The Fitness Consequences of Interspecific Eavesdropping Between Plants

Although many ecologists have discounted the possibility of communication between plants, recent work demonstrates that wild tobacco plants with experimentally clipped sagebrush neighbors suffer less leaf herbivory than tobacco controls with unclipped neighbors. In this report, we examine the fitness consequences of resistance induced by eavesdropping. Annual tobacco plants with clipped sagebrush neighbors produced more flowers and seed-bearing capsules than plants with unclipped neighbors although these performance measures varied considerably over the five years of the study. Tobacco plants with clipped neighbors also suffered more frost damage than controls in one year. There was no indication that eavesdropping was more beneficial to tobacco in years with high risk of herbivore damage. The potential adaptive benefits of eavesdropping remain unclear based on five years of data. However, the fact that eavesdropping had strong effects on herbivory and plant performance suggests that interactions between plant species may be richer than we previously suspected.