ENVIRONMENT
CORAL REEFS 2016 saw some s study of coral, i
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coral polyp on its own can measure just a few millimetres in size, but when it joins with others to form a colony, and the colony joins with other species to make a reef, those tiny polyps create one of the largest structures on Earth. It’s thought that coral reef contain 25 per cent of our planet’s biodiversity but cover just 0.2 per cent of its surface! There are two types: hard and soft. The ha corals are the reef architects – they secrete a hard, slow-growing skeleton of calcium carbonate that fuses together over time to create the giant, natural barriers. Soft cor secrete skeletons that aren’t as tough, bu still play a key part in reef growth and he The corals that grow in the shallows n super clear water, as light is essential fo growth. Their tissues contain tiny alga called zooxanthellae that photosynth provide the coral with food. The alga the coral its tropical, vibrant hue, tu reef into a riot of submarine colour. Deep-water corals don’t rely on s algae for food because they live in instead they catch their own. Cor surprising method of predation individual polyp in a colony has called nematocysts that are trig Depending on the species, the deliver a powerful and somet allowing the coral to take dow With everything in delica reefs that live near land ofte
1. Clear water Crystal-clear water helps corals thrive, as their symbiotic algae have plenty of sunlight to photosynthesise.
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2. Stony corals The reef builders – hard calcium carbonate skeletons build up over time to form huge reef structures.
026 | How It Works
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