Effect of Intermale Distance and Female Presence on the Nature of Chorusing by Paired Amblycorypha Parvipennis (Orthoptera: Tettigoniidae) Males

Patrick L. Galliart, Kenneth C. Shaw


Pairs of chorusing Amblycorypha parvipennis Stal males alternate the production of 3-5 s long phrases with frequent partial overlap of phrases. To determine the effect of intermale distance and the presence of a sexually receptive, sound-producing (@'ticking@') female on the nature of paired male chorusing, pairs of males were recorded, with and without the presence of a ticking female placed midway between the caged males, chorusing 3.3 m and 40 cm apart. The presence of a ticking female elicited a shortening of intervals between phrases (increase in phrase rate) and an increase in the extent of phrase overlap. In contrast, shortening the distance between males in the absence of a ticking female resulted in a lengthening of phrase interval (decrease in phrase rate) and a reduction in phrase overlap. Possible proximate and ultimate causes of these chorusing changes are discussed.

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