Symmetry can give people the aesthetic feeling of perfect symmetry.
The "three elements" of beauty are simplicity, symmetry and harmony.
The symmetrical human body coincides with Huang Jinlv. From the appearance, the complex human body is so simple, while the simple human body is symmetrical everywhere. Do you think human body is beautiful?
Nature shows image symmetry everywhere, like human body, even birds, animals, fish and insects, which are mostly left-right symmetry. People's eyes, ears, hands and feet are lifelike, and the left and right halves are very symmetrical.
In addition to left-right symmetry, there are so-called "axial symmetry" and "central symmetry". The navel is called the "golden section" of the human body surface and is an important body surface symbol. Without this sign, it would be much more difficult to divide the human body into two symmetrical halves.
However, the human body is also a complex geometric figure, with points, lines, faces, triangles, circles and so on. In the details of the human body, it is not absolutely symmetrical. For example, some faces are half big and half small; Some people have big eyes and a small amount; Someone's eyebrows, one high and one low, one flat and one upturned; Some people's ears, one big and one small, one pointed and one round. Although some people look well-proportioned, careful observation can still reveal some asymmetries. Therefore, this asymmetry of the human body is everywhere and ever-changing.
In fact, this is not only the appearance from head to toe, but also from outside to inside, from static to dynamic.
Look at the head and face first.
The development of the left and right sides of the head and face is mostly inconsistent. If you take an arbitrary face photo, divide it into left and right halves according to the center line, and then restore it according to the left and right halves respectively, you can get two completely different portraits.
In the head-face asymmetry, some people are more developed on the left side, while others are more developed on the right side. Although there is little difference between the two sides, they are different after all.
Some people abroad have investigated that the external ear, eyes and nasolabial groove on the left side (that is, two deep wrinkles diagonally above the mouth on both sides) are relatively developed; On the right, there are more developed faces and nostrils.
Because the right face is often larger than the left face, the midline of a person's face tends to tilt to the left, and the tip of his nose tends to tilt to the left. Similarly, the corners of the mouth are often high on the right and low on the right. In addition, about 80% of the hair on the top of the head rotates clockwise to the right.
Look at the trunk and limbs.
The spine bends to the right in the chest; At the waist, it often bends to the left. Then, the left shoulder tends to be higher and seems wider.
According to the measurement, only 18% of human upper limbs have the same length on both sides. Most people (75%) have longer right side than left side; On the other hand, the remaining 7% is shorter on the right side than on the left.
The same is true for the measurement of bones: the diameter of the right bone is larger and thicker than that of the left bone. The lower limbs are similar to the upper limbs, and the right side is often slightly larger than the left side in terms of length, weight and volume. But the difference between the two lower limbs is not as obvious as that of the upper limbs. About 52% people have the dominant right lower limb; 15% of people have the dominant left lower limb; Both sides are equal, accounting for 33%. As for the muscles of the trunk and upper and lower limbs, they are generally developed on the right side.
The phenomenon of left-right asymmetry is also common in human internal organs, and it is more obvious.
Anatomists have long pointed out that people are eccentric. Two-thirds of the heart is on the left side of the median plane of the body, and 1/3 is on the right side; The right lung is divided into upper, middle and lower lobes, and the left lung is divided into upper and lower lobes. Right lung is wider and shorter than left lung, and right lung is heavier than left lung. The weight ratio of right lung to left lung is 10: 9 in males and 8: 7 in females. Most of the liver and gallbladder are on the right side of the body; The pancreas and spleen are mostly on the left side; When the stomach is moderately full, most of it is located on the left side of the body. The upper edge of the stomach is short, which is called gastric minor curvature, and it is depressed to the upper right; The lower edge of the stomach is long, which is called gastric curvature and protrudes to the lower left; Two kidneys, the left kidney is slender, the right kidney is short and wide, and the left kidney is heavier, slightly higher than the right kidney tip; The left and right hemispheres are not completely symmetrical. The frontal lobe is in the anterior upper part of the cerebral hemisphere, and the right side is slightly larger than the left side; The left side of the lower occipital lobe is slightly larger than the right side. In addition, the left side of the male testis is often slightly larger than the right side, and its position in the scrotum is lower, about 1 cm.
Generally speaking, the human body is symmetrical, and asymmetry is just some subtle differences, which are generally normal phenomena. The difference between the left and right sides is obvious and not obvious. So, when you find some asymmetry in yourself, or see asymmetry in others, don't make a fuss.