Date of Award


Degree Type


Degree Name

Master of Science (MS)


Bioinformatics & Computational Biology


Astragalus lentiginosus is the most taxomically diverse species in the North American flora with over 40 recognized varieties. The incredible diversity within A. lentiginosus, particularly in respect to its fruit morphology, makes it an exceptional model to study adaptation and evolution. However, it remains unknown whether fruit morphology is an adaptation and, if so, the extent to which selection or neutral evolutionary processes shape the striking diversity in this trait. In order to understand the adaptive significance of fruit morphology we must first understand the genetic structure of A. lentiginosus. Varieties of A. lentiginosus vary considerably in their range size with some encompassing broad regions and others being extremely restricted. It is unclear whether varieties represent distinct populations and thus whether distributions of varieties accurately reflect population structure. Previous studies indicate genetic structure exists within A. lentiginosus although it is unclear the extent to which different varieties represent unique genetic populations. Here I investigate genetic population structure of A. lentiginosus through neutral loci to elucidate whether phenotypic variation in A. lentiginosus may result from local adaptation or neutral processes. Additionally, I take a population genomic approach to determine the adaptive significance of fruit morphology in Astragalus. Preliminary findings indicate both genetic structure and patterns of fruit variation exist, however it is still to be determined whether these measures of variation correlate and how well this structure represents existing varieties.

Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 3.0 License.