Coping with multiple enemies - the evolution of resistance and host-parasitoid community structure

Recent work has shown that the evolution of Drosophila melanogaster resista nce to attack by the parasitoid Asobara tabida is constrained by a trade-of f with larval competitive ability. However, there are two very important qu estions that need to be answered. First, is this a general cost, or is it p arasitoid specific? Second, does a selected increase in immune response aga inst one parasitoid species result in a correlated change in resistance to other parasitoid species? The answers to both questions will influence the coevolutionary dynamics of these species, and also may have a previously un considered, yet important, influence on community structure.