We usually say that moving the dog's tail is a sign of devotion. That's right. But dogs were not always domesticated. He lived in the forest. Even then the tail was moving. So what does it mean to move the tail? Scientists have found that the movement of a dog's tail and the variety of eye gestures are in fact a complex mechanism inherent in communication between dogs.
When a group of dogs encounters a stranger, they know from the position of the tail who is the leader among them. For example, if the tail is raised in the face of threats, it means that he is the leader of the party.
And the one whose tail is at the bottom should be assumed to be signaling obedience to others. What we call 'tail wagging' may have come from here.
The dog's emotions are usually expressed through the movement of the tail. It is often seen as an expression of excitement. Such a sign becomes especially meaningful among wolves of the dog breed. When two wolves fight, they try to understand each other's pulse rate, blood pressure, etc. They monitor each other's eye movements to measure these indirectly.
If the eyeball is dilated, it means he is scared. On the other hand, if the eyeball becomes smaller and has different gestures, then it must be understood that he is quite mad, and that is a matter of concern. Of course, in the case of domestic dogs, not so much is understood. Because, while living with people, their original attitude has changed a lot. Now, even if you say tutu tutu, the tail moves, again, even if you warn, the tail moves.