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Dunkleosteus BW
''Dunkleosteus'' is an extinct genus of large armored, jawed fishes that existed during the Late Devonian period, about 382–358 million years ago. It consists of ten species, some of which are among the largest placoderms to have ever lived: ''D. terrelli'', ''D. belgicus'', ''D. denisoni'', ''D. marsaisi'', ''D. magnificus'', ''D. missouriensis'', ''D. newberryi'', ''D. amblyodoratus'', and ''D. raveri''. The largest and most well known species is ''D. terrelli'', which grew up to long and in weight. ''Dunkleosteus'' could quickly open and close its jaw, like modern-day suction feeders, and had a bite force of at the tip and at the blade edge. Numerous fossils of the various species have been found in North America, Poland, Belgium, and Morocco. Etymology ''Dunkleosteus'' was named in 1956 to honour David Dunkle (1911–1982), former curator of vertebrate paleontology at the Cleveland Museum of Natural History. The genus name ''Dunkleosteus'' combines David Dunkle's ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Devonian
The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, where rocks from this period were first studied. The first significant adaptive radiation of life on dry land occurred during the Devonian. Free-sporing vascular plants began to spread across dry land, forming extensive forests which covered the continents. By the middle of the Devonian, several groups of plants had evolved leaves and true roots, and by the end of the period the first seed-bearing plants appeared. The arthropod groups of myriapods, arachnids and hexapods also became well-established early in this period, after starting their expansion to land at least from the Ordovician period. Fish reached substantial diversity during this time, leading the Devonian to often be dubbed the Age of Fishes. The placoderms began dominating ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Belgium
Belgium, ; french: Belgique ; german: Belgien officially the Kingdom of Belgium, is a country in Northwestern Europe. The country is bordered by the Netherlands to the north, Germany to the east, Luxembourg to the southeast, France to the southwest, and the North Sea to the northwest. It covers an area of and has a population of more than 11.5 million, making it the 22nd most densely populated country in the world and the 6th most densely populated country in Europe, with a density of . Belgium is part of an area known as the Low Countries, historically a somewhat larger region than the Benelux group of states, as it also included parts of northern France. The capital and largest city is Brussels; other major cities are Antwerp, Ghent, Charleroi, Liège, Bruges, Namur, and Leuven. Belgium is a sovereign state and a federal constitutional monarchy with a parliamentary system. Its institutional organization is complex and is structured on both regional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other evolutionary narratives about an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monotypic Taxon
In biology, a monotypic taxon is a taxonomic group ( taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispecific" or "monospecific" is sometimes preferred. In botanical nomenclature, a monotypic genus is a genus in the special case where a genus and a single species are simultaneously described. In contrast, an oligotypic taxon contains more than one but only a very few subordinate taxa. Examples Just as the term ''monotypic'' is used to describe a taxon including only one subdivision, the contained taxon can also be referred to as monotypic within the higher-level taxon, e.g. a genus monotypic within a family. Some examples of monotypic groups are: Plants * In the order Amborellales, there is only one family, Amborellaceae and there is only one genus, '' Amborella'', and in this genus there is only one species, namely ''Amborella trichopod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eastmanosteus
''Eastmanosteus'' ("Eastman's bone") is a fossil genus of dunkleosteid placoderms. It was closely related to the giant ''Dunkleosteus'', but differed from that genus in size, in possessing a distinctive tuberculated bone ornament, a differently shaped nuchal plate and a more zig-zagging course of the sutures of the skull roof.http://www.ivpp.cas.cn/cbw/gjzdwxb/xbwzxz/200812/W020090813371138329343.pdf Species of ''Eastmanosteus'' had powerful jaws with sharp cutting edges and were likely active predators. Fossils have been found in many parts of the world in marine sediments dating from the Middle to Late Devonian. They were medium-to-large fish, with specimens ''E. pustulosus'' and ''E. licharevi'' approaching a total length of 3 metres. Complete exoskeletons with soft-tissue traces of ''E. calliaspis'' from Australia make this one of the best known dunkleosteids. Phylogeny ''Eastmanosteus'' and its relative ''Dunkleosteus'' belong to the family Dunkleosteidae. The phylogeny of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dunkleosteidae
Dunkleosteidae is an extinct family of arthrodire placoderms that lived during the Devonian period. The gigantic apex predator ''Dunkleosteus terrelli'' is the best known member of this group. Phylogeny While members of Dunkleosteidae were previously thought to be close relatives of the genus '' Dinichthys'' (when they were not synonymized as each other) and grouped together in the family Dinichthyidae, more recent phylogenetic studies have shown that the two taxa represent two very distinct clades within Arthrodira. Dunkleosteidae was then established as the sister taxon to the family Panxiosteidae, which together comprised the superfamily Dunkleosteoidea (one of the three major clades of Eubrachythoraci). Dunkleosteidae was thus cladistically defined as including the type genus ''Dunkleosteus'' and all other genera in Dunkleosteoidea more closely related to ''Dunkleosteus'' than to '' Panxiosteus''. The phylogeny of Dunkleosteidae from the 2013 Zhu & Zhu study is shown ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between org ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinichthyidae
''Dinichthys'' (from el, δεινός , 'terrible' and el, ἰχθύς 'fish') is an extinct monospecific genus of giant, marine arthrodire placoderm from the Late Devonian (Famennian stage), comparable in size, shape, and ecological role to the better-known ''Dunkleosteus''. Fossils were recovered from the Ohio Shale Formation along the Olentangy River in Delaware County, Ohio. Classification History ''Dinichthys'' was originally described in 1868 by John Newberry on the basis of an incomplete skull roof and mandibles (holotype AMNH 81). Subsequently, many unrelated large arthrodires were originally classified together within this genus, including species now assigned to ''Dunkleosteus'', '' Eastmanosteus'', and ''Titanichthys''. Notably, the type species of ''Dunkleosteus'' was originally described as ''Dinichthys terrelli'' by Newberry in 1873, and was later separated into ''Dunkleosteus'' by Jean-Pierre Lehman in 1956. ''Dunkleosteus'' was still thought to be close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Type Species
In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen(s). Article 67.1 A similar concept is used for suprageneric groups and called a type genus. In botanical nomenclature, these terms have no formal standing under the code of nomenclature, but are sometimes borrowed from zoological nomenclature. In botany, the type of a genus name is a specimen (or, rarely, an illustration) which is also the type of a species name. The species name that has that type can also be referred to as the type of the genus name. Names of genus and family ranks, the various subdivisions of those ranks, and some higher-rank names based on genus names, have such types. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cleveland Museum Of Natural History
The Cleveland Museum of Natural History is a natural history museum located approximately five miles (8 km) east of downtown Cleveland, Ohio in University Circle, a 550-acre (220 ha) concentration of educational, cultural and medical institutions. The museum was established in 1920 by Cyrus S. Eaton to perform research, education and development of collections in the fields of anthropology, archaeology, astronomy, botany, geology, paleontology, wildlife biology, and zoology. The museum traces its roots to the Ark, formed in 1836 on Cleveland's Public Square by William Case, the Academy of Natural Science formed by William Case and Jared Potter Kirtland, and the Kirtland Society of Natural History, founded in 1869 and reinvigorated in 1922 by the trustees of the Cleveland Museum of Natural History. Donald Johanson was the curator of the museum when he discovered "Lucy," the skeletal remains of the ancient hominid ''Australopithecus afarensis''. The current Curator and Hea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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