The effects of Azteca trigona odor production on canopy odor composition and heterospecific ant behaviors
Rachel LeAnn Wells, Christopher J. Frost , Stephen P. Yanoviak
University of Louisville, USA; University of Louisville, USA ; University of Louisville, USA
Ants are masters of chemical communication and release volatile odors to communicate with nestmates about local colony conditions. Azteca trigona, a common arboreal Neotropical ant, produces a pungent and distinctive odor when distressed. This odor often is detectable at least five meters away from large nests. The goal of this study was to 1) characterize the odor plume composition surrounding Azteca nests compared to the surrounding forest odor plumes and 2) to determine the effects of Azteca odors on heterospecific ant behaviors. We collected open-air odor samples 2cm from 40 Azteca nests and 30 control sites in Panama to characterize nest odor composition. We exposed 24 common arboreal ant species to the alarm pheromones of Azteca and to ambient air to determine the effects of Azteca odors on heterospecific ant behaviors. We found that the odor composition surrounding Azteca nests was significantly different from forest odors without Azteca, but that there was much overlap between odor compositions between nest and control sites. We also found that nine of the 24 ant species exposed to Azteca odors had a significantly greater response to Azteca than to the control treatment. Together, these results suggest that Azteca nests are regulating the production of odor signals and that when produced, Azteca odors change the behaviors of local ant species. Thus, there may exist a tradeoff for Azteca between when to produce and when to silence nest odor production and this tradeoff may ultimately affect the local canopy community structure.