For evolutionary biologist Toby Kiers, Ph.D. ’05, winning a — “genius grant” — came as a total shock.
“I was stunned,” said Kiers, a professor at Vrije Universiteit Amsterdam. “I think it’s the mystery of the process that makes winning the fellowship so exciting because there’s no application, no forms, you have no idea who nominated you. It’s magic.”
Kiers is one of for exceptional creativity, promise for important future advances and potential for the fellowship to help their work. The prize comes with $800,000 over five years, no strings attached. In Kiers’ case, it marked the first time the John D. and Catherine T. MacArthur Foundation recognized someone who studies fungi.
Based in Amsterdam, Kiers investigates symbiotic relationships among plants, fungi and other microbes with a focus on the underlying cooperation that has evolved over hundreds of million years old. There are climate implications because plants take in large amounts of carbon from the atmosphere that they feed through their root systems to mycorrhizal networks. In exchange, the fungi are foraging for phosphorus and nitrogen and feeding them to the plant.
“One of the most recent papers we put out found that they move about 13 billion tons of CO2 every year out of the atmosphere and into their networks,” Kiers said. “That's like a third of emissions from fossil fuels. So massive amounts of carbon are going down to these fungal networks.”
With collaborators in biophysics, the researchers can see the exchange of resources with high-resolution imaging tools to track and quantify trade processes. Kiers has borrowed from economic theory to test trade predictions.
“I guess the thing I've learned is that the fungi are not passive accessories of plants, but they're really dynamic, powerful actors that move massive amounts of carbon,” she said.
Kiers discovered the diversity below ground when she was just a teenager. She took a year off from her undergraduate studies at Bowdoin College in Maine to go to Panama with the Smithsonian Tropical Research Institute. There, she helped with seedling experiments to understand if there was specificity in fungi relationships.
After finishing at Bowdoin and taking a year off, she arrived at UC Davis. She studied under R. Ford Denison, now professor emeritus in plant sciences.
“His work really excited me because he already was using evolutionary theory to understand resource trade between organisms and this idea of sanctions and punishment in nature,” Kiers said.
She said when she visits UC Davis these days, she said people immediately recognize a close relation: Her sister Haven Kiers, associate professor in the Department of Human Ecology.
“We look a lot alike,” she said. “We're only two years apart, and we have a lot of similar mannerisms.”
In 2021, Kiers co-founded the , or SPUN, to map and protect the Earth’s underground fungi. SPUN has given 137 grants to scientists who are mapping fungi in their local environments. She’ll team up with them for expeditions that have taken her to such far-flung places as Mongolia, Tunisia, Ghana and Ecuador.
Using data they’ve collected and putting them in machine learning models, she estimated that only 10% of biodiversity hotspots for mycorrhizal fungi are in protected areas.
For example, in California, there is more information about the mycorrhizal fungal communities in the soil there, but many are under threat. Kiers said threats include increases in soil temperature, land use change and pollution.
“We try to get these maps into hands of decision-makers and say, ‘here's a potential biodiversity hotspot below ground in an area that we predict is very threatened.’ These are communities that need to be studied and studied fast.”
For her work, she was awarded the Spinoza Prize, the highest distinction in Dutch science, in 2023.
“There's just so much to discover, especially about fungi,” Kiers said. “They show their secrets quite slowly; you need a lot of patience to work with these types of fungi. They're very slow growing, but when you do start to understand their inner lives, it's just completely captivating.”