GEE, JM; Cornell University: IEG and Behavioral response to conspecific and heterospecific calls in hybridizing avian species, California and Gambel’s quail

Divergence in characters that determine choice of mate, such as song, is central to the process of speciation in birds. Prior to complete speciation, preference for song may vary among individuals within a single population. Early experience with song of a particular species may contribute to this variation. This study will determine whether exposure to heterospecific song alters behavioral responsiveness and neuronal activation to heterospecific and conspecific song. In birds that learn their songs (songbirds), exposure to particular song results in both a behavioral preference for that song as well as upregulation of the immediate early gene (IEG), ZENK. In Gambel�s and California quail, which are non-songbirds with differing calls, hybridization occurs under natural conditions. I reared Gambel�s quail either with only Gambel�s quail or with both California and Gambel�s quail. I scored behavioral preference of Gambel�s quail that were presented with a choice each of possible pairings of the following acoustic stimuli: Gambel�s quail calls, California quail calls, or control tones. After rearing treatment and preference testing, I examined ZENK expression in adults that were exposed for 45 minutes to a single acoustic stimulus. Neural regions of interest include the caudal medial nidopallium (NCM), the nucleus preopticus medialis (POM) and the nucleus striae terminalis (BST). The potentially labile nature of song preference permits shifts in song preference to sweep throughout a population, which may lead to rapid evolutionary changes, from hybridization and its consequences, to speciation.