Graduation Year


Graduation Month


Document Type


Degree Name

Bachelor of Arts

School or Department

Biological Sciences, Division of


Biology – Ecology and Organismal Biology

Faculty Mentor

Lila Fishman

Faculty Mentor Department

Biological Sciences, Division of


Monkeyflower, Mimulus, microgeographic adaptation, local adaptation, QTL mapping

Subject Categories

Evolution | Genetics | Genomics


Microgeographic adaptation, which occurs on a spatial scale smaller than the dispersal distance of the evolving organisms, provides a fertile context for understanding the genetic processes that shape natural variation and contribute to biological diversity. In plants, mosaics of distinct soil conditions can select for microgeographic divergence in the face of gene flow, leading to major life history transitions and novel trait evolution. Mimulus (monkeyflowers) is an emerging model genus for ecological genomics, due to tremendous diversity, experimental tractability, and a wealth of genomic resources. In Yellowstone National Park, Mimulus guttatus occurs in both geothermal soils and nearby nonthermal bogs within a few meters of each other. Thermal populations have evolved a distinct suite of traits, including both novel adaptations (e.g. dwarfism) and shifts parallel to independent transitions elsewhere in the M. guttatus species complex (e.g. annuality, self-pollination). In this experiment, I generate a quantitative trait locus (QTL) mapping population of M. guttatus to investigate the genetic basis of adaptation to geothermal soils. Using a previously-gathered replicated PoolSeq data and targeted genetic mapping, we identify a 24-gene region on linkage group 6 that is a major QTL for several traits related to thermal adaptation, such as dwarfism and annuality. This finding contributes to our understanding of the mechanisms driving adaptation to extreme habitats, as well as the genetics of parallel trait evolution.

Honors College Research Project




© Copyright 2016 Peter Breigenzer