DISSERTATION RESEARCH: Evolution of Ultraviolet Plumage Color

Studies on the functions and evolution of bird coloration have been a significant aspect of avian research during the past century. However, recent changes in our understanding of avian vision and the light reflectance properties of feathers call into question our traditional assessments of avian colors. Hypotheses regarding bird coloration have historically been based solely on human visual capabilities, which do not include sensitivity to ultraviolet (UV) wavelengths. Yet, birds are now known to be visually sensitivity to UV light, and behavioral evidence demonstrates that manipulation of UV levels can influence social interactions. Furthermore, UV plumage reflectance is ubiquitous across birds and color differences exist among feathers that humans cannot distinguish. Using new technology which can assess feather coloration in accordance with the visual capabilities of birds, this proposal aims to answer the following question: Do color differences exist between males and females of the same species that were previously considered identical?

The results of this research could have profound implications for studies of mate choice, plumage evolution, and avian behavior. Not only will this study greatly impact future avian research, but the broader impacts include: 1) undergraduate research opportunities, 2) development of educational exercises for undergraduate students, 3) educating K-12 teachers, and 4) public outreach through the Bell Museum of Natural History.