Fossil shark tooth (Squalicorax pristodontus). Example of the tooth of this Late Cretaceous (100-75 mya) Crow Shark. The serrated broad shape of the t

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Fossil shark tooth (Squalicorax pristodontus). Example of the tooth of this Late Cretaceous (100-75 mya) Crow Shark. The serrated broad shape of the tooth and some fossil evidence indicates a broad-spectrum diet of marine animals, bony fish and turtles. There is also some evidence of them scavenging the bodies of large dinosaurs that ended up in the sea. Sharks first evolved in the Palaeozoic era (570-245 million years ago). Shark's skeletons are formed of cartilage, a less durable material than bone, consequently there are few fossils of prehistoric sharks. Their teeth are made of a bone-like, enamel-coated substance that is more readily fossilised.

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Size: 2709px × 4064px
Photo credit: © GEOFF KIDD/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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