When Tom Fleischner started teaching students about a biodiverse Arizona landscape, he found a place with no name and little work by other scientists.

The region, sometimes called the Arizona Central Highlands, was seen as a boundary between two places. To draw more attention to it, Fleischner gave it a more evocative name: the Mogollon Highlands.

He also launched the Natural History Institute in Prescott as a way of helping people learn more about the region, it’s art, science and humanities.

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The Arizonans leading on climate are not always those holding protest signs outside polluting corporations, introducing regulatory legislation or planting shade trees in overheated neighborhoods. They can also be the people quietly counting snake and conifer species deep in the woods to shine a new light on unappreciated ecoregions.

When he’s not writing books about nature, teaching environmental science at Prescott College, directing biodiversity art installations, leading ecological immersion trips to Ecuador or playing drums in his improv band, Moving Edge, Tom Fleischner is doing that slow, tedious science necessary for Southwest climate resilience.

When he arrived in Prescott 37 years ago, after growing up in Ohio and studying marine mammals and seabirds in western Washington, he didn’t know much about the region. But having accepted a job teaching students about their natural surroundings, he figured he’d better dive in and learn all about it.

What he found shocked him. The diverse habitats along the geologic shelf that cuts diagonally from southwest New Mexico up through the Prescott area of Arizona along parts of the Mogollon Rim seemed “perfectly adapted for climate resilience.” Yet, there were no books about it. And ecologically, it didn’t even really have a name.

“It’s right where the Sierra Madre feeds in all this incredible biodiversity. You have genetic stocks from plants all over North America and Mesoamerica meeting here,” Fleischner said. “Part of what makes this such a rich area is all the topographic (elevational) diversity, but you could have that at another place and it wouldn’t be nearly as rich.”

The region, sometimes referred to as the Arizona Central Highlands, encapsulates the edge of many species’ ranges, he said (it also inspired his band’s name, Moving Edge). It’s the northern limit of the alligator juniper, Juniperus deppeana, common in Prescott. It’s the southern limit of Ponderosa pine, Douglas fir and white fir. It represents the westernmost occurrence of some great plains grasses as well as the edge of many Rocky Mountain species.

“When you zoom in and start looking at it and thinking about it, it becomes this incredibly biodiverse and continentally significant ecotone,” Fleischner told The Arizona Republic, adding that such range limits are often valuable for studying how species respond to environmental shifts like the average temperature increases brought by climate change.

“It’s this incredible mixing and this big spot of rumpled Earth, a biogeographic crossroads,” he said. “That’s all been true forever, but people just weren’t paying attention to it.”

He hypothesizes that’s because this area has been skipped over as a result of where all the big research institutions were “plunked down.” Scientists from universities in Phoenix, Tucson, Flagstaff and Salt Lake City fanned out to study the landscapes surrounding those places. But they largely overlooked the band of highly diverse ecosystems cutting between them.

Right away, Fleischner felt like part of the problem was that the Arizona Central Highlands name wasn’t catchy. And it didn’t even reference its defining, elevated landscape element, which extends well into New Mexico.

“People perceived this region as a line on a map, a boundary between two places,” he said. “So I came up with this name, the Mogollon Highlands, which I think is just a beautiful word and also highlights the central feature of the Mogollon Rim. It’s kind of like, if you build it, they will come. Or if you name it, they will come.”

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The next step was to get that name enshrined in the scientific literature. Fleischner teamed up with other biologists in the area to pull together data on snake, conifer and bird species inhabiting the Mogollon Highlands in greater numbers than in nearby, more homogenous landscapes. They published their first paper using the name in 2017, and Fleischner has continued to study and speak about the region ever since, most recently at a science conference hosted at Northern Arizona University in September. The hope is that funding to study more species across the unique geologic band will follow.

“Names can frame our way of thinking in incredibly important ways,” he said.

In 2017, Fleischner’s other major project to encourage recognition of the Mogollon Highlands advanced from a program through Prescott College to a full-blown nonprofit organization dedicated to the region’s biodiversity. As founding executive director, he first launched the Natural History Institute in 2012 with a vision to integrate art, science and humanities.

In 2025, the mission continues in a regal, historic building with a stone exterior, a few blocks from downtown Prescott. Once a meeting house for the Church of Jesus Christ of Latter-day Saints, it now opens into an airy, bright venue for public science talks and displays designed to connect visitors to the natural world.

A “manzanita ball,” made from tree roots woven tightly together and shaved into a glossy sphere, sits in the foyer below a painting of a California Condor. A gallery space down a short hallway recently hosted an exhibit titled “Field Studies” that featured maps built into accordion books by Arizona artist and educator Daniel Mayer.

Fleischner’s wife, Edie Dillon, is also an artist in the Prescott community. So he inhabits a life surrounded by intricate, beautiful things. His favorites are housed upstairs in drawers, jars and cabinets lining a climate-controlled room.

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Most of the institute’s 12,000 biological specimens are plants, some assembled as a series from sites before and after wildfire. Others are even more historic, having been pressed for posterity by the famous botanical explorer Cyrus Pringle, who made a career of documenting North American plants in between being drafted (as a pacifist Quaker) into the Union Army during the American Civil War and his death from illness in 1911.

The collection, used primarily to train future generations of naturalists, also features various reptile species that sit labeled and preserved in jars on the counter of the teaching space. Wooden drawers with glass lids in a side room display taxidermied songbirds and hawks. Others showcase pinned butterflies, moths, wasps and bees.

With the help of student summer interns, the specimens have now all been digitized, their information put online as a backup preservation method. Arizona is a particularly hard place to keep biological collections in good condition, Fleischner said, because the humidity varies so dramatically. A facility like this also costs a lot to maintain and there aren’t many ways for it to generate income.

While Fleischner has been developing the Natural History Institute and writing books about appreciating nature (his fifth, “Astonished By Beauty: A Field Guide to the Practice of Paying Attention,” is due out in Spring 2026), national natural history collections have been in decline. Funding cuts and a shift to genetic studies have caused young researchers to see little promise in the work, as trained naturalists retire.

For the past decade, scientists have been raising the alarm about this “institutional and ethical” concern and urging the public to support collections before their loss limits the ability of future generations to compare past samples to better understand global change.

That change is coming ever faster now, with atmospheric warming caused by burning fossil fuels resulting in heat waves, wildfires and storm surges that break new records nearly every year. The Trump administration recently suspended the National Oceanic and Atmospheric Administration’s calculation of billion-dollar weather disasters.

Meanwhile, the cost to taxpayers of climate-intensified weather events has spiked from about $22 billion per year in the 1980s to $149 billion annually since 2020. Naturalists argue that maintaining and expanding collections would cost a tiny fraction of this amount while greatly improving scientists’ ability to track and plan for related ecosystem collapse.

Standing amid the relatively small but enduring collection he’s assembled within the previously overlooked Mogollon Highlands to which he gave name and recognition, Fleischner called the decline of past, present and future biodiversity records a “crisis.” He worries about protecting the knowledge, funding and tools needed to study and respect the natural world. With the odds against him, he’s placed his bet on human nature.

“I think there’s a natural human inclination to be fascinated by biodiversity,” he said. “And I think it’s really easy to recharge that in people. That’s kind of what the institute and my life’s work is all about.”

Joan Meiners is the climate news and storytelling reporter at The Arizona Republic and azcentral.com. Her award-winning work has also appeared in Discover Magazine, National Geographic, ProPublica and the Washington Post Magazine. Before becoming a journalist, she completed a doctorate in ecology with a focus on native bees. Follow Joan on Twitter at @beecycles, on Bluesky @joanmeiners.bsky.social or email her at joan.meiners@arizonarepublic.com.