Paleontology in Wyoming

Paleontology in Wyoming includes research into the prehistoric life of the U.S. state of Wyoming as well as investigations conducted by Wyomingite researchers and institutions into ancient life occurring elsewhere.

The fossil record of the US state of Wyoming spans from the Precambrian to recent deposits. Many fossil sites are spread throughout the state.^[1] 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."^[2] Murray has also written that nearly every major vertebrate paleontologist in United States history has collected fossils in Wyoming.^[1] Wyoming is a major source of dinosaur fossils.^[1] Wyoming's dinosaur fossils are curated by museums located all over the planet.^[2]

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.

During the early part of the Cenozoic, Wyoming was home to massive lakes inhabited by Knightia fish and dense forests. On land the state would come to be inhabited by camelids, carnivorans, creodonts, the seven foot tall flightless bird Gastornis, proboscideans, equids, primates, rodents, and Uintatherium. During the Ice Age, Wyoming was subject to glacial activity. Local Native Americans have known about fossils for thousands of years and have both applied them to practical purposes and devised myths to explain them. Wyoming first became a hotspot for dinosaur research in the 1870s with the discovery of the dinosaurs preserved in the Morrison Formation. By the early 20th century, hundreds of tons of dinosaur fossils had been excavated from Wyoming. The Eocene fish Knightia is the Wyoming state fossil. Triceratops is the state dinosaur of Wyoming.