Analysis of impulse rate and impulse frequency spectrum in the grasshopper, Omocestus viridulus, during adult development

ABSTRACT. In the grasshopper O.viridulus , two song parameters were analysed during post-larval ontogeny. The impulse rate (i.e. the rate at which the femur pegs strike the forewing vein) shows a modulation during up- and downstrokes of the hindleg. During post-larval development there is no detectable change in characteristic impulse intervals, indicating a constancy of the hindleg-stroke movement irrespective of age. The impulse frequency spectrum also shows considerable constancy during post-larval ontogeny. Apparently, the main song features, including the underlying motor pattern, are completed with the early song productions of the adult.