The Determinants of Dominance in a Primitively Eusocial Wasp

In many species of primitively eusocial wasps the position of an animal in the dominance hierarchy determines its role in the colony. Polistes gallicus, in which dominance hierarchies play an important role in social organisation, is the only species where an attempt has been made to study the determinants of dominance (1). Although an animal's position in the dominance hierarchy has been postulated to be less important in Ropalidia marginata (2), dominance hierarchies do exist and dominant-subordinate interactions are quite common (3). It may hence be of interest to study the determinants of dominance in this species. We have therefore begun to study the effects of body size, age, social experience and other factors in making an animal dominant or subordinate. We have maintained pairs of female R.marginata in laboratory cages and made behavioural observations to identify the dominant member and the egg-layer of each pair.