Female Response to Computer-Simulated Male Drumming Call Variations in Pteronarcella badia (Plecoptera: Pteronarcyidae)

Abstract

Pteronarcella badia (Hagen), a western stonefly, was examined for population variation in male drumming signals and female response to computer-generated variation in male signals. Female response to a wide range of variation in number of beats (3–11) and call duration (57–154% of typical) encompassed observed variation in male signals, indicated a definitive window of recognition, and conformed to an all-or-none pattern. Male five-beat calls convey minimal information necessary for substantial female response, and longer calls, including the mode natural seven-beat calls, seem to have the minimal calls embedded in them. The pattern of variation in the second call interval suggests that extant calls have been derived from minimal five-beat calls by adding beats to the beginning, which accommodates mechanical error (failure to strike the substrate on either end of the call) and variable thermal regimes.