Entangled Life

The summary

A mushroom is just the fruit. The organism itself is a web — mycelium, a mesh of fine filaments called hyphae that threads through soil, wood, and the bodies of other creatures. Merlin Sheldrake’s argument is that fungi quietly demolish one of our most basic assumptions: that life comes packaged as separate, self-contained individuals. Mycelium has no brain, no center, no body plan, yet it solves problems, trades goods, and manipulates animals. Follow the fungi and the neat boundary around “an organism” starts to dissolve.

Intelligence without a brain

“Mycelium is a body without a body plan,” Sheldrake writes. It’s a decentralized network that navigates complex environments with no central controller. In experiments, a wood-rotting fungus laid out among scattered blocks of wood found the most efficient path between them — a computation with no computer. These networks coordinate across large distances using fast signals, probably electrical, letting a fungus respond to its world in real time.

That reframes what a living thing even is. A mycelial network is a map of the fungus’s recent history, a reminder that organisms are processes rather than objects. The “you” of five years ago was built from different atoms than today’s you. As William Bateson, who coined the word “genetics,” put it, “We commonly think of animals and plants as matter, but they are really systems through which matter is continually passing.”

The underground market that built the world

Around 500 million years ago, the algal ancestors of plants hauled themselves onto land with no roots to pull water and minerals from bare rock. Mycorrhizal fungi became their root systems and did that job for tens of millions of years. Plants fed the fungi sugars from photosynthesis; the fungi returned water and minerals. The partnership set off an explosion of plant life that dropped atmospheric carbon dioxide by 90 percent and cooled the planet. More than 90 percent of plant species still depend on these fungal relationships today.

The exchange behaves like a market. Plants reward the more cooperative fungal partners with more sugar, while fungi shuttle resources across their network to “sell high” wherever nutrients are scarce. These mycorrhizal webs — the “wood wide web” — physically link plants, sometimes across different species, moving carbon, nitrogen, phosphorus, and water from the resource-rich to the struggling. They even carry warnings: when insects attack one plant, connected neighbors switch on their own chemical defenses without any direct contact with the pest. Modern farming breaks this open system. Tilling, chemical fertilizers, and fungicides thin out soil fungi, leaving crops more dependent on inputs and more fragile in drought and disease.

Chemical puppeteers

Fungi manipulate other organisms mostly through scent and chemistry. Truffles, the underground fruiting bodies of certain fungi, can’t launch their spores into the air, so they produce alluring scents that get animals to dig them up and eat them, spreading the spores instead. Others are far more sinister. The “zombie fungus” Ophiocordyceps unilateralis infects carpenter ants, seizes control of their muscles with chemicals, and drives them to leave the nest, climb a plant, and clamp their jaws down before dying — after which the fungus fruits from the ant’s head and rains spores on the colony below. The ant’s brain stays intact; this is chemical puppetry, not mind control.

Magic mushrooms run a subtler chemistry on us. Psilocybin stimulates serotonin receptors and quiets the brain’s default mode network, the circuitry tied to ego and self-reflection, which can dissolve the sense of a separate self. Clinical trials show a single dose producing lasting drops in severe depression and anxiety, especially in terminally ill patients — apparently not by pushing biochemical buttons but by opening people to new ways of thinking about their lives. The compound likely evolved as a defense against insects; its modern fame traces to Gordon Wasson’s 1957 article “Seeking the Magic Mushroom.”

We are all lichens

A lichen isn’t one thing but a partnership — a fungus joined with algae or bacteria — and that symbiosis lets lichens survive where almost nothing else can, including radiation, extreme temperatures, and the vacuum of space. For Sheldrake they’re the clearest lesson of the book: “There have never been individuals… We are all lichens.” What we call a single organism is usually a collaboration, a process through which matter keeps passing rather than a fixed, bounded thing.

Fungi as tools

Fungi also rewrote the planet’s chemistry, and may help us fix it. During the Carboniferous, wood didn’t rot because no fungus could yet break down lignin, so unrotted plant matter piled up and became coal. Now fungi are master decomposers, and we’re learning to point that talent at our messes: mycoremediation uses fungi to break down crude oil, pesticides, explosives, and plastics, while mycofabrication grows mycelium into packaging, leather-like textiles, and building materials. Paul Stamets has shown that extracts from certain wood-rotting fungi sharply cut deadly viruses in honeybees, a possible lever against colony collapse. And yeast, another fungus, helped anchor the Neolithic shift to settled farming through baking and brewing — so much so that “you might argue, yeasts have domesticated us.” Even our taste for alcohol may be fungal in origin: the drunken monkey hypothesis says we followed the scent of fermenting fruit long before we brewed anything.

The bottom line

Fungi are networked, brainless problem-solvers that made land life possible and blur the line between the individual and the ecosystem — proof that the living world is less solid and more entangled than it looks. Read this if you want the ground under your feet, and your sense of where “you” ends, to feel a lot stranger.