research

Madagascar harbors incredible biological diversity and endemicity, much of which is currently threatened or endangered. A large part of my postdoctoral research works towards a synthetic understanding of evolutionary diversification across vertebrate groups in Madagascar. With colleagues and students, I am examining species limits as well as phylogeographic and population genetic structure across a number of endemic taxa including lizards, lemurs, fruit bats, and rodents. These phylogenetically diverse datasets provide a unique opportunity to test demographically, geographically, and ecologically explicit hypotheses of evolutionary differentiation. In addition, by combining geospatial modeling and coalescent-based genetic analyses we can estimate the historical demographic parameters surrounding divergence and better evaluate phylogeographic hypotheses.

I am the lead-PI on a recently awarded two-year grant that will allow us to build upon this previous work and ask how particular landscape features influence population connectivity at hierarchical spatial scales in the Dunes Sagebrush lizard and in other, ecologically distinct, lizard species within this same community. I am working in collaboration with Dr. Lee Fitzgerald, PhD student Dan Leavitt, and others to integrate population genetic, mark-recapture, GIS, and ecological data.

The Dunes Sagebrush lizard, Sceloporus arenicolus, is endemic to the Mescalero and Monahans Sands of New Mexico and adjacent Texas. Within this region, this species is found primarily in areas that are a matrix of sand dune blowouts (open depressions) and areas dominated by shinnery oak. As part of my dissertation research, I investigated some of the current and historical factors influence genetic structure across hierarchical spatial scales.

Focal work with S. arenicolus allows us to identify how both evolutionary processes and particularly contemporary anthropogenic disturbances disrupt population connectivity. The comparative approach allows us to look in greater detail at how species attributes influence genetic and phenotypic differentiation in this heterogeneous landscape and provides important data for the conservation and management of this species.

As part of my postdoctoral research, I am also investigating the evolution of genes and gene familes within and among species of strepsirrhine primates (lemurs and lorises) as it relates to population biology and speciation. This includes a student led project examining MHC variation in two populations of mouse lemurs as well as a comparative study of chemosensory receptor evolution across multiple, phylogenetically and ecologically diverse species .

As a postdoc with Dr. Leigh Johnson at BYU, I worked on the conservation genetics and systematics of herbaceous plants, mostly those in the Phlox family, but also with the genus Cycladenia. These projects included resolving species and higher level phylogenetic relationships, detecting and characterizing introgression among closely related species, and delineating species boundaries and phylogeographic patterns of divergence in species of conservation concern.

My dissertation research quantified the loss of genetic diversity within breeding ponds of two species of desert anurans (Bufo cognatus and Scaphiopus couchii) due to 1) reproductive skew and 2) larval mortality, and examined the consequences of these local patterns for among group genetic structure. Comparing ecologically similar taxa across fine temporal scales and organizational units allowed me to link species traits, habitat characteristics, and within pond dynamics to population level patterns of genetic diversity.