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  • Clams of different sizes on palm

    Freshwater mussels are recognized as one of the most endangered group of organisms in the world. I am currently working on improving our understanding of phylogeography, population structure and genetic variation in freshwater mussels using a variety of molecular tools. I am also interested in understanding the role of processes such as gene flow and natural selection in maintaining genetic variation.

  • Iowa Pleistocene Snails

    The Iowa Pleistocene Snail (Discus macclintocki) is a small terrestrial snail (5–8 mm in diameter) that is included on the US list of endangered species. Discus macclintocki is endangered mainly due to its dependence on rare algific (cold-air) talus slopes adjacent to stream-beds in northeastern Iowa and northwestern Illinois.

  • Holding a clam over stream

    With the help of several colleagues I have been working towards a phylogenetic analysis of the freshwater mussel family Margaritiferidae. I have also conducted a population-level study of the federally threatened Louisiana Pearlshell (Margaritifera hembeli).

  • Shrimp next too a penny

    The family Atyidae is large and cosmopolitan in distribution, including both surface (epigean) and cave dwelling (stygobytic) forms.  The majority of atyid species are epigean and are tropical and sub-tropical in distribution.

  • Ptycho Trees

    My research in the area of phylogenetic systematics has involved using DNA sequence data to improve our understanding of the evolutionary relationships of organisms.  Phylogenetic hypotheses provide a framework to address questions as diverse as species delineation, biogeography, and character evolution.

  • Western Fanshell

    The advent of the ability to generate relatively inexpensive genomic-level data is presenting researchers the opportunity to leverage the power of genomic technologies to explore the evolutionary histories and population processes of non-model organisms.

    My lab has started generating and publishing research using reduced representation sequencing approaches such as restriction site associated DNA sequencing (RAD) to generate population genomic data for several molluscan species. To date, our results have have confirmed previous studies that used microsatellite genotyping, but have provided more robust results and have resealed population structure at a finer geographic scale.