This piece is adapted from the NHMU’s Science Stories blog.

Every summer, wildfire smoke blankets Salt Lake Valley, clouding Utah’s iconic mountains. While it may be easy to view fire as an enemy, it has been an essential part of Earth’s ecosystems for millions of years, playing a vital role in maintaining the health of forests and grasslands. Scientists around the globe are uncovering the complex interplay between wildfire, climate change, loss of plant-eating wildlife, and human activity to illuminate how we can help better foster the health and resilience of the natural world.

The Natural History Museum of Utah (NHMU) is showcasing this story in its rotating News from Our Scientists exhibit, exploring the pivotal roles wildfire and herbivores play in shaping certain landscapes. This exhibit highlights the work of Chief Curator and Curator of Paleontology Tyler Faith, Curator of Botany Mitchell Power and University of Utah undergraduate intern Eliana Massey. Based on research led by Faith, a U associate professor of anthropology, and funded by the National Science Foundation, the exhibit offers an engaging look at one of the world’s most critical natural forces.

Covering a large portion of the planet, grasslands are among the most flammable ecosystems. Grasses not only serve as fuel but also regenerate quickly after a fire, allowing the same areas to burn annually. Grazing herbivores such as wild ungulates can reduce available fuels and, therefore, help moderate wildfire activity. While it is well understood that grazers influence fire frequency on small spatial scales, Faith and his collaborators are exploring these native animals’ impact on continental scales. After gathering an extensive paleontological record of fossil and environmental data across the globe, they discovered a strong correlation between herbivore extinction and increased wildfire activity, demonstrating the critical role grazers play in regulating wildfires across entire continents.

Building on this discovery, the team dug deeper and analyzed records spanning the past 12,000 years in Africa to better understand how climate change influences wildfire patterns. This relationship proved to be more complex than it might initially seem. In arid environments where the amount of fuel is a limiting factor, long-term increases in rainfall due to climate change promote plant growth, enhancing fuel loads and leading to greater fire activity. Yet, in wetter environments, the limiting factor shifts to fuel moisture, and increased rainfall leaves fuels too wet to burn. This means the potential of fire is not simply determined by changes in fuel load alone but by the delicate balance between fuel availability and fuel moisture. After refining this model, the team applied it to wildfire records across Africa and documented a relationship between climate change and the frequency of wildfires.

With these insights in hand, the team shifted their focus to quantifying how much available fuel grazers consumed and, consequently, the extent to which herbivore extinction—driven by climate change and human activity—effects wildfire patterns today. Throughout the last year, they have combed through literature from the past century to find observations on vegetation consumed by grazers, using this data to develop a more reliable model for such calculations. While other scientists’ efforts have heavily relied on both experimental and theoretical work, neither approach has proven to be entirely adequate for large-scale generalizations.

While this project remained underway, Faith began collaborating with others at NHMU to share his findings with the public. After taking Faith’s Intro to Museum Collections class, Eliana Massey was offered an internship to help design the new exhibit.

“It was a unique and cool internship—it’s not very often that you get to see a project from the beginning to the end, especially at such a large Museum,” Massey explained. She played a key role in nearly every aspect of this exhibit, including the process of extracting a lake sediment core—a valuable paleoenvironmental proxy—for display.

Sediment cores provide an extraordinary window into the past, preserving a wealth of information about the natural history of the surrounding area. Within the cores we can find layers of charcoal derived from wildfire, pollen from vegetation, and spores from fungi found only in herbivore dung to give a detailed view of what the local landscape looked like and how it changed over time. Scientists can build an age-depth model, dating the sediment layers by every 5 to 10 centimeters of core to construct a detailed timeline of environmental history, resulting in an invaluable tool.

Power, a professor in the U’s School of Environment, Society & Sustainability, led a research field trip to Tony Grove Lake in Logan Canyon. The team used specialized equipment to extract two cores with thousands of years’ worth of sediment record.

While Power is well-versed in extracting sediment cores, preparing them for display presented a new, yet crucial challenge—how do you showcase a meter-long column of mud? Asked by colleagues on several occasions to find a way, Power developed a method to stabilize the cores and safeguard them from mold and other environmental damage. This effort involved close collaboration with NHMU’s Exhibits Team, particularly Assistant Exhibit Developer Casey Clifford, who conducted extensive research on potential display methods. The team ultimately chose an epoxy substrate, carefully piping in a mixture of acetone and Paraloid (a thermoplastic resin) in a series of steps to solidify and reinforce the core. This method marks the first time the scientific community has successfully prepared a sediment core for display, and it’s now featured at the museum

“We are the leading edge of embedding mud with epoxy,” Faith said.

Cosette Reeves is NHMU’s Interdepartmental Administrative and Project Coordinator, where she collaborates on projects across all departments at the museum. The new exhibit, which includes an interactive video feature, can be found on the museum’s second floor. The research described here is funded by the National Science Foundation.

• Margaret Chamberlain public relations, Natural History Museum of Utah
  ‭(406) 581-0191‬ mchamberlain@nhmu.utah.edu