Article révisé par les pairs
Résumé : According to the marking activity and to the behaviour of ants, two areas can be distinguished outside the nests of Cataglyphis cursor. One is the vicinity of the nests, near the nest entrance. Here, the ground is covered with many hindgut spots, and resident ants aggress alien ones in 50% of their encountering. The vicinity of the nests can thus be considered as being territorially marked. Elsewhere the foraging area is covered with only few hindgut spots, and resident ants are not aggressive towards alien ones. The marking of this area is species- rather than colony-specific and can be considered to be a home-range marking. It was set up progressively in about two hours in our laboratory conditions, by the first foragers crossing the area, and was regularly maintained thereafter. Experiments revealed that the hindgut may play a part in C. cursor territorial marking, and that the outside workers' Dufour gland may allow the specific home-range marking. The poison gland probably interferes with the alarm-defence system of the species. The organ content of the young workers is inefficient, or at least less efficient, than that of older nestmates. This result points out the existence of some age-related physiological changes in the workers. © 1993.