Skulls of Tarbosaurus Bataar and Tyrannosaurus Rex Compared

Giant theropod dinosaurs from Asia and North America: Skulls of Tarbosaurus bataar and Tyrannosaurus rex compared Jørn H. Hurum and Karol Sabath Acta Palaeontologica Polonica 48 (2), 2003: 161-190 The skull of a newly prepared Tarbosaurus bataar is described bone by bone and compared with a disarticulated skull of Tyrannosaurus rex. Both Tarbosaurus bataar and Tyrannosaurus rex skulls are deep in lateral view. In dorsal view, the skull of T. rex is extremely broad posteriorly but narrows towards the snout; in Ta. bataar the skull is narrower (especially in its ventral part: the premaxilla, maxilla, jugal, and the quadrate complex), and the expansion of the posterior half of the skull is less abrupt. The slender snout of Ta. bataar is reminiscent of more primitive North American tyrannosaurids. The most obvious difference between T. rex and Ta. bataar is the doming of the nasal in Ta. bataar which is high between the lacrimals and is less attached to the other bones of the skull, than in most tyrannosaurids. This is because of a shift in the handling of the crushing bite in Ta. bataar . We propose a paleogeographically based division of the Tyrannosaurinae into the Asiatic forms (Tarbosaurus and possibly Alioramus) and North American forms (Daspletosaurus and Tyrannosaurus). The division is supported by differences in anatomy of the two groups: in Asiatic forms the nasal is excluded from the major series of bones participating in deflecting the impact in the upper jaw and the dentary-angular interlocking makes a more rigid lower jaw. Key words: Dinosauria, Theropoda, Tyrannosauridae, Tarbosaurus, Tyrannosaurus, skull, anatomy, Mongolia. Jørn H. Hurum [[email protected]], Paleontologisk Museum, Boks 1172 Blindern, N−0318 Oslo, Norway; Karol Sabath [[email protected]], Instytut Paleobiologii PAN, ul. Twarda 51/55, PL−00−818 Warszawa, Poland. This is an open-access article distributed under the terms of the Creative Commons Attribution License (for details please see creativecommons.org), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. Full text (1,737.2 kB) Powered by TCPDF (www.tcpdf.org).

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Tyrannosaurus Rex by Guy Belleranti
Name: ______________________________ Tyrannosaurus Rex By Guy Belleranti One of the most dangerous dinosaurs was the Tyrannosaurus rex. It looked like a huge lizard with sharp teeth. It lived over 60 million years ago. From nose to tail, T-rex was as long as a school bus. It was taller than a house. It weighed more than an airplane. T-rex’s head was as long as a kitchen table. T-rex was the biggest meat-eating dinosaur. It could eat hundreds of pounds of meat in one bite. Animals that eat meat have sharp teeth. T-rex had 60 of them! Some of the teeth were as big as bananas. When T-rex lost a tooth, it grew a new one. T-rex stood on two powerful legs. It also had two small arms. Its strong tail helped keep it from falling over. It might be fun to see a live Tyrannosaurus rex, but I wouldn’t want to meet one. Would you? Super Teacher Worksheets - www.superteacherworksheets.com Name: ______________________________ Tyrannosaurus Rex By Guy Belleranti 1. How many teeth did a Tyrannosaurus rex have? a. thirty b. sixteen c. sixty d. seventy 2. How long ago did Tyrannosaurus rex live? ________________________________________________________________ 3. What did Tyrannosaurus rex eat? a. leaves from tall trees b. other dinosaurs c. small insects d. people 4. A T-rex was as long as a ______________________________________. 5. A T-rex weighed as much as an _______________________________. 6. Which dinosaurs had sharp teeth? a. all dinosaurs b. dinosaurs that had tails c. dinosaurs that were big d.
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