Mushroom Thoughts on Existential Risk. No Magic.

written by Carla Zoe Cremer, illustrated by Magdalena Adomeit

Merlin Sheldrake’s book Entangled Life, has much to teach us about existential resilience, conservation and the climate crisis. The world of fungi guards the secrets of longterm survival. But the principles which underlie their resilience extends much beyond the kingdom of fungi into lessons about the persistence of life.

In Sum

The ubiquity of symbiosis questions whether the prevention of our extinction can be accomplished by saving the human species alone. Avoiding extinction and existential risk appears inextricably entangled with the survival of a sizable number of other species, many of which we have yet to identify.

Fungi stretches the category ‘technology’ in my mind. Sheldrake lists a surprisingly large range of mycelium-based applications which play a role bio-sensing, factory-farming or construction. Their metabolic functions are promising technology. We should study what we already have and use it well.

At last, fungi exemplify a trade-off between yield and resilience, which questions whether the apparent arch of progress we associate with modern industry and agriculture is real – particularly from a longtermist perspective.

I present some initial thoughts on the relationship between fungi and existential risk. This is not my speciality. I chose to describe my naïve impressions frankly, but I intend to keep an openness to changing mind. My aim is not to present water-tight arguments, but instead provide a taste of a perspective. Try to indulge in the fuzziness.

I collected some facts about fungi from Sheldrake’s book, but I encourage you to read the book in full. It contains extensive references to primary literature in endnotes. If you are familiar with what fungi are and what they can do for us, feel free to skip to the last section, in which I relate those facts to existential risk.


Fungi are eukaryotes. Their biomolecular structure is closer to animals than plants. They are ubiquitous. You will find fungi in most places on the planet, including yourself. Constructed of hyphae – elongated tubes which form mycelium networks – they lack a central nervous system. And yet, they are mysteriously able to make sophisticated decisions across tough trade-offs, directions and survival strategies. In exploration of their territory, the tips of mycelia will grow outwards in a spherical from. One of many tips, upon having discovered a desirable destination, will redirect growth of the whole networks using electric pulses (possibly analogous to action potentials in brains). How exactly decisions are made, and coordination is achieved, we do not yet know.

90% of fungi species have not yet been classified. Estimates on the existing number of species range from 2.2-3.8 Million, which could be 10 times more than the number of plant species.

Fungi appear to be able to digest nearly everything (raw oils, TNT, stone, radioactive material…). If they can’t directly digest one material, you can teach them. Some release their spores explosively, reaching a speed of 100 km/​h, making them one of the fastest organisms on the plant. Their spores make up the largest fraction of living matter in the air (50 Million tonnes per year). These spore loads affect the weather.

If you’d measure mycorrhiza hyphae in the first 10 centimetres below ground, they would cover the length of half of our galaxy (4.5 x10^17 kilometres). The largest living organism on this planet is a fungus (Armillaria in Oregon) – this specimen is 8000 years old.

For millions of years, fungi were the only large organisms. These prototaxites were meters-high, pillar-like ecosystems. Ca. 400 million years ago, plants were enabled to move onto land and grow into trees, due to mycorrhiza (fungi-roots), which granted them better access to vital phosphor.

According to computational models, the symbiotic efficiency between plants and fungi alone, can result in changes to the earth’s climate. CO2 and oxygen levels in the atmosphere were dependent on the efficiency of the trade between plants and fungi, leading to changes in global temperature (e.g. 300 Million years ago). Humans, who live in a specific temperature range, are reliant on such regulation.

We’re only beginning to understand the role of fungi in forests. The speed of forest movement depends in parts on the efficiency of their relationship to mycorrhiza. Fungi drive evolutionary variety and allow organic growth in areas that would otherwise be too hostile. The ecosystem services we derive from forests, depend vitally on the health of fungi-infused soil. Today, more than 90% of plants rely on mycorrhiza for their nutrients and information flows. Some plants cannot survive without them, which questions the very idea of separable species. In essence, fungi build trading networks for organisms in the forest, providing fertile ground for studying inequality, cooperation or defection in natural markets.

Impressive Applications of Fungi

Medication: The genus homo has long been using fungi for medicinal purposes. Most recently, humans started using penicillin, cyclosporin (used for organ transplants) and psilocybin. How many medications remain undiscovered, considering how many fungi species are still unknown?

Problem solving: A number of studies examine how fungi are able to find the most efficient path through a complex environment of obstacles. They will for example, naturally replicate the road network in Tokyo or ancient Rome.

Resilience and Space-travel: Fungi have survived all five mass extinction events. Lichen – roughly a symbiotic union between fungi and algae – are being tested as a promising candidate for surviving space conditions. Astrobiologists found them to be resistant against 6 kilograys of radiation (12.000x as much as the lethal dose for humans). At 12 kilogray, they still do photosynthesis. Dip them in liquid nitrogen of −195 degrees Celsius—nothing happens. They are found in adverse earth-bound conditions such as deserts, volcanic springs, or underneath tonnes of ice sheets, as well as kilometres deep underneath the earth’s surface in the midst of immense heat and pressure. Some of them are thousands of years old. I’d be surprised if we cannot learn a thing or two about resilience from fungi.

Both lichen and humans are an excellent example of the incredible resilience and extraordinary intelligence that can emerge from symbiotic unions.

Lichen are a mini ecosystem – a process of symbiotic, dynamic interaction between organisms who each contribute functions that the others are lacking. The survival of each depends so vitally on others, that they blur the boundaries of the concept species. While each of course is identified by their unique DNA, the ability to stay alive is ensured only through the existence of a symbiotic partner: a full set of foreign DNA.

The term holobiont tries to capture this: a cooperative assembly of separate genetic entities that form an otherwise impossible organism. Humans of course are holobionts or as Sheldrake calls us: symborgs. Both lichen and humans are an excellent example of the incredible resilience and extraordinary intelligence that can emerge from symbiotic unions.

Conservation and ecosystem services: Fungi can drastically reduce the rate of bee death. They can absorb toxins in soil or water. Mycelium sheaths will filter water from heavy metals.

They can digest toxic waste or other materials that we have no use for (which means we don’t have to burn it and pollute the air), including cigarette buds (of which we accumulate 750.000 tonnes per year), diapers (ca 15% of waste in cities), nerve gas, pesticides, TNT, synthetic colours, plastics, synthetic hormones and antibiotics, oil spills, and radioactive materials (so-called ‘radiotrophs’ thrive off radioactivity). More interestingly, if the conditions are right, fungi can learn and re-activate dormant genes, to digest materials which they usually do not digest.

The company CoRenewal uses fungi to eliminate toxins associated with oil extraction. In California, we fight the toxic sewage resulting from wild-fires in 2017 with mycelia-pipes.

Biofabrication: Fungi can be used to construct building materials, fabrics or leather. The company Ecovative has a mycelium factory for ecological packaging, furniture and bricks. NASA wants to use it to build and furnish houses on the moon and DARPA want to make self-repairing fungi-buildings. The research project FUNGAR has even more ambitious plans.

Though human extinction surely is the loss of our DNA, we will need to think beyond our gene code to prevent it.

Bio-sensing: Certain fungi such as phycomyces are highly sensitive to environmental conditions (toxins, temperature, humidity…) and could serve as a sensor to signal maladaptive changes or detrimental waste products in the environment.

Mycelium-computing: Electrical communication in mycelium networks can be used to build circuits. Prototypes, mostly for bio-sensing, are in development.

Medicinal Psychedelics: LDS and psilocybin are derived from fungi and have a long tradition of being digested by humans. They are now being investigated for their therapeutic effects on mental illness.

Fungi and Existential Risk

Surviving Alone

Human survival and flourishing never relied on human DNA alone. Though human extinction surely is the loss of our DNA, we will need to think beyond our gene code to prevent it. The number of microbes we carry (ca. 40 trillion) plausibly exceeds the number of our human cells. Our ecosystem of microbes is integral to our minds, immune function, cell function and growth. There are an unfathomable number of individuals that make us the individual we think we are. Bacteria can further host viruses, and they too affect the function of bacteria in our body.

As I considered how exactly our life form survives – which is as a holobiont and symborg – I became increasingly unsure about what other species we may need to save, if we wanted to save ourselves. Without which organisms would our survival chances plummet? We’d be wise to protect constituents of our life form whose function we do not yet understand. These functions may be more vital to us than we now recognise.

Life indispensably relies on symbiosis. Certain plants, such as Voyria, have ceased to perform photosynthesis: they cannot survive without fungi that deliver essential nutrients. Evolution does not “repair” the insufficient functionality of each organism – instead, organisms find symbiotic partners who fill their metabolic gaps. Life is distributed across species, not detained by each one of them.

The anthropologists Myers and Hustak use the term involution to describe this approach to overcoming biological limitations. Organisms drive (to survive) into the life, territory and metabolism of other, existing organisms, rather than to compete or identify niches which are not yet occupied.

Our knowledge of how exactly new shapes emerge and persist is still humiliatingly incomplete. Sheldrake calls it dark life.

Symbiosis is not nice. It is not altruistic, feminine or naïve. Organic fusions pursue an amoral strategy. Materialism underpins each union. Evolution is the game structure and symbiosis does not preclude competition to exist alongside it. But biology simply does not play a zero-sum game. It is rarely the rational choice to fend for yourself as a species on this planet.

It was a symbiotic relationship between algae and fungi that allowed plants to move on land. This transition enabled everything we now value. Symbiosis prompts the emergence of new life forms. Our knowledge of how exactly new shapes emerge and persist is still humiliatingly incomplete. Sheldrake calls it dark life.

Over the long run, humans could witness how new, unimaginable and precious life forms emerge. Symbiosis will play a role. It seems short-sightedly unwise to gamble with the extinction of current species, species which could be the foundation of a radically better and more spacious future life.

Anti-Fragility

Mycelium is one of the oldest (2.4 bn yrs) multicellular life forms ever found. Clearly fungi are rather robust. Fungi are adaptable and flexible in form and nutrient requirements. A significant fraction of their resilience can be attributed to their promiscuity in building symbiotic relationship with other organisms. The least we can do is to check whether we can learn lessons about anti-fragility from fungi and see whether they may be applicable to our own species. It would be strategically ill-informed to leave the research on fungal functions untouched and under-funded.

Permanence is fragile.

Sheldrake thinks of long-lived life forms as processes, rather than static entities. Therein lies a crucial lesson: the difference between security and anti-fragility. Permanence is fragile. We cannot afford to desire stability, to fulfil our need to control and secure. Trying to stay the same, in a dynamic, conjunctional environment is wasteful and risky. We should instead balance our form and strengthen our resilience. Humanity too is a process. We should learn to adapt to and absorb shocks.

Collecting Technology

I encounter much optimism about global biodiversity loss. Bioengineering, the optimist argues, will let us revive (de-extinct) species, if we retrospectively deem them useful. I wish I was convinced. But instead, this appears overconfident and rushed.

I have my doubts about the sophistication of our bioengineering abilities. Sheldrake describes how the truffle industry has all but failed to technologically control the yield of truffle. Incentives are not amiss: the truffle industry is ripe with murders and robberies due to the amount of money that can be made with say, a well-trained truffle dog. But the interactions between organisms and the environmental conditions in the soil are (for now) too complex to replicate in laboratory conditions. The object of desire, and in this case its aroma, is inextricable dependent on the chemical and atmospheric conditions in which the truffle grows. The species of interest is not separable from its home ecosystem.

Apart from my scepticism that we can replicate and revive whole ecosystems and their species in the near future, it strikes me irrational at best to neglect a perfectly well-functioning machinery to the point of decay, only to build a new one from scratch.

Where is the efficiency in that?

Fungi could reduce pollution, atomic waste, bio-diversity loss, toxins, mental illness… they could contribute to resilient agriculture, space travel, bio-engineered materials…the list goes on and is yet incomplete. ‘Dark Life’ is ripe with fruitful tech: picking it is a matter of choice and funding.

Imagine if little pieces of artificial intelligence were lying around on the ground. A little concept formation here, a little continual learning and causal cognition there…why would we not pick it up? We may not need AI as urgently as we think. Fungal metabolic functions can already solve a number of our problems. Our conception of technology is inconsistent. We describe the human brain as complex computer and our bodies as sophisticated machines. The logical conclusion is that non-human life forms too are little machines. We should protect their functionality with the same eagerness as we are aggressively pursuing artificial intelligence to be built and solve all our problems.

Indeed, fungal applications, will in most cases likely integrate more safely with our civilisation than an artificial machinery we build from scratch. Many good solutions will not need to be engineered in full– just like one does not need to assemble (or understand for that matter) a computer in order to write great software. As we understand how to apply metabolic functions of existing species to our needs, we enter into a symbiotic relationship. They become technology.

‘Dark Life’ is ripe with fruitful tech: picking it is a matter of choice and funding.

Origins of Existential Risk

The industrial revolution and its effect on crop yield are generally praised. But the timescales we look at are rather short. Improvements in yield may not ensure food supply longterm.

Modern agriculture has a large carbon footprint and chemical fertilisers are destroying the health of our soils (at the rate of a fertile area of 30 soccer fields/​minute). Despite a 700-fold increase in the use of pesticides during the second half of the 20th century, yield remains constant but 20-40% of domesticated plants are still lost to pathogens.

A deterioration of soil health is followed by a disruption of symbiotic exchanges between fungi and plants. Fungi no longer fuel the immune system of plants. Crop resilience against pathogens, temperature extremes, heavy metals and salt decreases. As much as they help, fungi don’t generate the kind of artificial yield we have become used to: we observe a trade-off between resilience and maximal yield.

From a perspective of a longtermist, this case study is an emblematic story of how we often choose to increase yield in the short-term, in exchange for long-term benefits. And whilst our climate seems stable, modern agriculture may look like a technological success story in support of Steven Pinker. But we know the climate is about to be anything but stable. We may have traded a rich-looking exploit, for anti-fragility. This was probably an unwise trade. From the perspective of longtermism, it may simply have been stupid.

Such case studies might lead us to re-examine the origins of anthropogenic risk to our longterm flourishing. Longtermists must think more thoroughly longterm. We must consider whether what looks like an arch of progress over decades, could turn out to have been a mere depletion of resilience and thus a shift of the risk-distribution. Improvements in quantity of anything must come from somewhere, and we better make sure they don’t derive from the buffers we need in tougher times.

In Conclusion

Fungi are impressive, significantly under-explored and could be the solution to many issues. Thinking about them brings joy and challenges notions of resilience, species extinction and preservation. We should consider investing into more neglected research in this area.