2025 Theses Doctoral

Play with the changes: Innate rules for learned vocal communication in songbirds

Edwards, Jacob Aaron

Birdsong has been a muse of philosophers, artists and scientists for millennia because it is complex, intricate, and shares many features with human speech and music. Like humans and unlike most other animals, songbirds are vocal learners and communicators who use auditory skills developed in early life to shape their adult songs.

Learning confers uniqueness to each individual’s song, but the songs of individuals within a species are structurally similar, particularly in their temporal and sequential organization. The extent to which species identity drives song temporal organization, and how perceptual systems control the auditory encoding of song versus song elements are largely unknown. In this dissertation, I use comparisons of species that differ in song behavior to test hypotheses about the inborn and experiential forces that organize adult song.

Chapter 1 tests the hypothesis that song temporal organization is explained by species rather than learning by analyzing the songs of birds who were tutored, untutored, tutored by heterospecifics, or were hybrids of two species. Chapter 2 uses computational modeling techniques to test the hypothesis that the adult songs of pupils and their tutors are similar because they are the same species. Chapter 3 is an electrophysiology study that tests the hypotheses that a secondary auditory cortical region separately processes song elements versus temporal pattern, and that species-specificity for temporal pattern is a circuit-level property.

Results indicate that learned vocal communication behavior in songbirds is organized by innate rules that are, in part, determined by the species-specific encoding capacities of auditory circuits.