Area marking in the ant Pheidole pallidula (Myrmicinae).

The Mediterranean dimorphic ant Pheidole pallidula has a rapid, short-lasting and species-specific homerange area marking. It is performed by the minor workers, which are stimulated to mark by the major workers. The first few minors reaching a new area move on it very slowly and begin to mark it by depositing spots of their Dufour gland content. This secretion attracts other minors and a few majors, which come onto the area, then return to the nest, then come back to the area, inviting the minors to mark the area through tactile stimulations and emission of their own Dufour gland content. Contrary to the minors' Dufour gland content, the majors' one is non-attractive and does not allow marking. After about ten minutes, the ants' movements on the new area become the same as that occurring on their usual foraging area; if not walked on any further, the area loses its marking within about twenty minutes. These home-range marking characteristics may enable the ant P. pallidula to rapidly colonize new areas and keep them marked for only as long as they are useful to the society.