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Caviramus
''Caviramus'' is a genus of caviramid pterosaur from the Late Triassic (early Rhaetian-age) lower Kössen Formation of the Northern Calcareous Alps of Switzerland. The genus was in 2006 named by Nadia Fröbisch and Jörg Fröbisch. The type species is ''Caviramus schesaplanensis''. The genus name is derived from Latin ''cavus'', "hollow" and ''ramus'', "branch". The specific name refers to Mount Schesaplana. Description The genus is based on holotype PIMUZ A/III 1225, three non-contiguous fragments of a ramus (lower jaw) of the mandible with multicuspate teeth. Two teeth are preserved, one with three cusps, and one with four; despite this difference the authors consider them as essentially isodont. The number of teeth is estimated at a minimum of twelve and a maximum of seventeen. A row of large oval foramina runs parallel to the tooth row; foramina in the form of small holes in the anterior part of the lower jaw suggest some sort of soft-tissue structure, or a keratin c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raeticodactylus Filisurensis
''Raeticodactylus'' is a genus of non-pterodactyloid pterosaur from the late Norian-early Rhaetian-age Upper Triassic lower Kössen Formation of the central Austroalpine of Grisons, Switzerland. It is known from holotype BNM 14524, a single disarticulated partial skeleton including an almost complete skull, found in August 2005. This genus was named and described in 2008 by its discoverer Rico Stecher; the type species is ''Raeticodactylus filisurensis''. The specific name refers to Filisur. Online First Description ''Raeticodactylus'' had a tall thin bony crest running along the midline of the front of the upper jaw, and a keel on the lower jaw; however, it does not seem to be closely related to ''Austriadactylus'', the only other crested Triassic pterosaur named by the time ''Raeticodactylus'' was described. The teeth at the front of the upper jaw, in the premaxillae, were fanglike, whereas the teeth in the upper cheeks (the maxillae) had three, four, or five cusps, similar t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caviramid
Caviramidae is a group of basal pterosaurs. It was erected by paleontologist Matthew G. Baron in 2020. It was defined as the least inclusive clade that includes '' Arcticodactylus cromptonellus'' and ''Caviramus schesaplanensis''. The members of Caviramidae are also considered to belong to either the family Eudimorphodontidae (''Arcticodactylus'' and ''Carniadactylus''), the family Raeticodactylidae (''Caviramus'' and ''Raeticodactylus''), or just basal eopterosaurians (''Austriadraco ''Austriadraco'' is a genus of pterosaur living during the Late Triassic in the area of present Austria. Its only species—''Austriadraco dallavecchiai''—was previously attributed to ''Eudimorphodon'', and its closest relatives may have been ' ...'' and '' Seazzadactylus''). However, Baron, the author of Caviramidae, concluded in his analyses that both Eopterosauria and Eudimorphodontidae are not monophyletic groups, therefore he created the family Caviramidae to contain most of the eudimorph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carniadactylus
''Carniadactylus'' is a genus of pterosaur which existed in Europe during the Late Triassic period (late Carnian or early Norian, about 228 million years agoBarrett, P. M., Butler, R. J., Edwards, N. P., & Milner, A. R. (2008). Pterosaur distribution in time and space: an atlas. ''Zitteliana'', 61-107/ref>). The genus contains a single species, ''Carniadactylus rosenfeldi''. Description ''Carniadactylus'' was similar in appearance and anatomy to its close relative ''Eudimorphodon'', though it was significantly smaller. Like ''Eudimorphodon'', it is notable for its complex multi-cusped teeth. Despite their similarities, the size difference between these two pterosaurs likely meant that they occupied different niches and relied on different food sources. This is supported by studies of their teeth. While similar in construction, the teeth of ''Carniadactylus'' show little to no wear, unlike the larger, fish-eating ''Eudimorphodon'', which may have been able to chew its food. The sma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterosaur
Pterosaurs (; from Greek ''pteron'' and ''sauros'', meaning "wing lizard") is an extinct clade of flying reptiles in the order, Pterosauria. They existed during most of the Mesozoic: from the Late Triassic to the end of the Cretaceous (228 to 66 million years ago). Pterosaurs are the earliest vertebrates known to have evolved powered flight. Their wings were formed by a membrane of skin, muscle, and other tissues stretching from the ankles to a dramatically lengthened fourth finger. There were two major types of pterosaurs. Basal pterosaurs (also called 'non-pterodactyloid pterosaurs' or 'rhamphorhynchoids') were smaller animals with fully toothed jaws and, typically, long tails. Their wide wing membranes probably included and connected the hind legs. On the ground, they would have had an awkward sprawling posture, but the anatomy of their joints and strong claws would have made them effective climbers, and some may have even lived in trees. Basal pterosaurs were i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nadia Fröbisch
Nadia Belinda Fröbisch (née Stöcker) is a German vertebrate paleontologist and developmental biologist who specializes in the evolution and development of amphibians. She is currently a professor at the Museum für Naturkunde Berlin in the Leibniz Institute for Research on Evolution and Biodiversity. Academic and professional background Fröbisch obtained her vordiplom (B.Sc. equivalent) at the University of Bonn in Germany (1996-1999), after which she spent a year as a visiting student at the University of Calgary and volunteered at the Royal Tyrell Museum. Following that, she pursued her diploma (M.Sc. equivalent) at the University of Bonn (2000-2003) under the supervision of Martin Sander, where she studied Middle Triassic ichthyosaurs. Fröbisch then went on to pursue her doctoral studies at McGill University (2003-2008) under the supervision of Robert Carroll and Hans Larsson, where she studied the extinct dissorophoid temnospondyls, a close relative of modern amphibians ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eudimorphodon
''Eudimorphodon'' was a pterosaur that was discovered in 1973 by Mario Pandolfi in the town of Cene, Italy and described the same year by Rocco Zambelli. The nearly complete skeleton was retrieved from shale deposited during the Late Triassic (mid to late Norian stage),Wellnhofer, P. (1991). "Summary of Triassic Pterosaurs." ''The Illustrated Encyclopedia of Pterosaurs.'' London, UK: Salamander Books Limited. p. 67. . making ''Eudimorphodon'' one of the oldest pterosaurs known.Cranfield, I. ''The Illustrated Directory of Dinosaurs and Other Prehistoric Creatures''. London: Salamander Books, Ltd. Pp. 280–281. It had a wingspan of about and at the end of its long bony tail may have been a diamond-shaped flap like in the later '' Rhamphorhynchus''. If so, the flap may have helped it steer while maneuvering in the air. ''Eudimorphodon'' is known from several skeletons, including juvenile specimens. Discovery and species ''Eudimorphodon'' currently includes one species, the type ... [...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] |
Incertae Sedis
' () or ''problematica'' is a term used for a taxonomic group where its broader relationships are unknown or undefined. Alternatively, such groups are frequently referred to as "enigmatic taxa". In the system of open nomenclature, uncertainty at specific taxonomic levels is indicated by ' (of uncertain family), ' (of uncertain suborder), ' (of uncertain order) and similar terms. Examples *The fossil plant '' Paradinandra suecica'' could not be assigned to any family, but was placed ''incertae sedis'' within the order Ericales when described in 2001. * The fossil '' Gluteus minimus'', described in 1975, could not be assigned to any known animal phylum. The genus is therefore ''incertae sedis'' within the kingdom Animalia. * While it was unclear to which order the New World vultures (family Cathartidae) should be assigned, they were placed in Aves ''incertae sedis''. It was later agreed to place them in a separate order, Cathartiformes. * Bocage's longbill, ''Motacilla boca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mastication
Chewing or mastication is the process by which food is crushed and ground by teeth. It is the first step of digestion, and it increases the surface area of foods to allow a more efficient break down by enzymes. During the mastication process, the food is positioned by the cheek and tongue between the teeth for grinding. The muscles of mastication move the jaws to bring the teeth into intermittent contact, repeatedly occluding and opening. As chewing continues, the food is made softer and warmer, and the enzymes in saliva begin to break down carbohydrates in the food. After chewing, the food (now called a bolus) is swallowed. It enters the esophagus and via peristalsis continues on to the stomach, where the next step of digestion occurs. Increasing the number of chews per bite increases relevant gut hormones. Studies suggest that chewing may decrease self-reported hunger and food intake. Chewing gum has been around for many centuries; there is evidence that northern Europ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Maxilla
The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The two maxillary bones are fused at the intermaxillary suture, forming the anterior nasal spine. This is similar to the mandible (lower jaw), which is also a fusion of two mandibular bones at the mandibular symphysis. The mandible is the movable part of the jaw. Structure In humans, the maxilla consists of: * The body of the maxilla * Four processes ** the zygomatic process ** the frontal process of maxilla ** the alveolar process ** the palatine process * three surfaces – anterior, posterior, medial * the Infraorbital foramen * the maxillary sinus * the incisive foramen Articulations Each maxilla articulates with nine bones: * two of the cranium: the frontal and ethmoid * seven of the face: the nasal, zygomatic, lacrimal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dental Anatomy
Dental anatomy is a field of anatomy dedicated to the study of human tooth structures. The development, appearance, and classification of teeth fall within its purview. (The function of teeth as they contact one another falls elsewhere, under dental occlusion.) Tooth formation begins before birth, and the teeth's eventual morphology is dictated during this time. Dental anatomy is also a taxonomical science: it is concerned with the naming of teeth and the structures of which they are made, this information serving a practical purpose in dental treatment. Usually, there are 20 primary ("baby") teeth and 32 permanent teeth, the last four being third molars or "wisdom teeth", each of which may or may not grow in. Among primary teeth, 10 usually are found in the maxilla (upper jaw) and the other 10 in the mandible (lower jaw). Among permanent teeth, 16 are found in the maxilla and the other 16 in the mandible. Each tooth has specific distinguishing features. Growing of tooth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, horns, claws, hooves, and the outer layer of skin among vertebrates. Keratin also protects epithelial cells from damage or stress. Keratin is extremely insoluble in water and organic solvents. Keratin monomers assemble into bundles to form intermediate filaments, which are tough and form strong unmineralized epidermal appendages found in reptiles, birds, amphibians, and mammals. Excessive keratinization participate in fortification of certain tissues such as in horns of cattle and rhinos, and armadillos' osteoderm. The only other biological matter known to approximate the toughness of keratinized tissue is chitin. Keratin comes in two types, the primitive, softer forms found in all vertebrates and harder, derived forms found only among saur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
