page_title: Diplodocus
section_title: Paleobiology
hierarchical_section_title: Diplodocus / Paleobiology
caption_attribution_description: Català: Diplodocus hallorum (antigament conegut com a Seismosaurus),. Deutsch: Seismosaurus hallorum, Lebendrekonstruktion. English: "Seismosaurus". Seismo (Diplodocus hallorum). Diplodocus. D. hallorum (formerly known as Seismosaurus). Diplodocus was one of the longest dinosaurs. Español: D. hallorum. Français&#160;: Diplodocus hallorum. Magyar: D. hallorum (korábbi nevén Seismosaurus). 日本語: D. hallorum （ディプロドクス・ハロルム［シノニム：セイスモサウルス・ハロルム］）の生態復元想像図. Polski: Sejsmozaur. Русский: Diplodocus hallorum — «сейсмозавр», длина до 36 м. Kiswahili: Uchoraji wa Diplodocus. 中文: Diplodocus hallorum，原為地震龍.
context_page_description: Diplodocus is a genus of diplodocid sauropod dinosaurs whose fossils were first discovered in 1877 by S. W. Williston. The generic name, coined by Othniel Charles Marsh in 1878, is a neo-Latin term derived from Greek διπλός "double" and δοκός "beam", in reference to the double-beamed chevron bones located in the underside of the tail, which were then considered unique.
  This genus of dinosaurs lived in what is now mid-western North America at the end of the Jurassic period. Diplodocus is one of the more common dinosaur fossils found in the middle to upper Morrison Formation, between about 154 and 152 million years ago, during the late Kimmeridgian age. The Morrison Formation records an environment and time dominated by gigantic sauropod dinosaurs, such as Apatosaurus, Barosaurus, Brachiosaurus, Brontosaurus, and Camarasaurus. Its great size may have been a deterrent to the predators Allosaurus and Ceratosaurus: their remains have been found in the same strata, which suggests that they coexisted with Diplodocus.
  Diplodocus is among the most easily identifiable dinosaurs, with its typical sauropod shape, long neck and tail, and four sturdy legs.
context_section_description: Due to a wealth of skeletal remains, Diplodocus is one of the best-studied dinosaurs. Many aspects of its lifestyle have been subjects of various theories over the years. Comparisons between the scleral rings of diplodocines and modern birds and reptiles suggest that they may have been cathemeral, active throughout the day at short intervals.
  Marsh and then Hatcher assumed that the animal was aquatic, because of the position of its nasal openings at the apex of the cranium. Similar aquatic behavior was commonly depicted for other large sauropods, such as Brachiosaurus and Apatosaurus. A 1951 study by Kenneth A. Kermack indicates that sauropods probably could not have breathed through their nostrils when the rest of the body was submerged, as the water pressure on the chest wall would be too great. Since the 1970s, general consensus has the sauropods as firmly terrestrial animals, browsing on trees, ferns, and bushes.
  Scientists have debated as to how sauropods were able to breathe with their large body sizes and long necks, which would have increased the amount of dead space. They likely had an avian respiratory system, which is more efficient than a mammalian and reptilian system. Reconstructions of the neck and thorax of Diplodocus show great pneumaticity, which could have played a role in respiration as it does in birds.
caption: Restoration of D. hallorum in environment
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