Ammonite. Cross-section of a fossilised ammonite (sub-class Ammonoidea;class Cephalopoda), clearly showing the chambers within the shell. This ammonit

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Ammonite. Cross-section of a fossilised ammonite (sub-class Ammonoidea;class Cephalopoda), clearly showing the chambers within the shell. This ammonite has been subject to mineralisation, the most common fossilisation process. During this process the original shell was completely replaced by minerals in a saturated solution in the surrounding sediment. These ammonites were sea creatures which existed from the Devonian period (400 million years ago) until becoming extinct at about the same time as the dinosaurs at the end of the Cretaceous period (about 65 million years ago). This fossil was found in Germany.

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Size: 3543px × 2636px
Photo credit: © GEOFF TOMPKINSON/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: ammonite, ammonoidea, animal, animals, cephalopoda, fossil, fossils, invertebrate, invertebrates, palaeontology, paleontology, spiral