剑龙的资料（英文）
这是一篇有关恐龙的介绍， 其中stegosaurus是剑龙的介绍， 本来是想把有关剑龙的贴过来， 但我觉得多多益善， 了解多一点毕竟有好处Imagine walking through a prehistoric forest and coming face to face with a terrifying dinosaur. This could never have happened, of course. People and dinosaurs did not live on Earth at the same time. Dinosaurs died out long before people appeared. Dinosaurs lived from about 230 million years ago to about 65 million years ago.HOW DO WE KNOW ABOUT DINOSAURS?Paleontologists (scientists who study prehistoric life) learn about dinosaurs by studying fossils of their bones. These fossils are the remains of dead animals that have turned into rock.People probably found fossils of dinosaur bones thousands of years ago but did not know what the bones were. In the early 1800s, people realized that the fossil bones belonged to prehistoric animals. The first dinosaurs that paleontologists studied were named Megalosaurus and Iguanodon. The bones looked like those of reptiles, such as lizards. The flat teeth of Iguanodon showed that it was a plant eater. The pointy teeth of Megalosaurus showed that it was a meat eater.The early fossils came from England. British scientist Sir Richard Owen in 1842 named these animals dinosaurs. The word comes from two Greek words meaning “terrible” and “lizard.” Scientists now know that dinosaurs were not lizards.KINDS OF DINOSAURSPaleontologists have found fossils of hundreds of different kinds of dinosaurs that lived all over the world. Some dinosaurs were small like birds. Other dinosaurs were much bigger than an elephant.Paleontologists divide dinosaurs into two groups, or orders, by the way their hips looked. One group had hips that were like birds’ hips. They called this order Ornithischia. The other group had hips like those of lizards. They called this order Saurischia.There were three basic kinds of dinosaurs in the Saurischia order: theropods, prosauropods, and sauropods. There were five basic kinds of dinosaurs in the Ornithischia order: stegosaurs, ankylosaurs, ornithopods, pachycephalosaurs, and ceratopsians.THEROPODSAll dinosaurs were plant eaters except for theropods. Theropods were meat eaters that hunted plant-eating dinosaurs and smaller theropods. Most theropods walked on their two hind legs. One of the most famous theropods is Tyrannosaurus rex. This dinosaur was about 39 feet (12 meters) long and weighed 5 metric tons.Some theropods were called raptors. Velociraptor and other raptors had powerful claws, like the claws of an eagle. These dinosaurs probably hunted in packs.PROSAUROPODSProsauropods had spoon-shaped teeth and long, slender necks. These large, plant-eating dinosaurs stood on two legs and grazed on tall bushes and trees. One type of prosauropod, Plateosaurus, was 30 feet (9 meters) long and weighed 1.8 metric tons.SAUROPODSSauropods descended from prosauropods. Some of the best-known sauropods were Apatosaurus and Diplodocus. These dinosaurs had thick legs and feet like elephants’ feet, but with claws. They walked on four legs. At one time sauropods were the biggest dinosaurs on Earth. Some sauropods may have been more than 82 feet (25 meters) long and weighed about 90 metric tons.STEGOSAURSThese ornithischians walked on four legs and had a row of bony plates down their back. Stegosaurus, a large stegosaur, also had spikes on its tail. It used its spiked tail for fighting off meat-eating theropods. Stegosaurus was about 30 feet (9 meters) long.ANKYLOSAURSThese dinosaurs were covered with bony plates that acted as body armor to protect them against theropods. Some had a bony plate in each eyelid and large clubs on their tails. Bony rings and spines protected their necks. Ankylosaurus was about 33 feet (10 meters) long.ORNITHOPODSOrnithopods were once the most numerous plant-eating dinosaurs. There were many different kinds. Over time, ornithopods developed broad beaks. These later ornithopods are called duck-billed dinosaurs. Some ornithopods were small and ran fast. Others were huge. Iquanodon, for example, was 25 feet (7.5 meters) long.PACHYCEPHALOSAURSThese dinosaurs walked on two feet. They had thick, dome-shaped skulls. Scientists think they may have used their thick heads to butt other dinosaurs.CERATOPSIANSThese dinosaurs ware also called horned dinosaurs. One of the best-known ceratopsians was Triceratops. It had three horns on the top of its head: one horn on its snout and one horn above each eye. Triceratops could reach lengths of up to 26 feet (8 meters) and weighed more than 12 metric tons.WHAT HAPPENED TO THE DINOSAURS?There are several theories about why dinosaurs died out. Many scientists believe that there was a sudden, violent event. They think that an asteroid or comet collided with Earth. Fire from the impact burned large areas. Dust blocked sunlight from reaching the surface of Earth. Acid rain fell everywhere. Plants could not grow. There was no food for the plant-eating dinosaurs, so they died out. Dinosaurs that ate plant-eating animals also died out.Other scientists think that the environment changed. Maybe the climate grew colder and dinosaurs slowly became extinct over several million years.Many scientists think that birds descended from a small kind of dinosaur. If this is true, then dinosaurs, in a sense, are still alive in the form of modern birds.
剑龙的生活习性是什么
生活习性：剑龙与相近的恐龙皆属于草食性， 所吃的食物包括了苔藓、蕨类、木贼、苏铁、松柏与一些果实。在科罗拉多州发现的剑龙类足迹化石， 显示它们是以群体生存。
剑龙（包括剑龙下目）则的牙齿缺乏平面， 使牙齿与牙齿之间无法闭合， 它们的下颚也无法水平地运动。由于缺发咀嚼能力， 因此它们也会吞下胃石， 以帮助肠胃处理食物， 这种行为也出现在现代鸟类及鳄鱼当中。
剑龙并不像现代草食性哺乳类一样以地面上低矮的禾本科植物（草）为食， 因为这类植物是在白垩纪晚期才演化出来， 那时剑龙早已灭绝许久。
扩展资料
恐龙灭绝理论
1、德国科学家提出， 恐龙灭绝是由当时恶劣的“空间天气”造成的， 也就是说， 来自宇宙的强烈粒子流闯入地球大气并导致地球气候发生剧烈变化， 从而致使恐龙灭绝。
2、1980年， 美国科学家阿弗雷兹父子在6500万年前的地层中发现了高浓度的铱， 其含量超过正常含量几十甚至数百倍。这样浓度的铱在陨石中可以找到， 因此， 科学家们就把它与恐龙灭绝联系起来。
3、在白垩纪末期发生的造山运动使得沼泽干涸， 许多以沼泽为家的恐龙就无法再生活下去。因为气候变化， 植物也改变了， 食草性的恐龙不能适应新的食物， 而相继灭绝。
参考资料来源：百度百科-剑龙
