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.

Former Graduate Students

Austin Bryant, MS 2021

My name is Austin Bryant and I am currently working on my Master’s of Biology in the Jeffries Lab. I grew up in Bel Air, Maryland and completed my undergraduate studies at Salisbury University receiving a B.A. in Biology in 2014. After my undergraduate studies I went on to work for Osiris Therapeutics, a company specializing in regenerative medicine products. I worked for Osiris Therapeutics for 2 years when I quit to pursue my dream of backpacking throughout Europe. I spent 4 months backing packing solo through Europe visiting a total of 14 countries and making countless memories. After completing my trip, I worked for another bio-pharmaceutical company, Janssen, which primarily made the drug Remicade. In 2019, I was accepted into the Jeffries Lab and began my research looking into the effects of early life stage thyroid disruption and its effects on neurodevelopment and behavior in fathead minnows. In my spare time I enjoy hiking, longboarding, reading, and surfing whenever I’m at the beach!

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. When not in the lab, Julie can be found baking, creating something, attending live music events, or SCUBA diving. She is currently holds a position in the Ecotoxicology Department at Smithers Environmental Risk Science LCC in Wareham, Massachusetts.

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. When Leah isn't in the lab, she enjoys being outdoors and looks forward to traveling and pursuing her love of scuba diving. She is currently employed 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 recently began medical school at the University of Minnesota and ultimately hopes to conduct clinical research as part of her career as a physician.

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 observed reduction in fecundity. Her work provided evidence suggesting that thyroid disruption during early life stages has the capacity to alter various aspects of brain development, including neurogenesis and brain sexual differentiation. It is hypothesized that such changes lead to alterations in male reproductive behavior and subsequent reductions in fecundity. In her free time Abbey enjoys traveling, reading, and being with friends and family. She is currently 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. Kyle served as an adjunct instructor for the Department of Biology's Contemporary Issues in Biology course prior to taking a position as an Associate 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. In his free time, he likes to play with his dog, watch sports, look at funny pictures on the internet, and SCUBA dive whenever the chance arises.