Texas Tech University

Robert D. Bradley's Laboratory

Joanna Bateman
Teaching Assistant

Ph.D. student, Biology, Texas Tech Universityjoanna bateman
M.S. Biology, Brigham Young University
B.S. Biology, Brigham Young University


I have been researching and constructing the phylogenetic trees of the Heteromys pictus-spectabilis species complex (Painted spiny pocket mice and Jaliscan spiny pocket mice) since 2016 working on my Master's thesis under Dr. Duke Rogers. I began working in Dr. Bradley's lab in 2018, with the main goals of my PhD dissertation research being to determine the actual number of cryptic species present within the complex, to estimate their geographic distributions, and to predict the divergence history of these populations. This builds upon past evidence I have found that this species complex is actually composed of multiple cryptic species, and thus is in need of taxonomic revision. These questions will be primarily addressed through genome (RADSeq) sequencing and geographic data (Cytb haplotype networks, geographic barriers, etc.), using specimens collected across the overall habitat range.

Emma K. Roberts

emma roberts

Postdoctoral Researcher, Texas Tech University
Ph.D. Biology, Texas Tech University
B.S. Biology, Texas Tech University


My research focuses on the molecular evolution of gamete recognition, specifically the sperm protein called zonadhesin, and its unique contribution to mammalian speciation and evolution. My post-doctoral work focuses on two main projects:

1) Determining the effect of climate change on zoonotic and pathogenic agents and wildlife species across latitudinal and temporal gradients, as well as different ecosystems in the south-central United States

2) Continuing my dissertation research on zonadhesin evolution. Specifically, I am investigating the origin of the gene that encodes zonadhesin across vertebrates, characterizing zonadhesin's role in speciation among mammals at different stages of divergence (older species, sibling species, and hybrids), and characterizing differential evolutionary pressures of zonadhesin (e.g., domain duplication, selection) as a mechanism to alter gamete binding specificity and therefore maintain a reproductive isolation barrier to fertilization.

Emily Wright
Teaching Assistantteaching assistant

Ph.D. student, Biology, Texas Tech University
B.S. Zoology, Texas Tech University


After graduating from TTU with a B.S. in Zoology, I remained in Raiderland and began my MS in the summer of 2016 in Dr. Bradley's lab.  My thesis research focused on hybridization between mule and white-tailed deer.  This research currently is in press at the Journal of Mammalogy and has led to several other research questions involving the detection of contemporary hybrids and characterizing the variation of the prion protein gene across geographic populations.  Although deer genetics remains one of my areas of research, Itransitioned to the PhD program in 2020 to focus on the genetics and genomics of Texas desert bighorn sheep.  My dissertation involves the use of ancient DNA and contemporary genetic variation to characterize population structure, connectivity, and systematic status of Texas desert bighorn sheep by mitochondrial DNA and RADSeq techniques.  I am also exploring the genetics of an exotic wild sheep (aoudad) using similar methodologies.  After completing my PhD, I plan to continue my education and pursue a Doctorate in Veterinary Medicine to specialize in the rehabilitation and reintroduction of species into their native habitats.  I am co-advised by Dr. Robert Bradley in the TTU Dept. of Biological Sciences and Dr. Warren Conway in the TTU Dept. of Natural Resources Management.