Coiled and heteromorph ammonites. The heteromorph ammonite is in the background, with a planospirally coiled ammonite in the foreground. Ammonites wer

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Coiled and heteromorph ammonites. The heteromorph ammonite is in the background, with a planospirally coiled ammonite in the foreground. Ammonites were marine invertebrate molluscs that formed a spiral chambered shell, with the ammonite living in the newest and largest chamber. Shells ranged in width from under 1 centimetre to over 1 metre. Ammonites first appear in the fossil record around 400 million years ago and became extinct at the end of the Cretaceous period 65 million years ago.

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Size: 3888px × 5184px
Photo credit: © SINCLAIR STAMMERS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, 2, ammonite, animal, background, biological, biology, black, coiled, duo, evolution, evolutionary, extinct, fauna, fossil, fossilised, fossilized, fossils, heteromorph, historical, history, invertebrate, marine, mollusc, natural, nature, pair, palaeobiology, palaeontology, palaeozoology, paleontology, planospirally, prehistoric, prehistory, zoological, zoology