Sexual differences in neural tuning and their effect on active space.

Sexual differences in receptor tuning are found in the auditory system in at least two species of anuran amphibians and are common in electric fish. Since the boundary of a communication signal's active space is defined in terms of the sensitivity of the receptors to that signal, such sexual differences might result in active-space differences between males and females. In spring peepers, the sexual difference in the auditory system clearly results in a significantly larger active space in females. Among electric fish, however, sexual differences in the spectral tuning of the electroreceptors may not always result in sexual differences in active space.