Acoustic signals are used by many kinds of animals to communicate between members of the same and opposite gender. This research focuses on how acoustic signals used for mate attraction might influence the aggregation and spacing of calling males. The treefrog system is an ideal model system because only males produce long-range sounds, which elicit phonotaxis in females and phonotaxis and vocal responses in other males. Furthermore, much knowledge is already available about the evolutionary significance of this communication and the underlying auditory mechanisms. The experiments will test the idea that calling by a small group of males (simulated by playbacks of recorded calls from speakers) can influence the onset of chorusing and the location of choruses, which are large groups of calling males. Further tests will assess the effects of signal quality on the location of aggregations of calling males within the general chorusing area. The results bear on general hypotheses about the causes and consequences of aggregated displaying, which is a common phenomenon in animals. For example, if playbacks accelerate the onset of chorusing and attractive (to females) rather than unattractive calls influence the location of aggregations within choruses, the hypothesis that males with especially attractive signals are focal points for chorus formation will be supported. If chorus onset is not influenced by playbacks and unattractive and attractive signals are equivalent in influencing location, the hypothesis that favorable locations for attracting females are focal points for chorus formation. These questions will be addressed in three different species in order to generalize the results and to learn if different environmental factors might also influence chorus formation.
Broader Impacts: This research will serve to increase knowledge of animal communication and to further the graduate education of a Hispanic student whose undergraduate education occurred in Puerto Rico. His undergraduate training lacked an opportunity for designing and conducting experiments that address broad theoretically informed research questions. Several undergraduates some of will be from under represented groups will assist the graduate student.
