Most people believe that earthworms can sing. In ancient China, scholars often described the melodious and rhythmic sound of earthworms, likening it to a flute, calling it “earthworm flute”. In fact, earthworms do not have vocal cords, so they cannot make any sound, let alone sing rhythmically. The misunderstanding arises because some terrestrial insects, especially crickets, often burrow into earthworm burrows and it is they who are singing.
Earthworms also do not have ears; they could be considered deaf. Interestingly, when we tap something near an earthworm, it reacts. This is because their skin is rich in tactile cells. These tactile cells are often concentrated in one area, causing small protrusions on the skin. With many such protrusions on the ventral surface and sides of the earthworm, even a slight vibration can be detected by them.
Earthworms also do not have specialized eyes for seeing things, but they can sense light and darkness. If placed in a dark box with small holes, after a few hours, the earthworm will crawl away. This is because its body surface is covered with light-sensitive cells, especially abundant at the front end of the body and around the mouth, allowing them to discern the intensity of light. Generally, earthworms dislike light and are nocturnal animals.