Earthworms don't have lungs or other specialized breathing organs like many animals. They breathe through their skin.

Here's how it works:

* Moist Skin: Earthworms have a thin, moist skin that allows oxygen to dissolve from the air and pass into their bloodstream.

* Blood Vessels: A network of tiny blood vessels, called capillaries, lie just beneath the skin, facilitating this gas exchange.

* Mucus: Earthworms secrete a layer of mucus on their skin, which keeps it moist and allows for easier oxygen absorption.

This means that earthworms need to stay in damp environments to be able to breathe properly!