dinosaur
(English: adinosaur) is a group of diversified dominant vertebrates in Mesozoic, which dominated the global terrestrial ecosystem for more than 65.438+0.6 billion years. Dinosaurs first appeared in the Triassic period 230 million years ago and died out in the late Cretaceous period about 65 million years ago. In 2005, Japanese archaeologist Guan Ling discovered new evidence that dinosaurs might hatch in eggs.
The archaeopteryx fossils found in 1862 are very similar to the megagnathus fossils, but the difference is that the archaeopteryx fossils have feather marks, which indicates that dinosaurs and birds may be close relatives. Since 1970, many studies have pointed out that modern birds are probably the direct descendants of theropod dinosaurs. Most scientists regard birds as the only dinosaurs that have survived and developed to this day, while a few scientists even think that they should be classified into the same category. Crocodiles are modern close relatives of another kind of dinosaurs, but their relationship is farther than that between dinosaurs and birds. Dinosaurs, birds and crocodiles all belong to the evolutionary branch of reptiles, which first appeared in the late Permian and became the dominant fauna in the middle Triassic.
In the first half of the 20th century, scientists and mass media regarded dinosaurs as slow-moving and lazy cold-blooded animals. However, the dinosaur revival that began in 1970 shows that dinosaurs may be active warm-blooded animals and may have social behaviors. Many recent evidences of the relationship between dinosaurs and birds support the hypothesis that dinosaurs were warm-blooded animals.
Classification of dinosaurs The biggest difference between dinosaurs and other reptiles lies in their standing posture and way of marching. Dinosaurs are completely upright, with their limbs directly under their bodies. This structure has advantages over other kinds of reptiles (such as crocodiles, whose limbs extend outward) when walking and running. According to the different structural characteristics of dinosaur belts, they can be divided into two categories: sauropods and ornithosaurs.
The difference between them lies in the band structure: the band of sauropods is three shots from the side, the pubic bone extends forward under the intestinal bone, and the sciatic bone extends backward, similar to lizards; The waistband of ornithischia expands greatly in the front and back of the intestinal bone, and there is a large pubic protrusion on the front side of the pubic bone, which extends below the intestinal bone, and the back side extends parallel to the ischium to the front and bottom of the intestinal bone. So from the side, the pelvis is radiant. Whether sauropods or birds, their belts leave a small hole between the intestine, ischium and pubis, which other reptiles do not have. It is this hole that shows that compared with all other reptiles of all orders, the two orders called dinosaurs are the closest.
Sauropods are divided into sauropods and theropods.
Sauropods are divided into protosauropods and sauropods. Protosauropods mainly lived in the Late Triassic to the Early Jurassic, and were omnivorous-vegetarian medium-sized dinosaurs. Sauropods mainly live in Jurassic and Cretaceous. Most of them were giant vegetarian dinosaurs. Small head, long neck, long tail and small teeth in spoon shape. The famous representative of sauropod is Mamen Xilong, which was produced in China, Sichuan and Gansu in the Late Jurassic. The neck length of 19 cervical vertebra is about half of the body length.
Theropod dinosaurs lived from the Late Triassic to the Cretaceous. They are all carnivorous dragons, walking on two feet, with sharp claws at their toes and teeth as sharp as daggers or knives in their mouths. Tyrannosaurus rex is a famous representative.
The suborder ornithopoda can be divided into five categories: ornithopoda, stegosaurus, Ankylosaurus, Ceratosaurus and pachycephala.
Ornithopoda is a group with the most fossils in ornithopoda and even the whole dinosaur category. They walk on two or four feet. The mandible has a single anterior tooth bone, and the teeth only grow on the cheeks. The crowns of the maxillary teeth bend inward and the crowns of the mandibular teeth bend outward. They lived from the late Triassic to the Cretaceous, and they were all vegetarian dinosaurs.
Stegosaurus was a quadruped with an upright bone plate on its back and two pairs of bone spurs on its tail. It mainly lived from Jurassic to early Cretaceous, and it was the first extinct dinosaur.
Ankylosaurus was short and strong, covered with a bone deck, and ate plants, mainly living in Cretaceous.
Ceratosaurus is a four-legged vegetarian dinosaur. The back of the skull expanded into a cervical shield, most of which lived in the late Cretaceous. The parrot-billed dragon found in northern China belongs to the ancestor type of Ceratosaurus.
The main characteristics of pachycephalosaurus are that the skull is swollen and thick, the hole is closed, and the pubic bone in the pelvis is rejected by the ischium and does not participate in the formation of the band. It mainly lived in Cretaceous.
Edited on 202 1-02-22
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A short article about dinosaurs (100 words)
Dinosaurs are Mesozoic reptiles, which appeared 245 million years ago and flourished 65 million years ago. Or both dinosaurs and plesiosaurs and pterosaurs. The sudden disappearance of dinosaurs at the end of Cretaceous 6.5 million years ago became a mystery in the evolutionary history of life on earth. This mystery has not been solved so far. In the past, all living things on the earth were recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata, and a large number of bones or various shapes can be seen in these strata. Zigong Weibo Dinosaur Production and Exhibition Co., Ltd. is a wholly-owned subsidiary of Zigong Weibo Culture and Art Co., Ltd., which is a professional enterprise engaged in simulation, bionics, dinosaurs, animals, light shows, production, display and sales. Business simulation dinosaurs, glass fiber reinforced plastic model dinosaurs, electric model dinosaurs, dinosaur fossils, mechanical dinosaurs, high-tech aliens, alien beasts, prehistoric animals, electric lanterns, lanterns, floats, floats.
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Introduce a dinosaur composition, limited to 150 to 200 words.
Tyrannosaurus rex, also known as Tyrannosaurus rex, is 13 meters long and weighs about 14 kilograms. The fossil division is in North America, the United States and western Canada! Tyrannosaurus rex can be said to be the fiercest animal among carnivorous dinosaurs, and Tyrannosaurus rex is the second largest carnivorous dinosaur in the world. But the body length is the fifth. Tyrannosaurus rex's main food was triceratops, because some scientists found that a triceratops had teeth marks on its bones. And it was bitten by Tyrannosaurus rex's teeth. Now people agree that the food of Tyrannosaurus Rex is Triceratops. Tyrannosaurus rex has a big head, small forelimbs, big and powerful hind feet, and its speed is 18? 19 km. I think Tyrannosaurus rex must be bloody when eating!
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Dinosaur information 150 words
Dinosaur [1] (scientific name: dinosaur) is a terrestrial vertebrate with diversified advantages in Mesozoic, which once dominated the global terrestrial ecosystem for more than10.6 billion years. Dinosaurs first appeared in the Triassic period 230 million years ago and died out in the late Cretaceous period about 65 million years ago. 186 1 The archaeopteryx fossils found are very similar to those of Megagnathus, but the difference is that the archaeopteryx fossils have traces of feathers, which indicates that dinosaurs and birds may be close relatives. Since 1970, many studies have pointed out that modern birds are probably the direct descendants of theropod dinosaurs. Most scientists regard birds as the only dinosaurs that have survived and developed so far, and a few even advocate putting them in the same category. Dinosaurs, birds and crocodiles all belong to the main evolutionary branches of reptiles, which first appeared in the late Permian and became the dominant land animals in the middle Triassic.
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The information about dinosaurs is within 100 words.
Dinosaur (English name: dinosaur) is a reptile that appeared in Mesozoic (Triassic, Jurassic and Cretaceous). Its vigorous limbs, long tail and huge body are the portrayal of most dinosaurs. They mainly inhabit woodland or open areas in lakeshore plains (or coastal plains). 184 1 year, when British scientist richard owen studied several lizard-like bone fossils, he thought they were left by some prehistoric animals and named them dinosaurs, which means "scary lizards". The sudden disappearance of dinosaurs at the end of Cretaceous 65 million years ago became a mystery in the evolutionary history of life on earth. This mystery has not been solved so far. In the past, all living things on the earth were recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata. There are many kinds of dinosaurs, and their shapes and habits are very different. The largest fragile double-chambered dragon may be more than 50 meters, while the smallest hummingbird may be less than 10 cm. As far as eating habits are concerned, there are docile herbivores and fierce carnivores, as well as omnivorous dinosaurs who are both vegetarian and vegetarian. Extended data:
The main morphological characteristics of dinosaurs: 1. Skeletal characteristics The dinosaur bones have some evolutionary adaptations, which can be distinguished from the original dragon ancestors. In the late dinosaur period, these characteristics experienced more evolutionary changes. Most dinosaurs still have some * * * characteristics, but they are not classified as dinosaurs because they appear in other main dragons or early dinosaurs. Dinosaurs walked upright, similar to most modern mammals, while most other reptiles walked with their limbs extended to both sides. 2, the body characteristics of dinosaurs as a whole is very large. According to dinosaur standards, lizard's foot is one of the behemoths. In the long dinosaur era, even the smallest sauropods were larger than other animals in their habitats, while the largest sauropods were several grades larger than any animals that appeared on the surface. 3. The main difference between dinosaurs and other reptiles lies in their standing posture and marching way. Dinosaurs are completely upright, with their limbs directly under their bodies. This structure has more advantages than other reptiles (such as crocodiles, whose limbs extend outward) when walking and running. According to the different structural characteristics of dinosaur belts, they can be divided into two categories: sauropods and ornithosaurs. The main difference between them lies in their belt structure. Baidu encyclopedia-dinosaur
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How to write an introduction about dinosaurs in 150 words? Urgent! Urgent! Urgent! Urgent! Urgent! This is an emergency!
Dinosaur, do you know who was the overlord of Jurassic? Let me tell you, that's Tyrannosaurus rex. The following is its information: Tyrannosaurusrex, also known as Tyrannosaurus rex, is the only effective species in the current model species, or Tyrannosaurus rex. It is a large carnivorous Tyrannosaurus rex, about 13 meters long and weighing about 7 metric tons. It lived in the last 3 million years of the Maastricht stage at the end of Cretaceous, about 68.5 million to 65.5 million years ago, that is, the first Cretaceous. Fossils are distributed in North America, the United States and western Canada, and the distribution range is wider than other Tyrannosaurus rex. It's my favorite dinosaur. Below is the hadrosaur, which lived in the late Cretaceous 65438+ billion years ago and was the peak of dinosaur development, so it was abundant, accounting for about 75% of herbivorous dinosaurs. They are a large bird-buttock dinosaur. At present (2008), it is found that the maximum length exceeds 2 1 m. Due to the extension and lateral expansion of the maxillary and odontoid bones, the snout of the hadrosaurs formed a wide duckbill-shaped snout, hence the name. I think it's cute. Omnivorous dinosaurs, I prefer earthquake dragons. Earthquake dragon means "lizard of earthquake". It was first discovered in 1979, New Mexico, USA, in the late Jurassic. It has been found that the body has a tail; Back; Hips and hind limbs. At first glance, it looks like Liang Long, but the earthquake dragon has a longer tail and a thick pelvis. According to preliminary estimates, its length is at least 35 meters, even more than 40 meters. But now it has shrunk to 32 meters long and weighs 22-27 tons. Zhenlong has a long neck, a small head and a slender tail. The nose grows on the top of the head. Its head and mouth are small, with flat round teeth in front and no teeth in the back. The front legs of zhenlong are shorter than the rear legs. Each foot has five toes, one of which has claws. The earthquake dragon walks on four feet and walks very slowly. They live in groups. Zhenlong is a herbivore. When eating, Zhenlong swallowed all the leaves without chewing. Seismosaurus is one of the largest dinosaurs, but some scientists believe that the dinosaur fossils found belong to an oversized Liang Long. It was once recognized that the longest dinosaur was zhenlong. The next one is a long-necked dragon living in the sea. Tanystropheus is a reptile that lived in the Middle Triassic, and its length is about 6 meters (20 feet). The main feature is an extremely long neck, which is as long as 3 meters (10 feet), which is longer than the body and tail combined. Although the neck is so long, it has only 12 vertebrae, and each vertebra is quite long. Fossils of long-necked dragons have been found in Europe and the Middle East. Many complete young specimens of sauropod were found in the Besano Formation in Italy, and the geological age was Latin period of Middle Triassic, about 232 million years ago [1]. The generic name of the long-necked dragon means "long spine", and the introduction ends here. Goodbye.
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Introduction of dinosaurs
Introduction to dinosaurs dinosaurs originated from microorganisms that lived in the ocean billions of years ago. Gradually, microorganisms evolved into fish. Because there are more and more creatures in the ocean, fish have evolved into amphibians that walk on land and then into reptiles. Dinosaurs are called the king of the land. They lived in the Mesozoic from about 225 million years ago to 65 million years ago, which lasted about 65.438+60 billion years. During this long period, the plants on the land have also changed with the changes of the times. The Triassic period of dinosaur period (about 248 million to 280 million years ago) was the first period of Mesozoic. At that time, all the land formed a supercontinent called Pangea, which was called Laoyasia in the north and Gondwana in the south. _ _ _ At that time, the climate around was limited to warm or hot. There is no ice cover in the polar regions. Deserts spread in inland areas, and flowering plants have not yet evolved. Jurassic (about 265,438+1100 million years ago) is the second period of Mesozoic. Conifers and ginkgo trees flourish in Asia. Pangea continued to separate. Cretaceous (about 654,38+1.400-65 million years ago) is the third stage of Mesozoic. However, at the end of this era, they were all extinct. Pangu, which began to split in Triassic, quickly formed the Atlantic Ocean in Cretaceous. From 65 million years ago to the present, dinosaurs in the dinosaur era can be roughly divided into two orders: sauropods and ornithopods. Sauropods: Sauropods have a triangle similar to lizards. The original type is hind-footed walking, and progress represents quadruped walking. There are carnivorous dinosaurs and vegetarian dinosaurs. According to "limb bone structure" and "lifestyle", sauropods are divided into two suborders: theropod and sauropod. Bird-footed: The belt is radiant, similar to birds. Except ornopods, all the others are quadrupeds, most of them are vegetarian dinosaurs, and a few are omnivores. Ornopods is * * *. Ceratosaurus and pachycephalosaurus. There are many possibilities for the extinction of dinosaurs. The following theories are more true: 1) Planetary impact theory: Iridium is rarely found on the earth, but it is found in Cretaceous sediments, which makes people guess that it is evidence left by planetary impact. It is estimated that the dense dust on the surface caused by the impact blocked the sunlight at that time, resulting in a large number of plant deaths. The earth has a cold climate, and vegetarian dinosaurs died because of the food chain. Carnivorous dinosaurs eventually followed suit. At that time, even if there were a few small dinosaurs, they would not be spared soon. This is the most likely reason for the extinction of dinosaurs. 2) The appearance of mammals: At the end of Cretaceous, vegetarian dinosaurs were eaten up by carnivorous dinosaurs and had to kill each other. At the same time, small mammals take risks because of excessive famine and steal dinosaur eggs for a living. The descendants of dinosaurs were seriously threatened, and some even speculated that this happened in the dinosaur race at that time. 3) Volcanic eruption theory: Frequent volcanic activities in the late Cretaceous brought about chronic disasters, and a large number of volcanic ash erupted, which often drowned groups of ancient creatures. (The formation of Confucius birds may be one of them), the atmosphere gradually darkened, plants withered, and animals hunted each other and died together. Dinosaurs extinct the biggest dinosaur: "Zhenlong", walking like an earthquake. Therefore, it was named .65438+August 0986. It was unearthed in central New Mexico, with a body length of about 50 meters, making it the largest and longest dinosaur record in the world. ● The hardest dinosaur: "Pachysaurus", about 8 meters long, late Cretaceous. ● The largest number of dinosaurs: "Cimulong", late Cretaceous, with a total length of about 9 meters. ● The smallest dinosaur: "Only chickens are as big as chickens, but they are very fast. ● The fastest dinosaur: Deinonychus, in the middle Cretaceous, with a total length of about 3 meters, hunted in groups. The most brutal dinosaur: Tyrannosaurus Rex, about 14 meters tall and weighing about 10 metric ton, was the last carnivorous dinosaur in the American continent in the late Cretaceous. It is said that they will eat the carrion of dead dinosaurs. ● Dinosaur with the largest number of teeth: "Duckbilled Dragon", 8 ~ 10 m in the late Cretaceous, with more than 2,000 teeth. ● Dinosaur with the largest number of decorations on its back: "Stegosaurus", about 8 meters in the late Jurassic, with a shield as high as 80 cm on its back. ● The dinosaur with the best eyesight: "Like a bird dragon" has eyes as big as 10 cm. The largest dinosaur: Triceratops, late Cretaceous, about 8 meters long, but the head was about 2.6 meters. Dinosaur Fossils The corpse of a dinosaur became a fossil hundreds of millions of years later, and it was discovered again due to geological erosion. These fossils have been studied, repaired and shaped by experts, and finally the image of this dinosaur is shown to everyone. Coupled with rich imagination and artist's expressive force, a dinosaur skeleton can be restored. The restored bones and skin can draw a restored picture of dinosaurs. The recovered dinosaur must conform to the law of biological life, otherwise it will go wrong. There is a small place called Lewis in Sussex in the south of England. 180 years ago, there was a village doctor named mantel. This Mr mantel is full of curiosity about nature, especially like collecting and studying fossils. After practicing medicine and treating diseases, he often climbed mountains and waded with his wife to find and collect fossils, and his footprints were all over the bare ravines and gullies of rocks. As time went on, Mrs Mantell became a "friend of nature" and an expert in fossil collection. One day in March 2008 +0822. It was cold, but Mr mantel went out to see the patient as usual. Mrs mantel is waiting for her husband to come back at home, and she is always worried that he will catch cold. Later, Mrs Mantell couldn't sit still, so she took her husband's clothes and went out to see him in the direction of his house calls. She walked on a road under construction, and the newly dug steep walls on both sides of the road exposed layers of rocks. She habitually walked and observed the newly exposed rock formations on both sides. Suddenly, it turned into some strange animal tooth fossils. These fossil teeth are so big that Mrs Mantell has never seen such big teeth. The excitement of discovery made Mrs mantel forget to send clothes to her husband. She carefully took these fossils out of the rocks and took them home. One day, two years after the earliest discovery of dinosaurs, he came across a naturalist who worked in the Royal College Museum in London. This man is studying a modern lizard-iguana, which lives in Central America. So Mr Mantel took those fossils to the Royal College Museum in London, and compared them with the teeth of iguanas collected by naturalists, and found that they were very similar. Mr mantel, who was overjoyed, concluded that these fossils belonged to an extinct ancient reptile similar to an iguana. With the discovery of more and more fossil materials, people have a deeper understanding of these ancient animals. We know that the so-called "iguana's teeth" are actually a member of a wide variety of dinosaur families. It does belong to reptiles such as iguanas, but its genetic relationship with real iguanas is farther than that with other dinosaurs! However, according to the biological naming rules, the Latin word of the earliest scientifically recorded dinosaur name has not changed, and it still means "teeth of an iguana". However, its Chinese name has been translated into Iguanodon. So please remember that Iguanodon is the earliest recorded dinosaur in the history of science. At the same time, don't forget the name Mantel and the origin of his wife who loves nature. The name "dinosaur" is actually. It must be a long history for humans to discover dinosaur fossils. Before the Mantels discovered Iguanodon, Europeans knew that there were many grotesque huge bone fossils buried underground. But at that time, people didn't know their exact ownership, so they were always mistaken for "the remains of giants." As for China, as early as 2000 years ago, we began to collect large ancient animal fossils unearthed underground for medicine, and called them "keels". Who can be sure? Is the name "keel" not related to the discovery of dinosaur fossils? However, it was not until Mantels discovered Iguanodon and compared it with iguana that the scientific community initially determined that Iguanodon was an extinct reptile similar to lizard. Therefore, the names of new types of dinosaurs and other ancient reptiles discovered later are all related to lizards, such as "lizards like whales" and "lizards in the forest". Because these ancient animal fossils that initially attracted people's attention are often huge and grotesque, which is really frightening. With the continuous discovery and excavation of these horrible ancient animal fossils similar to lizards, their species are increasing, and many naturalists have begun to realize that they should be self-contained in animal taxonomy. By 1842, the British paleontologist Sir Owen created a name for them in Latin, which consisted of two roots. The former root means "scary" and the latter root means "lizard". Since then, "scary lizard" has become the general name of this large class of reptiles. They are related to each other, but they show various forms. We in China have both imagination and generalization. Translate this Latin name into "dinosaur". Now we know that there are indeed many horrible behemoths in the dinosaur family, but there are also some small and lovely "little things". If you go to the China Museum of Ancient Zoology, which is not far to the west of Beijing Zoo, their sizes range from parrot-billed dragon with a length of less than 1 m to Mamen Xilong with a length of 22 meters. Dinosaurs of different shapes will definitely give you a more comprehensive understanding of the dinosaur world. Now we also know that dinosaurs were not lizards at all. Although they all belong to reptiles, the genetic relationship between dinosaurs and lizards is quite different in a large family of reptiles. So far, the largest dinosaur we have found is Zhenlong, which is 39 to 52 meters long! The height can reach 18 meters! ! The weight reaches 130 tons! ! ! That is to say, if two or three dragons are connected end to end, they can row from one door of the football field to another. If such a heavy monster walks on the leaf, the earth will tremble every time its giant feet step on the ground. Just like an earthquake, this is the meaning of the name "Jilong". Zhenlong lived in the Late Jurassic from about1620,000 years ago to1360,000 years ago. In animal taxonomy, it belongs to sauropod, sauropod and Diptera. In addition to Zhenlong, giant sauropods (commonly known as sauropods Lei Long (length 2 1 m, weight 25 tons), Long Chao (length 42 m, shoulder height 5. 19 m, hip height 4.58 m), Mamenxilong (length 22 m) and Brachiosaurus (length 25 m) living on the earth at that time. These giant dinosaurs are all. Their tall bodies and long necks enable them to eat leaves from tall trees. Such a huge body certainly needs a lot of food, but these dinosaurs have small heads and small mouths. How can they satisfy such a large appetite? Maybe they just keep eating. Scientists speculate that Mamen Xilong will spend 23 hours eating every day! I am afraid it is also the highest in the world. Think about how many leaves a Mamenxilong will eat in 23 hours. There are thousands of other Mamenxi dragons, and many other giant sauropods. It seems that at that time, the earth must be full of dense plants and forests, and the natural environment was very superior, which made so many giants live leisurely on the earth. Now, we can never see such a huge one on land. Only blue whales living in the ocean can compare with it. Female blue whales can grow to more than 30 meters and weigh 200 tons. The longest dinosaur footprint in the world In the 1990s, a paleontological expedition led by Professor Martin Lockley, a dinosaur footprint expert from the University of Colorado in Denver, USA, was on a mudflat on the border between Turkmenistan and Uzbekistan. So far, the longest dinosaur footprint fossil in the world has been discovered. Among them, five footprints are longer than the world's longest dinosaur footprints found in Portugal in the past, with the lengths of147m,184m,195m and 226m respectively. 262 meters and 3 1 1 meter. _ These footprints were left by more than 20 Megalodon sharks. Megalodon sharks are carnivorous dinosaurs similar to Tyrannosaurus Rex, but they lived in the late Jurassic period1550,000 years ago, before Tyrannosaurus Rex appeared. _ The newly discovered footprints are very similar to those found in North America and Europe. It shows that Megalodon was widely distributed in the late Jurassic. _ The size of each footprint is similar to that of a Tyrannosaurus Rex more than 60 centimeters long. Footprints also show that its heel is relatively long. The stride of footprints shows that these Megalodon sharks are only slightly smaller than Tyrannosaurus Rex, about 12.2 meters long. Like all carnivorous dinosaurs, Megalodon's footprint shows that one foot's footprint does not fall in front of the other, but there is a gap of more than 90 cm between the left and right footprints. Scientists speculate that Megalodon is likely to stumble like a duck. Paleontologists in the early dinosaur pedigree thought dinosaurs were self-contained reptiles, so they classified them as "dinosaurs". Later, when scientists learned more about these animals, they found that they actually included two different reptiles, namely sauropods (commonly called sauropods) and ornithopods (commonly called ornithopods). The difference between them lies in the structure of waist and hip (anatomically called belt): the belt of sauropods is tridentate from the side, with the pubic bone extending forward under the intestinal bone and the ischium extending backward, similar to lizards; The waistband of the bird's hip greatly expands the intestinal bone, and the pubic protrusion is large, protruding below the intestinal bone. Therefore, the pelvis is quadrangular when viewed from the side, and the four protruding parts (four branches) are composed of the front and back of the intestine, the anterior pubic branch (also called protrusion or anterior pubic branch) and the ischium, pubic body and posterior pubic branch (also called kyphosis) which are tightly squeezed together. There is a hole between the ischium and pubic bone. This kind of hole is not found in other reptiles with various purposes. Scientists speculate that it is this hole that shows that these two orders, called dinosaurs, have the closest genetic relationship compared with all other reptiles of various purposes. These two dinosaurs originated from the Late Triassic Dentata. Whether sauropods or birds, their belts remain between the intestine, ischium and pubis.