In Argentina, 1979, a protosauropod named Latarosaurus was found, which was about 20 cm long, just a little bigger than a mouse! But so far, only one such skeleton fossil has been found, probably a newly hatched baby dragon. A paleontologist speculated that this adult may be as long as six meters. But before the real adult rat dragon was discovered, it was just speculation! Among the known dinosaur species, the smallest adult dragon is the beautiful jaw dragon, about the size of a chicken.
The ugliest dinosaur:
Blackheads are the ugliest of those ugly dinosaurs. Pacitasaurus belongs to the dinosaur with a protruding top. Its skull is covered with an arc-shaped bone plate about 23 cm thick. Around this bulge, rows of small tumors and mucro surround the smooth hills, just like a tumor. Its front edge looks like it has been tortured by some unspeakable bone disease, and its nose is covered with tumor-like protrusions and thorns. These surrounding tumors and spinous processes make the protruding part of the head look like it has been shaved.
The longest dinosaur:
Liang Long is about 27 meters long. However, for the time being, the two kinds, nicknamed Super Dragon and Dragon, will be longer if all skeletons are excavated. The length of these two species is estimated to be 35 meters.
The heaviest dinosaur:
Brachiosaurus is estimated to weigh between 63 and 72 metric tons (70-80 tons). It needs strong limbs to support its body.
The widest dinosaur:
Long Kuan, a tank car crawling in Ankylosaurus dinosaur world, is about five meters long, although its body length is no more than ten meters.
The oldest dinosaur:
The earliest known dinosaur was a bipedal carnivore named Southern Cross Dragon. It appeared in the Middle Triassic, with a body length of about 1.5 m and a weight of about 30 kg.
Dinosaur with the biggest claws:
Deinonychus is a strong carnivorous dinosaur. Its claws are the largest dinosaur claws found so far. The outer arc length of claw is 3 1 cm.
The largest carnivorous dragon:
Tyrannosaurus rex is the largest carnivorous dinosaur. Adult Tyrannosaurus rex can reach 14 meters in length and weigh about 8 tons. It is the overlord of the dinosaur world.
The smartest dinosaur:
As far as the ratio of body to brain is concerned, sawtooth dragon has the largest brain and well-developed sensory organs, so it is considered as the smartest dinosaur.
The fastest dinosaur:
The bird-running dragon may be the fastest dinosaur, with a speed of over 70 kilometers per hour.
The largest dinosaur:
The largest dinosaur known is the sauropod vibrosaur (information is not available yet, please provide it). It is about 40 meters long and weighs 5 1 ton.
Dinosaur with the most teeth:
The plant-based hadrosaurs had about 960 teeth, more than any dinosaur.
The stupidest dinosaur:
The giant stegosaurus had a very small head and a brain the size of a walnut, so scientists thought they were stupid dinosaurs.
Dinosaur with the largest egg:
The dragon egg with high spine is about 30 cm in diameter. An egg that big can hold a volume of 3.3 liters. The eggshell is about 2 cm thick.
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dinosaur
Explanation 1: Girls who are not good-looking are often called "dinosaurs" on the Internet.
Explanation 2: Mesozoic creatures. described below
Dinosaurs ... are Mesozoic reptiles, which appeared 245 million years ago and flourished 65 million years ago. Dinosaurs suddenly disappeared in a certain period, which became a mystery in the evolution history of life on earth, and no one has solved it so far. In the past, all living things on the earth were recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata. A large number of bones or various shapes can be seen in it. However, in the subsequent Cenozoic strata, there were no dinosaur fossils at all. It can be inferred that dinosaurs died out together in Mesozoic.
The real reason for the extinction of dinosaurs has been debated since ancient times, but there is no definite statement, so it is still an unsolved mystery. Here are only some well-known statements as follows:
1. meteorite collision theory:
65 million years ago, a huge meteorite hit the earth, making the dinosaurs that lived in King's Landing 1 100 million years extinct. This theory was put forward by four scientists, including Dr. Luis Albales of the University of California, Berkeley.
This huge meteorite is about ten kilometers in diameter. The crater caused by the impact is 200 kilometers in diameter. The energy generated by the impact, if converted into yellow powder, is equivalent to one million tons. Dust diffuses into the stratosphere through the atmosphere. It caused the darkness of the earth for months. During this period, many creatures, led by dinosaurs, became extinct.
2. Comet collision theory;
The "comet collision theory" began with the argument that "the extinction of paleontology occurs every 26 million years" published by paleontologists David Laup and John Sepkowski. Louis Albalez gave this argument and his own theory to the astrophysicist-Charlie Murat La. Later, Miao La thought that comets were periodically pushed to the earth because of the gravity of the solar nemesis.
3. Theory of orogeny;
At the end of Cretaceous, the swamp was dried up by orogeny, and many dinosaurs whose home was swamp could no longer survive. Because of the changes in the post-Qi Dynasty, plants also changed, and herbivorous dinosaurs could not adapt to new foods and died out one after another. The herbivorous dinosaurs became extinct, and the carnivorous dinosaurs also lost their dependence. As a result, they also became extinct. This extinction process lasted 65,438+0,000-20 million years. By the end of Cretaceous, it was extinct on the earth.
4. Climate change theory:
As a result of plate movement, ocean currents change, which leads to great changes in climate. The cold climate killed plants and dinosaurs died for lack of food.
5. Volcanic fire theory:
Because the volcano erupts, it spews a lot of carbon dioxide, causing the global greenhouse effect and causing food death. Moreover, the volcano spewed fire, resulting in the release of a large amount of salt, the destruction of the ozone layer, harmful ultraviolet radiation on the surface, resulting in extinction.
The theory of ocean ebb tide with intransitive verb;
According to Barker, when the ocean ebbs and the land borders, creatures contact each other, which leads to the extinction of some species. Kangaroos, for example, can live in the island continent of Europe, but they will die if they meet other animals in South America.
In addition to this relationship between eating and being eaten, there are also infectious problems such as diseases and parasites.
Seven. Warm-blooded animals say:
Some people think that dinosaurs were warm-blooded animals, so they could not bear the cold weather in the late Cretaceous and could not survive. Because even if dinosaurs were warm-blooded, their body temperature was still not high, probably similar to that of living sloths, and to maintain such a body temperature, they could only live in a tropical climate. At the same time, the dinosaur's respiratory organs were not perfect and could not fully supplement oxygen. They don't have thick hair to avoid hypothermia, but they easily lose a lot of heat from their long tails and feet. The difference between warm-blooded animals and cold-blooded animals is that if the body temperature drops below a certain range, it will consume physical energy to raise the body temperature and the body will soon become weak. They are too big to go into caves to avoid the cold, so if the cold days last for a few days, they may freeze to death because of exhaustion.
Eight. Fratricidal theory:
Some people think that the real reason for the extinction of dinosaurs is the result of their killing each other-carnivorous dinosaurs ate herbivorous dinosaurs, carnivorous dinosaurs increased, herbivorous dinosaurs naturally became less and less, and finally disappeared. Carnivorous dinosaurs killed each other because they had no meat to eat, and finally died together.
Nine. Oppression theory:
The rapid increase in the number of dinosaurs led to the extinction of herbivorous dinosaurs with limited plants, and then carnivorous dinosaurs that ate herbivorous dinosaurs died because of lack of food. (Doubt: Why did dinosaurs suddenly increase after about 200 million years of ecological balance? The key to the establishment of this theory has also directly caused many scholars to review the reasons for the abnormal increase in dinosaur production. )
10. The mammalian prisoner said:
In the second half of Mesozoic, the ancestors of mammals existed. According to fossil records, mammals at that time were very small and the number was very limited. It was not until the late Cretaceous that the number began to increase rapidly. It is speculated that they are omnivores whose main food is insects. These small mammals have been eating dinosaur eggs since they found them.
My opinion: Is this really the case? If mammals beat dinosaurs, then with the increase of mammalian fossils, dinosaur fossils should gradually decrease, but in fact there is no such phenomenon of fossil alternation. In other books, the real increase in mammalian fossils was after the end of the dinosaur era. Moreover, dinosaur fossils suddenly disappeared. Therefore, the theory that dinosaurs were extinct by mammals cannot be established. )
1 1. The aging theory of species;
People think that the dinosaur's body was too big because it flourished for hundreds of millions of years. Moreover, bones such as horns are also extremely developed, which causes great inconvenience to life and eventually leads to extinction.
The most representative dinosaur brontosaurus is 25 meters long and weighs 30 tons. Because of his huge size, he lost his ability to survive. In addition, Triceratops and others also went to the road of self-destruction because of the increasing number of three horns and the unusually developed bones to protect their heads.
My opinion: not all dinosaurs are so huge, but there are also small dinosaurs with a body length of only about one meter. In addition, there are dinosaurs with bones like deer that can run briskly. But why did this dinosaur die out at the same time? Moreover, in cold-blooded animals, abnormally developed bones and other parts are considered to be able to absorb external temperature and release internal heat to regulate body temperature, which has very favorable functions. Therefore, I suspect that the extinction of dinosaurs was due to the aging of species. )
Twelve. Alkaloid theory:
According to this theory, flowering plants began to appear in the last period of dinosaur existence, that is, the Cretaceous period, and some of them contained toxic alkaloids. Dinosaurs died of poisoning because of eating a lot of food. Because mammals can distinguish poisonous plants through taste and smell, but dinosaurs don't have this ability.
However, plants containing alkaloids did not suddenly appear in the late Cretaceous, but were already visible five million years before the extinction of dinosaurs. This theory can't explain why dinosaurs survived during this period.
In addition to the above twelve statements, there are other less well-known statements, such as "infectious diseases", "radiation from the universe or supernova explosion", "not taking Noah's Ark" and "vibration theory of the solar system". As for which is the best statement, it depends on everyone's thoughts, and there is no right or wrong. After all, the mystery of dinosaur extinction has not really been solved!
The oldest reptile fossils can be traced back to the Paleozoic Pennsylvanian period (365,438+million years ago-275 million years ago). Tracing back to the source, it evolved from amphibians. Amphibian eggs need to develop in water. Reptiles evolved eggshells to prevent water from escaping. This major reform enables reptiles to survive without water.
By the Mesozoic era from 225 million years ago to 65 million years ago, reptiles had become the masters of the earth, so the Mesozoic era was also called the reptile era. Large reptile dinosaurs appeared in the early Mesozoic. Herbivorous Liang Long and Lei Long are the largest land animals. Tyrannosaurus rex is a carnivorous dinosaur. There are also ichthyosaurs living in the sea and pterosaurs living in the air.
Reptiles have multiplied on the earth for about 654.38+0.5 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 dinosaurs among dinosaurs.
Dinosaur is a kind of vertebrate reptile, which was once produced in Mesozoic land swamp and had a long neck and tail. The hind limbs are longer than the forelimbs and have tails. Some of them are carnivorous, and some are herbivorous. They are huge and can be considered as the largest terrestrial animals. At the lower level, species are like the oldest crocodiles and beaks, and at the higher level, they are slightly similar to birds.
The study of dinosaurs depends entirely on fossils. Paleontologists infer their shapes and habits from their fossils. According to paleontologists, dinosaurs are like living animals: there are big ones and small ones; Some people walk on two legs; Some people walk on four legs; Some eat plants, some eat animals; Some skin is smooth, and some skin has scales or bone plates. The similarity is that all dinosaurs have small brains and lay eggs on land (as do all reptiles).
(1) Lei Long:
Some dinosaurs had huge bodies, such as Lei Long. During the Jurassic period, the climate on the earth was warm and humid, and there were lush forests everywhere. Because of these rich plant foods, herbivorous dinosaurs flourished. After that, Lei Long was also active in the North American Plain.
Lei Long weighs about 35 to 50 metric tons and has thick legs like a trunk. Long neck, standing as high as seven stories, can be said to be the largest animal in the world. Although Lei Long's body is surprisingly large, her temperament is very gentle. She usually feeds on plants in temperate forests and sometimes walks into swamps. Because of the buoyancy of water, she can reduce the heavy burden on her body and avoid the attack of fierce carnivorous dinosaurs like Allosaurus.
(2) three dragons:
Bone plates and fragments of Stegosaurus and Ceratosaurus can only be passively defended and cannot fight back. It was not until the Rocker Dragon appeared that the situation gradually changed. Lei Long is the largest of all sauropods. It has two spear-shaped horns on its head, and the other horn protrudes between its eyes and nostrils. Such a sharp weapon, even the most terrible carnivorous dinosaur will give it three points.
(3) Stegosaurus:
Stegosaurus appeared10.5 billion years ago, characterized by two ribs on its back and spikes on its tail. Stegosaurus was a herbivorous dinosaur and moved slowly. Its bone plate and spikes on its tail became the best weapon against carnivorous dinosaurs.
(4) Ankylosaurus:
Stegosaurus was protected by a bone plate, but it was still fragile where the bone plate could not cover it. When stegosaurus gradually disappeared, Ankylosaurus (armadillos) covered with bone plates took its place. Ankylosaurus is like an invincible tank car, even Tyrannosaurus Rex can't help it.
(5) Tyrannosaurus Rex:
Tyrannosaurus Rex is the largest and most ferocious carnivorous dinosaur. Tyrannosaurus rex appeared at the end of the dinosaur era, about 80 million years ago. Tyrannosaurus rex's body is 14 meters high and weighs about 10 metric ton. Its hind feet are thick and strong, and can even support a rhinoceros.
From the fossils of Tyrannosaurus Rex, it is found that every tooth is as big as an adult's palm, and even its eyes are bigger than a human head. Although most of the body is surprisingly large, the forelimbs of Tyrannosaurus rex are so small and short that it is impossible to send food into its mouth. The killer dragon has the same habit as Tyrannosaurus Rex, and it is a fierce animal.
[6] duck crown dragon:
Like Tyrannosaurus rex, the duck-crowned dragon appeared at the end of the dinosaur era. The most special thing about the duck-crowned dragon is its head. Its flat and long jawbone looks like a duck's mouth, so it has the name of duck-crowned dragon. In the past, people thought that the life of the duck-crowned dragon was similar to that of a duck. It swims in the water and feeds on plants in the water. Later, when scientists studied the fossils of the duck-crested dragon, they found that they did not eat aquatic plants for a living, but lived in trees on the shore, and the goose-crested dragon had the same habit.
Who first discovered dinosaurs?
mantel pick-up
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, and especially likes collecting and studying fossils. In addition to practicing medicine and treating diseases, he often takes his wife to climb mountains and wade to find and collect fossils, and his footprints have traveled all over the ravines and ridges with exposed rock layers around him. With the passage of time, Mrs Mantell has also become a "friend of nature" and a master of fossil collection.
iguanodon
1822 One day in March, it was very cold, but Mr. Mantel went out to see the patient as usual. The lady is waiting for her husband to come back at home. 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 meet him in the direction of his house call. She walked on a road under construction, and the newly cut steep walls on both sides of the road exposed layers of rocks. She walked habitually, observing the newly exposed rock formations on both sides. Suddenly, a shiny thing caught her attention. "What is this?" While talking to herself, she stepped forward to watch carefully. Wow! It turned out to be some strange-looking 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.
Later, Mr mantel went home. He was shocked when his wife showed him the newly collected fossils. He has seen many ancient animal tooth fossils, but none of them can be similar to such a big and strange tooth.
Soon after, Mr mantel found many such tooth fossils and related bone fossils near the place where the fossils were found. In order to find out what animals these fossils belong to, Mr Mantell took them to Ye Wei, a French naturalist, and asked the most famous scholars in the world to identify them.
To tell the truth, Ye Wei has never seen this kind of fossil, and all the books and papers written by senior scientists he has read have never mentioned this kind of fossil. However, Ju Ye Wei made a judgment based on his rich knowledge of zoology. He thinks that the teeth are rhinoceros's and the bones are hippopotamus's, and he is not too old.
Mr Mantel is very skeptical about the evaluation of living in Ye Wei. He thinks that the conclusion of living in Ye Wei is too hasty. He decided to continue his research. From then on, whenever he had the opportunity, he went to museums all over the country to compare specimens and consult materials.
One day two years later, he met a naturalist who worked in the Royal College Museum in London. He is studying an iguana, a modern lizard living in Central America. Therefore, 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. Overjoyed, Mr mantel concluded that these fossils belong to an extinct ancient reptile similar to an iguana and named it "the teeth of an iguana".
Later, 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 was translated into Iguanodon.
So please remember: Iguanodon is the earliest recorded dinosaur in the history of science. At the same time, don't forget the name Mantel and his wife who loves nature.
Who first discovered dinosaurs?
The story of prout-Garon-Garon
Mrs Mantell found the story of dinosaurs really romantic. Mr Mantell was able to explore the ownership of dinosaurs with a rigorous and realistic attitude, which was indeed the first step for human beings to study dinosaurs scientifically and understand them.
But in history, humans have long discovered dinosaur fossils, but at that time, due to limited knowledge, they could not explain them correctly.
As early as 1000 years ago, during the Jin Dynasty in China, dinosaur fossils were discovered in Wucheng County, Sichuan Province. 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.
Based on the clues found in a historical novel "Mr. milken's Wife", a researcher named Huster from the University of Reading in England recently announced that he had finally discovered the following facts: 1677, an Englishman named prout-Garonne-Garonne wrote a natural history book about Oxford. In this book, prout Gallon Gallon describes a huge fossil leg bone found in a quarry in the parish of Karovilla. Prout-Garonne-Garonne drew a good illustration of 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-Garonne Province didn't realize that this fossil was a dinosaur, or even associated it with reptiles, the specimen he described with words and illustrations has been identified by later paleontologists as the thigh bone of a dinosaur called Megalodon, and this fossil was discovered 145 years before Iguanodon was discovered in Mantels. Therefore, Hastert thinks that prout-Garonne-Garonne should be the first discoverer and recorder of dinosaur fossils.