A nest of Pogonomyrmex badius, the Florida harvester ant. Nests of this species are characteristically ringed with debris and small pieces of charcoal, which are thought to serve as a boundary to keep other ants away from the nest entrance. Archbold Biological Station, Florida, USA
A Pseudomyrmex spinicola acacia ant pauses outside the nest entrance. The ants cut a circular entrance hole to gain access to the inside of the hollow thorn. Chiriqui, Panama.
Deep underground, a thief ant walks through a narrow nest gallery. Armenia, Cayo District, Belize.