9727623 Schwartz Animal communication in nature involves detection of important signals in a noisy environment. In gray tree frog mating choruses calling males attempt to attract mates, females must discriminate among large number of competing calls and use this acoustic information to choose among competing males making this an ideal setting in which to investigate such signal discrimination in a noisy environment. The proposed research will also improve our understanding of mate assessment in nature and competition among males. Females of the gray treefrog base their choice of mate solely on acoustic criteria. In the intensely competitive environment of a chorus, males change their calls in a way that laboratory experiments suggestshould improve their attractiveness. However, we don t know how well females can assess males in the complex acoustic environment of a chorus or why certain patterns of calling are preferred. Nor are the fine details of the vocal competition that occurs among males or the relationship between these details and male condition understood. This research, using field-based tests of female choice and laboratory studies of male vocalizations, will help answer these questions in addition to addressing the general problem of signal detection in a noisy environment. Experiments will use a computer-based interactive playback system, that constitutes a new methodology for application to studies of animal communication.
