Date of Defense
Date of Graduation
animal behavior, acoustic communication, field sparrow, song type, simple song, song variation, sexual selection, assortative mating, reproductive isolation, dialect
The frequency, rate, and overall quality of a male’s song may indicate the singer’s physical quality, either as a threat or as a potential mate, and are used for species recognition. However, the degree to which a song must differ acoustically to communicate different information about the singer remains unclear. Analysis of male field sparrow simple song recorded in southwest Michigan revealed three structurally distinct clusters of simple song that differ in frequency characteristics. We hypothesize that songs in each cluster convey information about the singer and that receivers respond more strongly to songs more similar to their own song. To understand whether males distinguish among song clusters, we performed playback experiments on 32 males presenting simple song from the three clusters in a randomized order. We recorded behavior including number of songs, perch changes, and distance from the speaker before, during, and after song playback. We tested whether males respond differently to songs from the three clusters and whether their own song influenced response using univariate linear mixed models for each behavioral response during playback of each song cluster with male identity as a random effect. Males responded to songs from each cluster, as they changed behavior to playbacks. There was not a clear pattern of response to each individual cluster, though both males who sing narrow bandwidth and broad bandwidth songs responded similarly to each cluster, spending the most time close to the speaker during playback of higher frequency narrow bandwidth song. Also, the male’s own song appeared to influence his response, as males with narrow bandwidth songs tended to sing more during playback treatments than males with broad bandwidth songs. If trends in response increase, these clusters of song variation could have implications of assortative mating or influence on competition between males.
Foli, Eliza, "The meaning of song type: exploring behavioral responses of field sparrows to three simple song types" (2019). Honors Theses. 3109.
Honors Thesis-Open Access