Why are there dinosaurs?Why are there dinosaurs in the world?

Natural phenomena such as lightning constantly occur on the primitive earth, forming organic matter. Organic matter forms the most primitive cells through complex changes. Cells evolved to form dinosaurs

In 1842, the British paleontologist Charrhid Owen coined the term "dinosaur". The English dinosaur comes from the Greek deinos (meaning terror) and saurosc (meaning lizard or reptile). For Owen at the time, the term "scary lizard" or "scary reptile" meant a large extinct reptile.

In fact, not many dinosaurs were found at that time. Since the discovery of dinosaurs in Antarctica in 1989, there have been dinosaur remains on all seven continents around the world. There are at least 650 to 700 dinosaurs described in the world.

With the discovery of a large number of dinosaurs and the deepening of their research, the meaning of dinosaurs has changed qualitatively. The most fundamental change is that dinosaurs were not only extinct, gigantic ancient reptiles, but also ancient reptiles that could walk upright.

Some ancient reptiles, such as pterosaurs, ichthyosaurs, plesiosaurs, etc., which were contemporaries of the dinosaurs, were also huge and extinct animals. But they can't walk on land on two or four legs, so they're not dinosaurs. Some reptiles are crawling, with their abdomen close to the ground when they walk, and the limbs are supported on both sides of their bodies, such as turtles and crocodilesSome walk with their bodies slightly off the ground, but only for a short distance, such as an ancient crocodile called the Dragon Pike crocodile, as well as some modern crocodiles;In addition, dinosaurs can be the most successful in the history of biological evolution.

Therefore, we can say that dinosaurs were extinct terrestrial reptiles that lived about 23.5 billion to 65 million years ago and could walk upright with hind limbs.

Dinosaurs are the most adaptable creatures to the earth's environment and climate produced in that special period, so there are dinosaurs In fact, it is the principle of survival of the fittest, in that era, it should be the Triassic, Cretaceous and other periods, the earth's atmosphere and land environment have been suitable for the survival of this huge creature. Even before that there were ancient dragonflies, with individual wings up to 1 meter in length, in short, there were specific creatures at certain times.

Because it's a product of nature.

To facilitate research, dinosaurs can be divided into avian and non-avian dinosaurs. Among them, non-avian dinosaurs lived only in the Mesozoic era (Triassic, Jurassic and Cretaceous) and were all extinct 65 million years ago. This entry mainly introduces non-avian dinosaurs.

The muscular limbs, long tails, and massive bodies are some of the non-avian dinosaurs. They mainly inhabit woodlands or open areas on lakeshore plains (or coastal plains).

The discovery of dinosaur fossils has a long history. Long before the Mantels discovered the avian dragon, Europeans knew that there were many gigantic skeleton fossils buried underground. However, at the time, people did not know their exact attribution, so they were always mistaken for "the remains of giants".

It wasn't until Mr. and Mrs. Mantel discovered the avian dragon and compared it to the iguana that the scientific community initially determined that it was a lizard-like and long-extinct reptile. As a result, new types of dinosaurs and other ancient reptiles were discovered with names related to lizards, such as "whale-like lizards", "forest lizards", and so on. At the same time, because the fossils of these ancient animals that first attracted people's attention are often huge and strangely shaped, it is really terrifying.

It's just that there were dinosaurs in the past, and fossils show that dinosaurs have been on Earth for a long time. The crux of the matter is not why there were dinosaurs at all, but how dinosaurs came to be, which is still basically a mystery in the history of biological evolution. The call of the ancients, the world has to hear it, and the longest one may not have seen it today, wild animals and plants are scarce, only existing, decades later, people move, the botanical garden can be seen limited, sigh, regret that it is difficult to save the water and fire in the drips.

In the field of life evolution, human beings cannot do at least two things at present, one is to perfectly explain how various creatures in history came to be, and the other is to be unable to ** what kind of creatures will appear in the future. The former can be understood through fossil and molecular techniques, and the latter can be understood through environmental changes, but evidence of all aspects of evolution cannot be found in the former research, and it is difficult for the latter to accurately simulate the various factors that affect the changes and what the future environment of the earth will be. Neither will be 100% accurate.

As for why there are human beings in the world, we can make a better judgment through fossil and genetic analysis, after all, the history of human evolution is still relatively short, and the evidence such as fossils is relatively well preserved. There is a large amount of evidence that human beings have a single origin, modern humans originated in Africa 200,000 years ago, and began to migrate to other continents 780,000 years ago.

Asking why there are dinosaurs in the world cannot be explained, and the point of the question is not clear. To be sure, dinosaurs were also terrestrial creatures, and carbon-based biological macromolecules are a good example of this. As for how the evolutionary branches of various dinosaurs came about, there is still a lack of evidence.

In the course of evolution, human beings have killed the memories of ancient history one by one, which cannot be replayed, recovered, or recovered. But the development of science is never-ending, and there are still many things in our lives that cannot be explained by science for the time being, let alone things from ancient times.

Dinosaurs also evolved from single-celled organisms, and the earth evolved dinosaurs over a long period of time.

During the age of the dinosaurs, the oxygen content in the air on Earth was extremely high, and this ecological condition inevitably gave birth to giant animals.

The reason why there are dinosaurs is also because of evolution, and they did not appear suddenly, and how they came about cannot be confirmed with our current scientific capabilities, and I believe that the answer will be found soon.

Because dinosaurs are the evolution of lizards.

Unprecedented mass extinction Dinosaurs have successfully lived on Earth for hundreds of millions of years and have been the masters and powerful rulers of the planet. However, 65 million years ago, at the end of the Cretaceous period, they suddenly disappeared from all parts of the world. Along with the dinosaurs, a large number of other phyla and animals of different ecological conditions were extinct.

On land, crocodiles, lizards, etc. died on a large scale, and higher plants had 1 3 genera extinct. There are also many dead creatures in the ocean, prominent ones such as ammonites, arrowstones, foraminifera, corals, and supermicroorganisms. Famous relatives of dinosaurs, pterodactyls, plesiosaurs, ichthyosaurs, etc., also went with the dinosaurs.

Some scientists counted the number of genera of various phyla at the end of the Cretaceous and the beginning of the Tertiary period, and there were 2868 genera at the end of the Cretaceous period, and only 1502 genera in the early Tertiary period, accounting for 52%, indicating that about half of the organisms were extinct. If we look at the taxonomic units of organisms at the species level, the extinct species of organisms reach 75%, that is to say, about 2 3 organisms are extinct! Fossil data show that the extinction event at the end of the Cretaceous was global and occurred in a short period of time.

Among the extinct animals are those who walk on the ground, those that fly in the sky, and those that swim in the water, and there are not only large animals (such as dinosaurs), but also very small animals. In addition, there are plants. An unprecedented extinction!

It was not only the dinosaurs that disappeared in the extinction event 65 million years ago, but also a large number of other animals and plants, why did reptiles such as crocodiles, lizards, snakes, and turtles survive and continue to thrive until now? And the dinosaurs left only a few fossils? The extinction of dinosaurs is considered one of the top ten scientific mysteries of our time, and it is one of the major unsolved cases in the history of life on Earth.

Since the 70s of the last century, various theories and hypotheses about the great extinction have been promulgated, and there has been an unprecedented controversy. What kind of catastrophe happened that led to such an unprecedented extinction?

The appearance of the dinosaur is described as follows:

1. The body of the dinosaur is very long, more than 20 meters from head to tail, and it looks like a moving suspension bridge when it walks.

2. When I arrived at the gate of the dinosaur park, I saw a huge electric sculpture dinosaur at the door, which sometimes blinked its sparkling eyes, sometimes flicked its long tail, and sometimes roared loudly at the passing crowd. The tiles on the ground are also carved with Tyrannosaurus rex, triceratops, duck-billed dragon, diplodocus and so on, and they are very cute.

3. The ichthyosaur looks very much like today's dolphins, and the pterosaur looks like a soaring plane when it spreads its wings and flies high.

4. Bird-like dragons lived in the late Cretaceous period 80 million years ago, and lived in Erenhot, Inner Mongolia, China. Ornithosaurus was a sprinter with a bird-like mouth, and its diet consisted of insects, lizards, paddle fruits, and sometimes it would steal the eggs of other dinosaurs.

5. The Brontosaurus is a behemoth, its body weighs as much as six elephants, and it makes a roar every time it takes a step, like thunder.