Condition-dependent response to juvenile hormone and the evolution of cooperation in paper wasps

We tested the role of condition-dependent hormonal response in the cooperation of Polistes paper wasps. In Polistes dominulus, a species that forms cooperative foundress associations, foundresses have a condition-dependent response to juvenile hormone. Only large, high quality foundresses increase their dominance and fertility when given JH. This differential hormonal response provides a mechanism for foundresses to adaptively allocate energy based on their probability of successfully becoming the dominant queen. However, in Polistes metricus, a species that rarely forms cooperative foundress associations, condition does not influence individual response to JH. All Polistes metricus foundresses increase their dominance and fertility when treated with JH. Therefore, condition-dependent hormonal responses may co-evolve with cooperation.