Paleontology in Virginia refers to paleontological research occurring within or conducted by people from the U.S. state of Virginia. The geologic column in Virginia spans from the Cambrian to the Quaternary. During the early part of the Paleozoic, Virginia was covered by a warm shallow sea. This sea would come to be inhabited by creatures like brachiopods, bryozoans, corals, and nautiloids. The state was briefly out of the sea during the Ordovician, but by the Silurian it was once again submerged. During this second period of inundation the state was home to brachiopods, trilobites and entire reef systems. During the mid-to-late Carboniferous the state gradually became a swampy environment.
Paleontology in Tennessee refers to paleontological research occurring within or conducted by people from the U.S. state of Tennessee. During the early part of the Paleozoic era, Tennessee was covered by a warm, shallow sea. This sea was home to brachiopods, bryozoans, cephalopods, corals, and trilobites. Tennessee is one of the best sources of Early Devonian fossils in North America. During the mid-to-late Carboniferous, the state became a swampy environment, home to a rich variety of plants including ferns and scale trees. A gap in the local rock record spans from the Permian through the Jurassic. During the Cretaceous, the western part of the state was submerged by seawater. The local waters were home to more fossil gastropods than are known from anywhere else in the world. Mosasaurs and sea turtles also inhabited these waters. On land the state was home to dinosaurs. Western Tennessee was still under the sea during the early part of the Cenozoic. Terrestrial portions of the state were swampy. Climate cooled until the Ice Age, when the state was home to Camelops, horses, mammoths, mastodons, and giant ground sloths. The local Yuchi people told myths of giant lizard monsters that may have been inspired by fossils either local or encountered elsewhere. In 1920, after local fossils became a subject of formal scientific study, a significant discovery of a variety of Pleistocene creatures was made near Nashville. The Cretaceous bivalve Pterotrigonia thoracica is the Tennessee state fossil.
Paleontology in New Jersey refers to paleontological research in the U.S. state of New Jersey. The state is especially rich in marine deposits.
Paleontology in Alabama refers to paleontological research occurring within or conducted by people from the U.S. state of Alabama. Pennsylvanian plant fossils are common, especially around coal mines. During the early Paleozoic, Alabama was at least partially covered by a sea that would end up being home to creatures including brachiopods, bryozoans, corals, and graptolites. During the Devonian the local seas deepened and local wildlife became scarce due to their decreasing oxygen levels.
Paleontology in Mississippi refers to paleontological research occurring within or conducted by people from the U.S. state of Mississippi. The oldest rocks in Mississippi date back to the Late Devonian. At the time, the northeastern part of the state was covered in a sea where brachiopods, crinoids, and trilobites lived. Remains of contemporary local plants also ended up preserved in this environment. During the Late Carboniferous, Mississippi became part of a richly-vegetated coastal plain environment. There are no rocks dating to the Permian, Triassic, or Jurassic in the state. However, during the Cretaceous, evidence suggests that the state was covered by a sea home to cephalopods, mosasaurs and sharks. Local trees left behind petrified wood and amber. By the Cenozoic, only the southern half of the state was covered in seawater, where the early whale Basilosaurus lived. On land, trees that were home to some of the earliest known primates left behind petrified wood. For the remainder of the Cenozoic, the state's climate cooled. Many fossils have been serendipitously discovered in the state by people looking for fossil fuels. Significant fossil finds in Mississippi include some of the oldest known primate fossils. The Eocene whales Basilosaurus cetoides and Zygorhiza kochii are the Mississippi state fossils.
Paleontology in Arkansas refers to paleontological research occurring within or conducted by people from the U.S. state of Arkansas. The fossil record of Arkansas spans from the Ordovician to the Eocene. Nearly all of the state's fossils have come from ancient invertebrate life. During the early Paleozoic, much of Arkansas was covered by seawater. This sea would come to be home to creatures including Archimedes, brachiopods, and conodonts. This sea would begin its withdrawal during the Carboniferous, and by the Permian the entire state was dry land. Terrestrial conditions continued into the Triassic, but during the Jurassic, another sea encroached into the state's southern half. During the Cretaceous the state was still covered by seawater and home to marine invertebrates such as Belemnitella. On land the state was home to long necked sauropod dinosaurs, who left behind footprints and ostrich dinosaurs such as Arkansaurus.
Paleontology in Missouri refers to paleontological research occurring within or conducted by people from the U.S. state of Missouri. The geologic column of Missouri spans all of geologic history from the Precambrian to present with the exception of the Permian, Triassic, and Jurassic. Brachiopods are probably the most common fossils in Missouri.
Paleontology in Minnesota refers to paleontological research occurring within or conducted by people from the U.S. state of Minnesota. The geologic record of Minnesota spans from Precambrian to recent with the exceptions of major gaps including the Silurian period, the interval from the Middle to Upper Devonian to the Cretaceous, and the Cenozoic. During the Precambrian, Minnesota was covered by an ocean where local bacteria ended up forming banded iron formations and stromatolites. During the early part of the Paleozoic era southern Minnesota was covered by a shallow tropical sea that would come to be home to creatures like brachiopods, bryozoans, massive cephalopods, corals, crinoids, graptolites, and trilobites. The sea withdrew from the state during the Silurian, but returned during the Devonian. However, the rest of the Paleozoic is missing from the local rock record. The Triassic is also missing from the local rock record and Jurassic deposits, while present, lack fossils. Another sea entered the state during the Cretaceous period, this one inhabited by creatures like ammonites and sawfish. Duckbilled dinosaurs roamed the land. The Paleogene and Neogene periods of the ensuing Cenozoic era are also missing from the local rock record, but during the Ice Age evidence points to glacial activity in the state. Woolly mammoths, mastodons, and musk oxen inhabited Minnesota at the time. Local Native Americans interpreted such remains as the bones of the water monster Unktehi. They also told myths about thunder birds that may have been based on Ice Age bird fossils. By the early 19th century, the state's fossil had already attracted the attention of formally trained scientists. Early research included the Cretaceous plant discoveries made by Leo Lesquereux.
Paleontology in North Dakota refers to paleontological research occurring within or conducted by people from the U.S. state of North Dakota. During the early Paleozoic era most of North Dakota was covered by a sea home to brachiopods, corals, and fishes. The sea briefly left during the Silurian, but soon returned, until once more starting to withdraw during the Permian. By the Triassic some areas of the state were still under shallow seawater, but others were dry and hot. During the Jurassic subtropical forests covered the state. North Dakota was always at least partially under seawater during the Cretaceous. On land Sequoia grew. Later in the Cenozoic the local seas dried up and were replaced by subtropical swamps. Climate gradually cooled until the Ice Age, when glaciers entered the area and mammoths and mastodons roamed the local woodlands.
Paleontology in South Dakota refers to paleontological research occurring within or conducted by people from the U.S. state of South Dakota. South Dakota is an excellent source of fossils as finds have been widespread throughout the state. During the early Paleozoic era South Dakota was submerged by a shallow sea that would come to be home to creatures like brachiopods, cephalopods, corals, and ostracoderms. Local sea levels rose and fall during the Carboniferous and the sea left completely during the Permian. During the Triassic, the state became a coastal plain, but by the Jurassic it was under a sea where ammonites lived. Cretaceous South Dakota was also covered by a sea that was home to mosasaurs. The sea remained in place after the start of the Cenozoic before giving way to a terrestrial mammal fauna including the camel Poebrotherium, three-toed horses, rhinoceroses, saber-toothed cat, and titanotheres. During the Ice Age glaciers entered the state, which was home to mammoths and mastodons. Local Native Americans interpreted fossils as the remains of the water monster Unktehi and used bits of Baculites shells in magic rituals to summon buffalo herds. Local fossils came to the attention of formally trained scientists with the Lewis and Clark Expedition. The Cretaceous horned dinosaur Triceratops horridus is the South Dakota state fossil.
Paleontology in Nebraska refers to paleontological research occurring within or conducted by people from the U.S. state of Nebraska. Nebraska is world-famous as a source of fossils. During the early Paleozoic, Nebraska was covered by a shallow sea that was probably home to creatures like brachiopods, corals, and trilobites. During the Carboniferous, a swampy system of river deltas expanded westward across the state. During the Permian period, the state continued to be mostly dry land. The Triassic and Jurassic are missing from the local rock record, but evidence suggests that during the Cretaceous the state was covered by the Western Interior Seaway, where ammonites, fish, sea turtles, and plesiosaurs swam. The coasts of this sea were home to flowers and dinosaurs. During the early Cenozoic, the sea withdrew and the state was home to mammals like camels and rhinoceros. Ice Age Nebraska was subject to glacial activity and home to creatures like the giant bear Arctodus, horses, mammoths, mastodon, shovel-tusked proboscideans, and Saber-toothed cats. Local Native Americans devised mythical explanations for fossils like attributing them to water monsters killed by their enemies, the thunderbirds. After formally trained scientists began investigating local fossils, major finds like the Agate Springs mammal bone beds occurred. The Pleistocene mammoths Mammuthus primigenius, Mammuthus columbi, and Mammuthus imperator are the Nebraska state fossils.
Paleontology in Kansas refers to paleontological research occurring within or conducted by people from the U.S. state of Kansas. Kansas has been the source of some of the most spectacular fossil discoveries in US history. The fossil record of Kansas spans from the Cambrian to the Pleistocene. From the Cambrian to the Devonian, Kansas was covered by a shallow sea. During the ensuing Carboniferous the local sea level began to rise and fall. When sea levels were low the state was home to richly vegetated deltaic swamps where early amphibians and reptiles lived. Seas expanded across most of the state again during the Permian, but on land the state was home to thousands of different insect species. The popular pterosaur Pteranodon is best known from this state. During the early part of the Cenozoic era Kansas became a savannah environment. Later, during the Ice Age, glaciers briefly entered the state, which was home to camels, mammoths, mastodons, and saber-teeth. Local fossils may have inspired Native Americans to regard some local hills as the homes of sacred spirit animals. Major scientific discoveries in Kansas included the pterosaur Pteranodon and a fossil of the fish Xiphactinus that died in the act of swallowing another fish.
Paleontology in Texas refers to paleontological research occurring within or conducted by people from the U.S. state of Texas. Author Marian Murray has said that "Texas is as big for fossils as it is for everything else." Some of the most important fossil finds in United States history have come from Texas. Fossils can be found throughout most of the state. The fossil record of Texas spans almost the entire geologic column from Precambrian to Pleistocene. Shark teeth are probably the state's most common fossil. During the early Paleozoic era Texas was covered by a sea that would later be home to creatures like brachiopods, cephalopods, graptolites, and trilobites. Little is known about the state's Devonian and early Carboniferous life. Evidence indicates that during the late Carboniferous the state was home to marine life, land plants and early reptiles. During the Permian, the seas largely shrank away, but nevertheless coral reefs formed in the state. The rest of Texas was a coastal plain inhabited by early relatives of mammals like Dimetrodon and Edaphosaurus. During the Triassic, a great river system formed in the state that was inhabited by crocodile-like phytosaurs. Little is known about Jurassic Texas, but there are fossil aquatic invertebrates of this age like ammonites in the state. During the Early Cretaceous local large sauropods and theropods left a great abundance of footprints. Later in the Cretaceous, the state was covered by the Western Interior Seaway and home to creatures like mosasaurs, plesiosaurs, and few icthyosaurs. Early Cenozoic Texas still contained areas covered in seawater where invertebrates and sharks lived. On land the state would come to be home to creatures like glyptodonts, mammoths, mastodons, saber-toothed cats, giant ground sloths, titanotheres, uintatheres, and dire wolves. Archaeological evidence suggests that local Native Americans knew about local fossils. Formally trained scientists were already investigating the state's fossils by the late 1800s. In 1938, a major dinosaur footprint find occurred near Glen Rose. Pleurocoelus was the Texas state dinosaur from 1997 to 2009, when it was replaced by Paluxysaurus jonesi after the Texan fossils once referred to the former species were reclassified to a new genus.
Paleontology in Montana refers to paleontological research occurring within or conducted by people from the U.S. state of Montana. The fossil record in Montana stretches all the way back to the Precambrian. During the Late Precambrian, western Montana was covered by a warm, shallow sea where local bacteria formed stromatolites and bottom-dwelling marine life left tracks on the sediment that would later fossilize. This sea remained in place during the early Paleozoic, although withdrew during the Silurian and Early Devonian, leaving a gap in the local rock record until its return. This sea was home to creatures including brachiopods, conodonts, crinoids, fish, and trilobites. During the Carboniferous the state was home to an unusual cartilaginous fish fauna. Later in the Paleozoic the sea began to withdraw, but with a brief return during the Permian.
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.
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. 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.
Paleontology in New Mexico refers to paleontological research occurring within or conducted by people from the U.S. state of New Mexico. The fossil record of New Mexico is exceptionally complete and spans almost the entire stratigraphic column. More than 3,300 different kinds of fossil organisms have been found in the state. Of these more than 700 of these were new to science and more than 100 of those were type species for new genera. During the early Paleozoic, southern and western New Mexico were submerged by a warm shallow sea that would come to be home to creatures including brachiopods, bryozoans, cartilaginous fishes, corals, graptolites, nautiloids, placoderms, and trilobites. During the Ordovician the state was home to algal reefs up to 300 feet high. During the Carboniferous, a richly vegetated island chain emerged from the local sea. Coral reefs formed in the state's seas while terrestrial regions of the state dried and were home to sand dunes. Local wildlife included Edaphosaurus, Ophiacodon, and Sphenacodon.
Paleontology in Idaho refers to paleontological research occurring within or conducted by people from the U.S. state of Idaho. The fossil record of Idaho spans much of the geologic column from the Precambrian onward. During the Precambrian, bacteria formed stromatolites while worms left behind trace fossils. The state was mostly covered by a shallow sea during the majority of the Paleozoic era. This sea became home to creatures like brachiopods, corals and trilobites. Idaho continued to be a largely marine environment through the Triassic and Jurassic periods of the Mesozoic era, when brachiopods, bryozoans, corals, ichthyosaurs and sharks inhabited the local waters. The eastern part of the state was dry land during the ensuing Cretaceous period when dinosaurs roamed the area and trees grew which would later form petrified wood.
The geological history of North America comprises the history of geological occurrences and emergence of life in North America during the interval of time spanning from the formation of the earth through to the emergence of humanity and the start of prehistory. At the start of the Paleozoic Era, what is now "North" America was actually in the Southern Hemisphere. Marine life flourished in the country's many seas, although terrestrial life had not yet evolved. During the latter part of the Paleozoic, seas were largely replaced by swamps home to amphibians and early reptiles. When the continents had assembled into Pangaea, drier conditions prevailed. The evolutionary precursors to mammals dominated the country until a mass extinction event ended their reign.
The Winneshiek Shale is a Middle Ordovician (Darriwilian-age) geological formation in Iowa. The formation is restricted to the Decorah crater, an impact crater near Decorah, Iowa. Despite only being discovered in 2005, the Winneshiek Shale is already renowned for the exceptional preservation of its fossils. The shale preserves a unique ecosystem, the Winneshiek biota, which is among the most remarkable Ordovician lagerstätten in the United States. Fossils include the oldest known eurypterid, Pentecopterus, as well as giant conodonts such as Iowagnathus and Archeognathus.
