NESTMATE DISCRIMINATION IN THE SOCIAL WASP ROPALIDIA MARG/NATA Arun 8. Venkataraman, V.B. Swarnalatha, Padminl Nair, C. Vinutha and Raghavendra Gadagkar Centre for Ecological Sciences Indian Institute of Science Bangalore 560 012, India INTRODUCTION The genetical theory of evolution (Hamilton, 1964a,b) has revolutionized our approach to the study of interactions between animals. The prominent role ascribed by Hamilton to kinship between the partners in any interaction was rapidly appreciated and widely applied (Wilson, 1975). Although the question of whether animals have any direct means of assessing kinship amongst themselves remained untested for many years. it is now quite clear that kin recognition is a very phenomenon: The ability to discriminate kin from non kin has been reported in a marine invertebrate, subsocial arthropods, a sweat bee, honey bees, several species of ants and wasps, frogs, toads and a variety of mammals (reviews in, Fletcher and Michener, 1986; Gadagkar, 1985b; Gamboa et al., 1986; Hepper, 1986; Holldobler and Michener, 1980; Linsenmair, 1985; Page, 1986; for marine invertebrate see Grosberg and Quinn, 1986). The mechanism of kin recognition has important implications for the theory of kin selection (Gadagkar, 1985b).Particularly compelling evidence has been the strong correlation between (a) haplodiploidy in the Hymenoptera which creates asymmetries in genetic relatedness potentially favouring the evolution of sociality and (b) the observed multiple origins of eusociality in that insect order (Wilson, 1971 ). These asymmetries in genetic relatedness break down, however, if queens of social insect colonies mate multiply and produce different patrilines of daughters using sperm from different males or if more than one female lays eggs in the colony. If workers in social insect colonies preferentially aid their full-sisters, the original asymmetries in genetic relatedness can be restored. It has been argued that this is possible only if recognition templates are self-produced and recognition templates are self-based. If labels and templates are acquired or learned as a result of exposure to nestmates, it is unlikely that different genetic lines within & colony will be discriminated. Recent evidence indicates that in the tropical wasp Ropalidia marginata, queens mate multiply and use sperm from at least two to three males simultaneously (Muralidharan et al., 1986). It is theretore of considerable importance to Social Insects: An Indian Perspective (eds.) G.K. Veeresh, A.R.V. Kumar and T. Shivashankar. Published by IUSSl-lndian Chapter. Bangalore (1990). 161