Information about dinosaurs

dinosaurs are Mesozoic reptiles that appeared 245 million years ago and flourished 65 million years ago. Or a vague general term for dinosaurs and plesiosaurs and pterosaurs at the same time. Dinosaurs suddenly disappeared at the end of the Cretaceous period 65 million years ago, which became a mystery in the evolution history of life on earth. This mystery is still unsolved by no one. All the creatures of the earth in the past are recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata. In which a large number of bones or various shapes can be seen. However, in the Cenozoic strata that followed, there were no dinosaur fossils at all. It can be inferred that dinosaurs died out together in Mesozoic. There are many kinds of dinosaurs, and their shapes and habits are also quite different. Among them, the big ones can be as big as dozens of elephants combined; Small, but almost like a chicken. Dinosaurs are a kind of animals that lived about 235 million to 65 million years ago and could walk upright on their hind legs. They dominated the global terrestrial ecosystem for more than 16 million years. Most dinosaurs have been extinct, but the descendants of dinosaurs-birds have survived and multiplied to this day. In addition, in spoken language, dinosaurs refer to ugly women. The word "dinosaur" has two meanings in the dictionary: an ancient animal that lived hundreds of millions of years ago and is now extinct; (Internet language) a woman with bad looks in contemporary times. All dinosaurs have been extinct, but the descendants of dinosaurs-birds have survived and multiplied to this day. Dinosaur English ['dain? s? :] bel canto ['da? n? ,s? R]) is a kind of terrestrial animal that lived about p>5 million 3 dinosaurs

5 million to 65.95 million years ago and was able to walk upright on its hind legs. It is a group of diversified dominant vertebrates in Mesozoic. Most of them belong to terrestrial reptiles, but they can walk upright and dominate the global terrestrial ecosystem for more than 16 million years. The reason why it is said to be a vertebrate rather than a reptile is that dinosaurs were once classified as reptiles, but they did not conform to one of the basic characteristics of reptiles: the crawling way of walking and the cold-blooded animal that has been questioned all the time.

time of extinction

dinosaurs first appeared in the Triassic period about 24 million years ago, and died in the Cretaceous period about 65 million years ago. Dinosaurs eventually died out in the Cenozoic Paleocene 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 Iguanodon was discovered and compared with iguana that the scientific community initially determined that it was a group of extinct reptiles similar to lizards. In 1842, the English paleontologist Charles Owen coined the term "dinosaur". English dinosaur comes from Greek deinos (meaning horrible) Saurosc (meaning lizard or reptile). For Owen at that time, this "scary lizard" or "scary reptile" refers to a large extinct reptile (but it is not). In fact, not many dinosaurs were found at that time. Since the discovery of dinosaurs in Antarctica in 1989, dinosaur remains have been found in seven continents around the world. At present, there are at least 65 to 7 species (biological species) of dinosaurs described in the world. Later, scholars in China, Japan and other countries translated him as a dinosaur, because these countries have always had legends about dragons, and they think that dragons are the length of scale worms, and snakes are known as other names for dragons.

As I am only a student, I only know these ~ ~ I hope I can help you ~ ~ Responder: Lovely Sweetheart 62 | Grade II | 211-5-12 2:7

All dinosaurs have died out, but the descendants of dinosaurs, birds, have survived, and they have survived to this day. Dinosaur English ['dain? s? :] bel canto ['da? n? ,s? R]) is a kind of terrestrial animals that lived about p>5 million 3 dinosaurs

5 million to 65.95 million years ago and could walk upright on their hind legs. It is a group of diversified dominant vertebrates in Mesozoic. Most of them belong to terrestrial reptiles, but they can walk upright and dominate the global terrestrial ecosystem for more than 16 million years. The reason why it is said to be a vertebrate rather than a reptile is that dinosaurs were once classified as reptiles, but they did not conform to one of the basic characteristics of reptiles: the crawling way of walking and the cold-blooded animal that has been questioned all the time. Respondent: ∨ x1n9Love | Level 1 | 211-5-12 2:27

Dinosaurs are Mesozoic reptiles that appeared 245 million years ago and flourished 65 million years ago. Or a vague general term for dinosaurs and plesiosaurs and pterosaurs at the same time. Dinosaurs suddenly disappeared at the end of the Cretaceous period 65 million years ago, which became a mystery in the evolution history of life on earth. This mystery is still unsolved by no one. All the creatures of the earth in the past are recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata. In which a large number of bones or various shapes can be seen. However, in the Cenozoic strata that followed, there were no dinosaur fossils at all. It can be inferred that dinosaurs died out together in Mesozoic. All dinosaurs have been extinct, but the descendants of dinosaurs-birds have survived and multiplied to this day. Dinosaur English ['dain? s? :] bel canto ['da? n? ,s? R]) is a kind of terrestrial animal that lived about p>5 million 3 dinosaurs

5 million to 65.95 million years ago and was able to walk upright on its hind legs. It is a group of diversified dominant vertebrates in Mesozoic. Most of them belong to terrestrial reptiles, but they can walk upright and dominate the global terrestrial ecosystem for more than 16 million years. The reason why it is said that it is a vertebrate rather than a reptile is that dinosaurs were once classified as reptiles, but they did not conform to one of the basic characteristics of reptiles: the creeping way of walking, and the theory that cold < P > appeared in the time of extinction and blood animals has been questioned all the time. Dinosaurs first appeared in the Triassic period about 24 million years ago and died in the Cretaceous period about 65 million years ago. Dinosaurs eventually died out in the Cenozoic Paleocene 65 million years ago.

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 Iguanodon was discovered and compared with iguana that the scientific community initially determined that it was a group of extinct reptiles similar to lizards. In 1842, the English paleontologist Charles Owen coined the term "dinosaur". English dinosaur comes from Greek deinos (meaning horrible) Saurosc (meaning lizard or reptile). For Owen at that time, this "scary lizard" or "scary reptile" refers to a large extinct reptile (but it is not). In fact, not many dinosaurs were found at that time. Since the discovery of dinosaurs in Antarctica in 1989, dinosaur remains have been found in seven continents around the world. At present, there are at least 65 to 7 species (biological species) of dinosaurs described in the world. Later, scholars in China, Japan and other countries translated him as a dinosaur, because these countries have always had legends about dragons, and they think that dragons are the length of scale worms, and snakes are known as other names for dragons.

As I am only a student, I only know these ~ ~ I hope I can help you ~~

There are many kinds of dinosaurs, and their shapes and habits are quite different. Among them, the big ones can be as big as dozens of elephants combined; Small, but almost like a chicken. As far as food habits are concerned, there are docile herbivores < P > and fierce carnivores, and omnivorous dinosaurs < P > Dinosaurs are a kind of animals that lived about 235 million to 65 million years ago and could walk upright on their hind legs, dominating the global terrestrial ecosystem for more than 16 million years. Most dinosaurs have been extinct, but the descendants of dinosaurs-birds have survived and multiplied to this day. In addition, in spoken language, dinosaurs refer to ugly women. The word "dinosaur" has two meanings in the dictionary: an ancient animal that lived hundreds of millions of years ago and is now extinct. All dinosaurs have been extinct, but the descendants of dinosaurs-birds have survived and multiplied to this day. Dinosaur English ['dain? s? :] bel canto ['da? n? ,s? R]) is a kind of terrestrial animals that lived about p>5 million 3 dinosaurs

5 million to 65.95 million years ago and could walk upright on their hind legs. It is a group of diversified dominant vertebrates in Mesozoic. Most of them belong to terrestrial reptiles, but they can walk upright and dominate the global terrestrial ecosystem for more than 16 million years. The reason why it is said to be a vertebrate rather than a reptile is that dinosaurs were once classified as reptiles, but they did not conform to one of the basic characteristics of reptiles: the crawling way of walking and the cold-blooded animal that has been questioned all the time. Respondent: Enthusiastic User | May 15, 211 8: 4

The first dinosaur bone fossil was discovered and collected by Robert prout, keeper of the Oxford Museum in England in 1677. After more than a hundred years, many explorers and scholars have discovered and studied the fossils belonging to dinosaurs, but almost none of them have been correctly identified.

in p>1841, paleontologist richard owen first put forward the word "dinosaur" based on some fossil specimens of large reptiles, which came from the Greek words "deinos" (meaning horrible) and "sauros" (meaning lizard) and was translated as "dinosaur" by Japanese and Chinese scholars.

after the concept of "dinosaur" came out, scholars made detailed observation and identification of dinosaur fossils found, and carried out further excavation work. The excavation of Asian dinosaurs was not carried out until after the 2th century. The earliest dinosaur fossils in China were discovered in 192 (Heilongjiang), and then a large number of dinosaur fossils were discovered in many parts of the country, including Lufeng in Yunnan, Laiyang in Shandong, Zigong in Sichuan, Tibet and Inner Mongolia. Lufeng and Zigong also established dinosaur museums respectively, and in 1991, the "Lufeng First Dinosaur Festival" was held. China can be called "a dinosaur country in the world".

Up to now, there are more than 2, dinosaur fossils (including bones, teeth, skin, eggs, feces, footprints, etc.) excavated all over the world. According to the identification, there are more than 8 species in more than 35 genera of 2 orders, 7 suborders (some scholars believe that the number of dinosaurs that have survived on the earth is between 9 and 1,2 genera), and there are more than 8 genera and more than 1 species in China.

The earliest dinosaur fossils that have been excavated are about 23 million years ago. It is generally believed that dinosaurs were differentiated from pseudocrocodiles among the first crocodiles. At first, dinosaurs were some bipedal carnivorous dinosaurs. By the end of Triassic, the evolutionary branch of dinosaurs was basically established. By the end of Jurassic, dinosaurs developed greatly, surpassing the pioneers of Triassic in species and quantity, and became the real rulers on the earth. Extensive adaptive radiation has also appeared.

"dinosaur" is not a taxonomic term, but a popular name. Dinosaurs are divided into two groups:

1. The main feature of sauropods (sauropods) is that the structure of the bones, ischium and pubis that make up the belt is similar to that of other reptiles, that is, the belt with three shots or three shots. It is divided into two suborders:

(1) theropod: Tyrannosaurus Rex, Deinonychus, Leptosaurus, Leptosaurus, etc.

(2) sauropod: Liang Long, Lei Long, Lufenglong, Mamenxilong, etc.

2. The main feature of ornithoptera is that the bone structure of the belt is similar to that of birds, with the pubic bone pointing backward, that is, a four-shot or four-put belt, and in addition, it has anterior teeth and buccal muscles. It is divided into five suborders:

(1) ornithopoda: Iguanodon, Duckbilled Dragon, etc.

(2) Ceratosaurus: protoceratops, Ceratosaurus, Parrotbill, etc.

(3) Ankylosaurus: Nodulosaurus, Spinosaurus, Ankylosaurus, etc.

(4) stegosaurus: stegosaurus, etc.

(5) Leo orders: pachydantosaurus, etc.

dinosaurs were all extinct in the late Cretaceous of Mesozoic-the early Paleocene of Cenozoic 6-7 million years ago. This ancient animal group, which has lived on the earth for more than 1 million years, mysteriously disappeared on the earth, causing many scholars to speculate and explain its reasons, and there is no conclusion yet. There are several explanations that still have a place in today's scientific circles: asteroid impact theory (Bekele theory), periodic extinction theory (Nemesis theory), climate deterioration theory, community succession theory, etc. The main reason why these explanations are not recognized is that they can't justify themselves and can't perfectly explain why dinosaurs became extinct in about 5 ~ 1 million years. The reasons for the extinction of many reptiles, such as dinosaurs, are described in the textbook Zoology of junior middle school, which belongs to the theory of climate deterioration and is a gradual change theory. Skeptics believe that dinosaurs have formed considerable adaptability to various environments in the long-term evolution process, otherwise they would have been eliminated. The deterioration of the earth's climate should be gradual or local, and dinosaurs seem to be able to adapt to it slowly or avoid it. In the early and middle Mesozoic, there were many major changes in landforms and climate, and dinosaurs were not greatly affected. Even if the deterioration of the earth's climate would lead to the death of dinosaurs, it would be partial. This is not the case all over the world. There are still some small areas where the climate has not changed much, and the dinosaurs there will not be extinct at the same time as the dinosaurs elsewhere. In short, the real reason for the extinction of dinosaurs is still unclear, and I believe that the mystery of the demise of dinosaur families will be solved one day.

For nearly half a century, scientists have accumulated some data on the biological characteristics of dinosaurs.

Dinosaur's limbs (especially belts) are similar to those of mammals (that is, they stand upright under their bodies and can walk or run "strutting" on the ground. Dinosaurs of average size (several meters to more than ten meters in length) usually have a stride of about 2.75 ~ 5 meters and can reach 5 ~ 8 meters when running; The running speed of small dinosaurs can reach 35 ~ 4 km/h, the running speed of larger dinosaurs can reach 15 ~ 2 km/h, and the slowest one is only 3.5 km/h.

Most dinosaurs were herbivores, and they ate a lot. sauropods weighing several tons to dozens of tons ate more than 1 kilograms a day, even more than one ton. There were few kinds and numbers of carnivorous dinosaurs. According to statistics, only 3 ~ 5 of every 1 dinosaurs were carnivorous dinosaurs.

dinosaurs are oviparous animals, and a few of them may be oviparous. During the reproductive period, males often fight for females or seduce their spouses with euphemistic guttural sounds. Eggs are 8 ~ 3mm in diameter and 2 ~ 7mm in shell thickness. Most of them are hatched by sunlight, and a few may hatch like hens. Some newly hatched young dinosaurs are well developed and can live freely.