Erin Scully

Abstract
Zebra finches (Taeniopygia guttata) are one of the most sexually dimorphic songbirds, not only in appearance but also in vocal production; while males produce both calls and songs, the females only produce calls. This dimorphism provides a means to contrast the auditory perception of vocalizations from songbird species of varying degrees of relatedness in a dimorphic species to that of a monomorphic species, such as the black-capped chickadee (Poecile atricapillus). In this study I looked at neuronal expression after playback of acoustically similar hetero- and conspecific calls in male and female zebra finches, as a follow-up study to previous work conducted by Avey and colleagues (2014) on black-capped chickadees. An immediate early gene (IEG), ZENK, was measured in two auditory forebrain areas (caudomedial mesopallium, CMM, and caudomedial nidopallium, NCM). In black-capped chickadees, there was no significant difference in expression for calls produced by other species that were phylogenetically distant from black-capped chickadees. In this current study, I found no difference in ZENK expression in either male or female zebra finches regardless of playback conditions; however, there was a trend for less expression, in both males and females, in response to further related species, black-capped chickadee D notes and tufted titmouse calls. My results suggest that, similar to black-capped chickadees, zebra finch IEG expression in the CMM and NCM is related to acoustic similarity and not phylogenetic distance.