Coral reef
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A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony co
Brain coral spawning
Biodiversity in a coral reef
Ancient coral reefs
Fringing reef at Eilat at the southern tip of Israel
Great Barrier Reef
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The Great Barrier Reef is the world's largest coral reef system, composed of over 2,900 individual reefs and 900 islands stretching for over 2,300 kilometres over an area of approximately 344,400 squa
Coral reef
…nature of the substrate on which they rest, and the history of the change in sea level relative to that substrate. The approximately 20,000-year-old Great Barrier Reef offers an example of how coral reefs formed on continental shelves. Sea level was then 120 m (390 ft) lower than in the 21st century. As sea level rose…
Image of part of the Great Barrier Reef adjacent to Queensland, taken from the International Space Station
Aerial photography
Heron Island, a coral cay in the southern Great Barrier Reef
Aerial view of Arlington Reef