We've been eating fungi, curing ourselves with them, worshiping and fearing them for millennia — and yet the fungal kingdom remains the most unknown and misunderstood of the great groups of life. Here are the facts that, once you know them, you can't unsee.
FungiFacts — Issue #1
#1 — The world's largest living organism is a fungus.
In Oregon's Malheur National Forest, USA, a specimen of Armillaria ostoyae lives, covering more than 8.9 km² of forest floor and estimated to be between 8,000 and 8,600 years old. It is genetically a single individual. For reference: New York's Central Park covers 3.4 km². This fungus, if you walked at a normal pace, would take you more than 3 hours to cross.
#2 — Without fungi, forests would have disappeared millions of years ago.
During the Carboniferous Period (about 350-300 million years ago), trees had evolved lignin — the compound that makes wood resistant — but no organism had yet evolved the ability to decompose it. Trees died, fell, and accumulated for millions of years without decomposing. This is literally the origin of the coal we use today as fossil fuel. When white rot fungi evolved the enzymes to decompose lignin, the carbon cycle was restored. Fungi saved the planet from drowning in dead wood.
#3 — Fungi "invented" agriculture 50 million years before humans.
Leaf-cutter ants have been cultivating a specific fungus of the genus Leucoagaricus for about 50 million years to feed their colonies. They cultivate it in underground chambers, fertilize it with crushed leaves, eliminate other competing fungi using natural antibiotics they secrete, and select varieties over generations. It is sophisticated agriculture — 50 million years before Homo sapiens appeared.
#4 — Beer, wine, bread, and cheese exist thanks to fungi.
Saccharomyces cerevisiae — brewer's yeast — is a single-celled fungus that has been fermenting human civilization's sugars for at least 13,000 years (the oldest archaeological evidence is from a brewery in a cave in Israel). Without this species of fungus, there would be no beer, wine, sake, leavened bread, or a good part of the modern pharmaceutical industry. The insulin used by millions of diabetics is produced using genetically modified S. cerevisiae.
#5 — Alexander Fleming discovered penicillin due to a fungus contaminating his Petri dish.
In 1928, Fleming returned from vacation to his lab in London and found that a Staphylococcus culture plate had been contaminated by a fungus (Penicillium notatum). Around the fungus, the bacteria had died. Instead of discarding the "ruined" plate, Fleming studied it. The compound the fungus produced to defend itself turned out to be the most important antibiotic in human history. Penicillin and antibiotics derived from fungi are among the drugs that have saved the most lives in history.
#6 — Plants colonized land thanks to fungi.
Around 450 million years ago, the first land plants did not have roots capable of extracting nutrients from the rocky soil. What they did have were fungi. The oldest fossils of land plants show structures of fungal mycelium integrated into their tissues — fungi that acted as prosthetic roots for plants that had not yet evolved their own. Without this symbiosis, the colonization of land by plants — and everything that followed: insects, amphibians, reptiles, mammals, humans — would not have happened in the same way.
#7 — Fungal spores travel in the stratosphere.
The spores of many fungi are so light (between 1 and 100 micrometers) that the convection current generated by the fungus itself when releasing water vapor actively lifts them into the atmosphere. Viable fungal spores have been found at altitudes of up to 25 km — in the stratosphere. A single specimen of Calvatia gigantea (the giant puffball mushroom) can produce 7 trillion spores. If all germinated, they would cover the entire planet.
#8 — Fungi are genetically closer to animals than to plants.
Fungi and animals share a more recent common ancestor than fungi and plants. The cell walls of fungi are made of chitin — the same compound that forms the exoskeleton of insects and crustaceans — not cellulose like plants. Fungi also store carbohydrates as glycogen — like animals — not as starch. When you eat a mushroom, you are eating something biologically more similar to yourself than to a carrot.
#9 — A fungus can grow 2 cm per hour.
Coprinus comatus (shaggy ink cap) mushrooms can emerge from the ground and grow up to 2 cm per hour — fast enough to be visible without time-lapse. The mechanism: instead of actively dividing cells (as most organisms do to grow), fungi inflate their existing cells with water by osmotic pressure. It's like inflating balloons instead of building more bricks.
#10 — Cyclosporine — the drug that makes organ transplants possible — comes from a fungus.
Tolypocladium inflatum is a Norwegian soil fungus from which cyclosporine was isolated in 1969. This compound selectively suppresses the immune system so that it does not reject transplanted organs. Without this fungus, kidney, liver, heart, and lung transplants as we know them today would not be possible. Each year, about 170,000 organ transplants are performed worldwide, made possible by the immunosuppression that this fungal compound inaugurated.
#11 — Fermentation yeasts controlled the history of world trade.
For centuries, brewers and bakers didn't know they were working with living organisms. Yeast was passed down from generation to generation in unwashed wooden equipment — without understanding why it worked. Louis Pasteur demonstrated in 1857 that fermentation was caused by living microorganisms, not by purely chemical processes. It was one of the most important discoveries in the history of science — and it came from the study of the French brewing industry.
#12 — Fungi can clean up oil-contaminated soils.
Mycoremediation is the use of fungi to break down environmental contaminants. Paul Stamets documented experiments where Pleurotus ostreatus (oyster mushroom) mycelium decomposed petroleum hydrocarbons in contaminated soil in 6 weeks, transforming black, toxic soil into fertile, plant-supporting earth. Fungi produce enzymes (laccases, peroxidases) that can break down complex molecular structures that conventional chemistry cannot — including plastics.
#13 — Roquefort and Camembert cheese are made with Penicillium fungi.
The same genera that produce antibiotics flavor the world's most famous blue cheeses. Penicillium roqueforti creates the blue-green veins of Roquefort, Gorgonzola, and Stilton. Penicillium camemberti forms the white rind of Camembert and Brie. Fungi are not just medicine — they have been fine gastronomy for centuries.
#14 — Mycelium material can replace polystyrene plastic.
Companies like Ecovative Design grow Ganoderma mycelium on agricultural waste (straw, rice hulls) in molds. The result after 5-7 days: a strong, lightweight, and 100% biodegradable material that has the same cushioning properties as expanded polystyrene — without the 500 years of degradation. IKEA, Dell, and Adidas already use it in packaging.
#15 — The Wood Wide Web of the forest was discovered by a Canadian researcher in 1997.
Suzanne Simard published the first experimental evidence in Nature that forest trees transfer carbon to each other through mycorrhizal mycelial networks. What she found: adult trees preferentially share carbon with their neighboring seedlings, acting as "mother nodes" in a forest communication network. The phrase "Wood Wide Web" emerged from that article. In 2021, Simard published Finding the Mother Tree — one of the most widely read scientific memoirs of the last decade.
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