The origin of man. . . Urgent need! ! ! ! !

Today, I'm going to tell you about The Origin of Human Beings. When it comes to the origin of human beings, what issues do you care about most? Maybe one is when the earliest people appeared on the earth. Can anyone give an answer? It's okay to just say.

student a: I think it should be between three and four million years, and it first appeared in Africa.

Expert: Three million years, in Africa, what else?

Student A: I think it was Yuanmou, the Yuanmou of China. I don't quite remember the time.

Expert: There is another mastermind.

Student: It was about four million years ago, and it should be in Africa.

expert: four million years, one million years more. All right. In fact, several students just now have some truth, that is, it depends on when to say this, and it seems that it is not quite right to say it today, because our understanding of this issue has a process, so I will start from the beginning.

in the first half of last century, what were the earliest people like at that time? It was a Javanese ape-man and a Peking ape-man, so at that time, the age of Peking ape-man was determined according to the animal fossils that accompanied him. As everyone in the biology department knows, creatures evolved, and one period was not the same as another, and it was not the same in morphology. Therefore, according to the changes in biological morphology, a timetable can be made to know what this animal was like and what animals were there, for example, 5, years ago. The animal fossils with Peking Man were set at 5, years ago, so Peking Man was 5, years ago, so the historical record of mankind at that time was only 5, years. Before that, it was even shorter, that is to say, in the 19th century, the earliest human fossils were Neanderthals in Europe, and the earliest age of Neanderthals was less than 1, years, so the earliest human historical record was 1, years.

So after Peking Man, the historical record of mankind is about 5, years, so Peking Man was the earliest man at that time, and he sat on this throne for more than 2 years. From the end of the 192s to 1959, a human skull was found in Tanzania, Africa. This is the old lady. Her name is Mary Leakey. She and her husband searched for human fossils in the wilderness valley of Tanzania for more than 2 years, and nearly 3 years. By 1959, an important skull was found, that is, the middle one. This is her and her husband together with this skull. As we all know, stone tools are made by people, but they are tools of stone. The stratum where this stone tool and this skull are located is 1.75 million years ago, as determined by the methods of radioactive isotopes of potassium and argon. Therefore, the historical record of human beings was extended by 1.75 million years, which was in 1959, so it was selected as one of the top ten news in the world. In the 196s, there was an English girl named jane goodall, a high school graduate, who came to Beijing a few years ago and now engaged in animal protection. She was very interested in studying ancient humans. When she arrived in Africa, she asked that gentleman, Louis Leakey, to give her money. She lived in the dense forest and observed the life of chimpanzees. After a long time of observation, she found that chimpanzees could make tools and put grass. After removing it, insert the straw into the ant nest, because the ants in Africa are very big, and their nests are like graves, so we call it an ant grave, and insert it into that ant grave to catch the ant and eat it, that is to say, it can change the shape of natural objects and use it for ourselves, which is the beginning of making tools. So she found such a manufacturing tool. What's the significance of this discovery? This is of great significance. Before that, what is the definition of people? It is an animal that can make tools, so we found the earliest tools, the 1.75 million-year-old tools just mentioned, so we can know that there are people at this time. The Javanese ape-man was discovered in 1891, but there has been a debate for a long time and decades. It is impossible to decide whether he is a man or an ape. Why? It is because there is no tool to discover with him that his brain is between the size of modern humans and modern apes, so he can't decide. So at that time, in 1959, according to the definition of such a person, the history of people reached 1.75 million years, because the earliest tool was 1.75 million years. So now that jane goodall has discovered that chimpanzees can also make tools, it is not feasible and appropriate to make tools as a historical symbol of the boundary between humans and apes, so people have to discuss whether to use another symbol to distinguish humans from apes. Everyone knows that apes become humans, but in what state do they become humans? If you don't reach this state, you are not a person, and this sign is more difficult to determine.

At this time, people will think that in ancient Greece, there was a Plato who once defined people. What did he say about people? It is an animal that walks on two feet and has no hair. One day, his students plucked a goose and asked the teacher, is this a person? Of course, it is not a person, so it was later called Plato's goose in the book, saying that people are Plato's geese. Therefore, this definition has been abandoned, and no one has adopted it. So up to now, jane goodall has discovered that chimpanzees can also make tools, and people, as tools-making animals, can't use this definition. Then people will think back to Plato's definition at that time, and if there is any place available, they feel that there is still some truth. Then, if we modify it, it will be walking on two feet. In addition, the body should be straight, that is, walking with two feet upright, so as to be considered as a person, as long as it can achieve this, it is considered as a person, so everyone agrees to adopt such a sign, which has another advantage. It was at that time, when stone tools were used as the dividing line between man and ape, it was a thing apart after all. You can't find a man's fossil and grab a stone tool in his hand. It's impossible, right? It's a thing apart. Now it's better to define the boundary between man and ape by using his own body structure, so it's better to change the definition of such a man and extend his historical record to more than three million years. Later, in the 197s, in Ethiopia, some fossils of Australopithecus were found, more than three million years ago, which were also determined according to the radioactive isotope potassium and argon methods. At that time, he was named Australopithecus afarensis. Because it was found in Afa, a relatively complete skeleton was dug up later, which is what you see now, accounting for 4% of the whole body skeleton. On the day of discovery, they celebrated in the camp at night, because it was such a complete skeleton three million years ago, and everyone played a record at the party, which was called "Lucy in the Sky of Diamonds", so after that, they simply called this skeleton Lucy. So when I talk about Lucy, maybe some students will know. It refers to this thing, so Lucy's discovery has extended the historical record of mankind to more than three million years.

Then, in the 197s, the old lady Mary Leakey just mentioned who discovered East Africans, her husband died in the 197s, and she took a British middle school graduate with her and found these footprints in another place in Tanzania. From the study of footprints, we can know that he walked upright on two feet, and the range between each step can be measured and calculated. You see, the size of this footprint is still relatively small compared with that of modern people's feet, so people at that time were shorter than people now. This is a restoration map, which is imaginary < P >. It is the footprint of two people walking on volcanic ash, which will be piled up later, so this lithology is different. After it becomes a fossil, it can be picked out. So at this time, human history has more than three million years, so just now.

Then in the 199s, in Ethiopia in 1994, a group of American scientists discovered some fossils, 4.4 million years ago, which was the ancestor of Australopithecus. This was 4.4 million years, so a classmate said just now that more than four million years was right at this time, and this was 1994, so the human history was extended to more than four million years. In 2, the Millennium, French scientists also found some fossils in Africa. The newspaper called Millennials, and the fossils had thigh bones, which can be studied. He was able to walk upright on two legs, then called Millennials. Later, after research, he gave a formal name, the genus was called Primitive Man, and his species name was Tugen Mountain according to the place where he found it, so we translated it as Tugen Seed, which is Primitive Man. Later, a new fossil was discovered. Last year, the newspaper named him Saheer from Chad, which was about 6 million years ago, or 6

7 million years ago. So far, the historical record of mankind has reached 6

7 million years ago, but this is about such a man who walked upright on two legs. What about making tools? The earliest tools are only 2.5 million years old, and there is no earlier one. In this way, all the fossils are in Africa, so just now, my classmates said that human beings originated in Africa, and now the general understanding is like this, but is it definitely in Africa? I'm afraid I can't make a final judgment. Why? Because it can be seen from history that where the earliest fossils were found, people tend to think that where human beings originated, the Javanese ape-man discovered in Java in 1891, the Peking ape-man discovered in 1921 and the Peking ape-man first skull discovered in 1929, so at this time, people tend to think that the cradle of human beings is in Asia, and in the 192s, At that time, anthropological theory believed that the origin of human beings was because the uplift of the Himalayas made the moist sea breeze in the Indian Ocean not blow to the north of the mountain, so the area in the north of the Himalayas became dry. At this time, the forest in that place became thinner and thinner, so the ancient apes who used to live in the forest had to go down to the ground and become people. At that time, the theory was like this, so the discovery of Peking man further confirmed this theory, so quite a few people at that time.

Just now, it was mentioned that East Africans were discovered in Africa in 1959, with fossils more than 1.7 million years ago. At this time, the wind turned to Africa, but after all, in the southwest of China, especially Yunnan, when human beings originated, that is to say, in the Miocene, its climatic and environmental conditions were suitable for apes to become human beings, so the possibility of finding human ancestors in Yunnan cannot be completely ruled out, so it is still worth looking for, but it has not been found. Therefore, with the discovery of fossils in recent years, the understanding of the origin of human beings has gradually changed.

Ok, let's introduce several stages of human evolution. The earliest ones are Chadians and hominids, followed by Australopithecus and Australopithecus, which started 4.4 million years ago and are only found in Africa at present. Australopithecus lasted until 1.4 million years ago, and then disappeared. But more than two million years ago, a new species appeared among Australopithecus, that is homo habilis, this one. Some people argue that he is divided into two parts and two species, one is called Homo sapiens and the other is called Rudolph. Then, from 1.8 million years ago, a new species called Homo erectus appeared, which lasted more than 2, years ago. At this time, another kind of people appeared on the earth, called Homo sapiens. Homo sapiens has continued until now, because we are all Homo sapiens. From his physical form, from his culture, it is more detailed. Although it is only over 2, years old, it is divided into two sections, one is called early Homo sapiens and the other is called late Homo sapiens.

So just now, the first stage of human evolution includes Chadians, hominids, apes and Australopithecus. There are many species of Australopithecus. Up to now, there are seven species. Will each of them become us in the future? That's not true. There may be only one of them, or even none of them. Our immediate ancestors have not found it yet, and it is possible.

so what does this phenomenon mean? That is to say, in the process of human evolution, its pattern is bush-like. Before that, people found a fossil, saying that it was 1, years ago, and then they found a Peking man 5, years ago. So they said that this man 5, years ago became a man 1, years ago and a man now, and then another man 4, years ago and 5, years ago became a man 4, years ago, then a man 2, years ago and then a man now. That is to say, a line is stepped, step by step. So after the discovery of so many species of Australopithecus, people changed their understanding, and realized that in the process of human evolution, it was not ladder-shaped, but bush-shaped, and it was divided into many branches. These branches went extinct at different times, and there were no descendants, and only one of them stood out, and then it became like us. Is it theoretically impossible for these branches to merge with each other? Why? Because they are different species, as we all know, different species cannot mate and produce fertile offspring, so they will not mate. Therefore, the understanding of human evolution has changed from ladder to bush.

Let me show you some specimens here. These are all specimens of Australopithecus, and this is also Australopithecus. Just now, the Australopithecus is more round. Now these two apes have a ridge on their heads, which means that the masticatory muscles are particularly large, and there is not enough room for them. They grow to the top of their heads like gorillas. This kind is called the stout type, and that kind is called the slender type just now.

This picture is imaginary. It was a picture of the life of Australopithecus at that time. This is the skull of Homo habilis. You can see that the head is bigger, which is closer to our modern people. Therefore, according to the existing fossils, human beings probably originated in Africa, and ancient apes may be in Africa, possibly in East Africa. Long-term upright walking broadened their horizons, using tools, and their brains became more and more developed, so they turned into adults. About 2.5 million years ago, human beings began to manufacture the most rudimentary tools, which is the second stage of human development.

Now let's talk about the third stage. The third stage is Homo erectus. Homo erectus has Javanese Homo erectus in Southeast Asia. There are many places in China, such as Zhoukoudian. Just now, that classmate talked about Yuanmou in Yunnan.