Meeting Abstract

86.5  Sunday, Jan. 6  Recent song experience alters the threshold for female mate choice LYONS, S.M.*; BEAULIEU, M.; SOCKMAN, K.W.; University of North Carolina, Chapel Hill lyonssm@live.unc.edu

The costs of mate choice can be high, and therefore females should adjust their threshold for choice according to the prevalence of high-quality males. In many songbird species, vocal signals advertise male quality. Because of a constraint of frequency bandwidth on syllable-production rate, trill performance (the capacity to produce high-bandwidth syllables at a rapid rate) is thought to provide females with information about male quality. Using Lincoln’s sparrows (Melospiza lincolnii), we manipulated the perceived availability of high-quality mates by exposing one group of females to songs with experimentally reduced trill performance and another to the same songs but with experimentally elevated trill performance. Initially, females in the high-performance group spent more time next to playback speakers than females in the low-performance group, demonstrating a preference based on trill performance previously shown for this species. This difference between groups disappeared by day six of song exposure as females habituated. We then exposed all females to a novel song with trills of intermediate performance. Females accustomed to low-performance trills spent more time near the playback speaker than females accustomed to high-performance trills. In a second round, we switched the females’ treatment assignments and consequently reversed individual females’ preferences for a new novel song of intermediate trill performance. These findings indicate that females have highly flexible song-choice criteria and adjust their standards for choosing a novel song based on the quality of songs they have most recently experienced. This would seem adaptive in species in which the prevalence of high-quality males fluctuates.