In connell’s classic experiment on barnacle distribution, the realized niche of the larger species b (semibalanus) is smaller than its fundamental niche. connell demonstrated that biotic interactions limited the distribution of the smaller species a (chthamalus). the control consisted of removing both barnacle species from one half of each rock. only abiotic factors such as desiccation (drying out) stress influenced the distribution of both species. connell demonstrated that biotic interactions limited the distribution of the larger species b (semibalanus).