The use of communication to resolve conflicts is widespread in animals. The high degree of sociality in ants makes them ideal organisms to study communication in relation to conflicts. Ants can reduce conflicts over the reproductive division of labour by means of either aggressive or pheromonal inhibition. Whether pheromones that represent an honest signal of queen fecundity are evolutionary stable remains controversial. By comparative investigation of the mechanisms in which agression and pheromones influence the reproductive apparatus of individuals, and the origin and chemical properties of involved pheromones, we want to gain insight in the evolution of hones pheromonals signals.