Can you really hear the sound of the sea inside a shell?

For decades, this unique phenomenon has enthusiastically attracted the attention of children and adults. looking for an explanation for this fact They often believe that these shells make the sounds of the ocean they want to return to.

Science has tried to find a more logical and fact-based theory, not wanting to get away from this beautiful metaphor. The first explanation scientists found was so plausible that it spread like wildfire. It was thought that the sounds that could be heard from inside the shell were nothing more than a strengthening of one’s own blood flow.. It made sense. Not surprisingly, when you put your head on a pillow, you can hear the blood beating inside your head. This theory was widely accepted and supported, among others, by the famous scientific popularizer Carl Sagan, who in 1973 affirmed that the melody emanating from the shell was nothing more than “the highly amplified sound of our own bloodstream.”

However, it was an easy theory to disprove. If what the conch amplifies is the sound of blood, then this sound should be variable or more intense when doing physical exercise, as sports raise blood pressure and heart rate. However, when they compared the sound heard in the shell while the person was resting and after exercising, they noticed that the shell continued to make the same sound without any change.

Even so, the scientists insisted that the one making such a sound must be an internal fluid. And what other part of the body has fluid? Definitely ear. The inner ear is constantly filled with endolymph and perilymph fluids.. They are the basic fluids that keep us in balance. It would then make sense to amplify the swaying sound of these fluids by keeping a shell on the outside of this organ.

However, another simple experiment destabilizes this theory. With each shaking of the head, the fluid in the inner ear moves. This therefore means that as we move the angle and direction of our head, the sound of the seashell should be the same. Tilting the head to one side, however, does not produce the expected mini-auditory tidal wave. The answer remained a mystery.

The answer isn’t inside, it’s outside

Then came the latest theory. What if the response is outside of the listener rather than inside? Scientists began to believe that what was heard in a seashell was air flowing through the shell, making a hissing and running sound. To confirm this, researchers they tried to listen to a seashell in a soundproof room. However, under such conditions, the conch remained completely silent.. “Before it can be heard, there must be background noise,” says Andrew King, director of the Oxford University Center for Integrative Neuroscience and chair of the Oxford Auditory Neuroscience Group.

King had found the key. LThe sounds heard through the shells and seeming to come from inside are not from inside the shell, but from its surroundings.. The shell ‘captures’ ambient noise, amplifies it and converts it into sounds that come to our ears. “The conch acts like a resonator, amplifying certain sound frequencies, making it louder without the conch being placed near the ear,” King said.

The frequency of the sound depends on the shape of the shell, but generally the sounds they receive are lower in frequency, deeper and louder. Just like those in the ocean.

However It’s not just seashells that can evoke the marine environment. In fact, almost any convex surface will do. You can try holding a teacup or bowl to your ear, or you can put your own hands together to achieve the same effect, albeit to a lesser extent. Of course, if you try this experiment in the kitchen, don’t expect to find the sound of the sea. On the contrary, you will hear the hum of the refrigerator or the pipes overflowing with water. To really hear the sound of the ocean, you will have to get close to the sea.

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