|
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. ==Prehistory== No Precambrian fossils are known from Kansas, so the state's fossil record does not begin until the Paleozoic era.〔 Kansas From the Cambrian to the Devonian, Kansas was covered by a shallow sea.〔 The Cambrian life of Kansas left behind few fossils.〔 The state's sea levels began to fluctuate during the Carboniferous period.〔 While the state was still covered by the sea, it was home to a rich variety of marine invertebrates.〔 During the later half of the Carboniferous, the Pennsylvanian, nautiloids could be found in Franklin County.〔 Other kinds of marine invertebrates could be found in Anderson County.〔 Paleoniscid fishes swam in the waterways of Douglas County. Some of their fossils have preserved the fishes' soft parts.〔 Fish fossils of this age were also preserved in Anderson County.〔 During the drier intervals Kansas was home to great coastal swamps with a rich flora included ferns and scale trees. These swamps were responsible for leaving behind great coal deposits.〔 The local flora also left behind remains that would later fossilize in what are now southern Labette County and Montgomery County.〔 The plant ''Walchia'' grew in Anderson County, although its fossils are rare.〔 The contemporary terrestrial environments of Kansas were home to invertebrates like scorpions.〔 They were also home to amphibians and early reptiles.〔 Such contemporary tetrapods left behind footprints in Kansas that would later fossilize.〔 Among these were tracks of the ichnogenus ''Limnopus''.〔 Other fossils from this time period include ''Wakarusopus'' tracks left behind in Douglas County by a colossal amphibian that would have weighed several hundred pounds in life.〔 Pennsylvanian amphibian remains were also preserved in Anderson County.〔 Primitive reptiles left behind remains that were preserved in Anderson County, near the town of Garnett.〔 Most of the Permian rocks in Kansas were deposited in marine environments.〔 This setting was home to algae, brachiopods, bryozoans, fusulinids, ostracods, pelecypods, and trilobites.〔 The brachiopod genus ''Chonotes'' was common here.〔 On land, the area around Elmo in Dickinson County was home to more than ten thousand species of insects. These lived among a flora that included conifers which left behind fossils in the Garnett region.〔 For the last 70 million years of the Cretaceous period, Kansas was covered by a shallow sea.〔 This body of water is known as the Western Interior Sea.〔 The seafloor was smooth and probably never submerged by more than 600 feet of water. A great diversity of invertebrates flourished both on the bottom and in the water column. Examples include ammonites, giant clams, crinoids, rudists, and squid. Vertebrate life included bony fishes, mosasaurs, plesiosaurs, sharks, and turtles.〔 Carcasses of dinosaurs like ''Niobrarasaurus coleii'' were occasionally preserved after drifting hundreds of miles out into the Seaway.〔 Cretaceous plants left behind fossil leaves in Ellsworth County.〔 Flying above the waters of the Seaway was the great pterosaur ''Pteranodon'', which may have migrated across the sea.〔 During the Tertiary, Kansas was a savannah subjected to greater rainfall and a more moderate climate. Later in the Cenozoic, during the Quaternary, glaciers intruded southward into the northeastern part of the state, although they stayed only briefly. Much of Quaternary Kansas was covered in coniferous forests and savannahs. These environments were home to creatures like camels, saber-teeth, mammoths, and mastodons.〔 Other examples of Pleistocene life in Kansas include bison, horses, and peccaries. These left behind fossils in the western half of the state.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Paleontology in Kansas」の詳細全文を読む スポンサード リンク
|