How does an earthworm see or hear ?

Earthworms are found in the surface layers of moist soil which is rich in humus. They spend the day time underground in their burrows and crawl out at night in search of food.

An earthworm has no eyes but can tell when it is near the surface, for its front end is sensitive to bright light. An earthworm has no ears either but it is able to perceive vibrations in the soil and so will not venture from its burrow while a bird is hopping about overhead.

An earthworm tunnels its burrow partly by force and partly by eating its way through the soil. It feeds on decayed animals and plant remains in the soil which is swallowed. The soil is ground up by a part of its food canal known as the gizzard. The finely powdered soil is then passed out of the body forming little heaps at the entrance of its burrow. These are known as worm casts.

Earthworms are important to the farmer as their burrowing activities help to loosen the soil. This helps the roots of plants to go down easily and also allows the entry of rain water and air into the soil.