Ragworms live in marine water or fresh water. Ragworms can be as long as three feet and as short as one inch. They can be brown, bright red, or bright green. They have many body segments and every segment except for the first two have little outgrowths that help them move. There head has sharp retractable jaws. They eat tiny invertebrates, mud, detritus, phytoplankton and plankton. Ragworms use their jaws to eat their food. The food passes from their mouth into the esophagus and then straight to the intestine and out the anus without going to a heart.