THE REPRODUCTIVE POTENTIAL OF WORKERS IN SLAVE-MAKING ANTS

Colonies of slave-making ants have been used repeatedly to test sex al location theory. It was suggested that workers of slave-making ants ar e more strongly selected to reproduce than workers of related, non-par asitic species, because they are incapable of manipulating sex allocat ion and the sexualization of larvae in their colonies. I show here tha t in slave-making Formicoxenini, worker ovaries on average consist of significantly more ovarioles than in non-parasitic Leptothorax species . Similarly, whereas in most Leptothorax species, workers form reprodu ctive hierarchies and lay eggs only in orphaned colonies, slave-maker workers show antagonistic interactions already in the presence of the queen and at least in some species have been observed ovipositing in q ueen-right colonies. The significance of these results is discussed.