Mays Lab Spring 2017
Marshall University, Department of Biological Sciences
Mays lab members
Front row (left to right): Alyssa Lycans (undergraduate), Kramer Kaplan (graduate), Haley King (graduate)
Back row (left to right): Joe Hageman (undergraduate), Justin Perdue (undergraduate), Herman L. Mays Jr (PI), Alex Murray (graduate), Jeff White (graduate)
University of South Florida
Stingrays are cartilaginous fishes that are closely related to sharks and skates. When people think of stingrays, they imagine marine species such as cownose rays, southern stingrays, and eagle rays, but there are whole taxonomic families of stingrays that are completely confined to freshwater. Freshwater stingrays can be found in river systems throughout South America and Southeast Asia, and are among the largest freshwater fish in the world. Kramer's research involves two species of South American stingrays, the Big Tooth River Stingray (Potamotrygon henlei) and the Xingu River Stingray (Potamotrygon leopoldi). These species are considered endemic to separate tributaries of the Amazon River in Brazil, as well as being popular in public aquaria. Despite their popularity, there isn't much information available on these two species. An issue is that South American freshwater stingrays are morphologically similar and have similar color patterns, which creates confusion in species identification and overall diversity. This confusion is why genetic research is important, as it can determine differences in base pair arrangements that would allow us to distinguish one species from another. Mitochondrial DNA is being analyzed with these stingrays because the genomes are smaller and more conserved than nuclear DNA. This is because mitochondria are maternally inherited and have less variability, which makes a strong foundation for seeing differences between species. The goal of this project is to sequence and represent the entire mitochondrial genomes for these two species of freshwater stingrays so the information can be used in the future for breeding programs in zoos and aquariums, but also for studying the phylogenetics for a group of fishes that is poorly understood.
My research interests include evolutionary biology, biogeography, ecology and conservation biology; particularly in amphibians. For my thesis, I am working on a comparative phylogeography of plethodontid salamanders of the central Appalachians, assessing the role of a river as a geographic barrier. The New/Kanawha River acts as a range limit for some species and as an intergradation zones for other species. The goals of this study are to construct phylogeographies among populations, estimate gene flow, and assess the role that developmental mode and degree of terrestrial tendencies have had on the evolutionary history of species with respect to a past and present river system. I am using 7 species of salamanders with ranges spanning the river to better understand the role this river plays as a geographic barrier reducing geneflow (Aneides aeneus, Desmognathus ochrophaeus, Eurycea cirrigera, Gyrinophilus porphyriticus, Plethodon cinereus, Plethodon glutinosus and Plethodon wehrlei). I am combining ecological niche modeling with molecular approaches to test hypothesis regrading constraints on species distributions. As plethodontid salamanders often have narrow niches and limited ranges, I am interested in the role that climate change may play in the future of these species. I aim to be able to contribute to taxonomic clarity for understudied species, understand rivers role as barriers for salamanders and highlight which species will be most susceptible to declines due to climate change in the future. Follow me on Instagram.
Middle Tennessee State University
My research interests include avian evolution, genetics, and ecology as well as wetland and marine ecosystems – particularly in the Southern Hemisphere. My current research focuses on the foraging niche plasticity of Fiordland Crested Penguins (Eudyptes pachyrhynchus). Worldwide penguin populations are declining, due in part to rapidly changing oceanic conditions from global climate change. Although they live across a wider variety of marine ecosystems than most other penguins, the Fiordland Crested Penguin is no exception. This species nests in the temperate rainforests of the south west coast of New Zealand’s South Island but where they forage and what prey species are preferred is poorly understood. I am employing a minimally invasive technique, stable isotopic analysis, to open a window into the elusive marine foraging ecology of this enigmatic species. Through this research, a clearer understanding of Fiordland Crested Penguin’s feeding niche will be revealed which can be used to help predict how this species will respond to their changing marine environment. Follow me on Twitter and Instagram.
I’m working on a species delimitation of the Japanese White-eye (Zosterops japonicus). This species of bird is found throughout East Asia, inhabiting both the continental mainland and islands in the region. As of now there are 9 described subspecies, however, despite its abundance little work has been done on this species. Because of the lack of genetic data on this species, I am using a molecular phylogenetic approach to better describe the diversity among Japanese White-eye populations. With this project I hope to answer many questions, including questions addressing dispersal and reproductive isolation. Although Japanese White-eyes are a species of least concern, my work could inform conservation efforts directed towards other White-eye lineages that are threatened or endangered. Follow me on Instagram.