Gerlinde Höbel
Department of Biological Sciences, UW-Milwaukee, hoebel@uwm.edu
Signal production and reception often encompass various modalities of communication. For example, a calling frog cannot but produce a visual component as it inflates and deflates its vocal sac to emit an acoustic signal. A frog calling in a pond also creates water surface waves, and calling on a branch he creates vibrational signals. Thus, a simple “acoustic signal” actually encompasses three modalities (acoustic, visual and surface wave/vibrational). An increasing number of studies show that multi-modal signals are common and that mate choice is often based on multiple signal modalities, yet we know relatively little about the evolution of multimodal signaling. To better understand the evolution of multi-modal signals in frogs, we made detailed descriptions of visual (color, size) and vibrational portions of the signals of gray treefrog males. We also conducted playback experiments with female gray treefrogs to evaluate whether they are attracted to visual (video of calling male) signal components, and started conducting preliminary trials testing whether females respond to vibrational signal components. Funded by the Research Growth Initiative, UWM.