Termites

Termites live in colonies (groups) with as many as several million members.Termites, sometimes incorrectly called "white ants", are a group of social insects usually classified at the taxonomic rank of order Isoptera .As truly social animals, they are termed eusocial along with the ants and some bees and wasps. Termites mostly feed on dead plant material, generally in the form of wood, leaf litter, soil, or animal dung, and about 10% of the estimated 4,000 species are economically significant as pests that can cause serious structural damage to buildings, crops or plantation forests. Termites are major detrivores, particularly in the subtropical and tropical regions, and their recycling of wood and other plant matter is of considerable ecological importance.
A large Termite Mound in Australia:

Termites build nests to house their colonies. Nests are commonly located in larger timber or in the soil in locations such as growing trees, inside fallen trees, underground, and in above-ground mounds which they construct, commonly called "anthills" in Africa and Australia.