Kevin J. Roe

Systematics, evolution, & conservation

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Research

I am interested in several aspects of organismal biology including the evolutionary relationships of species of freshwater mussels, fishes and shrimps.  Since many aquatic taxa are threatened by poor land-use practices and the pollution of rivers and streams, conservation of these organisms is also a high priority for me. 

Some of my ongoing research includes:

Conservation Genetics of Freshwater Mussels

Widely recognized as one of the most endangered group of organisms in the world. I am currently working on improving our understanding of population structure of freshwater mussels using mitochondrial DNA and microsatellite data.  The two species are a study in contrasts: one, the Sheepnose, is widely distributed across musch of the U.S. but has been declining in recent years.  The other species, the Louisiana Pearlshell, is found in just two parishes in Louisiana.

Systematics and Evolution of Lampreys

The Petromyzontiformes includes about 40 species and are distributed in the Northen andSouthern hemispheres. As a group they exhibit two major life histories: parasitism vs non-parasitism.  My Co-PI Dr. Richard Mayden and several collaborators and I are investigating the evolution of these strategies as well as others using a phylogeny based on mitochondrial and nuclear DNA sequences. This research is sponsored by the National Science Foundation (DEB 89507).

Central American Freshwater Mussels

The freshwater bivalve family Unionidae is diverse, including approximately 90 genera.  Recent systematic and taxonomic studies have involved the relationship of the Unionidae to other freshwater mussel families or focused on the relationships within North American unionid genera.  Little or no research has been conducted on Central American freshwater mussels over the last century. This is unfortunate as Central America represents the southern most extent of the Unionidae in the western hemisphere and is important to unionoid systematics because it represents a geographic nexus between two distinct northern and southern hemisphere freshwater mussel clades and includes taxa found nowhere else in the world.  I am currently focusng efforts on several unionids that are endemic to Lake Nicaragua.  Understanding the taxonomic affinities of Lake Nicaraguan freshwater mussels will ultimately lead to greater understanding of the phylogenetic position, origin and evolutionary history of the Unionidae in the Western Hemisphere.

North American Atyid Shrimps

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.  North America is home to four recognized species of Atyidae: Syncaris pacifica, S. pasadenae, Palaemonias alabamae, and P. ganteri. Historically, only two named species, the Kentucky Cave Shrimp (Palaemonias ganteri) and the Alabama cave shrimp (P. alabamae) were known from the southeastern United States.  Recently however, an undescribed third species (Palaemonias sp.) of cave shrimp was discovered from two localities in Alabama.  Genetic comparison of this new population to known populations of P. alabamae revealed significant genetic differences and indicate an absence of gene flow between these populations. Similarly, genetic comparisons of specimens of Syncaris pacifica from various drainages revealed the presence of multiple mitochondrial haplotypes.

Margaritiferidae
With the help of several colleagues I have been working towards a phylogenetic analysis of the freshwater mussel family Margaritiferidae.


 

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