and other natural processes—but the best-known reefs are the coral reefs of tropical waters developed through biotic processes dominated by corals and calcareous algae. Artificial reefs such as shipwrecks are sometimes created to enhance physical complexity on generally featureless sand bottoms in order to attract a diverse assemblage of organisms, especially fish.
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Useful behaviours for this habitat
Ecozones where this habitat is found
Other Marine habitats
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