When New World army ants emigrate to a new nest location, the queen runs in the column accompanied by a retinue of workers. This retinue is not the same group of ants which surrounds the queen in the bivouac but is a continuously changing group. A large retinue extends 0.5–1 m in advance of the queen and 1–2 m after her. It includes up to 5 times the number of workers and soldiers, compared with an equal length of emigration column before the retinue. If the queen pauses, most of the retinue may continue without her, and a new retinue will gather around her. Disturbance of the column, even 5 m in advance of the queen, can cause her to stop and be covered instantly by a mass of ants. Such clusters and the retinue are adaptive for protecting the queen against predators or environmental hazards. It appears that the most epigaeic species have the largest retinues.