HUNT, R.E.: Mating behavior in leafhoppers and treehoppers: involvement of vibrational signals in male-male competition and female preference

The evolution of communication systems is strongly influenced by the types of signals used by animals and the environment though which they are transmitted. For example, acoustic signals are transmitted rapidly over great distances and the environment influences signal fidelity in predictable ways. Thus, sexual selection acting on signals and receiver mechanisms is possible and has resulted in competitive interactions among males and female preference in many insect and vertebrate taxa. In contrast, sexual selection is generally thought to be unlikely in organisms that use vibrational signals on plants because of their short range. I review recent studies of the leafhopper Graminella nigrifrons that show that sexual competition among males involves vibrational signals. Analyses of field and laboratory recordings reveal that males alternate calls (i.e. chorus) and playback experiments reveal simple rules that regulate chorus structure. It is further shown that avoiding call overlap is adaptive in that it increases a male’s mating success when involved in a scramble competition for access to a responding female. I also summarize ongoing studies of the treehopper Enchenopa binotata which suggest that females discriminate among males based on characteristics of their vibrational signals.