HAVE you ever seen a snake-charmer playing a flute or pungi and a snake swaying its head to the tune of the pungi? It is a common scene of the small town street in India or in a movie. But can a snake really hear the sound?
Snakes do not have external ears and thus, they can’t hear like how we hear the sound. Now question is, then how do they sway their head in time with the tune.
Snakes have a hearing organ inside their head, which is connected with their jaw bones. This is called a vestigial (undeveloped or immature) organ. Snakes can detect vibration of any sound by this hearing organ. Snakes jaw bones can move up, down, left and right independently. As they crawl on the ground, they can detect the location or direction of a sound, such as tapping of feet, by the movement of their jaws.
Moreover, they have sensory nerves throughout their skin and these are connected with their spinal cord. They are known as mechanoreceptor. These nerves are highly sensitive. These nerves enable the snakes to sense the vibrations of a sound.
The vibrations of the sound pass from the skin to muscles and from muscles to the jaw bones, which are connected with the inner ears. Thus sound vibration reaches the inner ears and snakes can hear the sound. But they don’t hear in the same way we hear sounds. They may hear low-frequency sound.