Johanna Schmitt, a plant geneticist and evolutionary ecologist at UC Davis, has focused her career on understanding how plants adapt to their environments and how they might respond to climate change. Schmitt, known as Annie among friends and colleagues, has long been interested in phenotypic plasticity—how plants alter their growth patterns depending on environmental conditions.
“I’ve always been interested in the question of, are plants adapted to the environments they live in?” she said.
Her research has taken her across the United States and Europe, where she has studied wildflowers such as thale cress and mountain jewelflower. She investigates how these species grow differently with changes in temperature, rainfall, and seasonal timing.
“One of my contributions is just this idea that phenotypic plasticity is a trait that in itself can evolve,” Schmitt said. “And that led into being interested in how the effects of genes depend upon the environment, what are the specific genetic mechanisms that allows plants to sense and respond to environmental signals, and what are their effects on fitness?”
Schmitt’s work suggests that plant adaptation offers insight into potential responses to ongoing climate change. For instance, she notes that later rainfall in California shortens the growing season for many plants.
“The plants try to catch up,” she said. “They accelerate their flowering to get some seed production in, but that plasticity can’t entirely compensate for the shorter growing season and they don’t make as many seeds.”
One experiment led by Schmitt involved growing multiple genetic lines of thale cress from across Eurasia’s climate range in experimental gardens located from Spain to Finland. The results showed that varieties from warmer areas outperformed local ones in warming climates.
“In Germany, it wasn’t the German ones that did the best, it was the Spanish ones,” she said. “As it’s gotten warmer, the local populations have not evolved fast enough to keep up with the changing climate.”
Schmitt traces her interest in plant biology back to an undergraduate taxonomy class at Swarthmore College. The course and its instructor left a lasting impression on her career path. After earning a Ph.D. at Stanford University and conducting further studies at Duke University, she spent three decades at Brown University mentoring students and researchers before being elected to the National Academy of Sciences in 2008.
During her tenure at Brown University, Schmitt maintained a list of institutions that could persuade her to move; UC Davis topped this list due to its strong faculty in ecology and evolution as well as its reputation for plant biology research. She joined UC Davis in 2012.
“If you can just go along an elevational gradient and see all these different climates, then it’s perfect for studying climate change questions,” she said.
Now an emerita professor but still active in research at UC Davis, Schmitt expressed concern over recent federal funding cuts affecting climate change research.
“The climate is going to be changing faster because nobody’s putting a brake on it anymore,” she said. “So the need is really there.”
