Paleontology in Arizona

rdf:langString Paleontology in Arizona

rdf:langString Paleontology in Arizona refers to paleontological research occurring within or conducted by people from the U.S. state of Arizona. The fossil record of Arizona dates to the Precambrian. During the Precambrian, Arizona was home to a shallow sea which was home to jellyfish and stromatolite-forming bacteria. This sea was still in place during the Cambrian period of the Paleozoic era and was home to brachiopods and trilobites, but it withdrew during the Ordovician and Silurian. The sea returned during the Devonian and was home to brachiopods, corals, and fishes. Sea levels began to rise and fall during the Carboniferous, leaving most of the state a richly vegetated coastal plain during the low spells. During the Permian, Arizona was richly vegetated but was submerged by seawater late in the period. During the Triassic, Arizona was home to a rich forest home to dinosaurs and early relatives of mammals. Jurassic Arizona had a drier climate and was covered by sand dunes where dinosaurs left behind footprints. During the Cretaceous, part of eastern portions of the state were covered by the Western Interior Seaway, home to marine reptiles, including plesiosaurs and turtles. Most of Arizona was dry land during the Cenozoic era when the state was inhabited by wildlife including camels, horses, mastodons, and giant ground sloths. Local Native Americans devised myths to explain fossils. By the mid-19th century the state's fossils had already come to the attention of trained scientists. Major local finds include the Petrified Forest, Permian fossil footprints, and fossil pterosaur footprints. The Triassic tree Araucarioxylon arizonicum is the Arizona state fossil.