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Euparkeria
''Euparkeria'' (; meaning "Parker's good animal", named in honor of W. K. Parker) is an Extinction, extinct genus of archosauriform reptile from the Triassic of South Africa. ''Euparkeria'' is close to the ancestry of Archosauria, the reptile group that includes crocodilians, pterosaurs, and dinosaurs (including birds). Fossils of ''Euparkeria'', including nearly complete skeletons, have been recovered from the Cynognathus Assemblage Zone, ''Cynognathus'' Assemblage Zone (CAZ, also known as the Burgersdorp Formation), which hosts the oldest advanced archosauriforms in the fossil-rich Karoo Basin. Tentative dating schemes place the CAZ around the latest Early Triassic (late Olenekian stage) or earliest Middle Triassic (early Anisian stage), approximately 247 million years old. ''Euparkeria'' is among the most heavily described and discussed non-archosaur archosauriforms. It was a small carnivorous reptile with a boxy skull, slender limbs, and two rows of tiny teardrop-shaped osteo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archosauriform
Archosauriformes (Greek for 'ruling lizards', and Latin for 'form') is a clade of diapsid reptiles encompassing archosaurs and some of their close relatives. It was defined by Jacques Gauthier (1994) as the clade stemming from the last common ancestor of Proterosuchidae and Archosauria. Phil Senter (2005) defined it as the most exclusive clade containing '' Proterosuchus'' and Archosauria. Gauthier as part of the ''Phylonyms'' (2020) defined the clade as the last common ancestor of '' Gallus'', ''Alligator'', and '' Proterosuchus'', and all its descendants. Archosauriforms are a branch of archosauromorphs which originated in the Late Permian (roughly 252 million years ago) and persist to the present day as the two surviving archosaur groups: crocodilians and birds. Archosauriforms present several traits historically ascribed to the group Archosauria. These include serrated teeth set in deep sockets, a more active metabolism, and an antorbital fenestra (a hole in the skull in fro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archosauriformes
Archosauriformes (Ancient Greek, Greek for 'ruling lizards', and Latin for 'form') is a clade of diapsid reptiles encompassing Archosaur, archosaurs and some of their close relatives. It was defined by Jacques Gauthier (1994) as the clade stemming from the Most recent common ancestor, last common ancestor of Proterosuchidae and Archosauria. Phil Senter (2005) defined it as the most exclusive clade containing ''Proterosuchus'' and Archosauria. Gauthier as part of the ''Phylonyms'' (2020) defined the clade as the last common ancestor of ''Chicken, Gallus'', ''Alligator'', and ''Proterosuchus'', and all its descendants. Archosauriforms are a branch of Archosauromorpha, archosauromorphs which originated in the Late Permian (roughly 252 million years ago) and persist to the present day as the two surviving archosaur groups: Crocodilia, crocodilians and Bird, birds. Archosauriforms present several traits historically ascribed to the group Archosauria. These include serrated teeth set in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesosuchus Browni
''Mesosuchus'' ("middle crocodile") is an extinct genus of basal rhynchosaur from early Middle Triassic (early Anisian stage) deposits of Eastern Cape, South Africa. It is known from the holotype SAM 5882, a partial skeleton, and from the paratypes SAM 6046, SAM 6536, SAM 7416 and SAM 7701 from the Aliwal North ''Euparkeria'' site. ''Mesosuchus'' is quite small, spanning around 30 cm in length. ''Mesosuchus'' was discovered and named by D. M. S. Watson in 1912. Discovery and naming Bones of ''Mesosuchus'' were first found by David Meredith Seares Watson in 1912 after examining a block of sandstone kept in a private collection of Alfred Brown. This block was found in the middle deposits of the Burgersdorp Formation, in the ''Cynognathus'' Assemblage Zone near the town of Aliwal North in the Cape Province of South Africa. The block of sandstone contained many intermingled partial skeletons of several small reptiles, and after careful sorting, Watson considered the u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burgersdorp Formation
The ''Cynognathus'' Assemblage Zone is a tetrapod biozone utilized in the Karoo Basin of South Africa. It is equivalent to the Burgersdorp Formation, the youngest lithostratigraphic formation in the Beaufort Group, which is part of the fossiliferous and geologically important Karoo Supergroup. The ''Cynognathus'' Assemblage Zone is the youngest of the eight biozones found in the Beaufort Group, and is considered to be late Early Triassic (Olenekian) to early Middle Triassic (Anisian) in age (around 247 Ma). The name of the biozone refers to '' Cynognathus crateronotus'', a large and carnivorous cynodont therapsid which occurs throughout the entire biozone. History The first fossils to be found in the Beaufort Group rocks that encompass the current eight biozones were discovered by Andrew Geddes Bain in 1856. However, it was not until 1892 that it was observed that the geological strata of the Beaufort Group could be differentiated based on their fossil taxa. The initial un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynognathus Assemblage Zone
The ''Cynognathus'' Assemblage Zone is a tetrapod biozone utilized in the Karoo Basin of South Africa. It is equivalent to the Burgersdorp Formation, the youngest Lithostratigraphy, lithostratigraphic Geological formation, formation in the Beaufort Group, which is part of the fossiliferous and geologically important Karoo Supergroup. The ''Cynognathus'' Assemblage Zone is the youngest of the eight biozones found in the Beaufort Group, and is considered to be late Early Triassic (Olenekian) to early Middle Triassic (Anisian) in age (around 247 Ma). The name of the biozone refers to ''Cynognathus, Cynognathus crateronotus'', a large and carnivorous cynodont therapsid which occurs throughout the entire biozone. History The first fossils to be found in the Beaufort Group rocks that encompass the current eight biozones were discovered by Andrew Geddes Bain in 1856. However, it was not until 1892 that it was observed that the geological strata of the Beaufort Group could be different ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pterosaur
Pterosaurs are 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 million 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 insectivores or predators of small vertebrates. Later pte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crown Group
In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. It is thus a way of defining a clade, a group consisting of a species and all its extant or extinct descendants. For example, Neornithes (birds) can be defined as a crown group, which includes the most recent common ancestor of all modern birds, and all of its extant or extinct descendants. The concept was developed by Willi Hennig, the formulator of phylogenetic systematics, as a way of classifying living organisms relative to their extinct relatives in his "Die Stammesgeschichte der Insekten", and the "crown" and "stem" group terminology was coined by R. P. S. Jefferies in 1979. Though formulated in the 1970s, the term was not commonly used until its reintroduction in 2000 by Graham Budd and Sören Jensen. Contents of the crow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Facultative Biped
A facultative biped is an animal that is capable of walking or running on two legs (bipedal), as a response to exceptional or discretionary (facultative) circumstances, while normally walking or running on four limbs or more. In contrast, obligate bipedalism is where walking or running on two legs is the primary method of locomotion. Facultative bipedalism has been observed in several families of lizards and multiple species of primates, including sifakas, capuchin monkeys, baboons, gibbons, gorillas, bonobos and chimpanzees. Several dinosaur and other prehistoric archosaur species are facultative bipeds, most notably ornithopods and marginocephalians, with some recorded examples within sauropodomorpha. Different facultatively bipedal species employ different types of bipedalism corresponding to the varying reasons they have for engaging in facultative bipedalism. In primates, bipedalism is often associated with food gathering and transport. In lizards, it has been debated whether ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Olenekian
In the geologic timescale, the Olenekian is an age (geology), age in the Early Triassic epoch (geology), epoch; in chronostratigraphy, it is a stage (stratigraphy), stage in the Lower Triassic series (stratigraphy), series. It spans the time between annum, Ma and Ma (million years ago). The Olenekian is sometimes divided into the Smithian and the Spathian subages or substages. The Olenekian follows the Induan and is followed by the Anisian (Middle Triassic). The Olenekian saw the deposition of a large part of the Buntsandstein in Europe. The Olenekian is roughly coeval with the regional Yongningzhenian Stage used in China. Stratigraphic definitions The Olenekian Stage was introduced into scientific literature by Russian stratigraphers in 1956. The stage is named after Olenëk in Siberia. Before the subdivision in Olenekian and Induan became established, both stages formed the Scythian Stage, which has since disappeared from the official timescale. The base of the Olenekian is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bipedalism
Bipedalism is a form of terrestrial locomotion where an animal moves by means of its two rear (or lower) Limb (anatomy), limbs or legs. An animal or machine that usually moves in a bipedal manner is known as a biped , meaning 'two feet' (from Latin ''bis'' 'double' and ''pes'' 'foot'). Types of bipedal movement include walking or running (a bipedal gait) and jumping, hopping. Several groups of modern species are habitual bipeds whose normal method of locomotion is two-legged. In the Triassic period some groups of archosaurs (a group that includes crocodiles and dinosaurs) developed bipedalism; among the dinosaurs, all the early forms and many later groups were habitual or exclusive bipeds; the birds are members of a clade of exclusively bipedal dinosaurs, the theropods. Within mammals, habitual bipedalism has evolved multiple times, with the Macropodidae, macropods, Dipodomyinae, kangaroo rats and mice, springhare, Hopping mouse, hopping mice, pangolins and hominin apes (austr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
High Walk
Crocodilia () is an Order (biology), order of semiaquatic, predatory reptiles that are known as crocodilians. They first appeared during the Late Cretaceous and are the closest living relatives of birds. Crocodilians are a type of crocodylomorph pseudosuchian, a subset of archosaurs that appeared about 235 million years ago and were the only survivors of the Triassic–Jurassic extinction event. While other crocodylomorph groups further survived the Cretaceous–Paleogene extinction event, notably sebecosuchians, only the crocodilians have survived into the Quaternary. The order includes the crocodile, true crocodiles (Family (biology), family Crocodylidae), the alligators and caimans (family Alligatoridae), and the gharial and false gharial (family Gavialidae). Although the term "crocodiles" is sometimes used to refer to all of these families, the term "crocodilians" is less ambiguous. Extant crocodilians have flat heads with long snouts and tails that are compressed on the si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
