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

by Merlin Sheldrake

While I crouched for weeks scraping mud into small tubes, toucans croaked, howler monkeys roared, lianas tangled, and anteaters licked. Microbial lives, especially those buried in soil, were not accessible like the bristling charismatic aboveground world of the large. Really, to make my findings vivid, to allow them to build and contribute to a general understanding, imagination was required. There was no way around it. In scientific circles imagination usually goes by the name of speculation and is treated with some suspicion; in publications it is usually served up with a mandatory health warning. Part of writing up research is scrubbing it clean of the flights of fancy, idle play, and the thousand trials and errors that give rise to even the smallest of findings. Not everyone who reads a study wants to push their way through the fuss. Besides, scientists have to appear credible. Sneak backstage and one might not find people at their most presentable. Even backstage, in the most nocturnal musings I shared with colleagues, it was unusual to get into the details of how we had imagined—accidentally or deliberately—the organisms we studied, whether fish, bromeliad, liana, fungus, or bacterium. There was something embarrassing about admitting that the tangle of our unfounded conjectures, fantasies, and metaphors might have helped shape our research. Regardless, imagination forms part of the everyday business of inquiring. Science isn’t an exercise in cold-blooded rationality....

Anthropomorphism is usually thought of as an illusion that arises like a blister in soft human minds: untrained, undisciplined, unhardened. There are good reasons for this: When we humanize the world, we may prevent ourselves from understanding the lives of other organisms on their own terms. But are there things this stance might lead us to pass over—or forget to notice? The biologist Robin Wall Kimmerer, a member of the Citizen Potawatomi Nation, observes that the indigenous Potawatomi language is rich in verb forms that attribute aliveness to the more-than-human world. The word for “hill,” for example, is a verb: to be a hill. Hills are always in the process of hilling, they are actively being hills. Equipped with this “grammar of animacy,” it is possible to talk about the life of other organisms without either reducing them to an “it” or borrowing concepts traditionally reserved for humans. By contrast, in English, writes Kimmerer, there is no way to recognize the “simple existence of another living being.” If you’re not a human subject, by default you’re an inanimate object: an “it,” a “mere thing.” If you repurpose a human concept to help make sense of the life of a nonhuman organism, you’ve tumbled into the trap of anthropomorphism. Use “it,” and you’ve objectified the organism and fallen into a different kind of trap. Biological realities are never black-and-white. Why should the stories and metaphors we use to make sense of the world—our investigative tools—be so?...

I asked Boddy what aspects of mycelial lives remain most mysterious. “Ah…that’s a good question.” She faltered. “I really don’t know. There are just so many things. How do mycelial fungi work as networks? How do they sense their environment? How do they send messages back to other parts of themselves? How are those signals then integrated? These are all huge questions which hardly anyone seems to be thinking about. Yet understanding these things is crucial to understanding how fungi do almost everything that they do.

Fungi use a variety of approaches to tweak the biochemical dials that regulate their hosts’ behavior. Some use immunosuppressants to override the insects’ defensive responses. Two such compounds have found their way into mainstream medicine for these very reasons. Cyclosporine is an immunosuppressant drug that makes organ transplants possible. Myriocine has become the blockbuster multiple sclerosis drug fingolimod and was originally extracted from fungus-infested wasps that are eaten in parts of China as a nostrum for eternal youth.

Different species of mycorrhizal fungus might cause a basil leaf to taste different or a strawberry plant to produce more delicious-looking berries. But how? Are some fungal partners “better” than others? Are some plant partners “better” than others? Can plants and fungi tell the difference between alternative partners? Decades have elapsed since Rayner’s remark, but we are only just beginning to understand the intricate behaviors that maintain a symbiotic balance between plants and mycorrhizal fungi.

What about effects of fungi on coffee trees?

If humans have unthinkingly bred varieties of crops that form dysfunctional symbioses with fungi, surely we can turn around and breed crops that make high-functioning symbiotic partners.

PRECISELY WHAT IS passing between plants through fungal networks is a thorny question for all researchers investigating wood wide webs. It is a lack of knowledge that leads to some conceptual impasses. For instance, without knowing how information passes between plants, it’s impossible to know whether donor plants actively “send” a warning message, or whether receiver plants simply eavesdrop on their neighbor’s stress. In the eavesdropping scenario, there is nothing that we might recognize as deliberate behavior on the part of the sender. As Kiers explained, “If a tree gets attacked by an insect then of course it’s going to scream in its language: It will produce some sort of chemical to get ready for the attack.” These chemicals could easily spill over from one plant into another through the network. Nothing is actively sent. The receiver plant just happens to notice. Johnson uses the same analogy. If we hear someone screaming, it doesn’t mean they are screaming in order to warn us of something. Sure, a scream may cause us to change our behavior, but it doesn’t imply any intention on the part of the screamer. “You’re just eavesdropping on their response to a particular situation.” It may seem like splitting hairs, but a lot turns on which way we read the interaction.

AROUND THE WORLD, the idea that fungi can be used to build things as well as break them down is starting to catch on. A material made from the outer layers of portabello mushrooms shows promise in replacing graphite in lithium batteries. The mycelium of some species makes an effective skin substitute, used by surgeons to help wounds to heal. And in the United States, a company called Ecovative Design is growing building materials out of mycelium. I went to visit Ecovative’s research and manufacturing facility in an industrial park in upstate New York. Stepping into the lobby, I found myself surrounded by mycelial products. There were boards, bricks, acoustic tiles, and molded packaging for wine bottles.

To this day, fungi slip around the systems of classification we build for them. The Linnaean system of taxonomy was designed for animals and plants, and doesn’t easily cope with fungi, lichens, or bacteria. A single species of fungus can grow into forms that bear no resemblance to each other whatsoever. Many species have no distinctive characteristics that can be used to define their identity. Advances in gene sequencing make it possible to order fungi into groups that share an evolutionary history, rather than groups based on physical traits. However, deciding where one species starts and another stops based on genetic data presents as many problems as it solves. Within the mycelium of a single fungal “individual” there can exist multiple genomes. Within the DNA extracted from a single pinch of dust, there might be tens of thousands of unique genetic signatures, but no way to assign them to known fungal groups. In 2013, in a paper called “Against the naming of fungi,” the mycologist Nicholas Money went so far as to suggest that the concept of fungal species should be abandoned altogether.

The first submarine, Turtle, developed during the American Revolutionary War, used glowing fungi to illuminate its depth gauge. English coal miners in the nineteenth century reported fungus on pit props that cast enough light to see their hands by.