What are the mysteries about dinosaurs? As the title suggests, thank you

1. Types of dinosaurs: At present, the number of dinosaurs found has exceeded 200 and can be divided into two categories: carnivorous and vegetarian.

The most familiar among carnivorous people is the Tyrannosaurus rex, because it can be said to be the most ferocious dinosaur among dinosaurs, so it got the name "Tyrannosaurus rex". There are many vegetarian dinosaurs, so I won't introduce them here. 2. Dinosaur habits:

Dinosaurs like to live in groups, in a group, and they are very "polite". When the small dinosaur is eating, if there is a big dinosaur, the small one will definitely let the big one, not only that, but the old one will also let the young one. 3. The mystery of the extinction of the dinosaurs:

The extinction of the dinosaurs remains a mystery to this day. However, there are now two speculations about the extinction of dinosaurs: one is that an asteroid hit the earth, smoke enveloped the earth, and the dinosaurs were all extinct before the sun was shining.

Another is that there was an acid rain at that time, and the dinosaurs and eggs were corroded and became extinct. Whether this statement is correct remains to be further examined. 4. How dinosaurs became fossils:

When the dinosaur died, the flesh rotted and was buried in the ground, and later, the soil hardened and the dinosaur skeleton became a fossil. 5. My Thoughts: In "The Mystery of Dinosaur Extinction", I thought:

There is also a possibility that the dinosaurs became extinct because some animals stole dinosaur eggs and made the dinosaurs extinct. But that's just my opinion, but it's possible.

There are still scientists who believe that some dinosaurs turned into birds. In 1973, Ostrum put forward the theory that "birds may have evolved from dinosaurs", which caused a sensation in the world paleontological community. The dinosaurs that have been found in the past are relatively large, and no dinosaurs smaller than Archaeopteryx have been found.

However, in 1999, a microraptor (Zhao's microraptor) was discovered in Liaoxi, China, which was only 30-40 centimeters long, much smaller than Archaeopteryx (the size of a crow), the smallest known dinosaur (fossils show that it was covered with feathers and had four wings, which was very similar to a bird). The smaller size of some species of dinosaurs created important conditions for dinosaurs to fly into the blue sky. Just think:

If all the Void Bone Dragons had evolved into big ones, then birds probably wouldn't have appeared. Experts now believe that birds evolved from dinosaurs of the genus dinosaurs, and that the characteristics of these dinosaurs are closest to those of birds. Microraptor is a small, delicate dinosaur.

According to research, the old-timers of the Void Bone Dragons all grew relatively large, but over time, some of them evolved in the process of evolution, some of them evolved to large sizes, and some to small ones. The type that evolved to the small eventually evolved dinosaurs that could break free from the earth's gravity and fly into the blue sky - birds.

1. The discovery of dinosaurs.

Although dinosaur fossils have been on Earth for tens of millions of years, it wasn't until the 19th century that people knew that such a strange animal once existed on Earth. The first dinosaur fossil was discovered by a British physician named Gideon Mantel, and the term "dinosaur" was coined by the British paleontologist Chad Owen.

2. The shape of the dinosaur.

The common characteristics of dinosaurs include: (1) the posterior frontal bone is missing. (2) The humerus has a low triangular crest, attached to the sternoclavicular deltoid muscle, and the length is about 1 3 to 1 2 (3) There is a protruding mass at the back of the intestinal bone, and the acetabulum is perforated.

4) The tibia has a broad terminal edge with a posterior flange. (5) The talus has an obvious superior protrusion that fits the tibia.

3. The tallest and heaviest dinosaurs.

The tallest and heaviest dinosaur was the long-necked giant dragon Giraffatitan Brancai (formerly known as Brachiosaurus brucei). Fossils of the long-necked dragon were found in Tanzania between 1907 and 1912. A skeleton model of a group of similarly sized individuals, which is on display at the Humboldt Museum in Berlin, is 12 meters tall and 12 meters long, and is expected to weigh between 30 and 60 metric tons of living animals.

4. The longest dinosaur.

The longest dinosaur, the 27-meter-long diplodocus, was discovered in Wyoming, USA, in 1907 and is now on display at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.

5. Close relatives of dinosaurs.

The Archaeopteryx discovered in 1861 (it was thought to be the earliest bird, but recent studies suggest that it may have belonged to the primitive dinosaur class) is morphomorphically similar to the Aeopteryx, except that the fossils of Archaeopteryx have obvious traces of feathers, and in fact a considerable number of carnivorous dinosaurs have primitive feathers, suggesting that dinosaurs may have been close relatives of birds.

Since 1970, many studies have reported that modern proven-bred birds are likely to be direct descendants of theropod dinosaurs, and recent studies have tended to classify birds directly as hypoolastosaurs (including Tyrannosaurus rex, oviraptorosaur, dinosaur, etc.).

Crocodiles are modern relatives of another group of dinosaurs, but they are more closely related to non-avian dinosaurs than birds. Non-avian dinosaurs, birds, and crocodiles all belong to the Archosaurus clade, which first appeared in the Late Permian and became the dominant fauna in the Middle Triassic.

Appearance characteristics of dinosaurs: Dinosaurs are large in size overall. By the standard of dinosaurs, sauropods are the giants of them.

During the long age of dinosaurs, even the smallest sauropods were larger than the other animals in their habitat, and the largest sauropods were several orders larger than any animal that appeared on the surface.

The smaller, fast-moving dinosaurs evolved a trait that can also be seen in modern animals: thin-walled bones. The bone resembles a hollow tube, with a thin outer wall made up of heavy bone, which is much lighter bone marrow.

Fast-moving herbivorous dinosaurs, such as Oak Tree Dragon, had this thin-walled long bone. We can assume that this skeleton is meant to reduce weight and thus gain greater speed when escaping from predators.

Growth and reproduction

Scientists have found not only the bones of dinosaurs, but also the nests and eggs they left behind. These dinosaurs were all small ceratosaurs, Protoceratosaurus. When alive, it was the size of a modern-day sheep.

Its eggs are cob-ovate, about 75 cm wide and 15 cm long, with up to 30 eggs, arranged in a spiral shape in the nest with the tip of the egg pointing inward.

The nest is located in a depression in the sand, as Protoceratosaurus lived in a sandy place. Many female dragons seem to lay eggs in the same set. By chance, in one of the nests, an egg-eating dinosaur was found, the fossilized skeleton of an egg-stealing dinosaur.

It seems that the animal was crushed to death by a sandstorm when it attacked the nest. Since then, eggs of many other species of dinosaurs have been discovered.

1.Dinosaurs are a general term for a class of reptiles that appeared in the Mesozoic era. Strong limbs, long tails, and huge bodies are portraits of most dinosaurs. It mainly inhabits woodlands or open areas in lakeshore plains.

2.In 1841, British scientist Richard Owen studied several fossilized bones of lizards, which he believed were left by some prehistoric animals, and named them dinosaurs, which means "terrible lizards". The sudden disappearance of dinosaurs at the end of the Cretaceous period, 65 million years ago, has become a mystery that remains unsolved in the history of the evolution of life on Earth.

Past life on Earth is recorded in fossils. Many dinosaur fossils have been found in Mesozoic strata.

3.A large number of bones of various shapes can be seen. However, in the subsequent Cenozoic strata, fossils of non-avian dinosaurs did not appear at all.

It is presumed that non-avian dinosaurs became extinct together during the Mesozoic Era. Now only the birds remain. Most scientists agree that "birds belong to dinosaurs".

1. Dinosaurs are a general term for a class of reptiles that appeared in the Mesozoic Era, and their vigorous limbs, long tails and huge bodies are the portrayals of most dinosaurs. They mainly inhabit woodlands or open areas on lakeshore plains.

When British scientist Richard Owen studied several fossilized lizard bones, he thought they were left by some prehistoric animal and named them dinosaurs, which means "terrifying lizards". The dinosaurs suddenly disappeared at the end of the Cretaceous period 65 million years ago, becoming a mystery in the history of the evolution of life on Earth, which is still unsolved. All of the earth's past creatures are recorded in fossils.

In the strata of the Mesozoic era, many dinosaur fossils have been found.

3. A large number of bones or various shapes can be seen. However, in the Cenozoic strata that followed, there were no fossils of non-avian dinosaurs at all, which suggests that non-avian dinosaurs became extinct together during the Mesozoic Era, and that only birds remain today, and most scientists agree that "birds belong to dinosaurs".