Biodiversity as Biosecurity: HowFungi Protect Ecosystems

In this 2014 interview, mycologist Paul Stamets argues that mycelial networks—the fine, cobweb-like fungal structures that permeate soils—function as Earth's biological internet, linking plant communities and enabling nutrient exchange and chemical communication between trees. With 40% of soil biomass being fungal and humans currently in the sixth mass extinction (losing approximately 30,000 species per year), Stamets contends that fungal biodiversity is not merely an environmental concern but a biosecurity issue. He presents mushrooms as allies in food security, medicine, and ecosystem remediation, while warning that the loss of soil microbiota through habitat destruction threatens the foundation of all terrestrial food webs.

Why Are Fungi So Understudied Despite Their Central Role in Nature?

Stamets traces his attraction to mycology to the fundamental mystery surrounding mushrooms. Mushrooms occupy a unique ecological space: they are potent—capable of killing, feeding, curing, or intoxicating—yet humans have far less cumulative experience with them than with animals or plants. Most fleshy mushrooms are ephemeral, visible for only four or five days before disappearing, which limits human familiarity and scientific investigation. The perennial wood-decay fungi (polypores and conks) have a longer history of human interaction, and thus more documented applications.

The gap in fungal knowledge is striking when one considers the sheer biomass at stake. Stamets emphasizes that approximately 40% of soil biomass is fungal, and roughly 70% of soil microbes are fungal organisms. These are not peripheral players—they are foundational. Yet because fungi live mostly underground or fruit briefly, they remain "understudied" relative to visible kingdoms. This knowledge gap is consequential because mycelial networks, though only one cell wall thick, are among the largest and most complex organisms on the planet.

What Is Mycelium, and How Does It Connect Ecosystems?

Mycelium is the vegetative part of a fungus—a network of fine cells that grows through soil and organic matter. To understand what it is, Stamets offers a simple exercise: find a piece of wood on the ground, tip it over, and observe the white, threadlike filaments coating its underside. Those filaments are mycelium.

The scale of mycelial networks is almost incomprehensible. The largest known organism on Earth is not a blue whale or a redwood tree, but a mycelial mat of honey mushroom in eastern Oregon, measuring 2,200 acres in size. Despite its vast extent, the mycelium remains only one cell wall thick—an extraordinary feat of biological engineering. On the other side of that fragile cell wall are hundreds of millions of microbes attempting to consume it, yet the mycelium persists and expands.

These networks connect entire forests. They serve as what Stamets calls "Earth's natural internet," a system for bidirectional nutrient transfer that supports plant communities. Unlike the human internet, the mycelial network is generative; it does not merely transmit information but actively nourishes the organisms it connects. When plants exchange nutrients via mycorrhizal fungi, both the fungus and the plant benefit—a classic mutualistic alliance.

How Do Trees Communicate Threats Through Mycelial Networks?

Beyond nutrient exchange, mycelial networks facilitate chemical communication between plants. When a plant is under attack by insects or facing other predation, it releases chemical signals that travel through the mycelium to adjacent plants, alerting them to the threat. This "wood wide web," as some researchers call it, allows plants to mount preemptive defensive responses before a predator arrives.

Stamets notes with some sadness that science is only now discovering mechanisms that have evolved over millions of years. The mycelium is simultaneously a nutritional highway and an early-warning system—dual functions that illustrate why the loss of fungal diversity threatens not only food production but the communication networks that hold ecosystems together.

Why Is Fungal Biodiversity a Matter of Biosecurity?

Stamets frames biodiversity loss not as an abstract environmental concern but as an acute biosecurity threat. He draws a striking parallel: if an asteroid 60 feet in diameter were on a collision course with Earth, all nations would mobilize to divert it. Yet humanity is currently experiencing a "proverbial asteroid"—the sixth mass extinction event in Earth's history. The planet harbors approximately 8.3 million species, and humans are eliminating roughly 30,000 species per year. At this rate, in 100 years more than one-third of the planet's biodiversity will be gone.

As habitats are destroyed—particularly old-growth forests and wetlands—the mycelial networks that sustain food webs erode "underneath our feet." The loss is not confined to charismatic megafauna. The microbes in soil, about which science has only preliminary knowledge, are disappearing at rates that will destabilize agriculture and human nutrition. Stamets stresses that "we are a community"—humans exist as symbiotic assemblies of roughly 10 trillion bacterial cells to 1 trillion human cells. Plants, soils, and all terrestrial organisms operate similarly. As we dismantle the microbial communities that underpin these relationships, we jeopardize not only other species but ourselves.

What Specific Mushrooms Offer Medicinal and Practical Benefits?

During the interview, Stamets brings three mushroom specimens to illustrate the range of fungal applications. The first is Agarikon (Fomitopsis officinalis), one of North America's rarest polypores, found only in old-growth forests. Prized for over 2,000 years, it once flourished in Europe but disappeared as forests were cut down and its habitat vanished. Research submitted to the biodefense program after 9/11 identified Agarikon as a potent source of antiviral compounds effective against pox and flu viruses.

The second is Turkey Tail (Trametes versicolor), which was the subject of a 2.2 million dollar NIH breast cancer clinical trial. Turkey Tail was found to upregulate the immune system and, when used in combination with chemotherapy, enhanced the positive effects of cancer treatment.

The third is Amadou (Fomes fomentarius), also known as the tinder conch. This fungus enabled the portability of fire—a critical survival tool for ancestral human communities. Before matches and lighters, the fire keeper of a tribe carried amadou to preserve embers and prevent the loss of fire, which was essential for keeping the clan alive through winters and migrations. Stamets himself wears a hat made from amadou, a tangible connection to this ancient technology.

How Can Fungi Help Remediate Pollutants and Restore Ecosystems?

Beyond food and medicine, fungi offer solutions for ecosystem restoration and pollution cleanup. Stamets mentions the "Life Box," an innovation designed to help re-establish forests and clean up contaminated sites. While the full details are not elaborated in this excerpt, the principle is clear: mycelial networks are capable of breaking down pollutants and toxins that would otherwise persist in soil and water.

This remediation capacity flows from the mycelium's role in decomposition cycles. Fungi are nature's primary decomposers—they break down dead organic matter and, in doing so, also consume certain synthetic pollutants. By deploying fungal cultures strategically, humans can accelerate the detoxification of contaminated land. Stamets emphasizes that one practical first step is straightforward: don't throw away your wood. Leaving dead wood to decompose in place supports the mycelial networks that restore soil health and sequester carbon.

What Is the Connection Between Human DNA and Fungal Evolution?

Stamets touches on a profound evolutionary fact: humans are more closely related genetically to fungi than to plants. This biological kinship suggests that understanding fungi is, in a sense, understanding ourselves. The DNA architecture differs—human DNA is enclosed in a nucleus, while fungal DNA is not—yet the genetic overlap is substantial. This closeness may explain why so many fungal compounds interact beneficially with human physiology and immunity. It is not coincidental that fungi produce medicines effective in human bodies; the relationship is evolutionary, rooted in shared metabolic pathways.

What Does Stamets' Worldview Suggest About Humanity's Role in Nature?

Stamets frames his work not from a secular scientific stance alone but from a conviction that the interconnectedness of nature is "not an accident." He grew up in a highly religious household and sees the mycelial networks and the complexity of life as expressions of intelligence or design embedded in natural systems. This perspective informs his urgency: if the natural world is deeply organized and purposeful, then dismantling it carelessly is not merely wasteful—it is a denial of the very intelligence that sustains us.

The solution, in Stamets' view, lies in recognizing fungi as allies rather than curiosities. By understanding mycelial networks as biological infrastructure, by protecting old-growth forests that harbor rare species like Agarikon, and by deploying fungal remediation techniques in polluted regions, humanity can shift from being a destructive force to a partner in ecosystem restoration. Biodiversity, then, is not a luxury or an aesthetic concern—it is the security system upon which human survival depends.

Where to Go From Here

If Stamets' argument resonates, the implications are clear: study fungi seriously, support the protection of old-growth forests, and recognize soil health as a national priority comparable to food security or defense infrastructure. Stamets' books, including Mycelium Running: How Mushrooms Can Help Save the World, offer deeper exploration of fungal applications. His work with organizations like the North American Mycological Association has also opened mycology to amateurs, democratizing knowledge that was once confined to specialists. For those interested in practical action, learning to identify edible and medicinal fungi in your region, composting to support local mycelial networks, and advocating for old-growth forest protection are tangible steps toward the biodiversity resilience Stamets describes as essential to our collective future.