The key to surviving climate change? That would be the ability to respond and adapt.
As the two speakers at the Irving Institute's June Faculty Seminar explained, adaptation and response are as important for both humans and tiny fruit flies.
Can animals respond to climate change by evolving new traits that help them survive?
That's the question being explored by Emily Behrman, an assistant professor in the department of biological sciences. In her June Faculty Seminar presentation, entitled "Rapid Evolution in Response to Climate Change," Behrman answered yes—at least for the type of Drosophila fruit fly she's been studying.
While evolution occurs at the genetic level, its changes are then transferred to an organism's observable traits, or phenotype. So Behrman is exploring two related questions: How are genes transferred to the phenotype? And how quickly does this process occur?
Behrman's working hypothesis: As the seasons change, natural selection favors different phenotypes to survive in different environments.
Fruit flies make an excellent study of real-time evolution due to their rapid life cycle. A new generation can come along in as little as 10 days, with each generation experiencing different environmental selection.
Still, the research takes time. Behrman has been collecting fruit flies in the wild since 2009. To ensure their changes are based on genetics, she keeps the flies in the lab for at least four generations.
Behrman's research team also collects environmental data to assess how variations in precipitation, wind force, and air temperature affect the flies' evolutionary changes. These factors can create different needs. For example, during a harsh winter, flies with greater resistance to cold, starvation, and other traits are more likely to survive to the following spring. Then they can reproduce, passing their winter-resistant genes on to the next generation.
However, it's more complicated. Behrman has found that while summer and winter both affect fruit fly evolution, they do so in different ways. "Summer and winter have two separate sets of drivers," Behrman said. "Different variables are working at different rates."
Another of Behrman's findings: Adapting to changing climate is not only about evolving better defenses to physiological stress. The data also show genetic changes that affect how fruit flies sense and respond behaviorally to their environment. In other words, adaptation is not only about handling stress better–it's also about reading the room better.
Changing seasons can even affect the characteristics of a new generation, Behrman said. For example, flies born in the fall have what's known as higher plasticity, meaning they can respond to the environment in ways that may not be permanent. By contrast, those born in winter display more variation in phenotypes, possibly to diversify their survival traits.
How about extreme weather events, such as an especially cold polar vortex or unusually severe drought? "That's definitely contributing to environmental variation in phenotypes," Behrman said. "Though different lengths of events would have different effects on each generation."
When it comes to human responses to severe weather, good science alone isn't sufficient. Also needed are community engagement, partnership, and action.
That was the essence of the second Faculty Seminar presentation, delivered by Erich Osterberg, a professor of earth and planetary sciences. He included this sentiment in his talk's title: "Flood Physics to Community Resilience: Why Good Science Isn't Enough."
Osterberg explained that in the Upper Valley of New Hampshire and Vermont, heavy rainfall can result from three types of storms: summer thunderstorms, nor'easters, and the remnants of hurricanes. While the number of storms in the area has not increased, the amount of rain they're dumping has. That's due to climate change, Osterberg said, and the warming atmosphere.
Heavy rain, in turn, can wreak two types of damage: inundation and erosion. With inundation, buildings, roads, and other infrastructure are literally submerged underwater. With erosion, those same infrastructure elements are undercut and washed away, getting damaged or destroyed.
Scientists, meteorologists, and others have gotten pretty good at predicting storm-driven inundation, and Osterberg's team is working to improve predictions of erosion. But "prediction isn't the whole solution," he added. Also needed is a plan for action, one the community supports.
How to achieve this? Since 2012 Osterberg and his colleagues have been convening workshops and meetings across the Upper Valley. They've invited a wide range of participants, including state and municipal professionals, local planners, nonprofits, emergency responders, and residents. A typical workshop attracts anywhere from 50 to 150 participants.
Workshop participants discuss flood-related issues that include:
Larger regional meetings have been convened, too. The most recent, held at Dartmouth late last year, was sponsored by the Irving Institute. The meeting ran for two days and attracted 175 practitioners. Another such event is planned for May 2027 in Manchester, N.H.
Osterberg is also training Dartmouth students in community flood management and climate resilience. He and a departmental colleague, Carl Renshaw, have developed a two-term service learning course. Participating students not only study in the classroom, but also partner with local community groups to tackle real-world climate challenges together. The students also attend and host in-person events. "We're getting students out of the Dartmouth bubble and into the community," Osterberg said.
That's important. "Unless we work directly with communities to co-create and enact solutions," Osterberg said, "the best flood science is useless."
Watch a video of the Irving Institute's June Faculty Seminar
Peter Krass is a contributing writer and editor to the Irving Institute.