異特龍屬
Allosaurus

context: zh_tw: 異特龍屬於異特龍科，異特龍科是一個大型獸腳亞目的演化支。奧塞內爾・查利斯・馬什在 1878 年建立異特龍科；但在 1970 年代以前，異特龍科很少被使用，取而代之的是斑龍科，但斑龍科長期以來被當作大型獸腳類恐龍的「未歸類物種集中地」。在 1976 年麥迪遜公佈他的專題論文以前，跟異特龍相同時期被命名的腔軀龍，常被當作異特龍的同義詞，而且更常被使用。數個研究人員曾在他們的著作中使用斑龍科，而不採用異特龍科，包含：吉爾摩爾、休尼博士、羅默博士、羅德尼・史提爾、以及亞歷克・沃克。
en: Allosaurus was an allosaurid, a member of a family of large theropods within the larger group Carnosauria. The family name Allosauridae was created for this genus in 1878 by Othniel Charles Marsh, but the term was largely unused until the 1970s in favor of Megalosauridae, another family of large theropods that eventually became a wastebasket taxon. This, along with the use of Antrodemus for Allosaurus during the same period, is a point that needs to be remembered when searching for information on Allosaurus in publications that predate James Madsen's 1976 monograph. Major publications using the name "Megalosauridae" instead of "Allosauridae" include Gilmore, 1920, von Huene, 1926, Romer, 1956 and 1966, Steel, 1970, and Walker, 1964.Following the publication of Madsen's influential monograph, Allosauridae became the preferred family assignment, but it too was not strongly defined. Semi-technical works used Allosauridae for a variety of large theropods, usually those that were larger and better-known than megalosaurids. Typical theropods that were thought to be related to Allosaurus included Indosaurus, Piatnitzkysaurus, Piveteausaurus, Yangchuanosaurus, Acrocanthosaurus, Chilantaisaurus, Compsosuchus, Stokesosaurus, and Szechuanosaurus. Given modern knowledge of theropod diversity and the advent of cladistic study of evolutionary relationships, none of these theropods is now recognized as an allosaurid, although several, like Acrocanthosaurus and Yangchuanosaurus, are members of closely related families.
qas: question: zh_tw: 1878 年，獸腳亞目被進一步分類為哪科？
en: Theropods were further classified into which family in 1878?
answers: zh_tw: text: 異特龍科
en: text: Allosauridae

context: zh_tw: 在 1991 年發現的「大艾爾」標本（編號 MOR 593），是最著名的異特龍化石之一。大艾爾是個相當完整的天然狀態標本，接近 95% 完整度，身長約 8 公尺。「大艾爾」最初是由卡比・希伯（Kirby Siber）所率領的瑞士團隊發現於懷俄明州的比格霍恩縣，並由懷俄明大學地理博物館與洛磯山博物館共同挖掘出土。因為該化石相當完整，因此取了個暱稱「大艾爾」。發現大艾爾的瑞士團隊後來在同一地點發現另一異特龍化石，並取名為「大艾爾二號」，是到目前為止，儲存狀態最好的異特龍化石。
qas: question: zh_tw: 它是在什麼時候被發現的？
en: When was it discovered?
answers: zh_tw: text: 1991 年

context: zh_tw: 「大艾爾」的體型小於脆弱異特龍的平均大小，可能是個亞成年體，經估計只成長了 87%，或是另一較小的種。「大艾爾」由布倫特・布萊特豪普特（Brent Breithaupt）是在 1996 年所敘述。其中有 19 個骨頭是斷裂的，呈現出感染的跡象，這可能導致「大艾爾」的死亡。這些感染的骨頭包含五個肋骨、五節脊椎、四個腳部骨頭；數個骨頭則具有骨髓炎。右腳上的感染與傷口可能影響了大艾爾的行走，從步態的改變研判，右腳的傷口可能感染了另一隻腳。
en: In 1991  "Big Al" (MOR 693), a 95% complete, partially articulated specimen of Allosaurus was discovered. It measured about 8 meters (about 26 ft) in length. MOR 693 was excavated near Shell, Wyoming, by a joint Museum of the Rockies and University of Wyoming Geological Museum team. This skeleton was discovered by a Swiss team, led by Kirby Siber. In 1996 the same team discovered a second Allosaurus, "Big Al Two", which is the best preserved skeleton of its kind to date.The completeness, preservation, and scientific importance of this skeleton gave "Big Al" its name; the individual itself was below the average size for Allosaurus fragilis, and was a subadult estimated at only 87% grown. The specimen was described by Breithaupt in 1996. Nineteen of its bones were broken or showed signs of infection, which may have contributed to "Big Al's" death. Pathologic bones included five ribs, five vertebrae, and four bones of the feet; several damaged bones showed osteomyelitis, a bone infection. A particular problem for the living animal was infection and trauma to the right foot that probably affected movement and may have also predisposed the other foot to injury because of a change in gait. Al had an infection on the first phalanx on the third toe that was afflicted by an involucrum. The infection was long lived, perhaps up to 6 months. Big Al Two is also known to have multiple injuries.
qas: question: zh_tw: 可能是什麼並導致了異特龍「大艾爾」的死亡？
en: The allosaurus may have died due to what ailment?
answers: zh_tw: text: 感染
en: text: infection

question: zh_tw: 它是在什麼時候被發現的？
answers: en: text: 1991

context: zh_tw: 異特龍與其他侏儸紀獸腳類恐龍共同生存在莫里遜組與葡萄牙，包含：角鼻龍、體型較大的蠻龍，這點很不尋常。根據生理結構與化石位置，牠們三者似乎擁有不同的生態位。角鼻龍與蠻龍可能活躍於河道附近，牠們的身體較瘦、較低矮，可使牠們躲藏在森林或矮樹叢中；異特龍的腿部較長、速度較快，但牠們在森林或矮樹叢中較不靈活，因此可能活躍於乾燥的泛濫平原中。目前對於角鼻龍的研究比蠻龍還深入。角鼻龍與異特龍的差別在於，牠們的頭顱骨較高、較狹窄，而牙齒較大、較寬廣。在一個異特龍的恥骨末端發現了另一個獸腳類恐龍的齒痕，可能是由角鼻龍或蠻龍所留下的，這顯示異特龍可能也是其他獸腳類恐龍的食物來源選擇之一。恥骨是位於腹部下緣，夾處兩腿之間，處於身體最龐大的地方之一。顯示這隻異特龍是在死後，屍體被其他恐龍所吞食。
en: The Morrison Formation has been a rich fossil hunting ground. The flora of the period has been revealed by fossils of green algae, fungi, mosses, horsetails, ferns, cycads, ginkgoes, and several families of conifers. Animal fossils discovered include bivalves, snails, ray-finned fishes, frogs, salamanders, turtles, sphenodonts, lizards, terrestrial and aquatic crocodylomorphans, several species of pterosaur, numerous dinosaur species, and early mammals such as docodonts, multituberculates, symmetrodonts, and triconodonts. Dinosaurs known from the Morrison include the theropods Ceratosaurus, Ornitholestes, Tanycolagreus, and Torvosaurus, the sauropods Haplocanthosaurus, Camarasaurus, Cathetosaurus, Brachiosaurus, Suuwassea, Apatosaurus, Brontosaurus, Barosaurus, Diplodocus, Supersaurus, and Amphicoelias, and the ornithischians Camptosaurus, Dryosaurus, and Stegosaurus. Allosaurus is commonly found at the same sites as Apatosaurus, Camarasaurus, Diplodocus, and Stegosaurus. The Late Jurassic formations of Portugal where Allosaurus is present are interpreted as having been similar to the Morrison but with a stronger marine influence. Many of the dinosaurs of the Morrison Formation are the same genera as those seen in Portuguese rocks (mainly Allosaurus, Ceratosaurus, Torvosaurus, and Stegosaurus), or have a close counterpart (Brachiosaurus and Lusotitan, Camptosaurus and Draconyx).Allosaurus coexisted with fellow large theropods Ceratosaurus and Torvosaurus in both the United States and Portugal. The three appear to have had different ecological niches, based on anatomy and the location of fossils. Ceratosaurs and torvosaurs may have preferred to be active around waterways, and had lower, thinner bodies that would have given them an advantage in forest and underbrush terrains, whereas allosaurs were more compact, with longer legs, faster but less maneuverable, and seem to have preferred dry floodplains. Ceratosaurus, better known than Torvosaurus, differed noticeably from Allosaurus in functional anatomy by having a taller, narrower skull with large, broad teeth. Allosaurus was itself a potential food item to other carnivores, as illustrated by an Allosaurus pubic foot marked by the teeth of another theropod, probably Ceratosaurus or Torvosaurus. The location of the bone in the body (along the bottom margin of the torso and partially shielded by the legs), and the fact that it was among the most massive in the skeleton, indicates that the Allosaurus was being scavenged.
qas: question: zh_tw: 哪種恐龍的腿最長
en: Which dinosaurs had the longest legs
answers: zh_tw: text: 異特龍的腿部較長、速度較快，但牠們在森林或矮樹叢中較不靈活，因此可能活躍於乾燥的泛濫平原中。
en: text: allosaurs

context: zh_tw: 異特龍被認為是種主動攻擊的大型掠食動物。根據蜥腳類恐龍骨頭上的異特龍齒痕，以及與蜥腳類化石一起發現的零散異特龍牙齒來判斷，異特龍可能以蜥腳類恐龍為獵食物件，或是搜尋牠們的屍體為食。另外有明確證據顯示異特龍曾經攻擊過劍龍，例如一個異特龍的尾椎上有個部分痊癒的傷口，這個被刺穿傷口的形狀符合劍龍的尾刺；另外，在一個劍龍的頸部骨板上有個 U 形的傷口，與異特龍的嘴部形狀符合。在 1988 年，葛瑞格利・保羅（Gregory Paul）提出異特龍不可能以蜥腳類恐龍為食，除非採取群體方式獵食；因為異特龍的頭部大小屬中型、牙齒相對較小，體型也無法與同時代的大型蜥腳類恐龍相比。另一個可能則是異特龍以幼年蜥腳類恐龍為獵食物件，而不獵食完全成長的蜥腳類恐龍。1990 年代與 2000 年代的研究可能解答了這個問題。羅伯特・巴克（Robert T. Bakker）將異特龍與一些生存於新生代肉食性哺乳類相比，發現類似的適應演化，例如：頜部肌肉的縮小、頸部肌肉的增大、以及將頜部左右撐開的能力。雖然異特龍的牙齒並非如這些哺乳類呈刀刃狀，巴克提出了另一種異特龍的攻擊方式：上頜的短牙齒會形成類似鋸子的小型鋸齒表面，可切入獵物肉體。這種型態的頜部可使異特龍採取撕咬方式攻擊大型獵物，消耗獵物的體力。
en: Paleontologists accept Allosaurus as an active predator of large animals. There is dramatic evidence for allosaur attacks on Stegosaurus, including an Allosaurus tail vertebra with a partially healed puncture wound that fits a Stegosaurus tail spike, and a Stegosaurus neck plate with a U-shaped wound that correlates well with an Allosaurus snout. Sauropods seem to be likely candidates as both live prey and as objects of scavenging, based on the presence of scrapings on sauropod bones fitting allosaur teeth well and the presence of shed allosaur teeth with sauropod bones. However, as Gregory Paul noted in 1988, Allosaurus was probably not a predator of fully grown sauropods, unless it hunted in packs, as it had a modestly sized skull and relatively small teeth, and was greatly outweighed by contemporaneous sauropods. Another possibility is that it preferred to hunt juveniles instead of fully grown adults. Research in the 1990s and first decade of the 21st century may have found other solutions to this question. Robert T. Bakker, comparing Allosaurus to Cenozoic sabre-toothed carnivorous mammals, found similar adaptations, such as a reduction of jaw muscles and increase in neck muscles, and the ability to open the jaws extremely wide. Although Allosaurus did not have sabre teeth, Bakker suggested another mode of attack that would have used such neck and jaw adaptations: the short teeth in effect became small serrations on a saw-like cutting edge running the length of the upper jaw, which would have been driven into prey. This type of jaw would permit slashing attacks against much larger prey, with the goal of weakening the victim.
qas: question: zh_tw: 誰將異特龍與新生代動物相比？
en: Who comapred the Allosaurus to the Cenozoic?
answers: zh_tw: text: 羅伯特・巴克（Robert T. Bakker）
en: text: Robert T. Bakker

context: zh_tw: 一個針對異特龍腦部的電腦斷層掃描，發現牠們的腦部與鱷魚有較多的共同點，而與現代鳥類腦部的共同點較少。前庭器官的結構顯示牠們的頭部保持在幾乎水平的位置，而非朝上或朝下。內耳的結構類似鱷魚，所以異特龍可能容易聽到低頻的聲音，但難以聽到細微的聲音。異特龍的嗅球大，可能適合感覺氣味，但辨別氣味的區域相當小。
en: The brain of Allosaurus, as interpreted from spiral CT scanning of an endocast, was more consistent with crocodilian brains than those of the other living archosaurs, birds. The structure of the vestibular apparatus indicates that the skull was held nearly horizontal, as opposed to strongly tipped up or down. The structure of the inner ear was like that of a crocodilian, and so Allosaurus probably could have heard lower frequencies best, and would have had trouble with subtle sounds. The olfactory bulbs were large and seem to have been well suited for detecting odors, although the area for evaluating smells was relatively small.
qas: question: zh_tw: 異特龍的前庭器官證明了什麼？
en: What did the vestibular apparatus prove about Allosaurus?
answers: zh_tw: text: 頭部保持在幾乎水平的位置
en: text: the skull was held nearly horizontal