Worms have no eyes or ears, but they have cells that sense light and dark, and they sense vibration. The latter is especially important for avoiding their chief predators, birds, moles and people. Worms eat organic matter such as leaves and grass, turning it into a rich compost. They pull organic matter from the surface and digest it in their burrows. In general, earthworms recycle their weight in organic waste every 2 days.
Earthworms can regenerate or replace segments to a certain extent if they are injured.
On the underside of a worm are setae , tiny bristles made of chitin, the same material in insect shells. About a third of the way toward the worm's mouth are about 6 segments that are swollen and look a little like a single segment. This is the clitellum and it means that the worm is an adult - it can mate and lay eggs. Juvenile worms don't have a clitellum. Plastic tweezers, or gloves for handling worms.