Paleontology in Wyoming

Paleontology in Wyoming refers to paleontological research occurring within or conducted by people from the U.S. state of Wyoming. The fossil record of Wyoming spans from the Precambrian to recent deposits. There are a large number of different fossil sites spread throughout the state. Wyoming is such a spectacular source of fossils that author Marian Murray noted in 1974 that "[e]ven today, it is the expected thing that any great museum will send its representatives to Wyoming as often as possible." Murray has also written that nearly every major vertebrate paleontologist in United States history has collected fossils in Wyoming. Wyoming is a major source of dinosaur fossils. Wyoming's dinosaur fossils are curated by museums located all over the planet.

During the Precambrian, Wyoming was covered by a shallow sea inhabited by stromatolite-forming bacteria. This sea remained in place during the early Paleozoic era and would come to be inhabited by creatures like brachiopods, ostracoderms, and trilobites. During the Silurian, the sea withdrew from Wyoming and there is a gap in the local rock record. During the Devonian the sea returned to the state and remained until the Permian when it started to withdraw once more. By the Triassic the state had become a coastal plain inhabited by dinosaurs whose footprints would later fossilize. By the Jurassic, the state was covered in sand dunes. The Western Interior Seaway submerged much of the state during the Late Cretaceous.

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