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Toxicofera
Toxicofera (Greek for "those who bear toxins") is a proposed clade of scaled reptiles (squamates) that includes the Serpentes (snakes), Anguimorpha (monitor lizards, gila monster, and alligator lizards) and Iguania (iguanas, agamas, and chameleons). Toxicofera contains about 4,600 species, (nearly 60%) of extant Squamata. It encompasses all venomous reptile species, as well as numerous related non-venomous species. There is little morphological evidence to support this grouping, however it has been recovered by all molecular analyses as of 2012. The oldest known toxicoferan is ''Cryptovaranoides'', an anguimorph from the Late Triassic of England. Cladistics Toxicofera combines the following groups from traditional classification: * Suborder Serpentes (snakes) * Suborder Iguania (iguanas, agamid lizards, chameleons, etc.) * Infraorder Anguimorpha, consisting of: ** Family Varanidae (monitor lizards) ** Family Anguidae ( alligator lizards, glass lizards, etc.) ** Family Helo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squamata
Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest order of reptiles, comprising lizards, snakes, and amphisbaenians (worm lizards), which are collectively known as squamates or scaled reptiles. With over 10,900 species, it is also the second-largest order of extant (living) vertebrates, after the perciform fish. Members of the order are distinguished by their skins, which bear horny scales or shields, and must periodically engage in molting. They also possess movable quadrate bones, making possible movement of the upper jaw relative to the neurocranium. This is particularly visible in snakes, which are able to open their mouths very wide to accommodate comparatively large prey. Squamata is the most variably sized order of reptiles, ranging from the dwarf gecko (''Sphaerodactylus ariasae'') to the Reticulated python (''Malayopython reticulatus'') and the now-extinct mosasaurs, which reached lengths over . Among other reptiles, squamates are most close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squamata
Squamata (, Latin ''squamatus'', 'scaly, having scales') is the largest order of reptiles, comprising lizards, snakes, and amphisbaenians (worm lizards), which are collectively known as squamates or scaled reptiles. With over 10,900 species, it is also the second-largest order of extant (living) vertebrates, after the perciform fish. Members of the order are distinguished by their skins, which bear horny scales or shields, and must periodically engage in molting. They also possess movable quadrate bones, making possible movement of the upper jaw relative to the neurocranium. This is particularly visible in snakes, which are able to open their mouths very wide to accommodate comparatively large prey. Squamata is the most variably sized order of reptiles, ranging from the dwarf gecko (''Sphaerodactylus ariasae'') to the Reticulated python (''Malayopython reticulatus'') and the now-extinct mosasaurs, which reached lengths over . Among other reptiles, squamates are most close ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Venom (poison)
Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a stinger, in a process called envenomation. Venom is often distinguished from poison, which is a toxin that is passively delivered by being ingested, inhaled, or absorbed through the skin, and toxungen, which is actively transferred to the external surface of another animal via a physical delivery mechanism. Venom has evolved in terrestrial and marine environments and in a wide variety of animals: both predators and prey, and both vertebrates and invertebrates. Venoms kill through the action of at least four major classes of toxin, namely necrotoxins and cytotoxins, which kill cells; neurotoxins, which affect nervous systems; myotoxins, which damage muscles; and haemotoxins, which disrupt blood clotting. Venomous animals cause tens of thousa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anguimorpha
The Anguimorpha is a suborder of squamates. The group was named by Fürbringer in 1900 to include all autarchoglossans closer to '' Varanus'' and '' Anguis'' than ''Scincus ''Scincus'' is a genus of skinks, lizards in the family Scincidae. The genus contains four or five species, all of which are typical desert inhabitants, living in sandy and dune-like areas with a hot and dry climate. Species in the genus ''Scinc ...''. These lizards, along with iguanians and snakes, constitute the proposed "venom clade" Toxicofera of all venomous reptiles. Evolution The oldest widely accepted member of Anguimorpha is ''Dorsetisaurus'' from the Late Jurassic of Europe and North America. In 2022, the genus ''Cryptovaranoides'' was described from the latest Triassic (Rhaetian) of England. ''Cryptovaranoides'' was recovered in the study as a crown-group Anguimorph, and therefore the oldest crown group-squamate, 35 million years older than any previously known crown-group squamate. Famili ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptovaranoides
''Cryptovaranoides'' ("hidden lizard-like animal") is an extinct genus of lizard from the Late Triassic of England. It contains a single species, ''Cryptovaranoides microlanius''. It is represented by a holotype partial skeleton as well as referred isolated bones from Rhaetian-aged fissure fill-deposits in Cromhall Quarry, near Tortworth, Gloucestershire preserved alongside the common fossil rhynchocephalian ''Clevosaurus''. The type specimen had been collected in 1953, but was only described as a distinct taxon in 2022. Several traits such as braincase, neck vertebrae, skull architecture, and teeth arrangement support ''Cryptovaranoides''' classification as a squamate. ''Cryptovaranoides'' marks the earliest known occurrence of a crown group squamate, with previous fossils known only as early as the Middle Jurassic; the discovery of ''Cryptovaranoides'' pushes back the estimated origin of modern squamates by 35 million years. A phylogenetic analysis placed ''Cryptovaranoides'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reptile
Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians (tuatara). As of March 2022, the Reptile Database includes about 11,700 species. In the traditional Linnaean classification system, birds are considered a separate class to reptiles. However, crocodilians are more closely related to birds than they are to other living reptiles, and so modern cladistic classification systems include birds within Reptilia, redefining the term as a clade. Other cladistic definitions abandon the term reptile altogether in favor of the clade Sauropsida, which refers to all amniotes more closely related to modern reptiles than to mammals. The study of the traditional reptile orders, historically combined with that of modern amphibians, is called herpetology. The earliest known proto-reptiles originated around ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BMC Evolutionary Biology
''BMC Ecology and Evolution'' (since January 2021), previously ''BMC Evolutionary Biology'' (2001–2020), is a peer-reviewed open access scientific journal covering all fields of evolutionary biology, including phylogenetics and palaeontology. It was established in 2001 and is part of a series of BMC journals published by BioMed Central. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2020 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly mean number of citations of articles published in the last two years in a given journal, as i ... of 3.260. References External links * BioMed Central academic journals Creative Commons Attribution-licensed journals {{biology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biology Letters
''Biology Letters'' is a peer-reviewed, biological, scientific journal published by the Royal Society. It focuses on the rapid publication of short high quality research articles, reviews and opinion pieces across the biological sciences. ''Biology Letters'' has an average turnaround time of twenty four days from submission to a first decision. The editor-in-chief is Professor David Beerling FRS (University of Sheffield) who is supported by an international Editorial Board of practising scientists. Contents and themes As well as the conventional, short research articles, ''Biology Letters'' has recently published Special Features and Mini Series. While Special Features are a collection of up to 20 articles on a specific theme and published across multiple issues, Mini Series include up to six articles that are published in one issue. Examples of topics in these formats include ocean acidification, fossils, extinction, enhanced rock weathering and the evolutionary ecology of sp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rattlesnake
Rattlesnakes are venomous snakes that form the genera ''Crotalus'' and ''Sistrurus'' of the subfamily Crotalinae (the pit vipers). All rattlesnakes are vipers. Rattlesnakes are predators that live in a wide array of habitats, hunting small animals such as birds and rodents. Rattlesnakes receive their name from the rattle located at the end of their tails, which makes a loud rattling noise when vibrated that deters predators or serves as a warning to passers-by. Rattlesnakes are the leading contributor to snakebite injuries in North America, but rarely bite unless provoked or threatened; if treated promptly, the bites are seldom fatal. The 36 known species of rattlesnakes have between 65 and 70 subspecies, all native to the Americas, ranging from British Columbia through Ontario in southern Canada, to central Argentina. The largest rattlesnake, the eastern diamondback, can measure up to in length. Rattlesnakes are preyed upon by hawks, weasels, king snakes, and a variety ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series (stratigraphy), series of rock beds is known as the Upper Triassic. The Late Triassic is divided into the Carnian, Norian and Rhaetian Geologic time scale, Ages. Many of the first dinosaurs evolved during the Late Triassic, including ''Plateosaurus'', ''Coelophysis'', and ''Eoraptor''. The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. Etymology The Triassic was named in 1834 by Friedrich August von Namoh, Friedrich von Alberti, after a succession of three distinct rock layers (Greek meaning 'triad') that are widespread in southern Germany: the lower Buntsandstein (colourful sandstone'')'', t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science Advances
''Science Advances'' is a peer-reviewed multidisciplinary open-access scientific journal established in early 2015 and published by the American Association for the Advancement of Science. The journal's scope includes all areas of science, including life sciences, physical sciences, social sciences Social science is one of the branches of science, devoted to the study of societies and the relationships among individuals within those societies. The term was formerly used to refer to the field of sociology, the original "science of so ..., computer sciences, and environmental sciences. History The journal was announced in February 2014, and the first articles were published in early 2015. In 2019, ''Science Advances'' surpassed Science (journal), ''Science magazine'' in the number of monthly submissions, becoming the largest member in the Science family of journals. It is the only member of that family where all papers are gold open access. Editorial structure Editori ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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