Humans are the new generation of "Earth Overlords" after the dinosaurs, but the two appeared 58 million years apart. This is a long process, and many stories must have happened during this period. After the dinosaurs became extinct, what happened to the earth again? What did you experience? How did humans appear?

The origin and development of mammals

Regarding the question of "how did humans appear after the extinction of the dinosaurs", we can start from the evolutionary path of mammals, because from the perspective of biological classification, humans are also mammals, and if we can delve into the development history of mammals, If you study, you will know that their rise was after the dinosaurs were extinct.

The earliest mammals can be traced back to 100 million to 85 million years ago. At that time, dinosaurs had not yet become extinct and had always occupied the dominant position on the earth. This shows that mammals and dinosaurs once coexisted on the earth.

However, because the mammals at that time were small in size and had far less survival advantages than dinosaurs, their prey and activity range were very limited. They mainly lived underground or in trees, and in most cases chose to travel at night.

Until 65 million years ago, the earth was seriously affected by the collision of planets, resulting in a sudden change in the ecological environment. In this case, the dinosaurs, which were large in size and had high energy requirements, faced an unprecedented survival crisis and even went to destruction. Mammals that were smaller in size and had smaller energy requirements survived.

Since the extinction of the dinosaurs, the mammal population has experienced explosive growth, and some new groups have appeared, such as carnivorous cats, vegetation animals, primates, etc. As time goes by, mammals continue to develop growth, and also laid the foundation for the emergence of human ancestors.

How did the first person appear?

Although humans are mammals, they are very different from other animals because humans can not only walk upright, but also use subjective thoughts to complete some unnatural behaviors. Therefore, humans have strong particularities in nature.

When idealism was prevalent, many people believed that humans were created by God. This can be fully reflected in countless mythological stories, such as Nuwa's creation of humans, Adam and Eve.

However, in modern times, the idea of materialism was proposed and recognized by more and more people. Its core idea is that living things come through evolution, and Darwin's theory of evolution also holds the same view.

Darwin believed that organisms in nature must follow the law of survival of the fittest. If they want to survive for a long time, they need to adapt to changes in the living environment and select the best genetic material. On the contrary, organisms that cannot adapt to the environment and make changes will eventually face elimination.

However, Darwin did not conduct an in-depth exploration of the nature of genetic material, but only made a theoretical analysis of the inheritance of traits.

As the level of science and technology continues to improve, humans have discovered that they have a deeper understanding of biological evolution, and have found new research methods and basis, such as fossil calculations and prehistoric biological DNA technical analysis, and finally obtained the answer to the question of the origin of human beings.

It was found that the origin and development of human beings mainly went through four stages, namely the Australopithecus stage, Homo habilis stage, Homo erectus stage and Homo sapiens stage.

Different stages of human evolution

The first stage is the Australopithecus stage. According to the calculation results of ancient ape fossils, Australopithecus came from 4.4 million to 1 million years ago. Through the analysis of fossil anatomy, it was found that Australopithecus was different from ordinary apes in that they had The ability to walk upright on two legs.

The Australopithecus fossil was first discovered by a British scholar in 1974. In addition to some child bones, there are also many adult-sized upper and lower jaw fragments and teeth inside the fossil. Its characteristics are very similar to humans, so at the beginning it was still It was included in the genus Homo and was corrected many years later.

The second stage is the Homo habilis stage. There are many Homo habilis fossils discovered so far. For example, Homo habilis fossils have appeared in Tanzania and Kenya in East Africa. The hand bones and foot bones of Homo habilis in the fossils are very similar to modern humans, and in There are also tools made from gravel present in the horizon.

According to calculations, early Homo habilis originated 1.9 million years ago. Compared with Australopithecus, they had significantly higher brain power and were able to use stones to make various required tools.

The third stage is the Homo erectus stage. They evolved from Homo habilis and are also called ape-men. They existed from 1.7 million to 200,000 years ago and have a relatively wide distribution range. They are distributed almost all over the world. , in addition to Asia, they are also found in Africa and Europe.

Its fossils were first discovered in 1891, which subsequently triggered a debate in the scientific community about the attribution of Homo erectus. Some people believed that Homo erectus belonged to humans, while others believed that they belonged to apes. Until the beginning of the last century, Peking Man fossils and stone tools The appearance of Homo erectus unified the final positioning of Homo erectus.

The fourth stage is the Homo sapiens stage, including early Homo sapiens and late Homo sapiens. Early Homo sapiens came from 200,000 to 100,000 years ago. Its fossils were discovered in a cave in Germany. The fossils contain a relatively complete human skeleton. Although the shape is very similar to modern humans, the original characteristics are also very obvious, such as a low and sloping forehead and a prominent jaw position. The overall appearance is much larger than that of Homo erectus.

Late Homo sapiens originated 40,000 years ago. Because their anatomy is almost the same as that of modern humans, they are also called anatomically modern humans. Their foreheads are further raised, their jaws have a tendency to shrink, and their physical shape More and more like modern people.

Conclusion

No matter what, the origin and evolution of human beings have gone through a long process. Although the journey to explore the truth is arduous, fortunately, we will finally get something. Through the study of ancient fossils, we know the origin and evolution process of human ancestors.

However, research on human evolution will not stop here. I believe that scientists will bring more surprises in the future with the assistance of more advanced equipment.

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