On parrots and pupae

A persistent challenge to understanding the development and expression of animal acoustic signals has been the reconciliation of categorical counts of signal-types in a repertoire with variation within those signal-types. This body of work looks at both categorical and continuous variation in two very different animal communication systems. This first section (Part A), is an examination of simple patterns in the complex acoustic repertoire wild Yellow-headed Amazon Parrots ( Amazona oratrix ). I document variation within and among call types using manual and automated classification, among repertoires of individuals and pairs, and of populations across the species' range. Playback of population-level and genus-level repertoire variants reveal highest response levels from same and similar repertoires. I present evidence of vocal stability of vocal units within a population across thirty-four years. Subsong of juveniles (age 3 months) contain recognizable facsimiles of population-type signals. The latter chapters (Part B) explore complex patterns within the simple acoustic system of larvae and pupae of the Imperial Blue Butterfly, Jalmenus evagoras, under controlled conditions. I further developed tools to record, detect, and compare individual sound signals to facilitate comparison of entire acoustic repertoires. Such a complete sampling of signals reveals levels of variation previously unseen in this species. Long recordings also reveal diurnal patterns of signal production. Measurements of the energetic cost of signal production (measured as respiratory production of carbon dioxide) reveal that on average, calling behavior for isolated pupae accounts for about two percent of the variance in CO 2 production, but climbs as high as nearly twenty percent when comparing periods of highest and lowest calling rates. The measurement of such costs informs wider studies of costs and benefits of adaptations associated with this species' mutualistic interactions with Iridomyrmex ants.