An earthworm is a tube-shaped, segmented worm found in the phylum 'Annelida'. They have a worldwide distribution and are commonly found living in soil, feeding on live and dead organic matter. An earthworm's digestive system runs through the length of its body. It conducts respiration through its skin.

It has a double transport system composed of coelomic fluid that moves within the fluid-filled coelom and a simple, closed blood circulatory system. It has a central and peripheral nervous system.

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