Graduate Students

Current Graduate Students

Dalton Allen, MS 2021, PhD 2024

My name is Dalton Allen and I completed my undergraduate studies in Environmental Biology at Eastern Illinois University in 2018 prior to becoming a graduate student in the Jeffries lab. As my alma mater may suggest, I originate from the prairie state of Illinois, where I worked for the Illinois Natural History Survey (INHS) for around two years as both an intern and research technician. My research at TCU focuses on the development of alternatives methods for assessing the toxicity of effluent discharged into marine receiving environments. In my spare time, I enjoy fishing, playing video games, and listening/collecting records. My current tentative goal for the future is to pursue a career in industry.

Catherine Wise, MS 2025, PhD 2028

My name is Catherine Wise. I am originally from Houston, Texas, but I grew up moving between Texas, Ohio, and Pennsylvania. I received a BS in Neuroscience from TCU with a minor in Spanish for the Health Professions in 2023, and I am continuing my TCU career as a PhD student in the Jeffries Lab. During my time as an undergraduate, I participated in research in social psychology that allowed me to combine my interests in neuroendocrinology, neuroimmunology, and human behavior. As a second semester junior, I became interested in how endocrine disrupting compounds in the environment impact immune function, neuroendocrine development, and behavior, and I joined the Jeffries Lab. As a PhD student, I will be looking at the influence of maternal and early life stage glucocorticoid exposure on reproduction, stress reactivity phenotypes, and behavior of fathead minnows. When I am not in the lab, I enjoy cooking, building Legos, spending time with friends and family, and being outdoors.

Katie Solomons, MS 2025

Hi! My name is Katie Solomons and I am from Fairfax Station, Virginia. I am currently completing the degree requirements for my Biology BS degree and will begin the MS program in Biology next term. I joined Dr. Jeffries' lab in the summer of 2022 and worked with Dalton on a project investigating alternative methods in marine toxicity testing. As a MS student, I am working on using effects-directed analysis to identify and prioritize contaminants in the Trinity River watershed. On campus, I am involved in Alpha Phi Omega service fraternity and the pre-vet club. In my free time I like to volunteer at the HSNT animal shelter and spend time with my friends. After finishing my MS degree, I plan to attend veterinary school and eventually become a small animal vet.

Former Graduate Students

Rashidat Jimoh, MS 2023

Rashidat Jimoh received her BS degree in Environmental Toxicology and Conservation and MS degree in Environmental Toxicology from the University of Lagos (Nigeria) prior to completing her MS degree in Biology here at TCU. Rashidat's thesis research sought to validate the fathead minnow as a robust immunotoxicity model by showing that the immune responses of this species in response to exposures to glucocorticoids, which are known immunosuppressants, are predictable based upon what has been observed in higher-order species. In addition, Rashidat assisted with projects aimed at characterizing key differences in pathogen-stimulated immune function between male and female fish.

Austin Bryant, MS 2021

Austin Bryant received a BA in Biology from Salisbury University in 2014, and then spent two years working at Osiris Therapeutics and four months backpacking Europe before coming to TCU to pursue a MS degree. Austin's MS research sought to expand upon previous work done by Peter Bruns and Abbey Johnson, by determining the impacts of developmental thyroid disruption on various behaviors in fathead minnows. Austin's research revealed that early life stage thyroid disruption alters intra- and interspecific reproductive behaviors in male fathead minnows, helping to establish a link between the thyroid disruption-induced alterations in global gene expression patterns identified in Abbey's research and thyroid disruption-induced alterations in reproductive output observed in Peter's research. After graduating from TCU, Austin began a position at the United States Department of Agriculture's Dairy and Functional Foods Research Division.

Julie Krzykwa, MS 2017, PhD 2020

Julie Krzykwa received a BA in Biology from New College of Florida in 2012, and spent three years working for the Environmental Protection Agency before coming to TCU to pursue both MS and PhD degrees. Julie's MS and PhD research focused on the advancing the fathead minnow fish embryo toxicity (FET) test through the identification of sub lethal endpoints capable of improving the performance and predictive ability of the , such as growth related gene expression and developmental abnormalities, to improve the sensitivity of the FET test. Julie's work identified growth, eye size, and the pericardial area as potential FET test endpoints. Moreover, her results revealed that the inclusion of pericardial area as endpoint indicative of mortality enhances the sensitivity of the FET test making it comparable to other toxicity testing methods. After graduation, Julie spent ~3 years in the Ecotoxicology Department at Smithers Environmental Risk Science LCC in Wareham, Massachusetts, but now works as a Scientific Program Manager at the Health and Environmental Sciences Institute.

Leah Thornton Hampton, MS 2015, PhD 2020

Leah completed her MS degree at TCU and PhD at University of North Texas (UNT) under the supervision of Dr. Jeffries and Dr. Barney Venables (UNT) after completing a Zoology degree from Miami University (Oxford, OH). Leah's MS research focused on elucidating the differential reproductive effects of polybrominated diphenyl ethers (PBDEs) exposures during early development and adulthood. The results of her work demonstrated the enhanced vulnerability of early life stage organisms to the reproductive impacts of PBDEs. As a PhD student, Leah's work focused on the development of the fathead minnow as a model system for immunotoxicity and on the effects of early life stage thyroid disruption on immune system development. Leah's research in this area expanded the utility of the fathead minnow as a model for immunotoxicity studies and provided evidence that early life stage thyroid disruption leads to alterations in various aspects of immunity, particularly at the molecular and cellular levels. Upon graduating, Leah began a position as a Scientist in the Department of Toxicology at the Southern California Coastal Water Research Project in Costa Mesa, CA.

Lynsey Malin, MS 2020

Lynsey Malin graduated with BS degrees in both Biology and Entrepreneurial Management from TCU. During her time as an undergraduate, Lynsey pursued research and elected to stay at TCU after graduation to pursue an MS degree. Lynsey's MS thesis project sought to determine the influence of estrogen on immune function in fishes. Specifically, she examined how chemically-induced reductions in estradiol levels influenced pathogen resistance, phagocytic cell activity, respiratory burst activity, and immune-related gene expression in female fathead minnows. In her free time, she enjoys cooking, traveling, and trying new restaurants. Lynsey began medical school at the University of Minnesota after graduating from TCU.

Abbey Johnson, MS 2019

Abbey began her MS degree at TCU after graduating from the University of Texas with a BS in Marine and Freshwater Biology. As an undergraduate, Abbey gained research experience in fish physiology while working on a research project studying the effects of hypoxia on the oxygen carrying capacity in red drum. As an MS student, Abbey was co-advised by both Dr. Jeffries and Dr. Matt Hale and worked on a project aimed at connecting developmental thyroid disruption in fathead minnows to impaired reproductive success. Specifically, she analyzed brain transcriptomes from males exposed to thyroid disruptors during early development to identify possible mechanisms that lead to the reductions in fecundity. Her work provided evidence that thyroid disruption during early life stages has the capacity to alter various aspects of brain development, including neurogenesis and brain sexual differentiation. After graduating from TCU, Abbey took a position as an ORISE fellow at the United States EPA in Duluth, MN.

Kyle Roush, MS 2018

Kyle Roush began his research in the Jeffries lab as a sophomore and recently graduated with an MS degree. As an undergraduate, Kyle completed a Senior Thesis project titled Enhancing the fish embryo toxicity test: Growth, developmental abnormalities and gene expression as additional endpoints, which focused on using sublethal measures as test endpoints for a relatively new alternative toxicity testing method, the fathead minnow fish embryo toxicity test. As a graduate student, his research focused on improving endocrine disruption screening assays by identifying biological factors that influence test outcome. Specifically, his MS thesis work sought to understand how the reproductive status of fish used in such assays influences their response to compounds that interfere with sex steroid hormone signaling. After graduation, Kyle began a career as an Environmental Scientist at Procter & Gamble in Cincinnati, OH.

Peter Bruns, MS 2017

Peter joined the Jeffries lab after graduating with a Zoology degree from Texas A&M where he conducted research in a plankton ecology lab. Peter graduated with a MS degree in Biology from TCU in 2017. His thesis project examined the effects of model thyroid disruptors on reproductive endpoints in fathead minnows and showed that early life stage exposures to thyroid inhibitors impair reproductive success later in life. After the completion of his degree, Peter enrolled in the Environmental Science PhD program at Baylor University.