Coral and Coral Reef

Coral reefs around the world have similar plants and animals. This means that the same families and genera tend to be present, although the actual species may be different. They have the highest biodiversity and greatest ecological complexity of any marine ecosystem. Many coral-reef organisms have established balanced, mutualistic relationships that help sustain a great richness of species and a tremendous complexity of ecological interactions. Coral reefs develop under environmental conditions characterized by a restricted supply of nutrients, yet maintain a high rate of productivity because of their efficient use of nutrients.

Some ecologists believe that coral reefs maintain high biodiversity as a response to a stable but periodically disturbed environment that allows for the accumulation of species over time. The most competitive species are prevented from dominating the ecosystem, while small-scale disturbances maintain a shifting mosaic of relatively young habitats for colonization by less competitive species. Natural disturbances to which coral reefs must typically adapt include intense windstorms such as hurricanes, events of sediment deposition or volcanism, unusually low tides, short-term temperature extremes, and the population dynamics of reef species.