Dinosaurs
Creatures from another age
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Bambiraptor by Moondawg
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The Bambiraptor skeleton was discovered in 1995 by 14-year-old fossil hunter Wes Linster, who was looking for dinosaur bones with his parents near Glacier National Park in Montana. Linster told Time Magazine that he uncovered the skeleton on a tall hill and was amazed at his discovery. "I bolted down the hill to get my mom because I knew I shouldn't be messing with it", he said. The bones that Linster discovered on that hilltop led to the excavation of a skeleton that was approximately 95 percent complete. Because of its completeness Florida Paleontology Institute Director Martin Shugar compared it to the 'Rosetta Stone' that enabled archaeologists to translate Egyptian hieroglyphics. Yale paleontologist John Ostrom, who reintroduced the theory of bird evolution from dinosaurs after his 1964 discovery of Deinonychus in Wyoming, agreed, calling the specimen a "jewel", and telling reporters that the completeness and undistorted qualities of the bones should help scientists further understand the dinosaur-bird link. The specimen is currently housed at the American Museum of Natural History, New York.
During the conference where Bambiraptor was first introduced, the dinosaur reconstruction specialist Brian Cooley portrayed Bambiraptor as having feathers, despite the fact that no feathers were found with the fossil itself. His decision was influenced by the fact that because Bambiraptor within a cladistic analysis was a member of a group, Paraves, that contained feathered true birds and that was the sister taxon of Oviraptorosauria, a group that also had feathered forms (e.g. Caudipteryx), Bambiraptor most likely had feathers too due to phylogenetic bracketing. Most paleontologists support Cooley's view, and subsequent discoveries confirmed that small dromaeosaurid dinosaurs like Bambiraptor were fully covered in feathers.
Research done at Lamar State College in Orange, Texas has indicated that Bambiraptor may have had opposable front claws and a forelimb maneuverability that could reach its mouth. This would have given the animal the ability to "hold" food in its front limbs and place it in its mouth, in a similar manner to some modern-day small mammals.
Bambiraptor skull in the Oxford University Museum of Natural History.Bambiraptor had a brain size in the lower range of modern birds. Because of its enlarged cerebellum, which may indicate higher agility and higher intelligence than other dromaeosaurs, David A. Burnham has hypothesized that Bambiraptor feinbergi may have been arboreal. Life in the trees may have required evolutionary pressure that resulted in a larger brain. Burnham also offers an alternative hypothesis that a larger brain could be selected for as a result of hunting more agile prey items such as lizards and mammals. Bambiraptor had the largest brain for its size of any dinosaur yet discovered, although the brain size may be due to its age, because juvenile animals tend to have larger brain-to-body ratios compared to adults. It also had very long arms and a well-developed wishbone.
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Garudimimus by Moondawg
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Garudimimus ("Garuda mimic") is a basal member of Ornithomimosauria, known from single specimen discovered from Upper Cretaceous sediments of Mongolia.
Previously it was thought that this primitive member of Ornithomimosauria possessed a horn at the top of the skull. However, recent studies have shown that this "horn" was simply a misplaced skull bone. In 1981, Rinchen Barsbold placed it in its own family, Garudimimidae.
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Compsognathus by Moondawg
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Compsognathus (pronounced kompsos"elegant", "refined" or "dainty", and gnathos"jaw") was a small, bipedal, carnivorous theropod dinosaur.
The animal was the size of a turkey and lived around 150 million years ago, the early Tithonian stage of the late Jurassic Period, in what is now Europe.
Paleontologists have found two well-preserved fossils, one in Germany in the 1850s and the second in France more than a century later.
Many popular presentations still describe Compsognathus as a "chicken-sized" dinosaur because of the small size of the German specimen, which is now believed to be a juvenile form of the larger French specimen. Compsognathus is one of the few dinosaurs for which the diet is known with certainty: the remains of small, agile lizards are preserved in the bellies of both specimens. Teeth discovered in Portugal may be further fossil remains of the genus.
Although not recognized as such at the time of its discovery, Compsognathus is the first dinosaur known from a reasonably complete skeleton. Today, C. longipes is the only recognized species, although the larger specimen discovered in France in the 1970s was once thought to belong to a separate species, C. corallestris. Until the 1980s and 1990s, Compsognathus was the smallest known dinosaur and the closest supposed relative of the early bird Archaeopteryx. Thus, the genus is one of the few dinosaur genera to be well known outside of paleontological circles.
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Vulcanodon by Moondawg
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Vulcanodon (meaning "volcano tooth") was a relatively small, early sauropod dinosaur genus from the Early Jurassic.
It was about 6.5 meters (20 feet) long. Vulcanodon ate plants and lived in southern Africa. The type species, V. karibaensis, was formally described by Michael A. Raath of the University of the Witwatersrand, Johannesburg, in 1972.
It was originally believed to be a prosauropod because of the knife shaped teeth found near its fossils, which fit in with the idea that prosauropods were omnivorous, but scientists now know that the teeth belonged to an unidentified theropod that scavenged on the Vulcanodon's carcass.
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Microraptor by Moondawg
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Microraptor had two sets of wings, on both its fore- and hind legs. The long feathers on the legs of Microraptor were true flight feathers as seen in modern birds, with asymmetrical vanes on the arm, leg, and tail feathers. As in bird wings, Microraptor had both primary (anchored to the hand) and secondary (anchored to the arm) flight feathers. This standard wing pattern was mirrored on the hind legs, with flight feathers anchored to the upper foot bones as well as the upper and lower leg. It had been proposed by Chinese scientists that the animal glided, and probably lived in trees, pointing to the fact that wings anchored to the feet of Microraptor would have hindered their ability to run on the ground, and suggest that all primitive dromaeosaurids may have been arboreal.
Sankar Chatterjee determined in 2005 that, in order for the creature to glide or fly, the wings must have been split-level (like a biplane) and not overlayed (like a dragonfly), and that the latter posture would have been anatomically impossible. Using this biplane model, Chatterjee was able to calculate possible methods of gliding, and determined that Microraptor most likely employed a phugoid style of gliding--launching itself from a perch, the animal would have swooped downward in a deep 'U' shaped curve and then lifted again to land on another tree. The feathers not directly employed in the biplane wing structure, like those on the tibia and the tail, could have been used to control drag and alter the flight path, trajectory, etc. The orientation of the hind wings would also have helped the animal control its gliding flight. Chatterjee also used computer algorithms that test animal flight capacity to test whether or not Microraptor was capable of true, powered flight, in addition to passive gliding. The resulting data showed that Microraptor did have the requirements to sustain level powered flight, so it is theoretically possible that the animal flew on occasion in addition to gliding.
Some paleontologists have suggested that feathered dinosaurs used their wings to parachute from trees, possibly in order to attack or ambush prey on the ground, as a precursor to gliding or true flight. In their 2007 study, Chatterjee and Templin tested this hypothesis as well, and found that the combined wing surface of Microraptor was too narrow to successfully parachute to the ground without injury from any significant height. However, the authors did leave open the possibility that Microraptor could have parachuted short distances, as between closely spaced tree branches.
Chatterjee and Templin also ruled out the possibility of a ground-based takeoff. Microraptor lacked the necessary adaptations in its shoulder joint to lift its front wings high enough vertically to generate lift from the ground, and the authors argued that a ground-based takeoff would have damaged flight feathers on the feet. This leaves only the possibility of launching from an elevated perch, and the authors noted that even modern birds do not need to use excess power when launching from trees, but use the downward-swooping technique they found in Microraptor.
The unique wing arrangement found in Microraptor raised the question of its importance to the origin of flight in modern birds--did avian flight go through a four-winged stage, or were four-winged gliders like Microraptor an evolutionary side-branch that did not leave descendants? As early as 1915, some scientists had argued that the evolution of bird flight may have gone through a four-winged (or tetrapteryx) stage. Chatterjee and Templin did not take a strong stance on this possibility, noting that both a conventional interpretation and a tetrapteryx stage are equally possible. However, based on the presence of unusually long leg feathers in various feathered dinosaurs, Archaeopteryx, and some modern birds such as raptors, as well as the discovery of Pedopenna (another dinosaur with long primary feathers on its feet), the authors argued that the current body of evidence, both from morphology and phylogeny, suggests that bird flight did shift at some point from shared limb dominance to front-limb dominance, and that all modern birds may have evolved from four-winged ancestors, or at least ancestors with unusually long leg feathers relative to the modern configuration.
The naming of Microraptor is controversial, because of the unusual circumstances of its first description. The first specimen to be described was part of a chimeric specimen , a patchwork of unrelated feathered dinosaur species assembled from multiple specimens in China and smuggled to the USA for sale. After the forgery was revealed by Xu Xing of Beijing's Institute of Vertebrate Paleontology and Paleoanthropology, Storrs L. Olson, curator of birds in the National Museum of Natural History of the Smithsonian Institution, published a description of the tail in an obscure journal, giving it the name Archaeoraptor liaoningensis in an attempt to remove the name from the paleornithological record by assigning it to the part least likely to be a bird. However, Xu had discovered the remainder of the specimen from which the tail had been taken and published a description of it later that year, giving it the name Microraptor zhaoianus.
Since the two names designate the same individual as the type specimen, Microraptor zhaoianus is a junior objective synonym of Archaeoraptor liaoningensis and the latter, if valid, has priority. So, according to some interpretations of the International Code of Zoological Nomenclature, the valid name for this dinosaur probably is Archaeoraptor liaoningensis Olson 2000. However, there is some doubt whether Olson in fact succeeded in meeting all the formal requirements for establishing a new taxon. Most paleontologists are unwilling to use the name Archaeoraptor regardless of the precise legal status of the name. This is firstly because that name is strongly associated with the fraud and the National Geographic scandal and secondly because they view Olson's use of the name as attempted nomenclatural sabotage and do not want to support it. The name Microraptor zhaoianus Xu et al., 2000 has therefore almost attained universal currency.
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Gorgosaurus by Moondawg
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Like most known tyrannosaurids, Gorgosaurus was a multi-ton bipedal predator equipped with dozens of large, sharp teeth; it also bore tiny two-fingered forelimbs typical of its close relatives. Although relatively large for a theropod, Gorgosaurus was much smaller than its more famous relative Tyrannosaurus.
Gorgosaurus (pronounced GOR-go-SAWR-us; meaning "fierce lizard") is a genus of tyrannosaurid theropod dinosaur that lived in western North America during the Late Cretaceous Period, between about 77 and 74 million years ago. Fossil remains have been found in the Canadian province of Alberta and possibly the U.S. state of Montana. Paleontologists recognize only the type species, G. libratus, although other species have been erroneously referred to the genus.
Like most known tyrannosaurids, Gorgosaurus was a bipedal predator weighing more than a metric ton as an adult; dozens of large, sharp teeth lined its jaws, while its two-fingered forelimbs were comparatively small. Gorgosaurus was most closely related to Albertosaurus, and more distantly related to the larger Tyrannosaurus. Gorgosaurus and Albertosaurus are extremely similar, distinguished mainly by subtle differences in the teeth and skull bones. Some experts consider G. libratus to be a species of Albertosaurus; this would make Gorgosaurus a junior synonym of that genus.
Gorgosaurus lived in a lush floodplain environment along the edge of an inland sea. An apex predator, it was at the top of the food chain, preying upon abundant ceratopsids and hadrosaurs. In some areas, Gorgosaurus coexisted with another tyrannosaurid, Daspletosaurus. Though these animals were roughly the same size, there is some evidence of niche differentiation between the two. Gorgosaurus is the best-represented tyrannosaurid in the fossil record, known from dozens of specimens. These plentiful remains have allowed scientists to investigate its ontogeny, life history and other aspects of its biology.
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Bernissartia by Moondawg
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Bernissartia is one of the smallest crocodylians that ever lived. It resembled modern species and was probably semi-aquatic. It had long, pointed teeth at the front of the jaws would have been of use in catching fish, while the broad and flat teeth at the back of its jaws would have facilitated crushing hard food, such as shellfish and possibly bones. It lived during the early Cretaceous in modern day England and Belgium.
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Muraenosaurus by Moondawg
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Muraenosaurus ('moray eel lizard') is an extinct genus of sauropterygian reptile belonging to the plesiosaur order. It lived in Late Jurassic Europe, and grew to 30 feet (8 m) long. Half of its length was its neck, which consisted of 44 vertebrae. Its skull was small.
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Podokesaurus by Moondawg
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The only fossils of Podokesaurus holyokensis (the full name given by Talbot) were recovered in 1911 by Mount Holyoke College professor of geology and geography, Mignon Talbot from a boulder near to the college. It was formally described that year based on a poorly preserved, incomplete fossil skeleton.
This fossil evidence suggests that it may not be a distinct genus but in fact a species of Coelophysis, standing 1 m (3 ft) long and 0.3 m (1 ft) high, and weighing 4 kg (10 lb). The matter is complicated because all the original fossil evidence for Podokesaurus holyokensis was destroyed in a fire and only casts remain in The Division of Paleontology at the American Museum of Natural History, New York.
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Barapasaurus by Moondawg
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Barapasaurus is curious because it is the earliest known sauropod, dating from the early Jurassic Period — more precisely the Toarcian age, about 189.6 to 176.5 million years ago. This is evident in the unspecialized nature of its form. Later sauropods like Brachiosaurus developed their own ecological niche and feeding strategies. However, Barapasaurus was something of an "all-purpose" dinosaur. For example, later sauropods developed hollow vertebrae, as a weight-saving measure. Barapasaurus vertebrae, on the other hand, were almost solid, with only the earliest hints of hollowing. (See also: Camarasaurus.)
Despite its early place in dinosaur history, Barapasaurus reached a length of about 18 metres (60 feet), and weighed about 48 tones (53 tons). Its height to the hip was approximately 5.5 metres (18 feet).
Like all sauropods, Barapasaurus was a herbivore. However, no skull has yet been recovered and so its exact diet has not been determined. A few lone teeth are known but not sufficient to make judgments on diet.
Barapasaurus is also important because, although its remains were found in India, it is very similar to other samples found in East Africa. From this we can conclude that during the early Jurassic period, these two land masses were still connected or at least only recently divorced.
Barapasaurus is included in Vulcanodontidae rather than Cetiosauridae, another family in Sauropoda. This classification is unconfirmed since insufficient work has been done on the skeletons. The description is justified by the narrow sacrum (a boxlike structure of the hip), which is a characteristic of vulcanodontids. However, the dorsal vertebrae display features shared with Cetiosauridae, such as a high neural arch above the vertebral foramen.
Currently the only known species is the original B. tagorsi.
The first bones of Barapasaurus were recovered in India in 1960. However, it was not until 1975 that this recovery was made the type specimen, and the official description published by Jain, Kutty, Roy-Chowdhury and Chatterjee of Calcutta.
Since then, five additional skeletons have been recovered from the Godavari Valley in southern India. However, none of these included the skull or feet. The remainder of the skeleton is known, so it is theoretically the best-known of the early Jurassic sauropods. Unfortunately, little work has yet been published regarding these discoveries.
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Aegyptosaurus by Moondawg
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Aegyptosaurus meaning 'Egypt’s lizard', where it was discovered is a genus of dinosaur believed to have lived in what is now Africa, around 95 million years ago, during the mid- and late-Cretaceous Period.
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Pistosaurus by Moondawg
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Pistosaurus longaevus is an extinct genus of aquatic sauropterygian reptile belonging to the plesiosaur order.
PISTOSAURUS
(pronounced PIST-oh-SAWR-us) Pistosaurus was a nothosaur, a reptile with flipper-like limbs that lived both on land and in the water. It was about 10 feet (3 m) long with a very long neck, four long, paddle-shaped flippers, a streamlined body, and many sharp, pointed teeth in long jaws. Fossils have been found in France and Germany. It lived during the mid-Triassic period. It was not dinosaur
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Parasuchus by Moondawg
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Parasuchus was a genus of several crocodile-like semi-aquatic animals that lived in the Late Triassic, specifically the earlier Late Carnian period. The reptiles lived throughout Europe, North America, and North Africa.
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Siamotyrannus by Moondawg
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Siamotyrannus isanensis (meaning "Siamese Tyrant") was a carnosaur from the Early Cretaceous. Its fossils, the pelvis and vertebrae were found in Thailand. . As evidenced by its name, it was originally thought to be a tyrannosauroid, though it is quite small at 6.5m in length. It has also been suggested that it may be an allosaurid or sinraptorid.
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Rainforest T-Rex by JohnT
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The T-Rex loves plenty of fresh meat, and needs the strongest fence to hold it. This Rainforest Tyrannosaurus Rex uses the same graphics as the in-game T-Rex, but with a change in habitat and object preferences, as well as different animal info. Since this T-Rex links directly to the graphics of the in-game T-Rex, you must have either DD or CC to use it. The in-game T-Rex will still be available in addition to this T-Rex.
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Variraptor by JohnT
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As a cousin of the Velociraptor, your zoo guests will enjoy this colorful but deadly animal.
You must have either DD or CC to use this dinosaur.
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