molecular vs morphological systematics


           mtDNA                              Morphology

Incongruence between morphological and molecular data.

Ongoing Research Projects:
I. Systematics and Taxonomy of North American Polygyrid Land Snails
II. Population genetics and ecology
III. Conservation Biology

Mollusks are like many other “unpopular” taxonomic groups in that they are largely ignored and suffer from underestimation of their species richness. One portion of my dissertation research was a systematic study of terrestrial snails in the land snail genus Praticolella. My research used the tools of modern systematics; including DNA sequencing and geometric morphometrics, combined with classical techniques, such as anatomical examination and found the current classification of this group to be deeply flawed. My project will result in major changes to the generic level classification and has resulted in the discovery of seven new species of Praticolella; five of which are highly imperiled.

Another important result of this work regards the invasive species P. griseola. Previously it was believed that there was a single invasive Praticolella species, my work found there are actually three species of Praticolella invasive in the U.S., two of which were previously unknown. These species potentially differ in their invasive capabilities, economic impact, and impact on human health through disease transmission. I am continuing to work with the U.S. Department of Agriculture tracking source populations and assessing the risk posed by these invasives.

Phyloclimatics is a new area of evolutionary biology that brings together spatial analyses and systematics. My postdoctoral research builds on my previous work on the systematic relationships in Praticolella to examine phylogenetic niche conservatism. I am using the phylogenetic relationships of snails to examine the evolution of morphology and environmental niche in replicate pairs of sister-taxa. Contrary to the expectation of niche conservatism, results so far indicate that in these snails sister-taxa have non-overlapping geographical and niche envelopes as well as distinct morphologies.

I am also building on the framework provided by my previous research and expanding this work into the entire family Polygyridae, an important North American group of land snails.