Ammonite shell. Coloured X-ray of a fossil ammonite showing the spiral shell with its many chambers. Ammonites are a type of extinct cephalopod mollus

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Ammonite shell. Coloured X-ray of a fossil ammonite showing the spiral shell with its many chambers. Ammonites are a type of extinct cephalopod mollusc, resembling a squid-like animal within a coiled shell. The many chambered shell protected the delicate organs of the mollusc, and was also used for buoyancy when some of the chambers were pumped full of air. Ammonites lived from the Devonian period (approximately 400 million years ago) to the end of the Cretaceous period (64 million years ago).

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Size: 4340px × 3443px
Photo credit: © D. ROBERTS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -ray, ammonite, animal, animals, fossil, fossils, helical, helix, invertebrate, invertebrates, nature, palaeontology, paleontology, shell, spiral, xray