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Gerrothorax
''Gerrothorax'' ("wicker chest") is an extinct genus of temnospondyl amphibian from the Triassic period of Greenland, Germany, Poland, Sweden, and possibly Thailand. It is known from a single species, ''G. pulcherrimus'', although several other species such as ''G. pustuloglomeratus'' have been named in the past. ''Gerrothorax'' was about long, and had a remarkably flattened body. It probably hid under sand or mud on river and lake bottoms, scanning for prey with its large, upward-facing eyes. ''Gerrothorax'' had an unusually shaped skull with angular protrusions on the sides. This looked vaguely similar to the skull of the earlier, unrelated, amphibian ''Diplocaulus'', but was not so developed. Some ''Gerrothorax'' fossils preserved hypobranchials anceratobranchials(bony gill arches) near the neck. This shows that ''Gerrothorax'' was pedomorphic, retaining its larval gills as an adult. When originally described in 1946, these bones were considered to correspond to feather-lik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerrothorax BW
''Gerrothorax'' ("wicker chest") is an extinct genus of temnospondyl amphibian from the Triassic period of Greenland, Germany, Poland, Sweden, and possibly Thailand. It is known from a single species, ''G. pulcherrimus'', although several other species such as ''G. pustuloglomeratus'' have been named in the past. ''Gerrothorax'' was about long, and had a remarkably flattened body. It probably hid under sand or mud on river and lake bottoms, scanning for prey with its large, upward-facing eyes. ''Gerrothorax'' had an unusually shaped skull with angular protrusions on the sides. This looked vaguely similar to the skull of the earlier, unrelated, amphibian ''Diplocaulus'', but was not so developed. Some ''Gerrothorax'' fossils preserved hypobranchials anceratobranchials(bony gill arches) near the neck. This shows that ''Gerrothorax'' was pedomorphic, retaining its larval gills as an adult. When originally described in 1946, these bones were considered to correspond to feather-lik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temnospondyl
Temnospondyli (from Greek language, Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order (biology), order of small to giant tetrapods—often considered Labyrinthodontia, primitive amphibians—that flourished worldwide during the Carboniferous, Permian, and Triassic periods. A few species continued into the Jurassic and Cretaceous periods. Fossils have been found on every continent. During about 210 million years of evolutionary history, they adapted to a wide range of habitats, including freshwater, terrestrial, and even coastal marine environments. Their life history is well understood, with fossils known from the larval stage, metamorphosis, and maturity. Most temnospondyls were semiaquatic, although some were almost fully terrestrial, returning to the water only to breed. These temnospondyls were some of the first vertebrates fully adapted to life on land. Although temnospondyls are considered amphibians, many had cha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ladinian
The Ladinian is a stage and age in the Middle Triassic series or epoch. It spans the time between Ma and ~237 Ma (million years ago). The Ladinian was preceded by the Anisian and succeeded by the Carnian (part of the Upper or Late Triassic). The Ladinian is coeval with the Falangian regional stage used in China. Stratigraphic definitions The Ladinian was established by Austrian geologist Alexander Bittner in 1892. Its name comes from the Ladin people that live in the Italian Alps (in the Dolomites, then part of Austria-Hungary). The base of the Ladinian Stage is defined as the place in the stratigraphic record where the ammonite species '' Eoprotrachyceras curionii'' first appears or the first appearance of the conodont ''Budurovignathus praehungaricus''. The global reference profile for the base (the GSSP) is at an outcrop in the river bed of the Caffaro river at Bagolino, in the province of Brescia, northern Italy.The GSSP was established by Brack ''et al.'' (2005) The t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gill
A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are kept moist. The microscopic structure of a gill presents a large surface area to the external environment. Branchia (pl. branchiae) is the zoologists' name for gills (from Ancient Greek ). With the exception of some aquatic insects, the filaments and lamellae (folds) contain blood or coelomic fluid, from which gases are exchanged through the thin walls. The blood carries oxygen to other parts of the body. Carbon dioxide passes from the blood through the thin gill tissue into the water. Gills or gill-like organs, located in different parts of the body, are found in various groups of aquatic animals, including mollusks, crustaceans, insects, fish, and amphibians. Semiterrestrial marine animals such as crabs and mudskippers have gill cham ... [...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] |
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and Ma (million years ago). It is preceded by the Early Triassic Epoch and followed by the Late Triassic Epoch. The Middle Triassic is divided into the Anisian and Ladinian ages or stages. Formerly the middle series in the Triassic was also known as Muschelkalk. This name is now only used for a specific unit of rock strata with approximately Middle Triassic age, found in western Europe. Middle Triassic fauna Following the Permian–Triassic extinction event, the most devastating of all mass-extinctions, life recovered slowly. In the Middle Triassic, many groups of organisms reached higher diversity again, such as the marine reptiles (e.g. ichthyosaurs, sauropterygians, thallatosaurs), ray-finned fish and many invertebrate groups like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cranial Kinesis
Cranial kinesis is the term for significant movement of skull bones relative to each other in addition to movement at the joint between the upper and lower jaw. It is usually taken to mean relative movement between the upper jaw and the braincase. Most vertebrates have some form of kinetic skull. Cranial kinesis, or lack thereof, is usually linked to feeding. Animals which must exert powerful bite forces, such as crocodiles, often have rigid skulls with little or no kinesis, for maximum strength. Animals which swallow large prey whole (snakes), which grip awkwardly shaped food items (parrots eating nuts), or, most often, which feed in the water via suction feeding often have very kinetic skulls, frequently with numerous mobile joints. In the case of mammals, which have akinetic skulls (except for perhaps hares), the lack of kinesis is most likely to be related to the secondary palate, which prevents relative movement. This in turn is a consequence of the need to be able to create ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeontology (journal)
''Palaeontology'' is one of the two scientific journals of the Palaeontological Association (the other being '' Papers in Palaeontology''). It was established in 1957 and is published on behalf of the Association by Wiley-Blackwell. The editor-in-chief is Barry Lomax (University of Nottingham). ''Palaeontology'' publishes articles on a range of palaeontological topics, including taphonomy, functional morphology, systematics, palaeo-environmental reconstruction and biostratigraphy. According to the ''Journal Citation Reports'', the journal has a 2017 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 3.730, ranking it 1st out of 55 journals in the category "Paleontology". References External links * Paleontology journals Publications established in 1957 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palatoquadrate
In some fishes, the palatoquadrate is the dorsal component of the mandibular arch, the ventral one being Meckel's cartilage. The palatoquadrate forms from splanchnocranium in various chordates including placoderms and acanthodians. See also * Hyomandibula * Fish anatomy * Helicoprion ''Helicoprion'' is an extinct genus of shark-like eugeneodont fish. Almost all fossil specimens are of spirally arranged clusters of the individuals' teeth, called "tooth whorls", which in life were embedded in the lower jaw. As with most extin ... References * Fish anatomy {{paleo-fish-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Braincase
In human anatomy, the neurocranium, also known as the braincase, brainpan, or brain-pan is the upper and back part of the skull, which forms a protective case around the brain. In the human skull, the neurocranium includes the calvaria or skullcap. The remainder of the skull is the facial skeleton. In comparative anatomy, neurocranium is sometimes used synonymously with endocranium or chondrocranium. Structure The neurocranium is divided into two portions: * the membranous part, consisting of flat bones, which surround the brain; and * the cartilaginous part, or chondrocranium, which forms bones of the base of the skull. In humans, the neurocranium is usually considered to include the following eight bones: * 1 ethmoid bone * 1 frontal bone * 1 occipital bone * 2 parietal bones * 1 sphenoid bone * 2 temporal bones The ossicles (three on each side) are usually not included as bones of the neurocranium. There may variably also be extra sutural bones present. Below the ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microtomography
X-ray microtomography, like tomography and X-ray computed tomography, uses X-rays to create cross-sections of a physical object that can be used to recreate a virtual model (3D model) without destroying the original object. The prefix ''micro-'' (symbol: µ) is used to indicate that the pixel sizes of the cross-sections are in the micrometre range. These pixel sizes have also resulted in the terms high-resolution X-ray tomography, micro–computed tomography (micro-CT or µCT), and similar terms. Sometimes the terms high-resolution CT (HRCT) and micro-CT are differentiated, but in other cases the term high-resolution micro-CT is used. Virtually all tomography today is computed tomography. Micro-CT has applications both in medical imaging and in industrial computed tomography. In general, there are two types of scanner setups. In one setup, the X-ray source and detector are typically stationary during the scan while the sample/animal rotates. The second setup, much more like a cli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Vertebrate Paleontology
The ''Journal of Vertebrate Paleontology'' is a bimonthly peer-reviewed scientific journal that was established in 1980 by Jiri Zidek (University of Oklahoma). It covers all aspects of vertebrate paleontology, including vertebrate origins, evolution, functional morphology, taxonomy, biostratigraphy, paleoecology, paleobiogeography, and paleoanthropology. The journal is published by Taylor & Francis on behalf of the Society of Vertebrate Paleontology. According to ''Journal Citation Reports'', the journal has a 2017 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 2.190. References External links * Paleontology journals Publications established in 1980 Quarterly journals English-language journals Taylor & Francis academic journals {{paleontology-jou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
