Cautionary Tales of the Prehistoric Past: Bridging Deep Time and a Changing Planet
For Dr. Larisa DeSantis, the prehistoric past is as important as the study of our historic past—the fossil record holds an archive of cautionary lessons that our planet desperately needs us to read. Reading the record, is much like deciphering ancient languages, we have to use tools like stable isotopes or the microscopic wear patterns on teeth to infer the ecology and biology of ancient plants and animals.
DeSantis is a conservation paleobiologist and vertebrate paleontologist whose scholarship defies easy categorization. Working at the crossroads of biology, geology, and conservation science, she analyzes the fossil record to illuminate how ecosystems and species have responded to dramatic climatic shifts across thousands to millions of years—and then asks the harder question, What does that mean for the world we’re living in right now?
Her intellectual journey was shaped by an early and enduring fascination with prehistoric life, one that eventually collided with an equally powerful commitment to conservation. Rather than choosing between the two fields that used to be mutually exclusive in scope, DeSantis built a career around their intersection. She holds advanced training in both paleontology and environmental management, and her path through institutions including UC Berkeley, Yale, and the University of Florida, helped her speak different disciplinary-specific languages.
“My research really came from a struggle, from trying to choose between my passion for studying the past and my desire to conserve species for the future,” DeSantis says. Today, she asks questions of relevance to conservation biologists, using the fossil record to answer those questions.
Research That Speaks to the Climate Crisis
DeSantis’ work holds relevance for students and scholars in Climate and Environmental Studies. Her research examines how past episodes of climate change—including large-scale aridification events and/or dramatic upticks in fire severity—reshaped what animals could eat, where they could survive, and how entire ecological communities organized themselves. By reconstructing these ancient responses, her lab generates insights that directly inform modern conservation strategy. DeSantis runs the DREAM lab which stands for Dietary Reconstructions and Ecological Assessments of Mammals, where she and Vanderbilt students are engaged in scientific research and public outreach.
“Clarifying the past can help us better understand what options species may have in the future,” DeSantis has noted, “and even get creative about potential species and/or ecosystem specific management plans.”
This is not merely retrospective science. At a moment when climate change and biodiversity loss are unfolding simultaneously and at accelerating speed, the ability to draw on 65-million years of ecological precedent is a powerful tool, one that DeSantis is uniquely positioned to wield.
Recognizing Excellence: The 2025 Guggenheim Fellowship
DeSantis was named a 2025 Guggenheim Fellow (part of the 100th class of scholars and artists). The fellowship is supporting her work on a forthcoming book—tentatively titled Decoding the Dead: Revealing Our Past to Conserve Our Future—that will bring her research to a broad public audience. The project, also backed by a grant from Princeton University Press, will trace Earth’s history from the final era of the dinosaurs through the rise of mammals, weaving in contemporary scientific discoveries and centering voices of researchers who have historically been underrepresented in earth and biological sciences.
What This Means for Climate and Environmental Studies
DeSantis exemplifies the kind of integrative thinking that climate and environmental studies increasingly demands. Her work challenges students to consider environmental challenges not just as present-day crises but as moments within a much longer arc of planetary change—an arc that carries both warnings and hopeful stories of survival.
Larisa DeSantis is an Associate Professor in the Department of Biological Sciences and the Department of Earth and Environmental Sciences at Vanderbilt University’s College of Arts and Science. She is an affiliate of Vanderbilt’s Program in Climate and Environmental Studies.