Avian coloration is the result of many physiologically distinct processes, including endogenous pigment generation, manipulation and integration of environmental colorants, and non-pigmentary (structural) color. I am interested in the evolution and conservation of plumage traits: are some types of bird coloration more plastic than others? What are the evolutionary constraints on nano-scale structural coloration and how do they compare to pigmentary color?
To explore this issue I am focusing on the Euphoniinae, a large subfamily of New World finches with striking combinations of pigmentary and structural colors. Using molecular techniques to construct a subfamily phylogeny and non-destructive techniques like Raman spectroscopy and small-angle X-ray scattering (SAXS) will allow us to understand relative rates of change across this clade.
I am also currently working to complete a study of the North American genus of true towhees: Pipilo. Within Pipilo we are exploring the validity of the Southern “white-eye” subspecies P. erythrophthalmus alleni and hybridization histories in two montane Mexican species: the collared towhee and the spotted towhee.