Where did humans first appear in the world?

"The origin of mankind" has two meanings. One is the origin of mankind, and the other is the origin of modern people.

First, the origin of mankind

1960, British anthropologist Alister Hardy proposed that human ancestors did not live on land, but lived in the ocean during the blank period of fossils. In other words, in the history of human evolution, there are millions of years of aquatic sea apes. Hardy pointed out: geological history shows that 8-4 million years ago, large areas in eastern and northern Africa were submerged by seawater, forcing some ancient apes to live in the sea and evolved into sea apes. Millions of years later, the sea receded, and the sea apes who adapted to life in the water returned to land. They are the ancestors of mankind. This is the shocking "sea ape theory".

The "sea ape theory" points out that many physiological characteristics of human beings are not found in other terrestrial primates, but exist in aquatic mammals such as seals and dolphins.

The evidence is:

(1) All primates have thick fur on their bodies. Only humans, like aquatic animals, have bare and smooth skin and no body hair.

(2) Primates have no subcutaneous fat, while humans have subcutaneous fat, which is obviously different from other primates and similar to aquatic animals.

(3) The physiological phenomenon of human lacrimal gland secreting tears and discharging salt is also a unique syndrome of aquatic animals. This is unique among primates.

(4) Humans have physiological phenomena such as sexual behavior and sweating, but primates do not, which are similar to aquatic organisms.

(5) The physiological mechanism of controlling salt balance is very different from that of terrestrial mammals, but it is very similar to that of marine animals.

(6) When people dive, there will be a phenomenon called "diving reaction" in the body: muscle contraction, decreased arterial blood flow, apnea and slow heartbeat. At this time, oxygen-enriched blood is no longer imported into skin tissues, bones and muscles and other organs, but all concentrated in the brain and heart, the most important center of the body to maintain life, so that its cells will not die in a few minutes. This phenomenon is very similar to the diving reaction of aquatic animals such as seals.

(7) Women have no pain in giving birth in water, while babies like water and have the instinct to swim, which shows that the relationship between human beings and water is unusual.

The sea ape theory has been accepted by more and more people, but some scientists have put forward different views:

(1) During the four million years in the ocean, Australopithecus has obtained some special certificates suitable for marine life in water. After returning to land, in order to adapt to life on land, we have to lose these special proofs that are suitable for living in seawater but not on land. For example, human beings can't accurately control the salt they need in their bodies, and why they didn't lose it during the evolution of returning to the mainland for millions of years.

(2) Fossils of 4 million years ago lack annual rings, and the "sea ape theory" still has no good explanation. Are there no fossils to be found living in the ocean? Haven't we found many fossils of marine life now?

(3) According to the conclusion of molecular anthropology research, the time when humans and apes began to differentiate was 5-4 million years ago, which does not support the "sea ape theory" at all.

As a result, other scientists put forward the theory of "the combination of land and sea ancestors" of human origin. That is, human beings have two ancestors, one is an ancient ape and the other is a marine creature. They believe that the reasonable explanation for this fossil gap of 4 million years ago is the genetic recombination between ancient apes and marine life. Australopithecus was born 4 million years ago, and the time required to combine and produce new species is very short, so short that it can be ignored relative to geological time, and even ten to several generations can form new species, so it can be said that there are no transitional fossils. This can not only explain the blank of fossils, but also explain why humans have some characteristics of marine life. As for what kind of marine life it is, there is a full explanation of life from time to time.

Recently, Mareuse, a scientist of the North Atlantic Treaty Organization, put forward a new view that human ancestors were aliens.

Men believe that some aliens came to the earth about 650,000 years ago. They have a high degree of wisdom and scientific knowledge and find that the earth environment is very suitable for their lives, but they can't bear gravity. So these aliens had to give up life on earth and decided to create a new race suitable for life on earth, and at the same time they could continue on earth. They chose the energetic and clever female ape-man on the earth as the object and could not get them pregnant. This gave birth to our ancestors.

The views of men really shocked the world. The evidence he cited was his research on a 50,000-year-old skull discovered in San Diego not long ago. He believes that the human intelligence represented by that skull has far exceeded thousands of times that of human beings today. It is speculated that "he" is one of the aliens who came to the earth in ancient times. He also pointed out that another evidence may be the combination of aliens and earth apes, that is, the giant patterns known on the cliffs at the top of the Andes. The man said that it was probably a true description of the combination of aliens and earth apes.

If people on earth really originated from aliens, how can we explain the ancient human fossils discovered 300,000 years ago, 400,000 years ago or even1-2 million years ago?

Whether it is "sea ape theory", "combination of land and sea ancestors" or "alien theory", it is strongly challenging the traditional evolution theory of "from ape to man". However, there is still not enough evidence to form a recognized scientific conclusion. With the development of science and the deepening of research, the human mind will use wisdom to solve its own mysteries.

Second, the origin of modern people.

There are two theories about the origin of modern people: one is the "single-region origin theory", which holds that modern people were formed when early Homo sapiens "invaded" the whole world in a certain region, which used to be considered as West Asia, but has become Southern Africa in recent years; The other is the "multi-regional origin theory", which holds that modern people in Asia, Africa and Europe all evolved from local early homo sapiens and even apes.

1967, Allen Wilson and saric * * *, professors of biochemistry and molecular biology at the University of California, Berkeley, put forward the molecular clock hypothesis. In this way, the time of separation between the genus Homo and the genus Chimpanzee was 5 million years ago (at that time, the age based on fossil evidence was14 million years ago). The research team selected women whose ancestors came from Africa, Europe, the Middle East and Asia, and indigenous women from New Guinea, Australia *** 147. According to the placenta when they gave birth to a baby, they found different types of mitochondrial DNA, some of which were close to each other, while others were completely different.

Based on this, they made a "system tree" to express their kinship. As a result, this "tree" came from a single ancestor, and then it quickly split into two branches. The mitochondrial DNA of one branch was from an individual of an African ancestor; The other is an ancestor from Africa, Asia, Australia, Caucasus and Papua New Guinea. The simplest explanation for this situation is that their ancestors came from Africa. According to the known mutation rate of mitochondrial DNA, its age is estimated to be10.4-290,000 years ago, with an average of 200,000 years.

At the beginning of 1987, Kahn Si Tong King, Wilson and others proposed to trace the mitochondrial DNA of all babies forward, and finally traced it back to a woman who lived in Africa about 200,000 years ago (140,000-290,000 years ago), which is the ancestor of people all over the world today. About130,000 years ago (90,000-180,000 years ago), a group of her descendants left their hometown in Africa, scattered around the world, replaced the local aborigines, and finally settled all over the world and evolved into modern different races. So some people call this theory "Eve Theory".

How long is the history of mankind? With the discovery of new ape fossils and human fossils, people's understanding of this problem is constantly developing and changing.

/kloc-Before the first half of the 0/9th century, the saying that "God created man" was still popular in Europe. Few people thought that human history would last for thousands of years.

The object of studying human origin and evolution is human fossils. It is difficult to find out when modern Homo sapiens first discovered it. It was not until the second half of19th century (1868) that a complete Kroma farmer's skull fossil was discovered in France that it was gradually recognized by the academic circles. In this way, in the late19th century, human history was pushed from thousands of years ago to tens of thousands of years ago.

1856, the skull fossils of early Homo sapiens Neanderthals were first discovered in the Neanderthal Valley near Dover, Germany, which caused controversy for nearly half a century. It was not until the end of 19 and the beginning of the 20th century that Neanderthals' position in the human evolution system was determined, which pushed human history forward for 120,000 years.

1890 found a small mandible in Java (then part of dutch east indies), 189 1 found a skull, 1892 found a thigh bone. After research, it was named "Homo erectus", considered as the ancestor of modern people, which pushed the history of human beings forward for hundreds of thousands of years or even12 million years.

1924, the skull fossil of Australopithecus Australopithecus was first discovered in Dunn, South Africa. It is the skull of a 6-year-old child with small canine teeth and a large occipital hole in the front of the skull base, indicating that it can walk upright with both feet. In this way, the history of mankind has been advanced to two or three million years ago.

According to the existing data of fossils and molecular anthropology, the time of human origin is estimated to be around 7 million years ago, while the earliest age of Australopithecus is 4.4 million years ago, and there is still a huge gap to be discovered in the future.

Darwin pointed out as early as 187 1 that Africa is the birthplace of mankind. His reason is that the closest animal relatives of mankind, gorillas and chimpanzees, now live in Africa. Darwin's view is despised by people, who think that such noble human beings can only originate in Europe or Asia.

Heickell, a German embryologist and evolutionist, was the first person to propose that human beings originated in Asia. He wrote in the late19th century that Asian apes (gibbons and orangutans) are more similar to humans than African apes, from which he speculated that Southeast Asia was the birthplace of human beings. His "Asian human origin theory" was most widely accepted by people in the next half century.

Osborne, director of the American Museum of Natural History in new york, believes that Asia is located in the center of other continents and the origin of various mammals, with detailed records of climate change, especially the rise of the Himalayas in the southern part of the Central Asian Plateau, which will lead to the drought period in Central Asia. This environmental change forced higher primates to adapt to the new environment, which led to the origin of human beings.

From 1927, a systematic excavation was carried out in Zhoukoudian, China, and a tooth fossil was found. After research by Canadian Blake (Chinese name Budasheng), he was named "China Ape". At the end of 1929, Pei Wenzhong was responsible for the excavation and found a complete skull as evidence that human beings originated in Central Asia.

However, since 1924, the fossils of Australopithecus were first found in Dunn, South Africa, and later many fossils of Australopithecus were also found in several other places in South Africa and many places in East Africa. Their morphology is far more primitive than that of Homo erectus, and their age is far earlier than that of Homo erectus, thus establishing the argument that human beings originated in Africa.

In a word, the origin of mankind is an event involving all parts of the world and a long historical process. In order to avoid misleading readers, don't confuse the concepts of whole and part, and don't make a conclusive judgment based on a certain excavation result in a country or a region.