David Logue

PhD, Colorado State University

Supervisor: Dr. Bill Cade

I am a postdoctoral fellow in Bill Cade's laboratory in the Department of Biological Studies. Our laboratory is interested in the mechanism, adaptive function, and ontogeny of acoustic communication in animals. My research emphasizes novel experimental manipulations applied to understudied taxa, especially those from tropical latitudes.

Duetting in the black-bellied wren (Thryothorus fasciatoventris)
Pair-mates of over 200 bird species sing together, producing duet songs. Researchers have long debated whether participation in duet song is, on the one hand, an essentially cooperative behavior, or on the other hand, the result of conflict between pair-mates. According to the cooperative hypothesis, pair-mates sing together to inform potential intruders that two birds will jointly defend the territory. The conflictory hypothesis states that the contribution of the second singer in a duet mitigates the first singer's attempt to attract additional mating opportunities. Dave Gammon and I used new and established playback techniques to test for cooperative territory defense in a free-living population of duetting black-bellied wrens in The Republic of Panama¹. We found that male, but not female, wrens "cooperate" with their pair-mates by responding aggressively to opposite-sex stimuli, while both sexes responded aggressively toward same-sex stimuli. A quantitative review of the literature suggests that this is a broad pattern: compared to non-duetting species, duetting species exhibit a significantly higher ratio of inter-sexual to intra-sexual aggression during song playback experiments².

The black-bellied wren is typical of duetting species with multiple learned song-types in that pair-mates combine their song-types non-randomly to form duets. My recent work explores the behavioral mechanisms responsible for these non-random song type associations. In a series of field experiments, I played recordings from one mate and allowed the other mate to duet with the playback stimuli^3,4. Each female adhered to an individually specific, temporally stable mapping function linking the male song-types she heard to the female song-types with which she answered. I call the mapping function a "duet code." Males adhered weakly to a reversed version of their mates' duet codes.

Other projects involving the black-bellied wren include an application of Darwin's principle of antithesis to song structure in males and females, and a description of the breeding behavior of this little-known species^5,6.

Honest signaling and sexual selection in Madagascar hissing cockroaches

(Gromphadorhina portentosa)

Honest signaling theory predicts that when choosing among males, females will attend to traits that are costly to produce or are subject to performance constraints, such that the trait is an honest indicator of male quality (i.e. the male's expected contribution to the female's fitness). Similarly, when males compete with each other for access to females, honest signaling theory predicts that they will attend to costly or constrained signals that honestly indicate their rival's ability and/or motivation to fight.

Male hissing cockroaches earn their name by hissing during sexual encounters with females and agonistic encounters with other males. Body size constrains hiss structure; only large males are capable of producing low frequency hisses. Hiss frequency is therefore an honest indicator of male body size, a trait linked to female choice and fighting ability in a number of species. It is known that females are more likely to mate with larger males and male size affects male-male dominance interactions, but hiss frequency has not yet been directly linked to female preference or male assessment. Bill Cade, John Keyes, and I are using laboratory playback experiments to determine whether female Madagascar hissing cockroaches attend to hiss frequency when choosing whether or not to approach a male hiss. We are also interested in examining whether males use hiss frequency to assess potential rivals. Both of these lines of inquiry promise to add evolutionarily independent data points to an important body of animal communication theory.

Applied bioacoustics
Technological advances in recording and analysis of sound stand to benefit the field of bioacoustics, but only to the extent that bioacousticians understand and trust these new technologies. Together with Mike Baker and Dave Gammon, I study new acoustical technologies and assess their utility for working bioacousticians ^7,8,9.

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¹ Logue, D.M. & Gammon, D.E. (2004). Duet song and sex roles during territory defence in a tropical bird: the black-bellied wren, Thryothorus fasciatoventris. Animal Behaviour 68: 521-531.
² Logue, D.M. (2005). Cooperative defence in duet singing birds. Cognition, Brain, Behavior 9:497-510.
³ Logue, D.M. (2006). The duet code of the female black-bellied wren. The Condor 108:327-336.
⁴ Logue, D.M. (in revision). Animal Behaviour.
⁵ Logue, D.M., Droessler, E., Kunimoto, R., and Rendall, D. (in prep).
⁶ Bassar, S.K, Logue, D.M., & Bassar, R.D. (in review).
⁷ Baker, M. C. & Logue, D. M. (2003). Population differentiation in a complex bird sound: a comparison of three bioacoustical analysis procedures. Ethology 109: 225-244.
⁸ Logue, D.M., Gammon, D.E., & Baker, M.C. (2005). MiniDisc recorders versus audiocassette recorders: A performance comparison. Bioacoustics 15:15-33.
⁹ Baker, M.C., Logue, D.M. (in prep)

Curriculum Vitae