Ants are social insects, living in colonies that may number thousands. Ant queens lay eggs. Worker ants forage for food for the colony, care for the queen and the young, and defend the colony. Workers can be one size (monomorphic) or two or more sizes (polymorphic). Colonies may reproduce by swarming or budding. Ant nests commonly consist of underground tunnels and chambers. Some species make mounds of earth or ant hills. The queens stay in the nest and the workers bring them food. It is the workers you may see in and around the structure.