Actually, it's not like this. Zoologists have found in their research that snakes have different tongues and completely different functions. According to common sense, the tongue is a taste organ, and it feels the various flavors of different foods, but the snake's tongue is more like a nose, and there are no taste buds on the surface, so it can't tell the difference between sweet and sour, but it can smell the smell of the outside world.
As we know, odor is formed by the action of volatile molecules of substances. When people or animals inhale, odor molecules floating in the air will enter the nose and meet the olfactory cells on the surface of the nasal cavity. At this time, the olfactory cells will transform the stimuli they feel into specific information, which will be transmitted to the brain through the olfactory nerve, thus producing the sense of smell.
In fact, snakes often stick out their tongues, not to intimidate others, but to receive various chemicals in the air, similar to the function of the nasal cavity. When the tongue sticks out, the chemical molecules in the air attach to the wet surface of the tongue, and then the tongue retracts to a pair of places in the mouth called "nasal assistance". Nose AIDS are isolated from the outside world and cannot produce sense of smell, but when the tongue brings in foreign chemicals, it can realize sense of smell.
A snake's nasal aid consists of countless sensory cells, which convert the received chemicals into some information and send it to the central nervous system. Comprehensive analysis produces a sense of smell.
Usually, snakes constantly "sniff" the smell of the outside world by swallowing their tongues. If an animal bitten by a snake escapes, the snake can use its retractable tongue to explore and track the injured person through its sense of smell until it is captured.