Characterisation of Song Structure and Introductory Notes in Owl Finches

Abstract

Before any movement is executed, the brain is thought to prepare the complex motor circuit by initializing it. A similar case of planning can be seen in the form of Introductory Notes (INs) in Zebra finches (Taeniopygia guttata) which is thought to play a motor preparatory role prior to singing. However, the study of this phenomenon in other phylogenetically related species is limited. In this thesis the song structure of Owl finches (Taeniopygia bichenovii), a phylogenetic relative of the Zebra finch, were characterised and their songs were examined using acoustic analyses and analyses of respiratory pressure recordings. From this, I found the presence of IN-like syllables in Owl finches. Additionally, I also tested if the species songs were affected after performing bilateral lesions of HVC, a key premotor nucleus in the brain involved in controlling song production in Zebra finches. Here, I found that lesioned bird songs are affected differently from Zebra finches. From all the results obtained I learned that signatures of motor preparation also exist in Owl Finches but their underlying neural circuit might differ from that of their closely related species.