Current - Graduate students

Interested in joining the lab? Please contact me via email.

Leila Wahab

PhD Candidate, Environmental Systems Program - University of California, Merced 

Bio: Leila is a PhD Candidate studying carbon and nitrogen cycling in grasslands and how that will be affected by climate change. She is working on a dissertation centered around the impacts of changing amount and seasonality of precipitation on both surface and deep soils. In her free time she enjoys escaping to the Sierras with her pup and making art

HyeJoo Ro

PhD student, Quantitative Systems Biology Program - University of California, Merced 

Bio: I am broadly interested in trophic ecology, especially predator-prey dynamics. I became interested in stable isotope research because it allows for the flexibility to work and think about a wide variety of systems from terrestrial, freshwater, or marine. I graduated undergrad in 2019 from the School of Aquatic and Fishery Sciences at the University of Washington. Outside of research life, I enjoy traveling, swimming, and reading.

Jon Kuntz

PhD Candidate, Environmental Systems Program - University of California, Merced 

Bio: Jonathon Kuntz is a stable isotope ecologist interested in the life history of sharks. In 2017, he received a BSc in environmental and organismal biology from the University of Utah. He has since worked with chronological tissues of endangered and threatened species in the San Francisco Estuary, using stable isotopes to better understand movement and trophic interactions across space and time.

Gabriele Larocca Conte

PhD Candidate, Environmental Systems Program - University of California, Merced 

Bio: I received the Bachelor Degree in Natural Sciences and the Master Degree in Geosciences, focusing on biodiversity and palaeocology of ancient shark communities from Italian Fossil Lagerstätte. My goal is to unearth the mysteries of the past, considering environment and animal communities as a whole system. I am now interested in stable isotope applications on shark teeth for paleoenvironmental and paleoecological purposes.  I do love hiking, as well as I do love music. I am a drummer in the spare time.   

Dr. Robin B. Trayler

SIELO Director and Project Scientist - University of California, Merced 

Bio: I am interested in paleontology, paleoclimatology, and paleoecology. I use a variety of techniques in my research including stable isotope geochemistry, radiogenic isotope geochemistry, electron microscopy, and a variety of modeling techniques. (website)

Current - Undergraduates


Gina Palefsky, PhD Interdisciplinary Humanities - University of California, Merced (primary advisor: Dr. Christina M. Torres)

Bio: Gina studies human dietary practices during the Iron Age in central Thailand (c. 500 BCE – CE 400). She is broadly interested in bioarchaeology, archaeology of food, human-environment interactions, and archaeological applications of stable isotope analysis. She is now a Senior Archaeologist at the Augustana University

Rachel Chan, former MS student at University of California, Merced 

Bio: I received my BS in chemistry with a focus in environmental chem, and minored in geology and biology. I enjoy applying chemistry to outside the lab because it’s like trying to find the next piece to a puzzle. I’m interested in paleoclimate reconstructions, geochemistry, marine ecology, stable isotopes, and climate change. I half-jokingly say I’m an aspiring climbing climatologist.

Molly Karnes, former MS student at University of California, Merced 

Bio: Molly is interested in modeling paleo food web dynamics and including morphological and stable isotope parameters to account for  shark body size, environmental variation, and trophic level.

Maya Morris, former Undergraduate researcher

Graduate student at UC San Diego

Bio: I am a chemistry and physics major with an interest in becoming a professor in the future. Currently I am conducting research on fossilized and modern ray teeth using both SEM and XRD analysis. Outside of classes my hobbies include working out, cooking/baking, painting, and spending time with friends and family.

Alyssa Valdez, former Junior Research Specialist

Graduate student at UC Riverside

Bio: I am a recent graduate from UC Merced with a BS in Earth Systems Science. I enjoy studying different environmental systems and understanding their interconnectedness: whether it be about deep sea sharks or the nitrogen cycle in soil. I am passionate about advancing science to help make it more equitable and sustainable for every being. I hope to pave a path for more aspiring scientists of color and open up conversations about the connection between climate and racial justice.

Pedro Valencia Landa , former Undergraduate researcher 

Graduate student at UC Santa Cruz

Bio: My ultimate goal is to be able to give back to the underrepresented community by helping the next generation of researchers and doctors accomplish their dreams while bridging the ethnicity gaps currently present in medical fields and higher education. Currently, I am conducting research to  understand the process of demineralization for stable isotope analysis. My hobbies include: exercising, running, wondering, and drawing.

 Eva Lyon, former Graduate student at University of Kentucky

Assistant Professor, Ohio University

Bio: I am driven by a great curiosity about processes of change in the natural world, whether anthropogenic, or driven by natural cycles. My research uses geochemical and physical analyses of sedimentary records to discern climatic and environmental change at various temporal and regional scales. My current project explores the glacial history of the Eastern Sierras in California using the sedimentary record of June Lake, CA. 

 Sarah Zeichner, former undergraduate researcher at Univ. of Chicago

PhD student at CalTech.

Bio: My research uses stable isotope analysis as a tool to explore the connection between  shark ecology and environment with shark teeth isotopic composition. Past projects include: (1) Biological parameters based on organic carbon and nitrogen isotopic values to interpret modern shark ecology (based on teeth taken from a captive feeding experiment), and (2) Eocene high-latitude temperature gradients over time and space based on oxygen isotope values of fossil shark teeth and bivalves from La Meseta formation in Seymour Island, Antarctica.   

Lana Krol, DVM, former undergraduate at the Univ. of California, Santa Cruz

Veterinarian, Steinhart Aquarium at the California Academy of Sciences

Bio: As an undergraduate at UC Santa Cruz, I joined Sora as a student researcher for her PhD dissertation project. She was a superb role model who encouraged her team to formulate new ideas and think outside of the box. Working with her was the boost I needed in deciding to work intimately with animals and apply for veterinary school. A decade later, I am lucky to have her as a friend and sounding board. 

photo credit and an article about Lana's current work -