What's wiggling around underground . and underwater? Worms! They're more than just the squiggly things on a fish hook. Worms live in the earth, in the sea, in other bodies of water, and even inside insects or animals. They can be round or flat, really long or microscopic, colorful or see-through, even glowing. Learn more about how these wigglers live, what they eat . and who eats them.