Complex inter-kingdom interactions: carnivorous plants affect growth of an aquatic vertebrate

1. Coexistence of organisms in nature is more likely when phenotypic similarities of individuals are reduced. Despite the lack of similarity, distantly related taxa still compete intensely for shared resources. No larger difference between organisms that share a common prey could exist than between carnivorous plants and animals. However, few studies have considered inter-Kingdom competition among carnivorous plants and animals. 2. In order to evaluate interactions between a carnivorous plant (greater bladderwort, EUtricularia vulgaris) and a vertebrate (bluegill%, Lepomis macrochirus) on a shared prey (zooplankton), we conducted a mesocosm experiment. We deployed two levels of bladderwort presence (functional and crushed) and measured bluegill responses (survival and growth). 3. Zooplankton abundance was reduced the greatest in bluegill and functional bladderworts treatments. Bluegill survival did not differ among treatments, but growth was greatest with crushed bladderwort. Thus blueg...