The earth is a world of life rich in species. In addition to intelligent life human beings, there are more than millions of various creatures. After entering the age of science and technology, mankind has been exploring the origin of life. After Darwin’s “Theory of Evolution” was put forward, people have a direction to pursue the origin of life.
Evolution is the core of life development, so when did life on earth originate? In this regard, scientists through a large number of studies believe that life originated 3.8 billion years ago, that is, 800 million years after the birth of the earth, the initial life was just a very simple primitive life. The simple life has undergone continuous evolution and evolution, and then there is a world of life rich in species.
According to Darwin’s theory of evolution, the evolution of life is a gradual process. Since it is a gradual process, in the long 3.8 billion years, the emergence of life species should basically be average, and there should be at different stages of life. Biological fossils are right.
However, scientists have discovered through a lot of research that this is not the case. Archaeologists have discovered a large number of paleontological fossils. These biological fossils are basically concentrated 500 million years ago, and there are basically no earlier biological fossils. The period 500 million years ago was also called the Cambrian Life Explosion by scientists. About 542 million years ago to 530 million years ago, life on Earth ushered in a brilliant era of the Big Bang. Many invertebrate fossils.
Through a large number of archaeological discoveries, the correctness of the Cambrian explosion of life has been proved, so a mystery emerged: the earth has a life history of 3.8 billion years, why did the Cambrian have a life explosion? In the life years of more than 3 billion years before the Cambrian, why did there not be a large number of fossils?
This problem has caused headaches for countless scientists. Even Darwin once expressed this doubt in The Origin of Species. Many people have doubts about the origin of life on Earth and the theory of evolution. The Cambrian outbreak attracted countless paleontologists and evolutionists to find evidence to explore its cause. After a long period of research and exploration, scientists have put forward two views on this situation.
The first view is the oxygen content mutation theory. This view holds that the oxygen content of the earth’s atmosphere changed drastically 2 billion years ago, and the content began to increase substantially. Before that, the earth’s oxygen content was very low. At that time, life was anaerobic microorganisms, all living in the ocean. The lack of oxygen made the evolutionary path of life very slow, and there was no more than 1 billion time. Let life usher in a turning point.
Until 2 billion years ago, a special kind of creature appeared on the earth, it was cyanobacteria. Cyanobacteria is a very domineering creature, it reproduces very fast, and it is also the first creature on earth that can carry out photosynthesis.
We all know that the photosynthesis of plants can release oxygen, and 2 billion years ago, the carbon dioxide content of the earth’s atmosphere was very high. At that time, the earth was very hot. Until the emergence of cyanobacteria, photosynthesis continued to absorb the atmospheric air. Carbon dioxide is converted into oxygen, and the earth’s atmosphere has undergone drastic changes, and the oxygen content has greatly increased.
After a long period of time, large areas of cyanobacteria released a large amount of oxygen and also absorbed a large amount of carbon dioxide. The temperature of the earth began to drop, turning from the original heat to warm. The large amount of oxygen has prompted anaerobic organisms to gradually withdraw from the stage of history, and at the same time promoted the evolution of some archaea to become eukaryotes adapted to oxygen-rich environments.
The continuous increase of oxygen has caused a series of changes in the ecological environment of the earth, the evolution of life has accelerated, and the diversity has also changed. The rapid evolution and evolution of multicellular organisms eventually led to this explosion of life more than 500 million years ago, which opened the curtain on the evolution of life on earth to advanced organisms.
The second view is the theory of harvesting. This view holds that before the Cambrian explosion, all life on earth was very simple life. Before these simple lives, there was no obvious food chain and class nature, and there was basically no competition between different species before, and there were no so-called natural enemies. This kind of life world can be imagined to be lifeless.
However, quantitative changes can cause qualitative changes. After a large number of simple lives have been accumulated for more than 3 billion years, they finally have a qualitative change in the Cambrian period. In this qualitative change, more advanced organisms have entered the stage of history and opened up the glorious future. The evolution of life.
This view refers to the fact that the organisms on the earth have been advancing and evolving very slowly for more than 500 million years, and there is basically no major change. This is an accumulation process. When the accumulation reached a certain level, it ushered in an explosion of life more than 500 million years ago.
Which of the above two points of view is correct? No one can find an accurate answer at present. We research and explore the origin and evolution of life, mainly through the constant discovery of paleontological fossils. It is precisely because the paleontological fossils that we have discovered are basically from the Cambrian period, the Cambrian biological explosion was proposed.
In the long years before the Cambrian, the biological fossils we found were very rare, and their fossils could hardly be found in the stratum. The reasons for this situation may be very complicated. Science believes that there were no bones before the Cambrian, so it is difficult to preserve the creatures in the form of fossils. In addition, more than 500 million years ago, the geological changes were particularly severe and very It is difficult to give fossils a chance to preserve.
Bone creatures appeared in the Cambrian more than 500 million years ago, and geological activities have gradually stabilized. At this time, biological fossils are easier to preserve and easier to be discovered by us. There are still many mysteries in the Cambrian explosion of life that cannot be clarified at present, and to truly unravel these mysteries, continuous scientific progress is needed.
Only when the power of science continues to grow stronger, then we can go deeper into the earth’s crust and perhaps make unexpected and major discoveries. At the same time, through continuous research and exploration of genetic technology, it is possible for humans to create life and observe their evolutionary process in the future. Through such observational research, we may be able to truly understand the origin of life and what its evolutionary evolution looks like.