In the past, it was believed that snakes were deaf and could not hear anything. This belief stems from the fact that snakes do not have external ears, and they seem not to respond to noises. Current scientific studies have refuted such thoughts. The truth is that snakes do hear but not in the same way humans do. With humans, the sound wave travels through the air and hit the eardrum and causes vibrations in the tiny hair cells and the movement of small bones located in the inner ear. These vibrations translate into nerve impulses that travel to the brain.
The Ear Anatomy Of A Snake
The snakes have two ears lying behind their eyes, just like other reptiles. They only lack the external ears, which are known as ear flaps, auricles, or pinnae. They have small holes located on the sides of their heads, which are the ear openings. Inside these tiny ear-holes are fully formed inner ear structures but without eardrums or the middle ear. Unlike other animals with inner ear filled with fluids, the inner ear of a snake is filled with air. The inner ear is also connected to the jaw bone that rests on the ground as the snake slithers.
How Snakes Hear?
Besides the inner ear structure, snakes have a quadrate bone in their jaws that move in response to vibrations as they slither on the ground. For several years scientists were not sure if the snake could hear airborne vibrations. Recent research has indicated that the bone can also respond to airborne vibrations. It is believed this is possible because of spinal nerves that conduct vibrations from the skin. This type of hearing is known as somatic hearing. Just like the ears of other animals, the vibrations are sent through the bones to the inner ear and transmitted to the brain as signals where they are interpreted as sound.
What Snakes Can Hear?
Hertz (Hz) is a unit of measuring the frequency of sound or a pitch (low or high sounds). Scientists use hertz to establish if snakes can hear sounds. Some scientists have said snakes can detect low-frequency airborne vibration as well as ground vibrations that range between 50Hz and 1,000Hz. Other studies have determined that snakes have peak sensitivity that ranges between 200Hz and 300Hz, while others have put the range between 80 Hz and 160 Hz. Much is not understood about the exact range that a snake can hear. Humans with excellent hearing capabilities can hear anything within the range of 20Hz and 20,000 Hz. The range between 20Hz and 25 Hz is the lowest sound of an organ pipe, and 4,100 Hz is the highest note on a piano. Therefore, the snake can only hear low sounds.
The world is home to more than 3,000 different species of snakes, and they are found in virtually all the continents except Antarctica. According to National Geographic, the smallest snake in the world is the thread snake, which grows to about 3.9 inches long. On the other hand, the largest snake is the green anaconda. The largest fossil of a snake that has been discovered so far is the Titanoboa. The snake lived on Earth about 60 million years ago and is believed to have been about 50 feet long.