Why are most living things symmetrical

First of all, to correct it, the symmetry of organisms is mainly reflected in animals, and plants basically do not have such a thing, and only talk about left and right symmetry, and the front and back are generally asymmetrical.

From the perspective of animal evolution, this body shape is mainly due to the fact that animals move from floating in the water to crawling on the bottom. ......This body type is of great significance for the evolution of animals. Because where the two sides are symmetrical, the body can be clearly divided into front and back, left and right, dorsal and ventral.

The dorsal surface of the body develops the function of protection, the ventral surface develops the function of movement, and the forward end is always the first to contact the new external conditions, which promotes the nervous system and sensory organs to concentrate more and more on the front end of the body, and gradually appears the head, which makes the animal change from non-directional movement to directional movement, so that the animal's sensing is more accurate, rapid and effective, and makes its adaptation more extensive. The symmetry of the sides is not only suitable for swimming, but also for crawling. It is only by crawling in water that it is possible to evolve to crawling on land.

Therefore, symmetry on both sides is an important condition for the development of animals from aquatic to terrestrial. ”

Excerpted from the third edition of General Zoology, edited by Liu Lingyun and Zheng Guangmei.

The symmetry of the left and right of living things is the result of evolution, which makes it easier for organisms to move. For example, if a tiger's legs are long and short, it will affect its hunting, and such tigers may be eliminated naturally and will not exist forever. There are also asymmetrical creatures in the world, such as flounder.

The two eyes of this fish grow on the same side of the body, which is different from ordinary fish. This also makes the flounder have a very different lifestyle from other fish, always swimming with their bodies on the side, with their eyes facing upwards.

When observing the natural world, many people find that some things grow roughly symmetrical, such as trees, such as animals. People also follow this principle when making various items, such as a table that is symmetrical and round or square or rectangular. Mainly because people are used to it, if there is asymmetry, the table may make the space look messy.

However, there are also people who like the beauty of asymmetry and think that it is very artistic. This is still relatively related to personal aesthetics, and it cannot be demandingly consistent. Some people believe that it is precisely because of symmetry that all symmetrical creatures on the earth, including humans, can actively move in a certain direction without deviation.

Asymmetrical flounder was introduced above, but there is also a crab that is also very asymmetrical, this crab has a small pair of pincers and a very large pincer. The name of the crab is fiddler crab, and when it encourages and walks, the crab will place its large pincers horizontally in front of it, as if it were a shield. As for why fiddler crabs look like this, this is also a choice of nature.

There are still many asymmetrical creatures in the world, and interested netizens can check them on the Internet.

In fact, the creatures in nature are really very peculiar, and human beings cannot completely study the rolling judgment, and some people say that nature is more casual and will not be so particular.

Because symmetrical organisms have a higher chance of survival, they are also more reasonable from the overall structure. There are asymmetrical creatures, such as flounder.

This may be due to the axial symmetry structure in the inherited genes, which is a kind of heredity**, so there will be such a heredity as local slag. Only animals have left-right symmetry, and there is no left-right symmetry in plants, so all plants are asymmetrical.

For living beings, the advantage of symmetry is athleticism. It is precisely because of symmetry that human beings, including other symmetrical animals on the earth, can actively move in a certain direction, otherwise they can only circle in place. There are no asymmetrical ones.

Because in this way, it will be more convenient for living things to evolve; Yes, like flounder.

In fact, for us, most of today's creatures are all symmetrical all over the body, and often the body chooses a symmetrical structure, which is also because the body is more stable, and more flexible and changeable, so there are very few asymmetrical creatures in the world, which is also due to the fact that organisms have gradually improved their special body structure in the long evolution, so the symmetrical body structure can be regarded as the development trend of the evolution of organisms in nature, and it is precisely because of this that there will be no asymmetrical creatures. This is also due to a number of areas.

There are often no asymmetrical organisms in nature, and it is also because the bodies of symmetrical organisms tend to be more flexible and changeable, so they are gradually fixed body structures in the evolution of organisms.

In it, I can find that most of the creatures in nature are often symmetrical in their body structure, which is also because most of the creatures in nature have gradually perfected the stable body structure through difficult evolution, and the symmetrical body structure is more flexible and changeable, and can better meet the needs of the daily life of the organism.

Most organisms tend to have symmetrical bodies, which is also necessary for aesthetics and can maintain the balance of forces, so it is precisely because of this that most organisms have evolved into symmetrical body structures.

In it, it is found that many of these organisms are often symmetrical all over the body, which is also a sign that symmetrical design is beneficial to be able to better maintain the stability of the human body, and on the other hand, it is more beautiful and generous, so that the creatures on the earth are also symmetrical body structure. There are no asymmetrical organisms in nature, and even if these organisms appear to be asymmetrical, they actually have symmetrical structures in their bodies.

In fact, you will find that there is indeed an asymmetrical organism in nature is a very special situation, from some levels, the recent body structure is the development trend of species evolution, from some levels, the body is more beautiful and generous, and the stable structure is precisely because of this symptomatic **, it can be regarded as the root of the body structure of the organism.

In it, most of the creatures are often symmetrical because the body is more beautiful and generous, in line with the beauty of nature, on the other hand, the symmetrical body structure, shared with the body-themed activities, and can also be improved, the stability of the body.

Because the cells of living organisms will continue to evolve, and many cells with common characteristics will appear according to the process of cell secretion, so organisms are symmetrical.

Because symmetrical organisms will develop better and healthier, and symmetry has been formed in the process of development.

The main thing is to follow the laws of nature, and it will be more harmonious this way.

Answer]: Bilaterally symmetrical is the body shape of the animal that appears from the phylum Platyzoa. This type of animal is characterized by the fact that there is only one central axis of the animal's body, which can divide the body into two equal parts.

The animal body can be clearly divided into anterior and posterior, left and right, dorsal and ventral. The appearance of this body shape strengthens the functions of various parts of the animal: the dorsal surface of the body develops a protective function, and the ventral surface develops the functional function of locomotion.

It promotes the nervous system to arouse and the sense organs to concentrate more and more at the front of the body, and gradually appears the head, so that the animal changes from non-directional movement to directional movement, so that it can adapt to a wider range. Bilateralism is not only suitable for swimming, but also suitable for crawling, is the result of animals floating in the water into the bottom of the water to crawl, and the bottom crawling can evolve to land crawling, therefore, bilateral symmetry is one of the necessary conditions for animals to evolve from aquatic and mega to terrestrial.

In our daily life, we find that many things have symmetry, such as the left hand and right hand of people, and the leaves of trees, so we often think about itAll living things are symmetrical, why is that? After the research of scientists, it has been found that many organisms have symmetry, which is determined by the genes in many organisms, so when we are thinking, we must also see whether our conjecture is scientific.

All living things are symmetrical, and it is said that this is because of the need for balance, because they live on the earth and are subject to the gravity of the earth.

However, most of the symmetrical things on earth are animals, and plants generally have no symmetry.

The traits of organisms are all determined by genes, they are the result of the continuous adaptation of organisms to the environment to survive and evolve, and most organisms are symmetrical. But there are also asymmetrical ones, such as hermit crabs, conch and other creatures.

The characteristics of biological symmetry are determined by the genes in many organisms. Symmetry facilitates the coordination of organisms and helps animals maintain balance. Therefore, higher animals and plants are basically symmetrical.

3. Symmetrical organisms are actually better adapted to the regional environment, and those asymmetrical organisms do exist, and after continuous long evolution, they form a unique way of life. Among them, we found that some microorganisms do not have symmetrical body structures, and for us, such body structures are actually natural choices, in a sense, this psychological structure can also maintain body balance, and in a sense, it is also a long-term evolution, forming a unique body structure.

In fact, for us, the reason why living things are most of the time to their own bodies is because such a body is easier to maintain body balance, and it is more beautiful, and it can also help creatures survive better.

Symmetry comes from the uniformity of space, and if an organism is born asymmetrical, then it is likely that it will not be able to maintain equilibrium under the action of gravity. For example, if you have a disabled limb, you will not be able to survive in the animal kingdom, and humans must use assistive tools, otherwise your body will be unbalanced. There are still asymmetrical animals, such as the flounder, which has eyes on one side of its body; Hermit crabs are generally asymmetrical on the left and right sides, and the tail segment is often asymmetrical; Sea snails, which are generally molluscs, tend to have asymmetrical bodies, and their shells are also spiral-shaped.

There are also some shellfish that are also asymmetrical. But life on land is basically symmetrical.

Yes. Ninety-nine percent of the creatures on Earth are symmetrical, but the sunfish in the sea are not symmetrical, and the sponges in the sea are also asymmetrical.

3. There are no asymmetrical organisms in nature, and even those seemingly asymmetrical organisms actually have symmetrical distribution structure characteristics in their bodies. In fact, we will find that there is indeed an asymmetrical life in nature, of course, it is a very special phenomenon, in some ways, the recent body structure is the functional trend of species evolution, and in some ways, such a body is more beautiful and stable, and because of this, it is the root of the body structure of life.

Among them, we also found that the reason why most creatures have symmetrical bodies is also because such bodies are more beautiful and conform to the aesthetics of nature, and on the other hand, symmetrical body structures, which are used for physical activities, and can also enhance the balance of the body.