Interspecific variation of acoustic signals in Mediterranean gobies (Perciformes, Gobiidae): comparative analysis and evolutionary outlook

Sound production of 11 Mediterranean goby species, belonging to five different genera, have been comparatively analysed on the basis of the quantitative properties of the acoustic signal emitted by the male in both the reproductive and aggressive context. The results obtained showed that three groups of species can be recognized on the basis of signal similarity: the larger sized species (genus Padogobius and Gobius paganellus) producing tonal sounds, showing high values of pulse rate and low values of duration; the larger-sized species producing grunt sounds (genus Gobius and Zosterisessor) with low pulse rate and low duration; and the small-sized species producing grunt sounds (genus Pomatoschistus and Knipowitschia) with low pulse rate and high duration. The comparison between these results and those found in previous studies suggests congruence between the acoustic affinities among species and that obtained by means of morphological and genetic data. Furthermore, first hypotheses on the evolution of acoustic communication and the associated mechanisms in this fish group are suggested. (C) 2008 The Linnean Society of London.