Paleontology in Colorado

Paleontology in Colorado refers to paleontological research occurring within or conducted by people from the U.S. state of Colorado. The geologic column of Colorado spans about one third of Earth's history. Fossils can be found almost everywhere in the state but are not evenly distributed among all the ages of the state's rocks.^[1] During the early Paleozoic, Colorado was covered by a warm shallow sea that would come to be home to creatures like brachiopods, conodonts, ostracoderms, sharks and trilobites. This sea withdrew from the state between the Silurian and early Devonian leaving a gap in the local rock record. It returned during the Carboniferous. Areas of the state not submerged were richly vegetated and inhabited by amphibians that left behind footprints that would later fossilize. During the Permian, the sea withdrew and alluvial fans and sand dunes spread across the state. Many trace fossils are known from these deposits.

The sea returned during the Triassic, while exposed areas were a richly vegetated coastal plain that was home to dinosaurs. Colorado was again submerged by a sea during the Cretaceous period that was home to plesiosaurs up to 70 feet long. During the early part of the Cenozoic era, rainforests grew in Colorado. Later, another rich flora and fauna would come to be preserved in the Florissant beds, where both rhinoceroses and uintatheres lived. More recently the state's modern prairies began to form and the state was home to creatures like bison, camels, horses, and mammoths. Local Native Americans have devised myths to explain local fossil bones and dinosaur footprints. By the late 19th century, local fossils had attracted the attention of formally trained scientists. Major finds include the Late Jurassic dinosaurs of the Morrison Formation and the Cenozoic plants and mammals of the Florissant beds. The Jurassic plated dinosaur Stegosaurus armatus is the Colorado state fossil. Stegosaurus is also the state dinosaur of Colorado.