Entangled Life: How Fungi Make Our Worlds, Change Our Minds & Shape Our Futures

by Merlin Sheldrake

Lefevre told me about the theory that manna—the providential food that sustained the Israelites during their passage through the desert—was in fact the desert truffle, a delicacy that erupts without warning from arid ground across much of the Middle East.

If the fungus discovers something to eat, it reinforces the links that connect it with the food and prunes back the links that don’t lead anywhere. One can think of it in terms of natural selection. Mycelium overproduces links.

The difference between animals and fungi is simple: Animals put food in their bodies, whereas fungi put their bodies in the food.

“We commonly think of animals and plants as matter, but they are really systems through which matter is continually passing.” When we see an organism, from a fungus to a pine tree, we catch a single moment in its continual development.

If we could plug into mycelial networks and interpret the signals they use to process information, we could learn more about what was happening in an ecosystem. Fungi could report changes in soil quality, water purity, pollution, or any other features of the environment that they are sensitive to.

In fact, this wording doesn’t get it quite right. The ancestors of today’s plants didn’t acquire a bacterium with the ability to photosynthesize; they emerged from the combination of organisms that could photosynthesize with organisms that couldn’t.

LICHENS ARE PLACES where an organism unravels into an ecosystem and where an ecosystem congeals into an organism.

Once infected by the fungus, ants are stripped of their instinctive fear of heights, leave the relative safety of their nests, and climb up the nearest plant—a syndrome known as “summit disease.” In due course the fungus forces the ant to clamp its jaws around the plant in a “death grip.” Mycelium grows from the ant’s feet and stitches them to the plant’s surface. The fungus then digests the ant’s body and sprouts a stalk out of its head, from which spores shower down on ants passing below. If the spores miss their targets, they produce secondary sticky spores that extend outward on threads that act like trip wires.

Ophiocordyceps is closely related to the ergot fungi, from which the Swiss chemist Albert Hofmann originally isolated the compounds used to make LSD,

“the psilocybin-containing mushrooms were encountered, consumed and deified. Language, poetry, ritual, and thought emerged from the darkness of the hominid mind.”

horizontal gene transfer is the process by which genes and the characteristics they underpin move between organisms without the need to have sex and produce offspring.

Mycorrhizal hyphae are fifty times finer than the finest roots and can exceed the length of a plant’s roots by as much as a hundred times.

Intrigued by these questions, and having read Thomas Piketty’s work on wealth inequality in human societies, Kiers began thinking about the role of inequality within fungal networks. She and her team exposed a single mycorrhizal fungus to an unequal supply of phosphorus. One part of the mycelium had access to a big patch of phosphorus. Another part had access to a small patch. She was interested in how this would affect the fungus’s trading decisions in different parts of the same network. Some recognizable patterns emerged. In parts of a mycelial network where phosphorus was scarce, the plant paid a higher “price,” supplying more carbon to the fungus for every unit of phosphorus it received. Where phosphorus was more readily available, the fungus received a less favorable “exchange rate.” The “price” of phosphorus seemed to be governed by the familiar dynamics of supply and demand.

I feel a similar sense of vertigo when I think about the complexity of mycorrhizal relationships—kilometers of entangled life—jostling beneath my feet.

Researchers swapped the fungal endophytes that lived in each type of grass so that coastal grasses were grown with hot geothermal fungi and vice versa. The grasses’ ability to survive in each habitat switched.

Why would plants give resources to a fungus that goes on to give them to a neighboring plant—a potential competitor? At first glance it looks like altruism. Evolutionary theory doesn’t cope well with altruism because altruistic behavior benefits the receiver at the cost of the donor. If a plant donor assists a competitor at a cost to itself, its genes are less likely to make it into the next generation. If the altruist’s genes don’t make it into the next generation, the altruistic behavior will soon be weeded out.

One species of mycorrhizal fungus, the thick-footed morel (Morchella crassipes), actually farms the bacteria that live within its networks: The fungus “plants” bacterial populations, then cultivates, harvests, and consumes them. There is a division of labor across the network, with some parts of the fungus responsible for food production and some for consumption.

when stress signals pass from a sick plant to a healthy plant, it is the fungus that stands to benefit from keeping the healthy plant alive.

Beiler’s maps are striking. Fungal networks sprawl over tens of meters, but trees are not linked evenly. Young trees have few connections, and older trees have many. The most well-connected tree is linked to forty-seven other trees and would have been linked to two hundred fifty others if the plot had been larger than it was. If one uses a finger to jump from tree to tree across the network—which is, of course, a plant-centric thing to do—one doesn’t trickle through the forest evenly. One skips across the network through a small number of well-connected older trees. Via these “hubs,” it’s possible to get to any other tree in no more than three steps.

After Hiroshima was destroyed by an atomic bomb, it is reported that the first living thing to emerge from the devastation was a matsutake mushroom.

Fungi isolated from a contaminated environment may have already learned how to digest a given pollutant and, as locals, be able to remediate a problem and thrive. This was the approach used by a team of researchers in Pakistan who screened soil from a city landfill site in Islamabad and found a novel fungal strain that could degrade polyurethane plastic.

Confronted with the problem of how to access the energy in plant matter, Macrotermes termites have been cultivating huge quantities of white rot fungi in purpose-built production facilities for thirty million years. Macrotermes and Termitomyces have lived with one another for so long that neither can survive without the other.

was either for bread or for beer that humans started to give up their nomadic lifestyles and settle into sedentary societies

Ancient Sumerians—who left written beer recipes dating back five thousand years—worshipped a goddess of fermentation, Ninkasi. In The Egyptian Book of the Dead, prayers are addressed to “givers of bread and beer.” Among the Ch’orti’ people in South America, the onset of fermentation was understood as “the birth of the good spirit.” The ancient Greeks had Dionysus—the god of wine, winemaking, madness, drunkenness, and domesticated fruit in general—a personification of the power of alcohol both to forge and corrode human cultural categories.

Fermentation is domesticated decomposition—rot rehoused.

Many of the historical brews were fun to drink. The meads brought on laughter. The gruit ales made people talkative. Dr. Butler’s ale induced a peculiar golden heaviness. Some were bottled havoc. Whatever their effect, I was fascinated by the process of brewing a historical text into being. Old brewing recipes are records of how yeasts have etched themselves into human lives and minds over the last few hundred years. In all the pages of these books, yeasts are a silent companion, an invisible participant in human culture. Ultimately, these recipes were stories that made sense of how substances decomposed. They reminded me that it matters what stories we use to make sense of the world. The story you hear about grain determines whether you end up with bread or beer. The story you hear about milk determines whether you end up with yogurt or cheese. The story you hear about apples determines whether you end up with sauce or cider.

The ability to metabolize alcohol, they speculate, played a crucial role in the ability of primates to make a living on the forest floor by opening up a new dietary niche: overripe, fermented fruit that had fallen from trees.

I was intoxicated with a story, comforted by it, constrained by it, dissolved in it, made senseless by it, weighed down by it. I called the cider Gravity and lay heavy and reeling under the influence of yeast’s prodigious metabolism.