The earth has been in this world for 4.5 billion years. At the beginning of the formation of the earth, there was no life. After hundreds of millions of years, microorganisms and other organic organisms continued to appear on the earth. The composition of these microorganisms is very simple. In the later evolution and development, new life was gradually bred, and the oldest ancestor of the earth was born.
What’s the basis for this statement that all living things on earth share a common ancestor with human beings?
Not long ago, we introduced a related article about “why bananas have human genes”. Many netizens had a great response after reading it. One of them @ Aidou netizens left a message and said: “if human genes are related to bananas, is it possible that humans evolved from plants?” In the theory of evolution, all life objects on the earth have a common source, that is, we human beings and other creatures will be inextricably linked, more or less “related”. In other words, we understand that human beings and plants or other creatures have a common ancestor. In the branch field of life evolution, there are differences, which makes the process of life evolution more complicated It’s not particularly clear. So the earth and all living things have a common ancestor. Is there any basis?
The picture shows geology and fossils
1. Fossils record the history of the earth and evolution
The general summary of geological structure mainly includes three aspects, one is monoclinic structure, the other is fold structure, and fault structure. Among them, fault is the most widely distributed in the crust, with various forms and types. Most fossils are found in the strata of sedimentary rocks. If we compare the whole strata to a book, then fossils are the words in the book, which have been recording the history of the earth and evolution. For example, fossils of birds and mammals appeared on the earth for the first time when the stratum age was more than 2.45 million years ago; if the stratum age was about 7 million years ago, multicellular organisms appeared on the earth for the first time; if the stratum age was about 21 million years ago, monocellular eukaryotes appeared on the earth for the first time. Generally speaking, from a large number of fossils that have been found, it has been confirmed that organisms evolved gradually from the primitive common ancestor through a long geological time, which also reveals the evolutionary order of organisms from simple to complex, from low to high.
The picture shows fossil birds
2. Anatomy is the best proof
All biological evolution has a common ancestor, which not only leaves relevant evidence in the stratum, but also leaves clues in the anatomy. For example, what are the characteristics of whale fins, cat forelimbs, bat wings and human upper limbs?
From the orthopedics of limbs, their arrangement order is basically similar. Although their shapes are very different and their functions are very different, their internal structures are the same. In other words, human beings, bats, whales and cats all share the same primitive ancestors.
The picture shows the skeleton of bat, whale, cat and human
3. Embryological theory also proves that human and all living things have a common ancestor
Embryology is an esoteric subject, which is responsible for studying the formation and development process of all animal and plant embryos. We can find some clues from the embryonic development of different animals and human beings. For example, when a woman is pregnant for three to four weeks, this period is called embryonic bud stage. The embryonic bud is 0.5-1cm long and looks like a small seahorse. It will have gill cleft and tail. This is very similar to the early development of fish embryo. With the development of embryo, human gill cleft and tail gradually disappear, while adult fish still maintain gill and tail. This is the process of vertebrate early embryonic development This evidence also proves that humans and other vertebrates share a common ancestor.
The picture shows a baby in embryonic bud stage
4. Proof of cell and molecule
If we humans evolved from primates, then we humans and climbing chimpanzees have similar genes, but there are also great differences. Cell biology and molecular biology have shown that there are many similarities between different organisms.
The picture shows a genetic comparison between humans and chimpanzees
Everything has evolved from a common ancestor – the ancient ancestor Luca
If everything in the world evolved from a common ancestor, then bacteria, fungi and so on are derived from this ancient ancestor. For this reason, many netizens will be curious: “what is this ancient ancestor of life? What does it look like? ” In fact, over the past decade, this issue has aroused heated debate among scholars. Some researchers believe that this ancient ancestor should be an element similar to minerals, which was born with the movement of the earth. Others believe that this ancient ancestor was produced with oxygen, which was a part of a certain gas. Although there are different opinions about the originator of life, scientists have finally found a reliable answer and solution through continuous efforts clue.
1. American scientists uncover the mystery of the origin of life
In the early stage of the formation of all things, there were only simple chemical substances. In the gradual evolution and development, amino acids were gradually produced, and finally the proteins necessary to create a single cell were formed. Scientists believe that the ancestor of all life on earth is Luca, which is a single cell organism with hundreds of genes that can replicate DNA alone. It has the basic components of modern organic matter, so how did Luca come into being? Most scientists believe that Luca exists deep underground, or in the cracks of igneous rocks. So far, scientists have not found conclusive evidence. Luca is a creature that hates oxygen and can survive and develop on its own. In other words, Luca doesn’t need to breathe, let alone oxygen. They can be self-sufficient in the dark, relying on carbon dioxide and other metabolism, converted into organic compounds. Surprisingly, such a small life is the beginning of a large family, and its descendants include all living things on earth.
The picture shows the evolution of Luca
2. In the process of life evolution, Luca follows the “gene”
In the early stage of evolution, Luca’s life characteristics are very simple. If genes are the common point of all cell structure life on earth, then in the stage of gene evolution, Luca changes with its changes. It is precisely because of the colorful changes of genes that the life of the earth blooms. The DNA code of every species on the earth is made up of genes. It is precisely because of genes that we lose some genetic advantages. For example, the appearance of parents depends on the offspring. If the appearance of parents is not high, with the inheritance of genes, the appearance of offspring will not be high. The direct reason why different tissues and cells of the same individual have different functions is that the proteins contained in cells are not identical, and the fundamental reason is the selective expression of genes.
With Luca as the origin, the branch fields of animals and plants appeared in the evolution of life
If we take Luca as the origin, we will lead to the evolution branch field, which is divided into two domains, one is eukaryote domain, the other is prokaryote domain, which includes bacteria domain and archaea domain. If eukaryotic cells are complex and multicellular organisms, prokaryotic cells do not contain complex organelles, but they have photosynthesis and aerobic respiration. So, why are species divided into animals and plants in the process of evolution?
There are many kinds of creatures on the earth. In the middle of the 17th century, Swedish naturalists divided the biosphere into plant kingdom and animal kingdom. Plants are immobile creatures, which are autotrophic by photosynthesis, while animals are motile and can absorb organic matter, which is heterotrophic.
The picture shows eukaryotic cells and prokaryotic cells
In a narrow sense, animals and fungi are relatively close. The primitive eukaryotic cells devour some aerobic bacteria, but they don’t rush to decompose after phagocytosis. Instead, they metabolize. The bacteria live a carefree life in the belly of eukaryotic cells. Their relationship is mutual utilization. The bacteria transform into mitochondria, and a large number of other substances are handed over to each other Given eukaryotic cells, they evolved into eukaryotes soon after they appeared, followed by the ancestors of photosynthetic organisms, fungi and multicellular organisms.
in other words:
Animals and plants belong to parallel evolution, they choose a completely different evolutionary path, human is not evolved from plants.
From different directions of evolution, photosynthesis has become the fixer of plant transformation ability. For example, Luca, the ancestor of all living things, is the foundation of the tree of life. During the development of Luca, it evolved into single cell life. Single cell life is the trunk of the tree of life. Through continuous division, the number of single cell life is increasing. In the process of single cell evolution, one single cell life engulfs another single cell life, and a branch of the tree of life appears. This branch is divided into animal kingdom and plant kingdom, and achieves all things on the earth.
The picture shows the evolutionary tree
Different from the evolution and development of animals, after the plant takes root and falls to the ground, it chooses to give up flowing survival, but takes root in a special environment. This environment needs fertile soil and sufficient water irrigation, and constantly interacts with the surrounding environment to nourish each other. The reproduction speed of plants is completely different from that of animals. Although plants don’t have nerve centers like human beings, they are sensitive and have unlimited growth roots. The growth process of plants is endless.
For example, the roots of a big tree pass through the earth and take root in the dark and deep land, while its branches pass through the celestial bodies and extend towards the starry sky, and finally develop into a towering tree. If we imagine the upper part of the human body as a tree crown facing the sun, the lower part of the human body is like a tree root pulled tightly by gravity. People and trees have completely different genes, but they have such a similar life structure. This is not a coincidence of the creation of nature, but the inevitable result that all creatures on the earth have a common ancestor.
In general, all organisms in the world are inextricably linked. So far, scientists have found the common characteristics of all complex organisms and reconstructed their evolution. Luca is our common ancestor, which reveals the most important milestone in the process of life evolution!