Dinosaur (English name: Dinosaur) refers to the most recent common ancestor of Triceratops , modern birds and Diplodocus and all its descendants. Dinosaurs can be divided into avian and non-avian dinosaurs. Among them, non-avian dinosaurs only lived in the Mesozoic Era (Triassic, Jurassic, and Cretaceous), and all dinosaurs became extinct 65 million years ago.
So where did the dinosaurs come from?
During the ancient period, about 570 to 248 million years ago, fish first evolved from soft boneless creatures with internal skeletons, and then fish evolved into two creatures walking on land. species, and then evolved into reptiles. One of these reptiles evolved into archosaurs.
The dinosaurs at that time were smaller bipedal carnivores, but large four-legged plant-eating species also evolved at the end of the Triassic. The earliest archosaurs lived on the plateau and were small or medium-sized carnivores. Because catching prey required running quickly, the archosaurs developed different postures. Among them, the dinosaurs gradually stood upright with their limbs. . In order to catch prey, speed is particularly important. The body is lifted up by the forelimbs so that the tail serves as a balancer to effectively achieve a standing posture. The entire body is hinged on the belt, so it developed into a reptile dinosaur with a special shape.
Why did the dinosaurs survive for hundreds of millions of years without creating civilization and evolving into advanced creatures?
In fact, the innate conditions of dinosaurs are not good. We humans evolved from ancient apes , and forest ancient apes have an appearance between humans and apes, and can walk on four legs or two legs. The reason why humans can evolve into advanced creatures is that they have gone through a series of evolutionary processes including walking upright, learning to use tools, using fire, and increasing their brain capacity.
On the contrary, from the beginning, their ancestors of dinosaurs wanted to become stronger. They did not think about walking upright, using tools, and other things that required thinking. They chose brute force and relied on their powerful bodies to obtain food and survive. They have never thought about using their hands to create miracles. If they don’t use their hands, they can’t use tools, they can’t make fire, and they can’t evolve their brains.
Another reason is that the dinosaurs at that time were too powerful. They were at the top of the world's food chain at that time. There were almost no creatures on the earth that could threaten the dinosaurs. They would not think of breaking through themselves because they were already powerful enough. , so progress will be particularly slow.
There are still many theories about the extinction of dinosaurs
1, meteorite collision theory. According to research, an asteroid with a diameter of 7 to 10 kilometers fell on the surface of the earth 65 million years ago, causing a big explosion and throwing a large amount of dust into the atmosphere, forming a dust fog that blocked the sky and caused photosynthesis of plants. The function of was temporarily stopped, and the dinosaurs became extinct as a result. 2. The theory of climate change. 65 million years ago, the earth's climate changed suddenly and the temperature dropped significantly, causing the oxygen content of the atmosphere to drop, making it impossible for dinosaurs to survive. Some people also believe that dinosaurs are cold-blooded animals with no hair or warm-keeping organs on their bodies and cannot adapt to the drop in earth temperature until they freeze to death. 3. The theory of continental drift. Geology Research has proved that in the era when dinosaurs existed, there was only one continent on the earth, that is, Pangea. Due to changes in the earth's crust, this continent experienced major divisions and drifts during the Jurassic Period, which eventually led to changes in the environment and climate, and the dinosaurs became extinct as a result.
At the same time, there are also theories such as the struggle of species, the theory of geomagnetic changes, the theory of angiosperm poisoning, the theory of acid rain, and so on. However, there is still no precise cause of extinction.
