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Anteosaur

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37-543: See Taxonomy Anteosaurs are a group of large, primitive carnivorous dinocephalian therapsids with large canines and incisors and short limbs, that are known from the Middle Permian of South Africa, Russia, China, and Brazil. Some grew very large, with skulls 50–80 centimetres (20–31 in) long, and were the largest predators of their time. They died out at the end of the Middle Permian, possibly as

74-655: A canine tooth and a further five canine teeth. So together the species contained fourteen upper teeth and twelve lower teeth of small size. Biarmosuchus tener was described by Chudinov in 1960 from the Ezhovo locality, Udmurtia, Russia. It was named for Bjarmaland , the name for the White Sea region in Old Norse literature . Biarmosuchus tener , known from two assorted skulls and post-cranial remains, including several complete skeletons. In 1999, Biarmosuchus tchudinovi ,

111-652: A facultative carnivore from an omnivore . Obligate or "true" carnivores are those whose diet requires nutrients found only in animal flesh in the wild. While obligate carnivores might be able to ingest small amounts of plant matter, they lack the necessary physiology required to fully digest it. Some obligate carnivorous mammals will ingest vegetation as an emetic , a food that upsets their stomachs, to self-induce vomiting. Obligate carnivores are diverse. The amphibian axolotl consumes mainly worms and larvae in its environment, but if necessary will consume algae. All wild felids , including feral domestic cats , require

148-534: A diet of primarily animal flesh and organs. Specifically, cats have high protein requirements and their metabolisms appear unable to synthesize essential nutrients such as retinol , arginine , taurine , and arachidonic acid ; thus, in nature, they must consume flesh to supply these nutrients. Characteristics commonly associated with carnivores include strength, speed, and keen senses for hunting, as well as teeth and claws for capturing and tearing prey. However, some carnivores do not hunt and are scavengers , lacking

185-402: A diprodontan dentition completely unlike that of any other mammal; and eutriconodonts like gobiconodontids and Jugulator , with a three-cusp anatomy which nevertheless functioned similarly to carnassials. Biarmosuchus Biarmosuchus is an extinct genus of biarmosuchian therapsids that lived around 267 mya during the Middle Permian period. Biarmosuchus was discovered in

222-511: A form of endosymbiosis , might have led to symbiogenesis that gave rise to eukaryotes and eukaryotic autotrophs such as green and red algae . The earliest predators were microorganisms , which engulfed and "swallowed" other smaller cells (i.e. phagocytosis ) and digested them internally . Because the earliest fossil record is poor, these first predators could date back anywhere between 1 and over 2.7  bya (billion years ago). The rise of eukaryotic cells at around 2.7 bya,

259-639: A great diversity of eutherian carnivores in the northern continents and Africa . In South America , sparassodonts were dominant, while Australia saw the presence of several marsupial predators, such as the dasyuromorphs and thylacoleonids . From the Miocene to the present, the dominant carnivorous mammals have been carnivoramorphs . Most carnivorous mammals, from dogs to deltatheridiums , share several dental adaptations, such as carnassialiforme teeth, long canines and even similar tooth replacement patterns. Most aberrant are thylacoleonids , with

296-406: A more traditional Linnaean arrangement, but includes the herbivorous forms under the superfamily Anteosauroidea as well. The "Titanosuchidae" here is equivalent to the " Tapinocephalia ". After Kammerer et al ., 2011. Carnivore A carnivore / ˈ k ɑːr n ɪ v ɔːr / , or meat-eater ( Latin , caro , genitive carnis , meaning meat or "flesh" and vorare meaning "to devour"),

333-544: A new species, was described by Ivakhnenko from the Sokol locality, Udmurtia, Russia. Biarmosuchus would seem to represent one of the most primitive of the Biarmosuchia, and could be taken as a good generalized model for the other, mostly later, forms. This genus is abundantly represented, but most of the specimens remain inadequately prepared and have not been used for an anatomical and functional analysis. Such details as

370-490: A result of the extinction of the herbivorous Tapinocephalia on which they may have fed. The Anteosauria are distinguished from the Tapinocephalia by several features, such as very large canines , cheek teeth with bulbous crowns , and an upturning of the premaxilla , so that the front of mouth curves strongly upwards. There is a tendency especially in more advanced forms such as Anteosaurus towards thickening of

407-409: Is an animal or plant whose nutrition and energy requirements are met by consumption of animal tissues (mainly muscle , fat and other soft tissues ) as food , whether through predation or scavenging . The technical term for mammals in the order Carnivora is carnivoran , and they are so-named because most member species in the group have a carnivorous diet, but the similarity of

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444-623: The Cambrian substrate revolution led to increased active predation among animals, likely triggering various evolutionary arms races that contributed to the rapid diversification during the Cambrian explosion . Radiodont arthropods , which produced the first apex predators such as Anomalocaris , quickly became the dominant carnivores of the Cambrian sea. After their decline due to the Cambrian-Ordovician extinction event ,

481-473: The Perm region of Russia . The first specimen was found in channel sandstone that was deposited by flood waters originating from the young Ural Mountains . Biarmosuchus was a medium-sized predator, similar in size to a large dog , grew up to 1.5 m (4 ft 11 in) to 2 m (6 ft 7 in) in length with a skull length 15 cm (5.9 in) (immature) to 21 cm (8.3 in). It

518-666: The giant panda , is nearly exclusively herbivorous . Dietary carnivory is not a distinguishing trait of the order . Many mammals with highly carnivorous diets are not members of the order Carnivora . Cetaceans , for example, all eat other animals, but are paradoxically members of the almost exclusively plant-eating hooved mammals . Animals that depend solely on animal flesh for their nutrient requirements in nature are called hypercarnivores or obligate carnivores , whilst those that also consume non-animal food are called mesocarnivores , or facultative carnivores , or omnivores (there are no clear distinctions). A carnivore at

555-423: The lobe-finned fish , became the dominant carnivores of freshwater wetlands formed by early land plants . Some of these fish became better adapted for breathing air and eventually giving rise to amphibian tetrapods . These early tetrapods were large semi-aquatic piscivores and riparian ambush predators that hunt terrestrial arthropods (mainly arachnids and myriopods ), and one group in particular,

592-531: The temnospondyls , became terrestrial apex predators that hunt other tetrapods. The dominance of temnospondyls around the wetland habitats throughout the Carboniferous forced other amphibians to evolve into amniotes that had adaptations that allowed them to live farther away from water bodies. These amniotes began to evolve both carnivory, which was a natural transition from insectivory requiring minimal adaptation; and herbivory , which took advantage of

629-423: The triconodontid Jugulator , the deltatheroidans and Cimolestes . Many of these, such as Repenomamus , Jugulator and Cimolestes , were among the largest mammals in their faunal assemblages, capable of attacking dinosaurs. In the early-to-mid-Cenozoic, the dominant predator forms were mammals: hyaenodonts , oxyaenids , entelodonts , ptolemaiidans , arctocyonids and mesonychians , representing

666-480: The Russian dinocephalian assemblages indicate environments tied to water, and Boonstra considered that the roughly contemporary Anteosaurus was a slinking crocodile-like semi-aquatic form. The long tail, weak limbs, and sprawling posture do indeed suggest some sort of crocodile-like existence. However, the thickened skull-roof indicates that these animals were quite able to get about on land, if they were to practice

703-527: The Tapinocehalia, are part of the first major evolutionary radiation of the Therapsida (Rubidge & Sidor 2001). So far, little work has been done on detailed phylogenetic relationships between the various taxa . The stance of a typical anteosaur, such as Titanophoneus , was primitive. Rather than the limbs being drawn in under the body, the stance was more sprawling. Olson (1962) notes that

740-452: The abundance of coal forest foliage but in contrast required a complex set of adaptations that was necessary for digesting on the cellulose - and lignin -rich plant materials. After the Carboniferous rainforest collapse , both synapsid and sauropsid amniotes quickly gained dominance as the top terrestrial animals during the subsequent Permian period. Some scientists assert that sphenacodontoid synapsids such as Dimetrodon "were

777-419: The bones of the top of the skull, indicating head-butting behavior. There is a large canal for the pineal organ (third eye); probably tied in with the animal's diurnal and seasonal cycles. The shoulder girdle is fairly light, with a narrow interclavicle, clavicle, and scapular blade. The femur (thigh bone) is slender and curved. These were, despite their size, probably quite agile animals. The limbs are short and

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814-473: The configuration of the palatines are unknown, as well as numerous characteristics of the postcranial skeleton. It may be that several taxa are represented, but in the present state of our knowledge, it is not possible to define them. Biarmosaurus antecessor is based on a larger (206 mm as opposed to 153 mm) skull than the holotype, representing a mature individual. This animal is similar in size to Phthinosuchus , but opinions differ as to how distinct

851-468: The first terrestrial vertebrate to develop the curved, serrated teeth that enable a predator to eat prey much larger than itself". In the Mesozoic , some theropod dinosaurs such as Tyrannosaurus rex are thought probably to have been obligate carnivores. Though the theropods were the larger carnivores, several carnivorous mammal groups were already present. Most notable are the gobiconodontids ,

888-400: The most highly predaceous of all synapsids (Sennikov, 1996), potential prey included the bull-sized armored pareiasaurs (Lee, 1997) and enormous tapinocephalid dinocephalians (Rubidge, 1995). The large anteosaurs were efficient predators, more specialized than earlier and more primitive biarmosuchid and eotitanosuchid carnivorous therapsids, as the temporal opening behind the eye socket

925-496: The name of the order and the name of the diet causes confusion. Many but not all carnivorans are meat eaters; a few, such as the large and small cats ( Felidae ) are obligate carnivores (see below). Other classes of carnivore are highly variable. The ursids , for example: while the Arctic polar bear eats meat almost exclusively (more than 90% of its diet is meat), almost all other bear species are omnivorous , and one species,

962-596: The niches of large carnivores were taken over by nautiloid cephalopods such as Cameroceras and later eurypterids such as Jaekelopterus during the Ordovician and Silurian periods. The first vertebrate carnivores appeared after the evolution of jawed fish , especially armored placoderms such as the massive Dunkleosteus . The dominance of placoderms in the Devonian ocean forced other fish to venture into other niches, and one clade of bony fish ,

999-468: The percentage of meat in their diet. The diet of a hypercarnivore consists of more than 70% meat, that of a mesocarnivore 30–70%, and that of a hypocarnivore less than 30%, with the balance consisting of non-animal foods, such as fruits , other plant material, or fungi . Omnivores also consume both animal and non-animal food, and apart from their more general definition, there is no clearly defined ratio of plant vs. animal material that distinguishes

1036-555: The physical characteristics to bring down prey; in addition, most hunting carnivores will scavenge when the opportunity arises. Carnivores have comparatively short digestive systems, as they are not required to break down the tough cellulose found in plants. Many hunting animals have evolved eyes facing forward, enabling depth perception. This is almost universal among mammalian predators, while most reptile and amphibian predators have eyes facing sideways. Predation (the eating of one living organism by another for nutrition ) predates

1073-402: The rise of commonly recognized carnivores by hundreds of millions (perhaps billions) of years. It began with single-celled organisms that phagocytozed and digested other cells, and later evolved into multicellular organisms with specialized cells that were dedicated to breaking down other organisms. Incomplete digestion of the prey organisms, some of which survived inside the predators in

1110-663: The rise of multicellular organisms at about 2 bya, and the rise of motile predators (around 600 Mya – 2 bya, probably around 1 bya) have all been attributed to early predatory behavior, and many very early remains show evidence of boreholes or other markings attributed to small predator species. The sudden disappearance of the precambrian Ediacaran biota at the end-Ediacaran extinction , who were mostly bottom-dwelling filter feeders and grazers , has been hypothetized to be partly caused by increased predation by newer animals with hardened skeleton and mouthparts. The degradation of seafloor microbial mats due to

1147-454: The skull is long, narrow, and heavy. The tail is very long in at least some genera. The early Russian (Boonstra 1972) and Chinese (Rubidge & Sidor 2001) anteosaurs are generally considered the most primitive of the dinocephalians, although it has also been suggested (Kemp, 1982, King 1988) that the estemmenosuchids are more basal . They have featured in common with pelycosaurs (Carroll 1988) and Biarmosuchians (Chudinov 1965), and, with

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1184-566: The term "Anteosauria" and synonymised the families Brithopodidae and Anteosauridae. In 2010, Christian Kammerer published a re-evaluation of anteosaurian relationships. The cladogram below follows an updated (2012) version of Kammerer's analysis by Juan Carolos Cisneros and colleagues. Biarmosuchus Estemmenosuchus Ulemosaurus Tapinocaninus Archaeosyodon Sinophoneus Titanophoneus adamanteus Titanophoneus potens Anteosaurus Pampaphoneus Notosyodon Syodon Australosyodon The group

1221-1007: The top of the food chain (adults not preyed upon by other animals) is termed an apex predator , regardless of whether it is an obligate or facultative carnivore. In captivity or domestic settings, obligate carnivores like cats and crocodiles can, in principle, get all their required nutrients from processed food made from plant and synthetic sources. Outside the animal kingdom, there are several genera containing carnivorous plants (predominantly insectivores) and several phyla containing carnivorous fungi (preying mostly on microscopic invertebrates , such as nematodes , amoebae , and springtails ). Carnivores are sometimes characterized by their type of prey . For example, animals that eat mainly insects and similar terrestrial arthropods are called insectivores , while those that eat mainly soft-bodied invertebrates are called vermivores . Those that eat mainly fish are called piscivores . Carnivores may alternatively be classified according to

1258-425: The typically dinocephalian head-butting behavior. All other head-butters, pachycephalosaurian dinosaurs , titanothere ungulates, and goats were or are completely terrestrial. Perhaps these animals spent some time in the water but were active on land during the mating season, and probably quite able to get about on land to hunt for prey. Anteosaurs were evolved to prey on particularly large animals and were among

1295-402: Was a lightly built, probably agile animal that would have fed on smaller tetrapods. Their legs are quite long, and the animals were probably quite agile in spite of their size. A large opening for the eye and a small temple opening common in primitive stem-mammals, this lends to a weak bite but how it ate is pure speculation. The teeth contained eight small incisors on the palate , followed by

1332-408: Was larger, indicating a greater muscle mass available for closing the lower jaw. Large pterygoid flanges indicate a well-developed Kinetic-Inertial system in anteosaurs, and increased vertical alignment of the temporalis muscles suggests an expanded Static-Pressure component of the bite cycle. James Hopson and Herbert Barghusen in 1986 provided the first cladistic study of the Therapsida. They used

1369-589: Was originally defined as a superfamily by L. D. Boonstra in 1962 to include the families Brithopodidae and Anteosauridae . Gillian King in a 1988 review of the Anomodontia (including the Dinocephalia - however the view that the Dinocephalia are a subset of the Anomodontia is no longer held) as part of Gutsav Fischer Verlag's ongoing Encyclopedia of Paleoherpetology series of volumes, uses

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