I am interested how the environment shapes the characteristics of organisms. In particular, I explore how the environment functions as both a generator of genetic and phenotypic variation and as a sieve selecting among and refining that variation. This interest lies at the intersection of ecology, evolution, and development (eco-evo-devo) and provides the opportunity to answer broad questions at various levels of biological organization. See below for synopses of some of my past projects.
Molecular mechanisms and evolution of phenotypic plasticity
As a postdoc at Indiana University (with Erik Ragsdale), I am using experimental evolution to explore the molecular changes that underlie an evolutionary transition from a phenotype that is predominantly under environmental control to one that is primarily under genetic control. I am also investigating replicate instances of the loss of plastictiy in various nematode lineages using comparative genomics and reverse genetics. Finally, I plan to investigate a possible role for nongenetic inheritance in mediating the evolution of plasticity in populations with little genetic (or no) genetic variation. Together, this work will help us better understand how the molecular mechanisms regulating plasticity evolve and how their changes contribute to evolutionary innovation and diversification.
For more information on my current laboratory:
Plasticity-led evolution in nature
My dissertation work at the University of North Carolina (with David Pfennig) explores how phenotypic plasticity mediates adaptive evolution and diversification. Using spadefoot toad tadpoles, I have focused on experimentally testing predictions of the 'plasticity-led' hypothesis of adaptive evolution. This work is needed to help inform recent debates on what role, if any , plasticity plays in the evolution of adaptive traits in the wild. Through a series of studies, we have shown that a novel tadpole ecomorph likely arose as an environmentally-induced developmental variant that was refined by selection into an adaptive polyphenism. We also have evidence that some populations are becoming fixed for the formerly induced morph (they are undergoing genetic assimilation). Finally, I have also used the spadefoot system to investigate the molecular and ecological drivers of morphological diversification within species.
For more information on my PhD laboratory:
For a video about spadefoot research done in the Pfennig Lab:
Pfennig spadefoot research video
Amphibian responses to anthropogenic stress
My Master's research at Western Kentucky University (with Jarrett Johnson) was a logical extension from my undergraduate research experience in that it investigated the physiological responses of organisms to environmental stressors. However, it had a more apparent applied value with respect to conservation initiatives and global change. I evaluated the interactive effects of UV-B radiation and glyphosate-based herbicide on larvae of the spotted salamander (Ambystoma maculatum). It appears that moderate UV-B radiation can be beneficial in certain contexts and that its interaction with a common herbicide may be surprising. In addition, the morphology, but not swim performance changed depending on herbicide formulation (e.g., aquatic versus terrestrial). This research may become more important as humans continue to modify the landscape and alter woodland habitats.
I received my B.S. in Zoology from Miami University in 2012. While there, I investigated (with Rick Lee) cross-tolerance between desiccation and freezing stress. My colleagues and I found that rapid, mild desiccation (~6h and ~10% body water) significantly improved freeze tolerance at the tissue and whole organism levels in the goldenrod gall fly (Eurosta solidaginis). This experience helped me appreciate the intensity and rapidity with which the environment can influence organismal phenotypes and fitness.