In a shallow bay near the city of Batticaloa on the eastern coast of Sri Lanka, a fascinating "underwater concert" once appeared, which aroused great interest.

Whenever night falls and the stars twinkle, you can clearly hear the melodious sound coming from the water, like playing an organ, which is fascinating.

After careful investigation by the undersea expedition team in recent years, it was discovered that the performers of this "underwater concert" are some tropical molluscs that live in the mud on the seabed. These little animals make a melodious sound every night when they digest food. When these sounds are gathered together, they become beautiful pieces of music.