Fossil coral. Light micrograph of a thin cut of rock containing fossilized rugose coral. This species, now extinct, lived in tropical seas during the

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Fossil coral. Light micrograph of a thin cut of rock containing fossilized rugose coral. This species, now extinct, lived in tropical seas during the lower Carboniferous period around 350 million years ago. Seen here is the remains of a single polyp's skeleton. Corals are colonial marine organisms that live in shallow seas. They secrete an external skeleton of calcium carbonate extracted from the water. Over time, these build up into vast coral reefs, each new inhabitant building on the empty skeletons of its ancestors. Object size: 5 mm.

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Size: 4781px × 3655px
Photo credit: © ALFRED PASIEKA/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: animal, animals, caledonia, coral, evidence, fauna, fossil, fossilised, fossilized, fossils, invertebrate, invertebrates, lonsdaleia, palaeontology, paleontology, polyp, preserved, rugose