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Bruce Erickson
Bruce R. Erickson (September 29, 1933 – January 16, 2022) was an American paleontologist and the former Fitzpatrick Chair of Paleontology at the Science Museum of Minnesota. During the course of his lifetime and his 55 years as a paleontologist, he has "collected about a million specimens" and discovered fifteen new types of plants and ancient animal species. His collection includes "a triceratops skeleton" that he discovered in 1961 at the Hell Creek Formation that is considered to be "one of the rarest in the world".Estrada, Heron Marquez"Book fleshes out a career studying dinosaur bones" Star Tribune, April 27, 2003 His research has focused almost entirely on the Paleocene era in history. Biography According to Erickson, his interest in paleontology began when he was ten years old and he came across a geologist investigating rocks along the bank of the Mississippi River.Brody, Jane E."26 Years Deep in the Paleocene" Los Angeles Times, September 3, 1996 Career In the 1960s, E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paleontologist
Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geologic time, and assess the interactions between prehistoric organisms and their natural environment. While paleontological observations are known from at least the 6th century BC, the foundation of paleontology as a science dates back to the work of Georges Cuvier in 1796. Cuvier demonstrated evidence for the concept of extinction and how life of the past was not necessarily the same as that of the present. The field developed rapidly over the course of the following decades, and the French word ''paléontologie'' was introduced for the study in 1822, which was derived from the Ancient Greek word for "ancient" and words describing relatedness and a field of study. Further advances in the field accompanied the work of Charles Darwin who popu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River
A river is a natural stream of fresh water that flows on land or inside Subterranean river, caves towards another body of water at a lower elevation, such as an ocean, lake, or another river. A river may run dry before reaching the end of its course if it runs out of water, or only flow during certain seasons. Rivers are regulated by the water cycle, the processes by which water moves around the Earth. Water first enters rivers through precipitation, whether from rainfall, the Runoff (hydrology), runoff of water down a slope, the melting of glaciers or snow, or seepage from aquifers beneath the surface of the Earth. Rivers flow in channeled watercourses and merge in confluences to form drainage basins, or catchments, areas where surface water eventually flows to a common outlet. Rivers have a great effect on the landscape around them. They may regularly overflow their Bank (geography), banks and flood the surrounding area, spreading nutrients to the surrounding area. Sedime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Paleontologists
American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, people who self-identify their ancestry as "American" ** American English, the set of varieties of the English language native to the United States ** Native Americans in the United States, indigenous peoples of the United States * American, something of, from, or related to the Americas, also known as "America" ** Indigenous peoples of the Americas * American (word), for analysis and history of the meanings in various contexts Organizations * American Airlines, U.S.-based airline headquartered in Fort Worth, Texas * American Athletic Conference, an American college athletic conference * American Recordings (record label), a record label that was previously known as Def American * American University, in Washington, D.C. Sports teams S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triceratops
''Triceratops'' ( ; ) is a genus of Chasmosaurinae, chasmosaurine Ceratopsia, ceratopsian dinosaur that lived during the late Maastrichtian age of the Late Cretaceous Period (geology), period, about 68 to 66 million years ago on the island continent of Laramidia, now forming western North America. It was one of the last-known non-avian dinosaurs and lived until the Cretaceous-Paleogene extinction event, Cretaceous–Paleogene extinction event 66 million years ago. The name ''Triceratops'', which means 'three-horned face', is derived from the Ancient Greek, Greek words () meaning 'three', () meaning 'horn', and () meaning 'face'. Bearing a large bony neck frill, frill, three horns on the skull, and a large, four-legged body, exhibiting convergent evolution with bovines and rhinoceroses, ''Triceratops'' is one of the most recognizable of all dinosaurs and the best-known ceratopsian. It was also one of the largest, measuring around long and weighing up to . It shared the la ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mississippi River Valley
The Mississippi embayment is a physiographic feature in the south-central United States, part of the Mississippi Alluvial Plain. It is essentially a northward continuation of the fluvial sediments of the Mississippi River Delta to its confluence with the Ohio River at Cairo, Illinois. The current sedimentary area was formed in the Cretaceous and early Cenozoic by the filling with sediment of a pre-existing basin. An explanation for the embayment's formation was put forward by Van Arsdale and Cox in 2007: movement of the Earth's crust brought this region over a volcanic " hotspot" in the Earth's mantle causing an upthrust of magma which formed the Appalachian-Ouachita range. Subsequent erosion caused a deep trough that was flooded by the Gulf of Mexico and eventually filled with sediment from the Mississippi River. Geography The embayment is a topographically low-lying basin that is filled with Cretaceous to recent sediments. The northern end of the embayment appears as an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wannaganosuchus
''Wannaganosuchus'' (meaning "Wannagan crocodile", in reference to the Wannagan Creek site where it was discovered) is an extinct genus of small alligatorid crocodilian. It was found in Late Paleocene-age rocks of Billings County, North Dakota, United States. History and description ''Wannaganosuchus'' is based on SMM P76.28.247, a mostly complete skull and postcranial skeleton missing some vertebrae, coracoids, part of the feet, ribs, and other pieces. A few small bony scutes are also assigned to the genus, but not to the type specimen. SMM P76.28.247 was found semi-articulated in the lower part of the Bullion Creek Formation, near the base of a lignitic clay layer deposited in a marsh setting on a floodplain. ''Wannaganosuchus'' was named in 1982 by Bruce R. Erickson. The type species is ''W. brachymanus''; the specific name means "short forefoot". The skull of SMM P76.28.247 was low, without elevated rims over the eyes, and was long. The snout was s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Champsosaurus
''Champsosaurus'' is an extinct genus of crocodile-like choristodere reptile, known from the Late Cretaceous and early Paleogene periods of North America and Europe (Campanian–Paleocene). The name ''Champsosaurus'' is thought to come from , () said in an Ancient Greek source to be an Egyptian word for "crocodiles", and , () Greek for "lizard". The morphology of ''Champsosaurus'' resembles that of gharials, with a long, elongated snout. It was native to freshwater environments where it likely preyed on fish, similar to living gharials. History of research ''Champsosaurus'' was the first member of the Choristodera to be described. ''Champsosaurus'' was named by Edward Drinker Cope in 1876, from isolated vertebrae found in Late Cretaceous strata of the Judith River Formation on the banks of the Judith River in Fergus County, Montana. Cope designated ''C. annectens'' as the type species rather than the first named ''C. profundus'' due to the larger number of vertebrae he attribu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Simoedosaurus
''Simoedosaurus'' is an extinct reptile known from the Paleocene of North America, Europe and western Asia, and a member of the Choristodera, a group of aquatic reptiles that lived in the Northern Hemisphere from the Jurassic to the early Cenozoic. A second species, ''S. dakotensis'' got its own genus, '' Kosmodraco'', in 2022. Taxonomy French paleontologist Paul Gervais described ''Simoedosaurus'' in 1877. Though similar to and contemporaneous, ''Simoedosaurus'' is not closely related to the North American ''Champsosaurus'', instead it appears to be most closely related to '' Tchoiria'' and '' Ikechosaurus'' from the Early Cretaceous of Asia. It therefore may represent a species that immigrated into North America from Asia in the wake of the Cretaceous-Tertiary mass extinction event, though the absence of choristoderes in the Late Cretaceous of Asia makes this merely a paleogeographical speculation. Biology ''Simoedosaurus'' was an aquatic predator, specialised to a fully a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oligocene
The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the exact dates of the start and end of the epoch are slightly uncertain. The name Oligocene was coined in 1854 by the German paleontologist Heinrich Ernst Beyrich from his studies of marine beds in Belgium and Germany. The name comes from Ancient Greek (''olígos'') 'few' and (''kainós'') 'new', and refers to the sparsity of Neontology, extant forms of Mollusca, molluscs. The Oligocene is preceded by the Eocene Epoch and is followed by the Miocene Epoch. The Oligocene is the third and final epoch of the Paleogene Period. The Oligocene is often considered an important time of transition, a link between the archaic world of the tropical Eocene and the more modern ecosystems of the Miocene. Major chang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gavialosuchus
''Gavialosuchus'' is an extinct genus of gavialoid crocodylian from the early Miocene of Europe. Currently only one species is recognized, as a few other species of ''Gavialosuchus'' have since been reclassified to other genera. Taxonomy The type species, ''G. eggenburgensis'', is known from the early Miocene of Austria. Two other species - ''G. americanus'' and ''G. carolinensis'' - have since been reclassified to other genera. Myrick Jr. (2001) proposed synonymizing ''Gavialosuchus americanus'' with '' Thecachampsa antiqua''. Piras ''et al.'' (2007) advocated transferring both ''G. americanus'' and ''G. carolinensis'' to ''Thecachampsa'' as distinct species of the latter genus, however. Jouve ''et al.'' (2008) retained ''G. americanus'' in ''Gavialosuchus'' and found it to be the sister group of ''G. eggenburgensis'' (''G. carolinensis'' was not discussed). However, Jouve ''et al.'' (2008) didn't test ''Thecachampsa antiqua'' in their phylogenetic analysis. Shan ''et al.'' ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crocodile
Crocodiles (family (biology), family Crocodylidae) or true crocodiles are large, semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term "crocodile" is sometimes used more loosely to include all extant taxon, extant members of the order (biology), order Crocodilia, which includes the alligators and caimans (both members of the family Alligatoridae), the gharial and false gharial (both members of the family Gavialidae) as well as other extinct Taxon, taxa. Crocodile Measurement, size, Morphology (biology), morphology, behaviour and ecology differ among species. However, they have many similarities in these areas as well. All crocodiles are semiaquatic and tend to congregate in freshwater habitats such as rivers, lakes, wetlands and sometimes in brackish water and Seawater, saltwater. They are carnivorous animals, feeding mostly on vertebrates such as fish, reptiles, birds and mammals, and sometimes on invertebrates such as mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wannagan Creek Site
{{Short description, Fossil site in North Dakota, US The Wannagan Creek site is a fossil site found just west of the South Unit of Theodore Roosevelt National Park of North Dakota, US. The site is Paleocene in age, approximately 60 million years old. Paleontologists of the Science Museum of Minnesota have studied the site for nearly thirty years. The site is thought to represent a paleoenviroment of subtropical swampy lowland and forests. Preservation is excellent for both the flora and fauna of the site. Trace fossils of crocodilians and other vertebrates have also been discovered. Topography/Geology The topography of the site is that of a badland, due to the downcutting of the Little Missouri River. The rock units are likely sediments derived from the Laramide orogeny deposited in an ecosystem dominated by rivers, streams, ponds, lakes, and swamps. The Wannagan Site is found in the upper portion of the Tongue River Formation (formerly Bullion Creek Formation). The rocks of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
