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The feeding behaviour of ''Tyrannosaurus rex'' has been studied extensively. The well known attributes of ''T. rex'' (its jaws, legs and overall body design) are often interpreted to be indicative of either a predatory or scavenging lifestyle, and as such the biomechanics, feeding strategies and diet of ''Tyrannosaurus'' have been subject to much research and debate. ==Feeding== Like other tyrannosaurids, ''Tyrannosaurus rex'' is known to have been carnivorous due primarily to the shape of the teeth. A study conducted by Miriam Reichel of the University of Alberta found that the tyrannosaurs' dissimilar teeth had different uses depending on their size, placement, serrated edge and angle in the mouth. While the teeth at the front were specially designed for gripping and pulling, the teeth at the side of the jaw were meant to puncture and the teeth at the back were specialized to both slice pieces from its prey and force it to its throat. She also proposed that the banana-shaped teeth of ''Tyrannosaurus rex were designed to withstand the strain of violently struggling prey which would otherwise snap teeth that were sharp, flat and knife-like. A study by Emily J. Rayfield from the University of Bristol further supported that ''Tyrannosaurus'' used the puncture and pull feeding strategy, where the ''Tyrannosaurus ''would startle its prey with a powerful bite and then drag its teeth back through its prey's flesh and bone. The study found that ''Tyrannosaurus'' had a bony skull that is adapted to withstand biting and shearing forces; with strong nasal bones that helped it withstand compression and shearing stresses and lacrimal bones that enabled the skull to withstand a variety of stresses. Her study also found that the maxilla jugal sutures found in ''Tyrannosaurus'' cheeks acted as shock absorbers. These joints had soft tissue that absorbed some of the stresses encountered when biting. This trades some of the skull's durability in return for enabling it to better protect the surrounding the skull bones from damage when biting. The study also found that the skull redirected much of the strain from biting to the ''Tyrannosaurus'' skull's robust nasal bones. In his 2013 lecture, Thomas Holtz Jr stated that fused nasal bones and the presence of incisors were some of the unique traits of ''Tyrannosaurus'' and its relatives. He stated that most reptiles do not have incisors, having teeth at the front of the jaw that are similar to the one's at the rest of the jaw, and suggested that these incisors were used to scrape the meat from bones. He also stated that ''Tyrannosaurus'' teeth were different from previous theropods because they were thick from side to side and while the teeth of many other theropods had roots just as long as the crown, the teeth of ''Tyrannosaurus'' had roots that were twice as long as the crowns. He further states that the teeth of ''Tyrannosaurus'' didn't look like they were for cutting but instead they looked like they were for pulverizing, crushing and piercing.〔 In 2012, a study of the jaws of ''Tyrannosaurus'' by biomechanical expert Karl Bates of the University of Liverpool and paleontologist Peter Falkingham of the Royal Veterinary College, London, and Brown University was published in ''Biology Letters''. Bates and Falkingham used computer modeling to reconstruct ''Tyrannosaurus skull and relevant jaw musculature based on anatomical research on crocodilians and birds. From these reconstructions, it was estimated that ''Tyrannosaurus'' was likely capable of exerting a bite force of between 35,000 to 57,000 newtons ( 7,860-12,800 pounds or 3.93-6.4 short tons), around ten times as great as the strongest alligator bite. However, other, heavier predators, such as the crocodilian ''Deinosuchus'' and the giant shark ''Megalodon'' surpassed this bite in strength having bite forces of 11.5 short tons and 20.5 short tons respectively. The study also revealed that a juvenile ''Tyrannosaurus'' had a bite force of no more than 880 pounds of force or 3,914.43 newtons, and that the bite became more powerful as the animal matured. This also supports the theory that juvenile ''Tyrannosaurus'' hunted different prey in a form of niche partitioning so as to avoid competition with the adults〔(), Bates, K.T & Falkingham P.L. (2012). Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics. Biological Letters. 〕〔http://news.nationalgeographic.com/news/2012/120228-t-rex-bite-bates-science-biology-letters-dinosaurs/〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「 The feeding behaviour of ''Tyrannosaurus rex'' has been studied extensively. The well known attributes of ''T. rex'' (its jaws, legs and overall body design) are often interpreted to be indicative of either a predatory or scavenging lifestyle, and as such the biomechanics, feeding strategies and diet of ''Tyrannosaurus'' have been subject to much research and debate.==Feeding==Like other tyrannosaurids, ''Tyrannosaurus rex'' is known to have been carnivorous due primarily to the shape of the teeth. A study conducted by Miriam Reichel of the University of Alberta found that the tyrannosaurs' dissimilar teeth had different uses depending on their size, placement, serrated edge and angle in the mouth. While the teeth at the front were specially designed for gripping and pulling, the teeth at the side of the jaw were meant to puncture and the teeth at the back were specialized to both slice pieces from its prey and force it to its throat. She also proposed that the banana-shaped teeth of ''Tyrannosaurus rex were designed to withstand the strain of violently struggling prey which would otherwise snap teeth that were sharp, flat and knife-like.A study by Emily J. Rayfield from the University of Bristol further supported that ''Tyrannosaurus'' used the puncture and pull feeding strategy, where the ''Tyrannosaurus ''would startle its prey with a powerful bite and then drag its teeth back through its prey's flesh and bone. The study found that ''Tyrannosaurus'' had a bony skull that is adapted to withstand biting and shearing forces; with strong nasal bones that helped it withstand compression and shearing stresses and lacrimal bones that enabled the skull to withstand a variety of stresses. Her study also found that the maxilla jugal sutures found in ''Tyrannosaurus'' cheeks acted as shock absorbers. These joints had soft tissue that absorbed some of the stresses encountered when biting. This trades some of the skull's durability in return for enabling it to better protect the surrounding the skull bones from damage when biting. The study also found that the skull redirected much of the strain from biting to the ''Tyrannosaurus'' skull's robust nasal bones.In his 2013 lecture, Thomas Holtz Jr stated that fused nasal bones and the presence of incisors were some of the unique traits of ''Tyrannosaurus'' and its relatives. He stated that most reptiles do not have incisors, having teeth at the front of the jaw that are similar to the one's at the rest of the jaw, and suggested that these incisors were used to scrape the meat from bones. He also stated that ''Tyrannosaurus'' teeth were different from previous theropods because they were thick from side to side and while the teeth of many other theropods had roots just as long as the crown, the teeth of ''Tyrannosaurus'' had roots that were twice as long as the crowns. He further states that the teeth of ''Tyrannosaurus'' didn't look like they were for cutting but instead they looked like they were for pulverizing, crushing and piercing.In 2012, a study of the jaws of ''Tyrannosaurus'' by biomechanical expert Karl Bates of the University of Liverpool and paleontologist Peter Falkingham of the Royal Veterinary College, London, and Brown University was published in ''Biology Letters''. Bates and Falkingham used computer modeling to reconstruct ''Tyrannosaurus skull and relevant jaw musculature based on anatomical research on crocodilians and birds. From these reconstructions, it was estimated that ''Tyrannosaurus'' was likely capable of exerting a bite force of between 35,000 to 57,000 newtons ( 7,860-12,800 pounds or 3.93-6.4 short tons), around ten times as great as the strongest alligator bite. However, other, heavier predators, such as the crocodilian ''Deinosuchus'' and the giant shark ''Megalodon'' surpassed this bite in strength having bite forces of 11.5 short tons and 20.5 short tons respectively. The study also revealed that a juvenile ''Tyrannosaurus'' had a bite force of no more than 880 pounds of force or 3,914.43 newtons, and that the bite became more powerful as the animal matured. This also supports the theory that juvenile ''Tyrannosaurus'' hunted different prey in a form of niche partitioning so as to avoid competition with the adults(), Bates, K.T & Falkingham P.L. (2012). Estimating maximum bite performance in Tyrannosaurus rex using multi-body dynamics. Biological Letters. http://news.nationalgeographic.com/news/2012/120228-t-rex-bite-bates-science-biology-letters-dinosaurs/」の詳細全文を読む スポンサード リンク
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