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Dakotadon
''Dakotadon'' (meaning "Dakota tooth") is a genus of iguanodont dinosaur from the Barremian-age Lower Cretaceous Lakota Formation of South Dakota, USA, known from a partial skull. It was first described in 1989 as '' Iguanodon lakotaensis'', by David B. Weishampel and Philip R. Bjork. Its assignment has been controversial. Some researchers suggest that ''"I." lakotaensis'' was more basal than ''I. bernissartensis'', and related to ''Theiophytalia'',Brill, Kathleen and Kenneth Carpenter. 2007. "A description of a new ornithopod from the Lytle Member of the Purgatoire Formation (Lower Cretaceous) and a reassessment of the skull of ''Camptosaurus''." ''Horns and Beaks'', 49–67. but David Norman has suggested that it was a synonym of ''I. bernissartensis''. Gregory S. Paul Gregory Scott Paul (born December 24, 1954) is an American freelance researcher, author and illustrator who works in paleontology, and more recently has examined sociology and theology. He is best known fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iguanodon
''Iguanodon'' ( ; meaning 'iguana-tooth'), named in 1825, is a genus of iguanodontian dinosaur. While many species have been classified in the genus ''Iguanodon'', dating from the late Jurassic Period to the early Cretaceous Period of Asia, Europe, and North America, taxonomic revision in the early 21st century has defined ''Iguanodon'' to be based on one well-substantiated species: ''I. bernissartensis'', which lived from the late Barremian to the earliest Aptian ages ( Early Cretaceous) in Belgium, Germany, England, Spain, and possibly elsewhere in Europe, between about 126 and 122 million years ago. ''Iguanodon'' was a large, bulky herbivore, measuring up to in length and in body mass. Distinctive features include large thumb spikes, which were possibly used for defense against predators, combined with long prehensile fifth fingers able to forage for food. The genus was named in 1825 by English geologist Gideon Mantell but discovered by William Harding Bensted, bas ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2008 In Paleontology
Protozoa New taxa Plants Angiosperms Monocots Arthropoda Arachnids Insects Xiphosurans Fishes Bony fish Placoderms General research *Hilton & Grande redescribe the fossil mooneyes of western North America synonymizing the genus ''Eohiodon'' with ''Hiodon''. *Cicimurri, Paris, & Everhart describe a partial dentition from a Holocephali chimaeroid fish found in the Niobrara Chalk. Amphibians Jenkins, F. A., jr, Shubin, N. H., Gatesy, S. M., and Warren, A., 2008, Gerrothorax pulcherrimus from the Upper Triassic Fleming Fjord Formation of East Greenland and a reassessment of head lifting in temnospondyl feeding: Journal of Vertebrate Paleontology, v. 28, n. 4, p. 935-950. Newly named amphibians Archosaurs Newly named pseudosuchians Newly named pterosaurs Dinosaurs * Oviraptorosaurian eggs with embryonic skeletons are discovered for the first time in China. * Mongolian Late Jurassic theropod fossils are found for the first time. * A new study on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lakota Formation
The Lakota Formation is a sequence of rocks of early Cretaceous (Berriasian to Barremian) age from Western North America. Located in South Dakota, the name of the formation is derived from the Lakota Native American tribe. There are two units of the Lakota Formation, the Chilson Member (upper Berriasian to Valanginian) and the underlying Fuson Member (upper Valanginian to early Barremian). A Berriasian-Valanginian In the geologic timescale, the Valanginian is an age or stage of the Early or Lower Cretaceous. It spans between 139.8 ± 3.0 Ma and 132.9 ± 2.0 Ma (million years ago). The Valanginian Stage succeeds the Berriasian Stage of the Lower Cretaceou ... age for the Chilson Member has been extrapolated by means of ostracods and charophytes. Vertebrate paleofauna Dinosaurs Mammals Turtles References Geologic formations of South Dakota Cretaceous geology of South Dakota Cretaceous Manitoba Cretaceous geology of Nebraska Berriasian Stage Valanginian Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous
The Early Cretaceous ( geochronological name) or the Lower Cretaceous (chronostratigraphic name), is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 145 Ma to 100.5 Ma. Geology Proposals for the exact age of the Barremian-Aptian boundary ranged from 126 to 117 Ma until recently (as of 2019), but based on drillholes in Svalbard the defining early Aptian Oceanic Anoxic Event 1a (OAE1a) was carbon isotope dated to 123.1±0.3 Ma, limiting the possible range for the boundary to c. 122–121 Ma. There is a possible link between this anoxic event and a series of Early Cretaceous large igneous provinces (LIP). The Ontong Java-Manihiki-Hikurangi large igneous province, emplaced in the South Pacific at c. 120 Ma, is by far the largest LIP in Earth's history. The Ontong Java Plateau today covers an area of 1,860,000 km2. In the Indian Ocean another LIP began to form at c. 120 Ma, the Kerguelen P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By Gregory S
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were set forth in Carl Linnaeus's system in ''Systema Naturae'', 10th edition (1758), as well as an unpublished work by Bernard and Antoine Laurent de Jussieu. The idea of a unit-based system of biological classification was first made widely available in 1805 in the intro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iguanodonts
Iguanodontia (the iguanodonts) is a clade of herbivorous dinosaurs that lived from the Middle Jurassic to Late Cretaceous. Some members include ''Camptosaurus'', ''Dryosaurus'', ''Iguanodon'', ''Tenontosaurus'', and the hadrosaurids or "duck-billed dinosaurs". Iguanodontians were one of the first groups of dinosaurs to be found. They are among the best known of the dinosaurs, and were among the most diverse and widespread herbivorous dinosaur groups of the Cretaceous period. Classification Iguanodontia is often listed as an infraorder within a suborder Ornithopoda, though Benton (2004) lists Ornithopoda as an infraorder and does not rank Iguanodontia. Traditionally, iguanodontians were grouped into the superfamily Iguanodontoidea and family Iguanodontidae. However, phylogenetic studies show that the traditional "iguanodontids" are a paraphyletic grade leading up to the hadrosaurs (duck-billed dinosaurs). Groups like Iguanodontoidea are sometimes still used as unranked clades in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fossil Taxa Described In 2008
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved in amber, hair, petrified wood and DNA remnants. The totality of fossils is known as the ''fossil record''. Paleontology is the study of fossils: their age, method of formation, and evolutionary significance. Specimens are usually considered to be fossils if they are over 10,000 years old. The oldest fossils are around 3.48 billion years old to 4.1 billion years old. Early edition, published online before print. The observation in the 19th century that certain fossils were associated with certain rock strata led to the recognition of a geological timescale and the relative ages of different fossils. The development of radiometric dating techniques in the early 20th century allowed scientists to quantitatively measure the abso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosaurs Of North America
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya; their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. Dinosaurs are varied from taxonomic, morphological and ecological standpoints. Birds, at over 10,700 living species, are among the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Cretaceous Dinosaurs Of North America
{{disambiguation, geo ...
Early may refer to: History * The beginning or oldest part of a defined historical period, as opposed to middle or late periods, e.g.: ** Early Christianity ** Early modern Europe Places in the United States * Early, Iowa * Early, Texas * Early Branch, a stream in Missouri * Early County, Georgia Other uses * ''Early'' (Scritti Politti album), 2005 * ''Early'' (A Certain Ratio album), 2002 * Early (name) * Early effect, an effect in transistor physics * Early Records, a record label * the early part of the morning See also * Earley (other) Earley is a town in England. Earley may also refer to: * Earley (surname), a list of people with the surname Earley * Earley (given name), a variant of the given name Earlene * Earley Lake, a lake in Minnesota *Earley parser, an algorithm *Earley ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synonym (taxonomy)
The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linnaeus was the first to give a scientific name (under the currently used system of scientific nomenclature) to the Norway spruce, which he called ''Pinus abies''. This name is no longer in use, so it is now a synonym of the current scientific name, ''Picea abies''. * In zoology, moving a species from one genus to another results in a different binomen, but the name is considered an alternative combination rather than a synonym. The concept of synonymy in zoology is reserved for two names at the same rank that refers to a taxon at that rank - for example, the name ''Papilio prorsa'' Linnaeus, 1758 is a junior synonym of ''Papilio levana'' Linnaeus, 1758, being names for different seasonal forms of the species now referred to as ''Araschnia le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Theiophytalia
''Theiophytalia'' is a genus of herbivorous iguanodontian dinosaur from the lower Cretaceous period (Aptian-Albian stage, about 112 million years ago) of Colorado, USA. It contains a single species, ''T. kerri''. Description Detailed comparisons by Brill and Carpenter (2006) also showed that the skull differed in a number of key features from that of ''Camptosaurus'', namely: a longer, heavier, and more rugose snout; a wider dorsal process on the maxilla; a proportionally smaller antorbital fenestra; and stouter quadrate, with a bulbous articulation for the lower jaw. Compare the skull image with that of ''Camptosaurus''. Therefore, they put it into its own genus and species. Discovery In 1878, a student of Colorado College named James Kerr found a partial Ornithopod skull at Garden of the Gods Park in El Paso County, Colorado. The skull, YPM 1887, was referred by O.C. Marsh (affirmed by Gilmore, 1909), to whom the skull was given in 1886, as that of ''Camptosaurus amplus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
