Many fossil evidences show that we evolved from orangutans or apes among primates. However, this statement lacks key evidence and it is difficult to get everyone's support. However, based on the study of early fossils, this key evidence may be explained. The missing link in the chain of human evolution may have been found, and perhaps the question of human origin is expected to be finally determined.
Since the Renaissance, academic circles have done a lot of research on similar issues. After entering the19th century, Darwin's theory of evolution seems to explain this problem. According to Darwin's explanation, biological evolution and natural selection are the main processes of human evolution so far.
He believes that all living things on the earth come from a common ancestor or ancestor gene pool, and the common ancestor of human beings comes from the evolution of Australopithecus. The extinction events experienced by species in the process of evolution make the whole process unclear.
Simply put, in the process of evolution, we have lost the key evidence to prove the evolution of our species. The similarity of species makes it difficult for us to distinguish the experience of this origin. Modern research shows that it is more complicated to spread genes among some distant relatives based on horizontal gene transfer.
So how powerful is this fossil to show people this missing link from the long river of time? Next, this paper will talk about the "lost" transitional fossils in human evolution from the issue of evolutionary origin, and its help for us to trace the origin.
Scientists believe that humans, like chimpanzees, have the same ancestors in the process of evolution. But in the later evolution, humans evolved a single species, the genus. It is from this period that humans began to break away from the evolutionary tree of primates such as chimpanzees.
Fossil evidence shows that humans began to differentiate from chimpanzees about 7 million years ago, but no obvious fossil specimens were found in the isolated chimpanzee fossils. This shows that there is no evidence of transitional fossils in human evolution.
Transitional fossil is a kind of biological fossil that not only retains its ancestors, but also retains its evolved biological life form. Especially when the evolved creatures are completely different from their ancestors.
Darwin believes that the fossil record itself is full of many uncertainties, and there are a lot of data that people don't know. If we want to talk about evolution in this respect, why not explain it by the lack of geological records?
Results Not long after the book Origin of Species came out, the discovery of archaeopteryx fossils proved to be an important fossil in the transition from dinosaurs to birds. In the later discovery of transitional fossils, more and more transitional fossils are enough to prove that all classes of vertebrates are related to different degrees.
Because evolution is not a single line, but there are many branches, the same species may have multiple branch changes and subspecies. But the biggest disadvantage of fossils is that not all transitional organisms will be embodied in transitional fossils, and only a very small proportion of people can find these fossils.
Why do scientists think Australopithecus is an important evolutionary evidence in the process of human evolution?
Obviously, this also comes from transitional fossils. In the evidence of Australopithecus fossils, scientists found that the fossilized eyes have obviously narrowed areas, the maximum width of the skull is low, the brain capacity is 35% of that of modern people, the mandible is thicker, the molars are larger, and the incisors and canine teeth are smaller.
All these evidences show that fossils are developing in the direction of human evolution. Most importantly, the body structure of Australopithecus fossils shows that they have the ability to walk in two groups. This shows that they have evolved for some time before this.
Anatomically, the fossilized pelvis looks like a human rather than an ape, and the position angle from the femur to the femoral joint to the knee makes them put their feet close to the middle of the body. This is the physiological characteristic of modern talents.
However, the problem comes again. Since they have evolved for some time, who were they before that? Or where did they begin to evolve? This problem has been puzzling scientists for many years. Due to the lack of key evidence, evolution has been stuck here.
Finally, at 20 13 and 1 month, a fossil of an unknown species was found in the mud 10 meter above the tuff site in Gulumaha. After careful study, scientists found that this may be the key evidence of human evolution.
The fossil can be traced back to 28,000 ~ 27,500 years ago, and the fossil sample is marked as LD 350- 1. Studies have shown that it is the left jawbone of an adult creature, and the skeleton part includes canine teeth, two premolars and molars in other parts. On the whole, this specimen belongs to the range of Australopithecus alpha species.
As mentioned above, scientists have always believed that human evolution came from Australopithecus, but due to the lack of transitional fossils, it can only be traced back to the evolutionary period here. However, the anatomical structure of this fossil specimen is very different from that of Australopithecus, and it is closer to humans.
The mental foramen is not located in the depression, but there is a joint keel on a bone line protruding from the midline of the mandible, and the mandible maintains a more or less constant depth, which is very close to human beings. If it is Australopithecus, then this position should be the deepest below the premolar, and the crown will be somewhat different.
This shows that this fossil has long been different from Australopithecus. Like other ancient humans, this jaw seems to have no obvious chin. This sharp difference in teeth, scientists believe that this split change is probably caused by dietary changes.
Similar tooth changes were also found in KNM-ER 543 1 sample found in Kenya in 20 15, and the left and right molars were obviously different from those of apes. And it can be traced back to earlier, about 30 thousand to 27 thousand years ago.
Scientists speculate that this may be the same species as the sample LD 350- 1, which can explain this transitional change of Australopithecus. But there is still a time difference between the two, about 2000 years.
However, the latest discovery of 20 19 seems to explain this deficiency. Stone tools found in northeastern Ethiopia can be traced back to 26,000 years ago, and may be the same species as LD 350- 1.
These sharp stone tools enabled them to have basic production capacity, and the sharper stone tools also proved that they could obtain better resources than Australopithecus, which was very beneficial to the changing climate at that time.
Scientists speculate that the living area of LD 350- 1 should be drier and more open than that of other fossil-found species. According to the diversity of grazing species, this area may be similar to modern African grasslands.
Does this explain everything? In the process of human evolution, have you found the final answer?
In fact, this problem is still difficult to understand. First, let's look at the great migration of apes. Since Africa, there have been two migrations. The first time was about 6.5438+0.3 million years ago, and the second time was about 70,000-50,000 years ago.
The distribution of anthropoids in the European continent was mainly 65,000 years ago, which was the main time period for the development of Homo sapiens. But as we said before, the branches of human evolution are very complicated, and to find the ultimate origin, there must be clear evidence.
Fossils alone are not enough. Stone tools found in Ethiopia and other areas can really answer some questions of LD 350- 1 to some extent. However, at present, scientists don't know whether this stone tool manufacturing and culture developed independently or passed down from the tradition of earlier Australopithecus.
At present, scientists can't find all the evidence of human origin, but in general, the whole historical change and evolution process is becoming clearer and clearer. From primates to Australopithecus, to apes, to modern Homo sapiens, the evolution of human beings is a long process, and it is impossible to fill the whole puzzle with only one or two fossils.
Humans have never stopped tracing their origins, which is of great significance to us. Through such research, people can know themselves more completely from the biological attributes and find out who they really are.