Why are there two thumbs in one? Couldn t it be one or three?

In our daily life, we can also find that according to the development of our human body structure, we can know that our thumb has always only had two bones, which is completely different from other fingers, which have three bones while our thumb has only two. Many people are very confused about this phenomenon, and at this time we can explain the appearance of this phenomenon according to the development of our human body and the role of the thumb.

We often use our palms and fingers in our daily lives. When we use our fingers, it's basically scratching an itch or carrying a book for us. At this time, we can find that due to the different growth directions, the thumb can not actually play any role when carrying things.

But when we press the button or play with the mobile phone, the role of the thumb is relatively very prominent, due to the special growth direction, the role of him and the other four fingers is completely different. Through comparison, we can find that the strength of the thumb is completely different from the strength of the other four fingers, and we found that the strength of the thumb is much higher than the strength of the other four fingers, so we will let the thumb press various buttons or stabilize various items in daily life.

In fact, for us, the role of the thumb is not only to carry, hold, and press the object, but also to maintain a balance of the things in our hands. If our thumb is made up of three bones at this time, then it is easy to use the same force as the other four fingers when exerting force, which makes it difficult to ensure that we use our thumb to maintain balance when holding things.

Therefore, at this time, we have explained why the thumb is composed of two bones from three perspectives: the growth of the thumb and the structure and function of the human body. In fact, in essence, we must also believe that all the structures of our human body are very meaningful and valuable.

I think it's a normal physiological phenomenon, and everyone has two thumbs, and it's also related to bone development, so I don't think it's one or three.

This is because the thumb is shorter than the other fingers, so it is two-jointed, and if it is one or three, it is not as flexible as two-section, nor is it more labor-saving than two-segment.

Because the length of the five fingers of human beings is different, in the long process of biological evolution, the thumb evolved to be relatively short, so it is two knuckles.

Our ancestors, Australopithecus, used their limbs to climb up and down trees and pick fruits. At that time, the thumb, like the other four fingers, had three knuckles. This structure makes it easy to grasp the trunk and allows the ape to move flexibly between the branches.

Later, a part of Australopithecus learned to walk upright. The main function of the upper limbs has changed from climbing to using tools. The evolution of a long period of time has given us a clear division of labor for each of our fingers.

You don't see that the thumb has only two segments, but it is the most powerful of the five fingers. If the thumb has three segments like any other finger, it will not be able to perform a large force operation. The two-segmented thumb can be combined with the other four fingers to perform a variety of hand movements, and can also work independently.

Its function accounts for 40% of the function of our entire palm! Without it, there are many tools that we wouldn't be able to use. Imagine:

How do you use scissors without a thumb?

So where did the third finger of the thumb go? In fact, if you look at the X-ray photos of the hand bones, you will find that the original third finger gradually moves towards the palm and becomes the "metacarpal bone" connected to the palm.

This structure of the thumb is one of the logical results of the evolution from ape to man, because if the thumb is composed of only one section, it is very inconvenient to grasp objects with the other four fingers; If the thumb is three-segmented, then it will appear weak and unable to perform some powerful movements.

A human hand has five fingers, which vary in length, thickness, and thickness, and each finger has its own name: thumb, index, middle, ring, and little finger. Interestingly, the index finger, middle finger, ring finger, and little finger are all divided into three segments, but the thumb has only two segments.

According to the theory of evolution, it is already known that man evolved from Australopithecus. Australopithecus lived in forests and crawled on all fours, with the thumb or big toe separated from the other four fingers (toes), and when climbing in trees, it was very useful to have three fingers or toes, while only two thumbs (toes) were of little use. Later, the apes learned to walk upright, and their upper limbs were liberated, especially after they evolved into humans, and their thumbs became very thick and powerful due to the frequent use of tools in their hands.

In the palm of the human hand, a large thenar muscle is also produced, so that the thumb can cooperate with the other four fingers on the opposite side. It is the result of this evolution that the thumb of modern humans has become the most powerful finger. The idiom is second to none and means the most outstanding, which means the thumb.

Indeed, according to scientists, almost more than half of all jobs that involve finger movement require thumb help. The thumb can work independently and in collaboration with the other four fingers, such as writing, holding chopsticks, holding a gun, etc. Why is there only two sections for such an important thumb?

Scientists believe that this structure is most suitable for it. Because if the thumb consists of only one section, it is very inconvenient to grasp objects with the other four fingers; If the thumb is three-segmented, then it will appear weak and unable to perform some powerful movements. Therefore, this structure of the thumb is one of the reasonable results of the evolution from ape to man.

<>1. According to the theory of making and making factions, it is already known that man evolved from the ancient ape. Australopithecus lived in forests and crawled on all fours, with the thumb separate from the other limbs, and only two thumbs of little use, but commanding.

2. It is the result of this evolution that the thumb of modern humans has become the most effective finger. The meaning of the idiom "second to none" is to refer to the thumb.

3. There are only two thumbs in such a heavy mountain, and scientists believe that this structure is the most suitable for it. Because if the thumb is only composed of one section, it is very inconvenient for it to cooperate with the other limbs to grasp my objects.

4. If the thumb is three-segmented, then it will appear weak and powerless, and it will not be able to perform some powerful movements. Therefore, the structure of the thumb is one of the reasonable results of the evolution from ape to man.

The white index finger, middle finger, ring finger and little finger on the human hand are all divided into three zhi

knots, only great.

Thumb DAO has only two sections, version.

This structure is best suited for the thumb of power. Because if the thumb consists of only one section, then it is the other four fingers.

It is very inconvenient to cooperate with grasping objects; If the thumb is three-segmented, then it will appear weak and incapable of some powerful movements. Australopithecus crawled on all fours, with the thumb or big toe and the other four fingers (toes).

Separated, when climbing in a tree, three fingers or toes are suitable, while two thumbs (toes) are useful.

But it's not big. After the evolution of Australopithecus into humans, they walked upright, their upper limbs were liberated, and their thumbs became very thick and powerful due to the regular use of tools. In the palm of the human hand, a ** muscle is also produced, so that the thumb can connect with it.

He has four fingers to coordinate the activity. The thumb works both independently and in tandem with the other four fingers. So, big.

This structure of the thumb is one of the reasonable results of the evolution from apes to humans.

Why is there only two thumbs in it? The rest are all three sections, so what's the point?