Tortoise fossil. This is a freshwater tortoise from the Trionix genus. This genus is still extant today, but this specimen is from a rock formation da

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Tortoise fossil. This is a freshwater tortoise from the Trionix genus. This genus is still extant today, but this specimen is from a rock formation dating from the Eocene (56 to 34 million years ago). Fossils appear as rock slowly forms around objects buried in mud. As the rock forms, the shape and anatomy of buried animals and plants can be preserved. This fossil is from the Green River Formation, Wyoming, USA.

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Size: 3406px × 5127px
Photo credit: © CHRIS HELLIER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

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