catalogue
Briefly introduce the time of extinction
The origin of the name
Relationship with reptiles, mammals and birds now
Diversified development
Biological habit
Dinosaur migration
Dinosaur habit
Dinosaur era
Fossil excavation
Exact attribution
Dinosaur category
Specific species
The latest theory of dinosaur extinction
Meteorite collision
Formation of mountains
climate change
Ocean ebb tide
Volcanic eruption
warm-blooded animal
Mishandle with each other, incompatible.
The evolution of breastfeeding
Species theory
Frustration theory
Catastrophe theory
Theory of change
China theory
Comprehensive cause theory
The most brief introduction to the extinction time of dinosaurs
The origin of the name
Relationship with reptiles, mammals and birds now
Diversified development
Biological habit
Dinosaur migration
Dinosaur habit
Dinosaur era
Fossil excavation
Exact attribution
Dinosaur category
Specific species
The latest theory of dinosaur extinction
Meteorite collision
Formation of mountains
climate change
Ocean ebb tide
Volcanic eruption
warm-blooded animal
Mishandle with each other, incompatible.
The evolution of breastfeeding
Species theory
Frustration theory
Catastrophe theory
Theory of change
China theory
Comprehensive cause theory
Dinosaurs are the best
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Dinosaurs (40 pictures) Some dinosaurs have been extinct, while others have continued to breed to this day (such as turtles, lizards, crocodiles and snakes). ); Some dinosaurs evolved into birds and mammals today in different directions. Dinosaur (English: dinosaur) full name: scary lizard, an animal that lived about 235 million to 65 million years ago, is a group of diversified dominant vertebrates in Mesozoic, most of which belong to terrestrial, some of which live in the ocean (such as ichthyosaurs), and some reptiles that occupy the sky and can fly (such as pterosaurs), which dominate the global land, sea and air ecosystems for more than 65.438+600 million.
Extinction time
Dinosaurs first appeared in the late Triassic about 235 million years ago and died in the late Cretaceous extinction about 65 million years ago.
The origin of the name
In fact, human beings have a long history of discovering dinosaur fossils. Long before the discovery of Iguanodon, Europeans knew that there were many grotesque huge bone fossils buried underground. It was not until paleontologist Mantel discovered Iguanodon and compared it with iguana that the scientific community initially determined that it was a group of extinct lizard-like reptiles. dinosaur
1842, British paleontologist Charles Owen coined the word "dinosaur". English dinosaurs came from the Greek deinos (scary) Saurosc (lizard or reptile). For Owen at that time, this "scary lizard" or "scary reptile" refers to an extinct large reptile (actually it is not). In fact, not many dinosaurs were found at that time. Since the discovery of dinosaur fossils in Antarctica in 1989, dinosaur remains have been found in seven continents all over the world. At present, there are at least 650 to 800 genera of dinosaurs described in the world (species and genera in paleontology are not completely different from the classification of modern animals). Later, scholars in China, Japan and other countries translated it into a dinosaur, because there have been legends about dragons in these countries, which think that dragons are the length of scale worms and snakes are another name for dragons.
Relationship with reptiles, mammals and birds now
1862 The archaeopteryx fossils found are very similar to those of Megalodocus, but the difference is that the archaeopteryx fossils have obvious feathers (Megalodocus also has feathers, but it is very primitive). In fact, quite a few carnivorous dinosaurs have primitive feathers, which indicates that dinosaurs and birds may be close relatives. Since 1970, many research reports have pointed out that modern birds are probably the direct descendants of theropod dinosaurs. 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 branches of primitive dragons, which first appeared in the late Permian and became the dominant fauna in the middle Triassic. Mammals originated from reptiles, whose predecessor was "mammal-like reptiles" and early was "reptile-like mammals". Most of Mesozoic reptiles died out at the end of Mesozoic. Some reptiles (such as turtles, snakes, crocodiles, etc. ) has adapted to the ever-changing environment and has been preserved; Some of them evolved into birds and mammals today along different evolutionary directions.
Diversified development
dinosaur
From the early Jurassic to the late Cretaceous, the dinosaur family adapted to the environment and developed rapidly, which led to the diversification of dinosaurs and the increase of dinosaur population, which gave dinosaurs an advantage and enabled them to dominate the earth's ecosystem. There are many kinds of dinosaurs, and their shapes and habits are quite different. Among them, the big one can be as big as dozens of elephants combined; Small, but almost like a chicken. As far as food habits are concerned, dinosaurs have mild vegetarians (dinosaurs that ate plants) and fierce carnivores (dinosaurs that ate animals), as well as omnivorous dinosaurs that ate both plants and plants.
Biological habit
The oldest reptile fossils can be traced back to the "Pennsylvanian period" of Paleozoic (about 320 million years ago-280 million years ago). Tracing back to the source, it evolved from amphibians. Amphibian eggs need to be in water to start developing. Reptiles have evolved eggshells to prevent water from escaping from eggs. This major reform enables reptiles to survive without water. From 245 million years ago to the Mesozoic era 65 million years ago, reptiles became the master of the earth's ecology, so the Mesozoic era was also called the reptile era. Large reptile dinosaurs appeared in the early Mesozoic. The herbivorous confusing dragon is one of the largest land animals in size and weight. Spinosaurus is the largest carnivore on land. In addition, ichthyosaurs living in the sea, plesiosaurs and pterosaurs living in the air formed a complex and perfect ecosystem. Reptiles have multiplied on the earth for about 65.438+0.8 billion years. Among the animals of this era, dinosaurs are the most widely known. When people mention dinosaurs, they will see a huge and fierce animal. In fact, there are also small and docile species among dinosaurs. Dinosaurs belong to vertebrate reptiles and once lived in swamps and bushes on Mesozoic land. Their hind limbs are longer than their forelimbs and have tails. Many of them are carnivores and many are herbivores. Among them, the slower-developing species are similar to the oldest crocodiles and beaks, and the more developed species are similar to birds.
Dinosaur migration
For a long time, paleontologists were not sure whether dinosaurs migrated like birds or wildebeests. Because it may be threatened by Allosaurus (a distant relative of Tyrannosaurus Rex), it is not a far-fetched idea for giant herbivorous dinosaurs to migrate on the grassland. Now, researchers at the University of Colorado in the United States have proved for the first time that dinosaurs also migrated when their living environment deteriorated. Researchers used oxygen in tooth fossils to prove for the first time that dinosaurs migrated between flooded plains.
Dinosaur habit
The body structure of Tyrannosaurus Rex
Because dinosaurs are extinct, we can't study them by studying living animals, we can only rely on dinosaur fossils left over from the earth. Paleontologists speculate on the shape and habits of dinosaurs through the study of dinosaur fossils. According to their research, dinosaurs are like living animals: there are big ones and small ones; Some walk on two legs, and some walk on four legs; Some eat plants, some eat animals, and some eat both animals and plants; Some skin is smooth, and some skin has scales or bone plates. The similarity is that all dinosaurs had small brains (except some carnivorous dinosaurs) and laid eggs on land (all dinosaurs did).
Editing this dinosaur era
Dinosaurs lived on the earth for nearly 654.38+0.6 billion years. In such a long time, dinosaur fossils on earth
Many changes have taken place in our environment. The Pangu continent, which was originally connected as a whole, gradually drifted and split into the familiar form. After these earth plates drifted around the world, the climate environment changed because the light was no longer uniform and the heat conduction was blocked by the ocean. In the early dinosaur era, the dwarf shrubs composed of ferns were the main vegetation on the earth. Plate drift, coupled with climate change, has caused great changes in plant species on the earth. However, because these changes took place gradually over a long period of time, the animals growing in them can still adapt well. However, due to the intensification of crustal movement and frequent geological activities in the middle period of dinosaur era, the land climate changed. In the late dinosaur era, the climate became dry and cold. There is a desert on the earth, and the mountains are uplifted by the drift of the earth's plates. The deep valley sinks and the plates move the mainland in different directions, which makes a series of earth-shaking changes in the environment.
Editing this fossil discovery
Fossil excavation
dinosaur
In history, humans discovered dinosaur fossils very early. It was only because of the limited level of knowledge at that time that these fossils could not be correctly explained. According to legend, as early as 1700 years ago, dinosaur fossils were found in Wucheng County, Sichuan Province (then called Shu County of Bashu). But people at that time did not know that it was the remains of dinosaurs, but regarded them as the bones left by the legendary dragons. Long before Iguanodon (the first named dinosaur) was discovered in Mantels, Europeans knew that there were many grotesque huge animal bones buried underground. However, people didn't know them at that time.
Exact attribution
So it has always been mistaken for "the remains of giants." A researcher named Hastert from the University of Reading in prout-Garonne Province, according to the clues found in a historical novel "Mr. milken's Wife", after a long period of research and reading a lot of materials, announced that he finally found the following research results: 1677, a man named Plostegosaurus,
The Englishman in Garonne wrote a natural history book about Oxfordshire. In this book, prout Gallon describes a huge fossil leg bone found in a quarry in the parish of Karovilla. Prout-Garonne province drew illustrations for this fossil, and pointed out that this thigh bone is neither cow's, horse's, nor elephant's, but belongs to a giant bigger than them. Although prout-Garonne Province didn't realize that this fossil belonged to a dinosaur, or even associated it with reptiles, the specimen he recorded in writing and depicted by himself with illustrations has been identified by later paleontologists as the thigh bone of a dinosaur called Megalodon (now known as Bancrosaurus), and this fossil was discovered earlier than the first named dinosaur, Iguanodon, in Mantels 145 years. Therefore, Hastert thinks that prout-Garonne Province should be the first discoverer and recorder of dinosaur fossils in history.
Edit this dinosaur category
Classification It is biologically classified as a superfamily. The biggest difference between dinosaurs and other reptiles lies in the posture of standing and the way of marching. 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 the belt structure: the belt of sauropods is shot from the side, the pubic bone extends forward under the intestinal bone, and the ischium extends backward, similar to lizards; Very ugly. 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 the pelvis is radiant from the side (there are other differences). 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 medium-sized dinosaurs, such as Ban Long, the first giant dinosaur living on the earth, and Ankylosaurus living in the Early Jurassic. 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 Mamenxilong, which was produced in Sichuan and Gansu provinces of China in the late Jurassic. It consists of 19 cervical vertebrae and is the largest known animal in the world-Zhenlong or fragile double-chambered dragon. Theropod dinosaurs lived from the Late Triassic to the Cretaceous. They are all carnivorous dragons, walking on two feet, with sharp claws on their toes and well-developed heads, and they are the smartest one. There are teeth as sharp as daggers or knives in the mouth. Tyrannosaurus rex is a famous representative, and the others, such as Allosaurus and the southern behemoth, are also famous. 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. Tadinosaur
Children 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 Late Triassic to Cretaceous, and they were all vegetarian dinosaurs. Such as: hadrosaurs, Iguanodons, etc. Stegosaurus was a quadruped with an upright bone plate on its back and two or more pairs of bony spines on its tail. It mainly lived from Jurassic to early Cretaceous, and was the first large extinct dinosaur group. Its representatives are Stegosaurus and Kenterosaurus. The former is thought to live in the plain, while the latter is found in Tanzania. Ankylosaurus dinosaurs were short and stout, covered with bone decks, and ate plants, mainly living in the early Cretaceous. For example, Hailaerlong lived in continental Europe, Ankylosaurus lived in Britain, Baotou Dragon lived in the United States and Edmonton Dragon lived in Mongolia. 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. Among them are Triceratops, the docile herbivorous dinosaur protoceratops and so on. 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. 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 these two animals, called dinosaurs, are the closest relatives compared with all other reptiles.