Evolutionary biologist Dr. Toby Kiers, a professor at Vrije University in Amsterdam, has recently been awarded the 2026 Tyler Prize for Environmental Achievement, often called the ‘Nobel Prize’ for climate, for her revolutionary work on the vast, hidden fungal networks that underpin life on Earth. Her research illuminates how these “invisible” ecosystems play a monumental role in regulating our climate by sequestering massive amounts of carbon. In this conversation, we explore the immense power of this underground world, discussing how these fungi function as a global carbon sink, the development of the first-ever ‘Underground Atlas’ to map them, the threats they face from human activity, and how understanding their intricate underground economy can reshape our approach to conservation and climate policy.
Congratulations on the Tyler Prize. You’ve brought attention to a world that is largely “invisible.” How do you make the critical importance of these hidden fungal networks tangible for policymakers, and what is your biggest challenge in getting people curious about what’s happening right under their feet?
Thank you. The greatest challenge is precisely that—making the invisible, visible. My aim has been to pioneer a completely new way of understanding life on our planet, but it’s difficult when the subject is hidden from view. My job has been to become something of an “Underground Astronaut,” pulling together a network of dedicated scientists and working with local collaborators worldwide to explore this frontier. The key isn’t just about presenting data; it’s about flipping people’s perspectives. I’ve found that the moment you can spark a sense of genuine curiosity about these complex, bustling ecosystems operating right beneath our feet, people are hooked for life. Once they grasp the wonder, the urgency to protect it follows naturally.
Your research highlights that fungal networks draw down a third of our annual fossil fuel emissions. Can you explain the biological process behind this massive carbon capture? What specific agricultural or forestry practices are most destructive to this vital, natural system?
It’s truly staggering to think about. These mycorrhizal fungi form a symbiotic partnership with plant roots, creating a vast underground circulatory system. In exchange for nutrients they provide to the plants, the fungi receive carbon. This process moves massive amounts of carbon from the atmosphere into the soil, where it can be stored. We’re talking about 13 billion tons of CO2 drawn down into soil systems every single year—that’s equivalent to a third of our global emissions from fossil fuels. Unfortunately, we’ve long neglected these systems, and they are now severely threatened by human activity. Widespread deforestation, soil erosion, and many modern agricultural practices literally tear these intricate networks apart, disrupting critical nutrient cycles and accelerating biodiversity loss.
The Underground Atlas is a groundbreaking project, given that less than 0.02 percent of Earth’s surface was previously mapped for these fungi. Could you describe the process of collecting this global data and how conservationists can use the atlas to protect these vital ecosystems?
It was a monumental task, especially considering that staggering figure—less than 0.02 percent of the planet’s terrestrial surface had been mapped for these fungi. To incorporate them into any meaningful climate strategies or conservation agendas, decision-makers desperately need access to high-resolution fungal data on a global scale. So we built a team, including my collaborator and biophysicist Tom Shimizu who led the robotic imaging, and began the work. The Underground Atlas charts the global distribution of these fungi, essentially providing a roadmap for conservationists. It allows them to identify biodiversity hotspots and protect the most vital carbon stores, ensuring that restoration and conservation efforts are guided by actual data about the life underground.
You discovered that fungi actively trade essential minerals like phosphorus for carbon from plants. Could you elaborate on this underground economy? How does understanding this symbiotic relationship change our approach to soil health, biodiversity, and even climate policy?
It’s a dynamic, living marketplace. Through our lab experiments, we observed that the fungi aren’t passive participants; they actively manage their resources. They move phosphorus, an essential mineral for all life, from areas where it is abundant to areas where it is scarce. In return for delivering these crucial nutrients, they absorb more carbon from the plants they partner with. Understanding this intricate trading relationship completely reframes our view of soil. It’s not just dirt; it’s a complex economic system. This knowledge underscores that a healthy planet requires healthy soil, which in turn depends on these symbiotic partnerships. It shows us that to tackle biodiversity loss and the climate crisis, our policies must extend beneath the surface and protect the very foundation of our terrestrial ecosystems.
As you look to the future, you mentioned the prize money will help you “dream.” What specific research questions or projects do you hope to pursue next to expand our understanding of these networks and their role in a healthy planet?
For a scientist, the opportunity to simply dream is an incredible gift. We are often so focused on the immediate demands of research and funding that we don’t get the space to think bigger. This prize gives my team and me a chance to take a deep breath and push the boundaries of what we know. We want to delve deeper into the behaviors of these networks, to understand their resilience in the face of climate change, and to explore how we can actively harness their power for large-scale ecological restoration. The goal is to continue pioneering this new way of seeing life on Earth and translate that understanding into actionable strategies for a healthier planet.
What is your forecast for the role of fungal science in global climate strategies over the next decade?
I believe fungal science is poised to become an absolutely central pillar of our global climate strategies. For too long, we have neglected this critical component of our planet’s carbon cycle. As the data from projects like the Underground Atlas becomes more accessible, policymakers will no longer have an excuse to ignore the world beneath their feet. I forecast that within the next decade, protecting and restoring fungal networks will be integrated into international conservation agendas, carbon credit markets, and regenerative agriculture policies. We will move from simply acknowledging their existence to actively leveraging their immense power to draw down carbon, enhance biodiversity, and build more resilient ecosystems. This “invisible” world will finally become a visible and indispensable ally in our fight against the climate crisis.
