As a kid, Megan Vahsen was really interested in science and math, and she was good at them. So when she went to college, it made sense to major in pre-med—until the day when an advisor asked, “Why do you want to be a doctor?”

That question made her realize that she didn’t have an answer, and the advisor recommended that she try research. Vahsen applied to a National Science Foundation Research Experiences for Undergraduates program at the University of Nevada, Reno. It was a plant community ecology project with a lot of independent fieldwork.

“That was my first fieldwork experience doing ecology,” she said. “And I got hooked.”

Searching for the why

Vahsen, now an assistant professor in the Odum School of Ecology, studies how plants respond to climate change and the impacts of that change on ecosystem function—a path whose roots can be traced back to her REU experience. After completing the program, she finished her B.S. in biology at the College of William and Mary and then pursued an M.S. in ecology at Colorado State University.

At Colorado State, she was sampling vegetation plots and noticed an invasive plant in all the plots—cheatgrass, which is common in the intermountain west. Cheatgrass settles in early, flowers and goes through its lifespan more quickly than other plants, so it cheats out the native vegetation.

Her advisor, Ruth Hufbauer, focused on invasive species both in the field and in the lab, so Vahsen had access to a flour beetle system that allowed researchers to ask questions about how populations of organisms establish and what makes them successful. Is it just pure numbers? Do you need genetic diversity? Does the quality of the environment matter?

“I’m just always curious about the why of things,” she said.

In the lab, flour beetles can have a short life cycle—six generations in six months—and are easy to count. Vahsen reared colonies of them, manipulating their genetic diversity by adding and subtracting individuals and watching to see how the population changed over time. A lot of her work with the beetles was focused on evolutionary implications, exploring not just if the population survived, but if it evolved in response to a change in environment.

“We think that invasive populations come into a new area and have to adapt really fast or they won’t survive. I became really interested in not only ecology, but evolutionary ecology, and that’s what led me to my Ph.D. work, which focused on plants rapidly evolving,” she said.

“One of the biggest things that we think could be promoting evolution is likely climate change. A big change in the environment might manifest a change in populations of plants.”

Making math and stats fun

Vahsen earned a Ph.D. in biology at the University of Notre Dame, working with advisor Jason McLachlan. She won the 2024 George Mercer Award, given by the Ecological Society of America to honor an outstanding ecological paper published by a lead author who is under 40 years old. Vahsen, who served as lead author, and her collaborators were recognized for their work Rapid plant trait evolution can alter coastal wetland resilience to sea level rise, published in Science.

After earning her doctorate, she served as a postdoctoral fellow at Utah State University (working on the same invasive plant, cheatgrass, that sparked her interest during her M.S.) and as adjunct faculty at Appalachian State University. Now setting up her own lab at UGA, Vahsen said she’s excited to work with like-minded people.

“My work is pretty interdisciplinary, so I look at how plants evolve, and then I also see what the consequences of that trait evolution is on big ecosystem process, processes like carbon sequestration and resilience to sea level rise,” she said. “I collaborate with both evolutionary biologists and ecologists, and the department here has the best of both of those.”

She’s also looking forward to visiting the Georgia coast, where she plans to conduct research in marsh systems.

“A lot of my work historically has been in the Chesapeake Bay, but I’m hoping to kind of build out in the Georgia coastal system as well,” she said. “Everyone says it’s really beautiful, so I’m very excited.”

This fall, she’ll co-teach General Ecology with Alli Injaian. Vahsen is most experienced in teaching quantitative classes, and she hopes to help increase quantitative offerings for grad students and maybe undergrads as well. She loves teaching people how to code and trying to make math and stats more accessible and less scary.

“I think it can be really fun, but a lot of people don’t think that,” she said. “I like to try and change their mind.”