Three female morphological castes in the Florida harvester ant Pogonomyrmex badius: queen (left), major worker (top), and minor worker (bottom). Archbold Biological Station, Florida, USA

Pogonomyrmex badius, the Florida harvester ant. Here, nest maintenance workers are busy removing soil they have excavated from deep in the nest. Archbold Biological Station, Florida, USA

A spiny ant worker (Polyrhachis schlueteri) forages at the edge of a South African coastal forest. St. Lucia, KZN, South Africa