Research Projects

Local adaptation and reproductive isolation in yellow monkeyflowers

Mimulus guttatus and M. laciniatus (syn. Erythranthe guttatus and E. laciniata) are locally adapted to contrasting microhabitats and incompletely reproductively isolated. Mimulus guttatus occurs in moist seeps and meadows whereas M. laciniatus has adapted to a harsh granite outcrops by evolving highly lobed leaves, a self-fertilizing mating system, and early flowering.

Ultraviolet floral coloration in monkeyflowers

Mimulus guttatus and M. laciniatus both have yellow flowers with variable red spotting and ultraviolet patterning (UV; 300–400 nm wavelengths). There are at least two UV morphs present in M. guttatus and M. laciniatus which function in pollinator discrimination. There is also emerging evidence in other plant systems that UV coloration may be influenced by abiotic factors and contribute to local adaptation.

Speciation and hybridization between dragon lizards

The swift dragon (Ctenophorus modestus) and tawny dragon (C. decresii), previously the northern and southern lineages of C. decresii sensu lato respectively, differ notably in throat coloration (i.e. sexual signal). The polymorphic C. modestus has four distinct throat color morphs (orange, yellow, yellow with an orange center, and grey), whereas the monomorphic C. decresii has ultraviolet-blue throats. There is a natural narrow hybrid zone.

Population genetics of softshell turtles

Non-native species have the potential to induce large-scale ecological changes that threaten native ecosystem biodiversity, particularly on islands. I examined the phylogeography and population genetics of introduced softshell turtles (Pelodiscus sinenesis and Palea steindachneri) in the Hawaiian islands