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Campeloma Nebrascensis
''Campeloma nebrascensis'' is a species of extinct freshwater snail from the Maastrichtian (late Cretaceous) of North America. The species is distributed from Montana to Colorado, where extant ''Campeloma'' species live today. Etymology ''Campeloma nebrascensis'' was named after the former Territory of Nebraska, located in the United States. The name of the territory "Nebraska" came from the Omaha-Ponca word "NiNbdhaska", which means "Flatwater", in reference to the Platte river. Discovery and History Expeditions into the Territory of Louisiana had brought lots of new discoveries to American scientists in the first half of the 19th century. While expeditions such as the Lewis and Clark Expedition had made many discoveries of new plants and animals, the geology had apparently been overlooked by other explorers. By 1854, the Louisiana and other unorganized territories had been split into numerous other territories, one of them being the Territory of Nebraska. Members of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animalia
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinode ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platte River
The Platte River () is a major river in the State of Nebraska. It is about long; measured to its farthest source via its tributary, the North Platte River, it flows for over . The Platte River is a tributary of the Missouri River, which itself is a tributary of the Mississippi River which flows to the Gulf of Mexico. The Platte over most of its length is a broad, shallow, meandering stream with a sandy bottom and many islands—a braided stream. The Platte is one of the most significant tributary systems in the watershed of the Missouri, draining a large portion of the central Great Plains in Nebraska and the eastern Rocky Mountains in Colorado and Wyoming. The river valley played an important role in the westward expansion of the United States, providing the route for several major emigrant trails, including the Oregon, California, Mormon and Bozeman trails. The first Europeans to see the Platte were French explorers and fur trappers about 1714; they first called it the '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parthenogenesis
Parthenogenesis (; from the Greek grc, παρθένος, translit=parthénos, lit=virgin, label=none + grc, γένεσις, translit=génesis, lit=creation, label=none) is a natural form of asexual reproduction in which growth and development of embryos occur in a gamete (egg or sperm) without combining with another gamete (e.g., egg and sperm fusing). In animals, parthenogenesis means development of an embryo from an unfertilized Gametophyte, egg cell. In plants, parthenogenesis is a component process of apomixis. In algae, parthenogenesis can mean the development of an embryo from either an individual sperm or an individual egg. Parthenogenesis occurs naturally in some plants, algae, invertebrate animal species (including nematodes, some tardigrades, water fleas, some scorpions, aphids, some mites, some bees, some Phasmatodea and parasitic wasps) and a few vertebrates (such as some fish, amphibians, reptiles and birds). This type of reproduction has been induced artificially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viviparus
''Viviparus'', common name the river snails, is a genus of large, freshwater snails with an operculum, aquatic gastropod mollusks.Bouchet, P. (2014). Viviparus Montfort, 1810. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=154004 on 2014-11-13 They are primitive members of the clade Caenogastropoda. The old name of the genus was ''Paludina''. Distribution This genus is palaearctic in distribution, and is known from the Jurassic to the Recent. Species ''Viviparus'' belongs to the subfamily Viviparinae. Its taxonomy is currently under development and many of its species are often included in other related genera. It includes the following species: * † ''Viviparus achatinoides'' (Deshayes, 1838) * '' Viviparus acerosus'' (Bourguignat, 1862) * † '' Viviparus aitaiensis'' Jekelius, 1932 * † '' Viviparus alexandrieni'' Cobălcescu, 1883 * † '' Viviparus altecarinatus'' Brusina, 1874 * † '' Viviparus altu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hell Creek Formation
The Hell Creek Formation is an intensively studied division of mostly Upper Cretaceous and some lower Paleocene rocks in North America, named for exposures studied along Hell Creek, near Jordan, Montana. The formation stretches over portions of Montana, North Dakota, South Dakota, and Wyoming. In Montana, the Hell Creek Formation overlies the Fox Hills Formation. The site of Pompeys Pillar National Monument is a small isolated section of the Hell Creek Formation. In 1966, the Hell Creek Fossil Area was designated as a National Natural Landmark by the National Park Service. It is a series of fresh and brackish-water clays, mudstones, and sandstones deposited during the Maastrichtian and Danian (respectively, the end of the Cretaceous period and the beginning of the Paleogene) by fluvial activity in fluctuating river channels and deltas and very occasional peaty swamp deposits along the low-lying eastern continental margin fronting the late Cretaceous Western Interior Seaway. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bittium Reticulatum
''Bittium reticulatum'' is a species of sea snail, a marine gastropod mollusk in the family Cerithiidae Cerithiidae, common name the cerithiids or ceriths, is a large family of medium-sized marine gastropods in the clade Sorbeoconcha. Distribution Ceriths are found worldwide on sandy bottoms, reef flats or coral reef rock covered with sand .... Description Distribution References Cerithiidae Gastropods described in 1778 {{Cerithiidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cenozoic
The Cenozoic ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterised by the dominance of mammals, birds and flowering plants, a cooling and drying climate, and the current configuration of continents. It is the latest of three geological eras since complex life evolved, preceded by the Mesozoic and Paleozoic. It started with the Cretaceous–Paleogene extinction event, when many species, including the non-avian dinosaurs, became extinct in an event attributed by most experts to the impact of a large asteroid or other celestial body, the Chicxulub impactor. The Cenozoic is also known as the Age of Mammals because the terrestrial animals that dominated both hemispheres were mammalsthe eutherians (placentals) in the northern hemisphere and the metatherians (marsupials, now mainly restricted to Australia) in the southern hemisphere. The extinction of many groups allowed mammals and birds to greatly diversify so that l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little Missouri River (North Dakota)
The Little Missouri River is a tributary of the Missouri River, 560 miles (901 km) long, in the northern Great Plains of the United States. Rising in northeastern Wyoming, in western Crook County about 15 miles (24 km) west of Devils Tower, it flows northeastward, across a corner of southeastern Montana, and into South Dakota. In South Dakota, it flows northward through the Badlands into North Dakota, crossing the Little Missouri National Grassland and both units of Theodore Roosevelt National Park. In the north unit of the park, it turns eastward and flows into the Missouri in Dunn County at Lake Sakakawea, where it forms an arm of the reservoir 30 miles (48 km) long called Little Missouri Bay and joins the main channel of the Missouri about 25 miles (40 km) northeast of Killdeer. The highly seasonal runoff from badlands and other treeless landscapes along the Little Missouri carries heavy loads of eroded sediment downstream. The sedimentary layers, which ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lewis And Clark Expedition
The Lewis and Clark Expedition, also known as the Corps of Discovery Expedition, was the United States expedition to cross the newly acquired western portion of the country after the Louisiana Purchase. The Corps of Discovery was a select group of U.S. Army and civilian volunteers under the command of Captain Meriwether Lewis and his close friend Second Lieutenant William Clark. Clark and 30 members set out from Camp Dubois, Illinois, on May 14, 1804, met Lewis and ten other members of the group in St. Charles, Missouri, then went up the Missouri River. The expedition crossed the Continental Divide of the Americas near the Lemhi Pass, eventually coming to the Columbia River, and the Pacific Ocean in 1805. The return voyage began on March 23, 1806, at Fort Clatsop, Oregon, and ended on September 23 of the same year. President Thomas Jefferson commissioned the expedition shortly after the Louisiana Purchase in 1803 to explore and to map the newly acquired territory, to find a pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louisiana Purchase
The Louisiana Purchase (french: Vente de la Louisiane, translation=Sale of Louisiana) was the acquisition of the territory of Louisiana by the United States from the French First Republic in 1803. In return for fifteen million dollars, or approximately eighteen dollars per square mile, the United States nominally acquired a total of in Middle America. However, France only controlled a small fraction of this area, most of which was inhabited by Native Americans; effectively, for the majority of the area, the United States bought the "preemptive" right to obtain "Indian" lands by treaty or by conquest, to the exclusion of other colonial powers. The Kingdom of France had controlled the Louisiana territory from 1699 until it was ceded to Spain in 1762. In 1800, Napoleon, the First Consul of the French Republic, regained ownership of Louisiana as part of a broader effort to re-establish a French colonial empire in North America. However, France's failure to suppress a revol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nebraska Territory
The Territory of Nebraska was an organized incorporated territory of the United States that existed from May 30, 1854, until March 1, 1867, when the final extent of the territory was admitted to the Union as the State of Nebraska. The Nebraska Territory was created by the Kansas–Nebraska Act of 1854. The territorial capital was Omaha. The territory encompassed areas of what is today Nebraska, Wyoming, South Dakota, North Dakota, Colorado, and Montana. History An enabling act was passed by Congress in 1864. Delegates for a constitutional convention were elected; this convention did not produce a constitution. Two years later, in 1866, a constitution was drafted and voted upon. It was approved by 100 votes. However, a clause in this constitution that limited suffrage to "free white males" delayed Nebraska's entry into the Union for almost a year. The 1866 enabling act for the state was subject to a pocket veto by President Andrew Johnson. When Congress reconvened in 1867, it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollusca
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is estimated between 60,000 and 100,000 additional species. The proportion of undescribed species is very high. Many taxa remain poorly studied. Molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats. They are highly diverse, not just in size and anatomical structure, but also in behaviour and habitat. The phylum is typically divided into 7 or 8 taxonomic classes, of which two are entirely extinct. Cephalopod molluscs, such as squid, cuttlefish, and octopuses, are among the most neurologically advanced of all invertebrates—and either the giant squid or the colossal squid is the largest known invertebrate species. The gastropod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
