Ant Colony Structure and Behavior

Ants are among the most social creatures on earth. Individuals within a colony are divided into groups with specific labor duties that all coordinate to benefit the colony as a whole. Ant colonies often contain large numbers of individuals sometimes numbering in the hundreds of thousands to millions for some species. Their nests in and around homes and structures may be located almost anywhere—in hidden and protected areas indoors, in soil near foundations, under concrete slabs, in crawlspaces, in structural wood, in the yard or garden, in trees, or in almost any protected location on a property.

There are three types of individuals, or castes, that live within the colony:

Queens typically are the largest ants in the colony. After selecting a nest site, a queen will begin laying eggs and caring for her brood. The first workers developing from the brood assume brood care from then on leaving the queen to simply lay eggs. Ant colonies can have either single or multiple queens. The number of queens in multiple queen colonies varies by species, ranging from a few queens to almost 50 percent of the total individuals in a colony. Depending on the species, queens may live from months to years.


Males serve one purpose in the colony, and that is to mate with the queen. Males typically die soon after mating and are normally present solely during the colony's reproductive stage.

Monomorphic ant workers

Dimorphic ant workers

Polymorphic ant workers

Workers are sterile wingless females and are the backbone of the colony. They perform the necessary tasks to insure the survival and growth of the colony such as foraging for food, caring for brood, excavation or enlarging the nest. Depending on the species, workers in a colony can be of all the same size (monomorphic), two sizes (dimorphic) or more than two sizes (polymorphic). There is a division of labor among workers so that some leave the nest to forage for food while others remain in the nest to perform other necessary tasks. The greater portion of workers remain in the nest. The smaller portion of workers, which are foragers, are most often noticed by homeowners when they enter homes becoming a nuisance in their search for food.