CONFLICT-OF-INTEREST IN A MUTUALISM - DOCUMENTING THE ELUSIVE FIG WASP SEED TRADE-OFF

The generally accepted view that mutualisms represent reciprocal explo itations implies a greater or lesser degree of inherent tension betwee n the partners. This view emphasizes the importance of identifying con flicts of interest between the partners, and then attempting to quanti fy the effects of factors that influence costs and benefits to each. T he natural history of the speciose fig-fig wasp pollination mutualisms permits such measurements. However, previous attempts to document the presumed tensions, which are expected to result in a negative relatio nship between the production of viable seeds and pollinator wasp offsp ring, have met with mixed results, casting doubt on the existence of t he conflict. Here, we present hierarchical analyses of 929 fruits samp led from 30 crops representing nine species of monoecious New World fi gs. These analyses control for the confounding influences of variation in (1) pollination intensity (numbers of foundress pollinators); (2) flower number per fruit; and (3) the proportion of those flowers that develop, on seed and wasp production, both among and within crops. We thereby show that a negative relationship between the production of vi able seeds and wasps is, in fact, ubiquitous, thus documenting this un derlying tension inherent in the mutualism. We suggest that complex in teractions of variables that influence costs and benefits are likely t o be a general property of most mutualistic systems.