The Holobiont's Decisional System: A Comment by Helga Ingeborg Vierich

Helga in Botswana with two Kua friends (image source)

A post by Helga Ingeborg Vierich


Here, Helga comments on my previous post "Why do we Always Choose the Decisional System that do the Most Damage," where I discuss the case of the sinking of the "El Faro" ship, caused by the way the command structure was organized. "Pyramidal" decisional systems place the power in the hands of a single person, (typically a man) and the person in charge doesn't have the flexibility to change his opinion, nor the capability to access the data on what's really happening. A Holobiont-like decisional system is much more flexible and attuned to the real world, as Helga describes here.  



Dear Ugo; this is wonderful.

It explains the danger of hierarchies of powerful authority so clearly! I am teaching introductory sociology this term and will be making this one of the supplemental readings, for the topic right now is the development of state-level societies. It is, indeed, in state-level societies that we see the development of these kinds of hierarchies.

People have frequently pointed to the pecking order of chickens, and the evidence of hierarchies based on aggression in chimpanzees and baboons, and used this as a justification for human hierarchical social organization. As if it were, thus, "natural". But everything we know now, about the social organization and behaviour of people in "tribal" and "band" level societies (based on hunting, gathering, fishing, swidden horticulture, or nomadic pastoralism) suggests that before the state developed, seniority-based hierarchies of authority rare, and socio-economic and power-based hierarchies were unknown. Decisions were rarely made without extensive discussion.

The whole dynamic of morality in forager economies is to enforce a degree of social equality: the networks are based on relationships of mutual support, not chains of authority. There are no permanent leadership positions. Group actions to enforce punishment of transgressors appear to arrive through consultation and consensus.

We find these forms of consensus-creation preserved in tribal societies as well, even those with more permanent leadership positions. This is perfectly articulated in the following:

“...Roland Chrisjohn, a member of the Iroquois tribe and the author of The Circle Game, points out that for his people, it is deemed valuable to spend whatever time necessary to achieve consensus so as to prevent such resentment. By the standards of Western civilization, this is highly inefficient.

“Achieving consensus could take forever!” exclaimed an attendee of a talk Chrisjohn gave. Chrisjohn responded, “What else is there more important to do?”” (quoted from
http://www.filmsforaction.org/articles/the-more-a-society-coerces-its-people-the- greater-the-chance-of-mental-illness/ )

Unlike the hierarchical systems in many larger primates, like chimpanzees, ranking systems among foragers and even among pastoral and horticultural peoples, are not derived from intimidation and aggression, but by acquired reputation for demonstrated moral virtues - like articulating a consensus. Such people are valued by the community and thus listened to, only after a history of demonstrated integrity involving a list of highly valued signs of good character: generosity, diplomacy, honesty, loyalty and recognized proficiency at important skills (hunting, gathering, cooking, singing, trance-dancing, music, storytelling or comedy).

In other words, they are people of high rank and good reputation. Among hunter-gatherers, therefore, differences in social rank rarely result in social inequality of access to vital goods and services, but instead, ensure such access.

Indeed, aggressive hierarchies are not even innate, even in baboons. Such behaviour is cultural - learned and shared. This was shown very clearly in Richard Sapolsky's story of his Keekorok baboon troop, and how after the alpha males died from tuberculosis, the troop very quickly transformed into a very peaceful troop, and since then, a peaceful approach has become a cultural norm for them. This was in contrast to the normal high levels of stress in the aggressive hierarchies of baboons. Sapolski's research indicates that stress created by hierarchies is a killer in human societies, and he is not alone in saying this. Gabor Mate has been very clear on this too, and has linked stress, addictions, and even the addiction to power.

Yes, our societies, in the world today, need to become more of a holobiont: the integration of many co-dependents is always going to produce a less dangerous and stressful alternative.


regards, Helga

Chip 'n Dale: Holobionts

 

Do you remember Chip 'n Dale? They were created by Walt Disney in 1943. It seemed wholly natural to viewers that they had a nice home inside the trunk of hollow trees. The idea that they were looking for natural cavities appeared from their very first story, which had to do with their attempt to settle inside the barrel of a cannon. 

Cannons are still abundant in the world, but hollow trees don't seem to be so common anymore. Think about that: have you ever seen a hollow tree outside horror fiction or cartoons? I never saw a hollow tree comparable to the fictional ones. It is only in parks that keep old trees that, occasionally, you can still see hollow trees, but rarely with those huge hollows where Chip and Dale could make their home. 

Yet, hollow trees have a special fascination and are part of forest lore everywhere in the world. They are not just fascinating for human beings, they are also home to all sorts of animal species. Birds, typically, but also larger ones, such as raccoons and even bears. In this sense, hollow trees are a feature of the forest holobiont, just one of the many multispecies holobionts that keep the ecosystem alive and adaptable. 

The formation of a hole on a tree stem is a wholly natural process that's generated, normally, by the action of specialized saprophyte fungi -- although woodpeckers can initiate the process and, sometimes, dig quite substantial holes. The plant is not normally harmed by one or a few hollows. Old trees tend to accumulate hollows, and when they die they become "snags," not anymore live trees, but still part of the forest ecosystem, homes to a variety of animal species.  

So, why so few hollow trees around? Have they become an abomination? Apparently, yes, I have a fig tree in my garden with a few hollows in the stem, and everyone who sees it asks when we are going to cut it. And that's the destiny of hollow trees everywhere. If you look at the term on the Web, you'll find plenty of pages describing "hollow tree removal services." It seems that hollow trees are indeed seen as a monstrosity, slated to be eliminated as soon as possible. And whenever a tree develops a hollow, it is plugged with cement or silicon, or whatever. 

More in general, hollow trees are a victim of the "optimization" trend in forest management. It doesn't matter whether it is a plantation or a park, if the idea is to make trees grow as fast as possible, then hollow ones have to be removed. It is typical of human management: it is aimed at maximizing just one of the parameters of the system. Instead, holobionts aim at optimizing all the parameters together. Humans aim at yield, holobionts aim at stability. Maybe, one day, humans will learn, and maybe they are already starting to learn. In the book "Chanterelle Dreams" by Greg Marley, you can find an entire chapter dedicate to how to restore tree hollows for cavity nesters. Some creative methods can be used, such as using shotguns to shoot slugs packed with fungal spawn into the bulk of a tree stem. It seems to be working -- so, not everyone marching into a forest with a shotgun in hand is there to do damage!

Up to not long ago, I was convinced that, apart from my fig tree, hollow trees had been scientifically exterminated in all the areas close to where I live. Instead, I discovered that the avenue just near my home is lined by wonderful honeyberry trees ("bagolari" in Italian), most of which have numerous, well-visible hollows. Some are clearly the result of branches having been cut off, others may have developed by themselves. I won't tell you where exactly this place is, least someone decides to cut these trees for being "dangerous" or to plug the hollows with cement. As far as I can say, these cavities are not inhabited by birds or other animals, probably because they line a trafficked road. But it is nice to know that there are places where owls, squirrels, and maybe Chip and Dale could take refuge if they decided to live in this area. Here are a few pictures. 

How Gaia Saved the Earth from a Cold Death

 

The Goddess Gaia in the form of the winter deity Khione, daughter of Boreas, the North Wind, and the Athenian princess Oreithyia (image by "Nobody-Important"). 

Earth is a fragile planet and it might freeze to a snowball if not taken care of. So far, the Goddess has done a good job at that but, at least a couple of times during the past few billion years, the Earth actually froze. Might that happen again? It seems that we were close to that just a few tens of thousands of years ago. Now, the problem doesn't exist anymore, with humans pumping zillions of tons of greenhouse gases into the atmosphere. And, who knows? Humans could be the tool used by the Goddess to avoid another "snowball Earth." But now we may have too much of a good thing and the Earth risks boiling. Hopefully, Gaia can take care of that, too.   

It is always amazing to realize how complex is the system that we call the "Ecosphere". And how the system's complexity keeps its parameters within the limits needed for life to exist and prosper. It is the concept of "Gaia" as it was proposed by James Lovelock and Lynn Margulis. The ecosystem is in homeostasis and tends to maintain relatively constant parameters by means of a tangle of internal feedbacks, as all complex adaptive systems ("CAS") do. 

But homeostasis doesn't mean perfect stability. The system's parameters may oscillate - even wildly - before the internal feedbacks can bring them back to the "good" values. Sometimes the system gets close to its limits and it may well be that, at times in its long history, the ecosystem risked going over the edge and then Gaia could "die." This seems to be a common destiny for extrasolar planets, as recently argued by Chopra and Linewaver.

A recent paper by Galbraith and Eggleston on Nature starts from these concepts, noting how the concentration of CO2 in the atmosphere never went below ca. 190 ppm during the past 800,000 years. That happened in correspondence with the lowest temperatures ever observed during that period: the planet was going through a harsh ice age.

This figure from a recent paper by Galbraith and Eggleston on Nature shows an interesting fact: the concentration of CO2 in the atmosphere never went below ca. 190 ppm over the past million years or so. Possibly, it touched the danger limit for the ecosystem to survive. For lower concentrations, plants wouldn't have been able to perform photosynthesis and the biosphere would have largely disappeared.

About these ice ages, there is an interesting point related to the system's feedback. The more ice there is, the more reflective the planet's surface becomes (more exactly, the planetary albedo increases). But, the more reflective the planet's surface is, the cooler the planet becomes. So, we have an enhancing feedback that may transform the whole planet into a single, frozen ball: "snowball earth". It has happened, although possibly not completely, at least twice in the history of Earth. It was during the period we call, appropriately "Cryogenian," from 720 to 635 million years ago. It was not a real "snowball" -- not all of Earth was covered in ice. But what was not under the ice was a frozen desert. To give you some idea of the fascination of this subject, here is an excerpt from the abstract of a paper by Hoffmann et al. on "Science"

"....the small thermal inertia of a globally frozensurface reverses the annual mean tropical atmospheric circulation, producing an equatorial desert and net snow and frost accumulation elsewhere. Oceanic ice thickens, forming a sea glacier that flows gravitationally toward the equator, sustained by the hydrologic cycle and by basal freezing and melting. Tropical ice sheets flow faster as CO2rises but lose mass and become sensitive to orbital changes. Equatorial dust accumulation engenders supraglacial oligotrophic meltwater ecosystems, favorable for cyanobacteria and certain eukaryotes. Meltwater flushing through cracks enables organic burial and submarine deposition of airborne volcanic ash. The sub-glacial ocean is turbulent and well mixed, in response to geothermal heating and heat loss through the icecover, increasing with latitude. Terminal carbonate deposits, unique to Cryogenian glaciations, are products of intense weathering and ocean stratification. "

Can you imagine the Earth in these conditions? A wasteland of dry deserts and ice sheets. At that time, there were no multicellular creatures and life may have survived in hot pockets, maybe volcanic lakes, where it was still possible to find liquid water. 

We may have been dangerously close to a new snowball Earth episode during the past million years or so. Not a trifling matter because today the ecosphere is much more complex than it was at the time of the Cryogenian. A new snowball Earth would likely cause all vertebrate lifeforms to go extinct. It is not just a question of being too cold: the limit of concentration of CO2 that permits plants to perform photosynthesis at a reasonable rate is considered to be around 150 ppm, at least for the most common kind of plants. Under that value, all multicellular plants die, and with them all animal life. Only single-celled creatures could eke out a precarious existence in those conditions. 

But something prevented the ice sheets to expand all the way to envelop the whole Earth and, at the same time, prevented the CO2 concentration to go below 190 ppm. What was that? Several hypotheses are possible. Galbraith and Eggleston favor a biological one, saying that:

In terrestrial ecosystems, carbon fixation by plants is limited by low ambient CO2 (ref. 31). On this basis, ref. 12 proposed that CO2-limitation had significantly reduced plant-mediated silicate weathering during low-CO2 intervals of the past 24 million years, thereby enforcing a lower bound on the ocean–atmosphere carbon inventory over >10^5 yr timescales. Subsequent experiments have been consistent with this ‘carbon starvation’ mechanism, showing reduced weathering by tree-root-associated fungi under low CO2 (ref. 32). Although the feedback on silicate weathering would appear too slow to play a role on the 104 yr timescale of glacial CO2 minima 30, it may be possible that strongly reduced weathering rates lowered ocean alkalinity (thereby decreasing CO2 solubility) on a millennial timescale. Alternatively, reduced photosynthesis rates during the LGM (last glacial maximum) would have slowed the accumulation of terrestrial biomass14, consistent with estimates for lower terrestrial primary production rates33. By slowing the accumulation of carbon in vegetation and soils, this would have provided a stabilizing feedback via an increase of the ocean–atmosphere carbon pool.

Complicated stuff, right? But, basically, the idea is that CO2 is slowly drawn down from the atmosphere by a reaction with rocks (silicates), forming carbonates. This reaction is called "weathering" and it is favored by plants, whose roots provide a good environment for it to take place. Fewer plants, less CO2 drawdown. At the same time, a smaller global biomass means that the quantity of CO2 stored in it becomes lower and this extra carbon most likely ends up in the atmosphere as CO2. So, there are two feedbacks embedded in the system that tend to stabilize its temperature. But, as you may understand from the text by Galbraith and Eggleston, it is even more complicated than this! In any case, these stabilizing geobiological feedbacks oppose the ice/albedo feedback and tend to slow down the glaciation before the two sides of the ice sheet touch each other at the equator. 

But suppose that the Earth really became the snowball that some studies claim to have observed: how did it recover? If it is frozen, it is frozen. Maybe not completely dead, but poor Gaia was reduced to a minor sprite inhabiting hot springs. How could Earth return to the lush ecosphere we are used to?

There is an explanation: it is because volcanoes do not care whether the Earth's surface is frozen or not. They continue pumping CO2 and other greenhouse gases into the atmosphere. Again from Hofmann et al. 

“If a global glaciation were to occur, the rate of silicate weathering should fall very nearly to zero (due to the cessation of nor-mal processes of precipitation, erosion, and runoff), and carbon dioxideshould accumulate in the atmosphere at whatever rate it is releasedfrom volcanoes. Even the present rate of release would yield 1 bar ofcarbon dioxide in only 20 million years. The resultant large green houseeffect should melt the ice cover in a geologically short period of time”[(69), p. 9781]. Because Snowball Earth surface temperatures are below the freezing point of water everywhere, due to high planetary albedo,there is no rain to scrub CO2(insoluble in snow) from the atmosphere."

Note one subtle detail: if temperatures were to go below the freezing point of CO2 (-78 C) even in small regions at the poles, that would form a nearly infinite CO2 sink. And that would be "snowball forever" -- maybe it would have made the Goddess Khione happy, but it didn't happen. Possibly, that was too cold even for a Winter Goddess!

In any case, it seems that CO2 was pumped into the atmosphere by volcanoes, maybe it was the work of the volcanic form of Gaia, the goddess Pele, known for her habit of taking lava showers. 

When the CO2 concentration arrived at levels hundreds of times those of the present-day atmosphere, the result was a cataclysmic rapid collapse of the glaciers and a rise in temperatures. Not only the Earth's ecosystem was saved from a cold death, but it rebounded spectacularly: it was now the time of the "metazoa," the formal term indicate animals. There came the Cenozoic, in which we are still living, with its incredible variety of lifeforms when plants and animals colonized the continental lands. 

You see how the job of Gaia is not so simple. it involves a delicate balance of many factors. Some tend to stabilize the system, while others tend to destabilize it. During the past 15 million years or so, cooling factors took the lead and slowly pushed Earth to lower and lower CO2 concentrations and, with that, lower temperatures.

 Image from Wikipedia Commons. The x scale is in million years from the present. Note the rapid cooling of the past million years or so.

We do not know exactly what caused the cooling, there are several theories. But one thing is sure, Gaia started feeling that it was too cold for her, even in her form of Khiome, goddess of ice. She could die and, this time, perhaps for good. 

(Image source)

So, it became imperative for Gaia to mobilize some of the geosphere carbon and push it into the atmosphere in the form of a greenhouse gas that would warm the Earth back to comfortable temperatures. The Goddess Pele was too slow for that, maybe she is now a little tired after blowing CO2 into the atmosphere for four billion years. So, maybe Gaia thought of a more creative solution. 

Why not use those clever monkeys which had just evolved in Earth's savannas to dig carbon out of Earth's crust, combine it with oxygen, and then pump it back into the atmosphere?  It worked: in just a few hundred years, the monkeys managed to bring back the CO2 concentration to the levels that were typical of Earth as it was a few tens of millions of years ago. 

It may be that, now, Gaia faces the opposite problem: those monkeys have pumped so much CO2 into the atmosphere that now we risk pushing the planet on the opposite side of a climate collapse, to a "hothouse Earth" that might kill the biosphere. Something like that happened with the great extinctions at the end of the Permian and the Cretaceous. Alas, life is difficult, but Gaia can cope. Does that mean getting rid of those pesky carbon-burning monkeys? Maybe. After all, Gaia is a Goddess, she ought to know what she is doing and she has no qualms when it is time to do what's to be done. She can find ways. 

(Image Source)

Holobionts of all the world, unite against totalitarianism!

 

Image from the Genetic Literacy Project

This is taken from a discussion we had with the members of the mailing list "The Proud Holobionts" a couple of weeks ago. It is inspired by the chapter that I am preparing for the book "Life and the Construction of Reality" edited by Pierre Imbrogiano and David Skrbina. 

I keep finding hugely interesting things on the Web. Too many, and I am losing a lot of time following links that lead me to unexpected discoveries. But so is life and, just to make you suffer as much as I do, let me alert you about this paper by Harald Walach, researcher in the field of medicine and psychology. The post is a comment about Mattias Desmet's "The Psychology of Totalitarianism" -- another hugely interesting thing that I am trying to avoid reading because it would completely absorb me for days.

So, here is the link to Walach's paper

https://harald-walach.info/2022/10/17/a-middle-way-in-difficult-times/

The point that Walach makes does not look like it is related to Holobionts, but, in my opinion, it is. Read this, first, from the paper:

"The ideology of naturalism has become more and more widespread since the beginning of the Enlightenment and dominates the brains and hearts of many people, especially those in important positions in science, politics, business, the media, and perhaps even religions. It leads to people feeling more and more like isolated atoms in a world without meaning or purpose. This gives rise to fear. But this fear has no goal, it just lies there. In psychology, we speak of “free-floating fear”. It leads to frustration and aggression. If this is the case with a large number of people, then this fear will always look for a new object to direct itself towards Terrorists, Islamists, foreigners, climate catastrophe – or a pandemic.

"In such a situation, self-organization processes emerge that lead relatively quickly to new structures, new patterns, and new orders – the “new normal” – which then suddenly seem very logical. These self-organization processes seem to be so well coordinated that one cannot imagine them arising of their own accord. But they do in fact arise of their own accord. Towards the end of his book, Mattias Desmet presents a few striking examples from chaos theory that explain how such things work.

"And now something important happens: the formerly atomised individuals, each bobbing along in a meaningless and empty world, now suddenly feel a new sense of purpose. And above all: they feel new connectedness with others. All are united in fighting this new threat and something emerges that they have not felt for a long time: a sense of belonging, of connection, of solidarity with others.

This in turn leads to the in-group of believers, similar to the members of religious groups or political parties, feeling good internally and delimiting themselves externally: against the others, the pagans, the unbelievers, the sceptics and doubters. Their arguments, threats against the newly created world view, are thus devalued, no longer find a hearing, no longer penetrate the channels of reporting of the mainstream media, but have to look for side channels."

Walach (and Desmet) have a perfectly fundamental point. Atomized individuals seek "something" -- an idea, a religion, a leader, a master, something that gives meaning to their life. The result is often "totalitarianism" in the sense that the atomized individuals find themselves at home under an "umbrella" organization that rules them from above. If you have friends in the military, you may notice how many of them feel about that. They recognize the enormous defects and inefficiency of military organizations but, all the same, they feel comfortable with the idea of belonging to a tight group that gives them a purpose.

Walach proposes a solution. He says, "The solution is to speak. Words trigger hypnosis. Words can also release it. By speaking, writing, discussing, whether in public, at home or at work." It can't work with the true believers, but Walach doesn't suggest speaking to the hypnotized, but to that fraction of the population that's not completely dazed by the propaganda barrage they receive. But it is not easy, and you always risk pushing the lukewarm ones into the group of those burning with faith.

It may work, but I am not sure about that. Walach and Desmet may have identified the problem, but that doesn't mean that the solution is good. The way I see this matter is that totalitarian structures are "vertical." That is, a true totalitarian organization is one in which you only communicate with those above you, and those below you, but not with those at the same level. Because of this structure, whatever comes from the top diffuses down, and is not subjected to discussion. You know that it is bad: it means that the mistakes made at the top cannot be corrected -- there is just no mechanism for the bottom layers to influence the top layers. If there is, it is very weak and easily perverted, just like our election. But it is a structure that makes you feel safe, so you accept it. 

So, if we want to change the vertical structure we must propose a different form of organization that can provide some of the same benefits, without being so rigid and inflexible as the typical hierarchical pyramid. So, what if we were to propose the holobiont as the social structure that avoids totalitarianism? If you are part of a holobiont, you don't have a master. Holobionts are non-hierarchical networks mainly based on local interactions among nodes (e.g. people). Typically they are smaller than hierarchic networks and tend to form higher order holobionts forming fractal structure. Mutual holobiontic interactions are based on self-respect and they have harmony as their purpose. It is a horizontal kind of network. 

A holobiont may be slower to react than a hierarchical structure because the signal that comes from an outside perturbation needs to diffuse from node to node, and that takes time. But it is more flexible and I believe it can avoid the terrible mistakes that pyramidal structures are known to do. 

Could that be the way to avoid totalitarianism? I am not sure, but I think it is at least a promising idea. And, in any case, the push toward localism and relocalization is evident everywhere. We still have to learn how to make large hierarchical organizations, and maybe the best idea is just to avoid building them! 

Onward, fellow holobionts!

The Meeting of Civilizations that wasn't

 

This is the absolute top interpretation of the "Rondeau des Indes Galantes" by Jean-Philippe Rameau. This version is by Clement Cogitore, Opera de Paris (h/t Luisella Chiavenuto).  

In 1723, Jean-Philippe Rameau wrote the music for an Opera titled "Les Indes Galantes" (The Romantic Indies) that took as inspiration the non-European world. A section of the Opera takes place in the world of Native Americans. It tells a romantic and improbable story, that of the native princess Zima, who is contended by three young men, a native named Adario, the Spaniard Don Alvar, and the Frenchman Damon. Eventually, she decides for Adario and the couple takes refuge in the "pleasant forest" where "Greatness never comes with its false enticements" 

Naive as you like, it is still a precious relic from an age in which Europeans had been encountering the Native Americans on a more or less even foot. An age in which Europeans thought that they could learn something from the American culture. An age in which it was legitimate for a European to marry a native. The French may have been especially affected by Native cultures and it is said that the ideals of the French revolution, freedom, equality, fraternity, were inspired by Native American cultures.

Not long afterward, it was all gone. A little more than a century after Rameau's opera, there came the ethnic cleansing of the Native Americans under the "Indian Removal" laws. It was the "Trail of Tears" that removed the American Indians of the "Five Civilized Tribes" from their homelands and pushed them to the Western side of the Mississippi, to survive the best they could, if they could. Over the following century, the natives were gradually exterminated, their culture was destroyed, their forests razed to the ground. 

You may be interested in some data about this extermination, taken from the manuscript of a book that I am planning to publish one day or another. 

___________________________________________________________________

Paradoxically, just because the conquest of Mexico was so fast and so brutal, the Europeans found it useful to maintain at least some local social and economic structures. It doesn’t mean that the Native population was not exterminated by a combination of starvation, slavery, overexploitation, and violence. But that took time and, in the process, there was a chance for the two populations to intermingle and share genes and cultural memes. In genetic terms, the modern population of Mexico is highly mixed. The “Mestizos,” people of mixed Native and European ancestry, form some 60%-90% of the total population (the exact number depends on the criteria used to define them). It is reported that, on the average, their genes are nearly 80% native, the rest being “Iberian” (that is, Spanish). From a cultural viewpoint, the Mesoamerican heritage is still alive and several Native languages, such as the Guaraní in Paraguay or the Nahuatl in Mexico, are still spoken by a sufficient number of speakers that their survival is not at risk. It is said that the Mexican revolutionary leader, Emiliano Zapata (1879- 1919), was of Indio origin and that he could speak Nahuatl.

A similar story holds for South America. The Europeans defeated the Inca Empire, but maintained some of its structures, and the two populations had the time to intermingle. The retreat of the Natives involved fights and several extermination episodes, but sometimes the Natives offered a successful resistance. In 1598, at the battle of Curalaba in Southern Chile (that the Spanish call the “Disaster of Curalaba”) the Mapuches, one of the Andean populations, managed to defeat the Spanish and force them to abandon seven of their cities (Destrucción de las siete ciudades). The last phase of the fight in South America was a defeat for the Natives, with the “Conquest of the Desert” in the 1870s, carried out by the Argentine army over the Patagonian Desert. Which was not exactly a desert, since it was inhabited by the Mapuche. It was a full-fledged ethnical cleansing campaign that led to the extermination and removal of the Indios, leaving space for the European settlers to move there. Yet, as an indication of the fierce resistance of the Mapuche, at least one world of their language became part of the Argentinian vocabulary. It was “Malón,” from “maleu,” meaning “to inflict damage to the enemy.” In its modern usage, the term indicates a plunder raid of the Indios.

Although modern Argentinians see themselves as of European descent, they mostly are of mixed blood. Genetic studies have shown that the average ancestry of the Argentinians is no more than 65% Iberian, but the rest is from Native populations, plus a small percentage (around 4%) of Africans. A similar result holds for Chile, with an even larger (almost 50%) percentage of Native ancestry. The Brazilians are a little more European than both Argentinians and Chileans, but only marginally so, with an average of about 70% of European genes. It is probably the result of a recent immigration trend from Europe. Other South-American countries have similar admixtures.

That doesn’t mean that the mixing of the European and the Native genes always took place in a friendly manner. It is perfectly possible that male European settlers enslaved or raped Native women, but also the reverse is possible, as described, for instance, in the short story by Jorge Luis Borges, "Historia del Guerrero y la cautiva" (1949). The genetic analysis cannot tell us much about that, although some data indicate that the mixing occurred mostly between European males and Native females. In any case, it happened.

The case of North America is completely different. The average fraction of Native American genes in the DNA of US citizens of European descent is nearly zero, less than 0.2%. Mixed marriages just didn’t take place, except in the early times, when Pocahontas (1596-1617) married a British colonist. In later times, intermarriage was not just uncommon in North America, it was prohibited by law. “Anti-miscegenation laws” that made intermarriage a felony existed in the US until the 1960s.

For a period, the Native confederacies successfully opposed the European invasion. During the 17th and 18th centuries, the technological differences between the Indians and the Europeans were not large. The Natives soon learned how to use muskets and deployed them against the Europeans, sometimes with great success. A nearly forgotten case is that of the “Battle of the Wabash”, or the “Battle of Wabash River” in present-day Ohio. It was fought in 1791 by the US army against a coalition of Native American tribes. The Indians used a combination of muskets and bows to inflict about a thousand casualties on a force of some 1500 men of the US army. In terms of relative casualties, it was probably the worst defeat ever suffered by the US army. The 18th century may have been the last opportunity for the Natives to become independent states on an equal footing with the US. But, with the 19th century, things changed for the worse for them. 

Despite the victory at the Wabash River, the subsequent battles were all defeats for the Indians. Eventually, the balance of power tilted decisively in favor of the Whites. It was during this period that several US states also enacted anti-miscegenation laws, forbidding mixed marriages between Whites and Natives. In 1830, the US congress enacted the “Indian Removal Act,” the forced removal of all the natives residing East of the Mississippi River, to settle on the other side. During the fall and winter of 1838 and 1839, the Cherokees and other tribes were forced to march Westward. It became known as the "Trail of Tears." We don’t know how many died on the trail, at least several thousand. Then, we don’t know how the Natives fared on the new lands, having arrived there with nothing more than the clothes they were wearing. That was the end of all attempts at statehood for the Indians of North America.

After having pushed Natives West of the Mississippi, the Europeans had not much more to do than mopping up the remaining resistance. By the mid-19th century, the superiority of the Whites’ armies had become overwhelming. They had cannons and sometimes even used Gatling machine guns. But there was little need for very sophisticated weaponry: at the Battle of Four Lakes, near modern-day Spokane, Washington, in 1858, the Natives were annihilated by the US army using only simple, single-shot Springfield rifles. The last hurrah for the Indians was the battle of Little Big Horn, in 1876, when a group of Lakota Indians defeated and exterminated a detachment of the US Army led by General Custer. But the mopping continued, and it even accelerated. The massacre of the Lakota Indians at Wounded Knee (1890) was the last action of some relevance of the Indian wars. By the end of the 19th century, all the Natives of North America had been either killed or forced into reservations.

There remains to explain how the extermination of the North American natives left no chance for the exterminated to intermarry with the exterminators. That was an exceptional event in history. From the times of the Trojan war, it was traditional that the males of the defeated population were killed or enslaved, but that the women were spared and taken as slaves or concubines. For instance, Cassandra, King Priam’s “most beautiful daughter,” was taken as a concubine by Agamemnon, the leader of the Achaeans. Bad as it was, this ancient way to deal with the defeated left them at least a chance for a form of survival. Their genes would leave a trace with the winners’ descendants.

Homer’s description of the Trojan war is, of course, fictional, but history agrees with his tale. Think of the replacement of the Neanderthals by the Sapiens in Europe. If you are European, today, you probably carry about 2% of Neanderthal genes in your DNA. It means that some of your remote ancestors were Neanderthals! But that’s more than modern US citizens of European descent carry in terms of Native genes. To understand how violent, even ferocious, the relations between Whites and Indians in North America were, we can look at the story reported by Jeremiah Curtin (1835 – 1906) in his “Creation Myths of Primitive America” (1898). In the book we read of an event that took place in 1864 in California (as reported in “Ishi, the Last Yahi” 1981 (55)) :

A few miles north of Millville lived a Yana girl named Eliza, industrious and much liked by those who knew her. She was working for a farmer at the time. The party stopped before this house and three of the men entered it. “Eliza, come out”, said one of them, “we are going to kill you.” She begged for her life. To the spokesman, who had worked for her employer some time before, she said; “Don’t kill me; when you were here I cooked for you, I washed for you, I was kind to you; I never asked pay of you; don’t kill me now.” Her prayers were vain, they took Eliza, with her aunt and her uncle, a short distance from the house and shot the three. My informant counted eleven bullets in Eliza’s breast. After this murder, the party took a drink and started, but the leader in killing Eliza said “I don’t think that the little squaw is dead yet.” He turned back, smashed in her skull with his musket.

Not that there were no cases of wanton killings in ancient history, but this is truly extreme. Note that the killers were most likely drunk (they “took a drink,” probably it was not the first one). But did Agamemnon spare Cassandra just because, at the time of the Trojan war, whiskey had not been invented? The ferocity of the behavior of European Americans against the Natives has no parallel in history.

What is left, today, is little more than fragments of a disappeared world and the beautiful music of Rameau's "Les Indes Galantes" that tells us something of a meeting of civilizations that could have been, but never was.  

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Other versions of the Rondeau des Indes Galantes: 

This splendid version is by Les Arts Florissants with Magali Léger and Laurent Naouri. 

Another fabulous interpretation by Les Arts Flourissants

The one below will literally blow you away, although it was made by one of those bloodthirsty Russian barbarians. 

And just another powerful and heartfelt version with Sandrine Piau, Lisandro Abadie, again by les Arts Florissants

This is a sort of comic-book version. But consider it carefully: it is very pleasant and extremely well done. An early version by Les Arts Florissants

Here are the words, in French. Zima is the native princess and Adario is her lover. 

Zima, Adario en duo Forêt paisibles, Jamais un vain désir ne trouble ici nos coeurs. S'ils sont sensibles, Fortune, ce n'est pas au prix de tes faveurs. Choeur des sauvages Forêt paisibles, Jamais un vain désir ne trouble ici nos coeurs. S'ils sont sensibles, Fortune, ce n'est pas au prix de tes faveurs. Zima, Adario Dans nos retraites, Grandeur, ne viens jamais offrir de tes faux attraits ! Ciel, tu les as faites pour l'innoncence et pour la paix. Jouissons dans nos asiles, Jouissons des biens tranquilles ! Ah ! Peut-on être heureux, Quand on forme d'autres voeux ?

Learning from plants: how to become a forest

 

The Boboli Garden in Florence, which Andrea Battiata cites as an example of harmony and connectedness. Battiata is an agronomist living in Florence who set up a vegetable garden called "ortobioattivo" where he cultivates vegetables using only natural methods. Here, he does not directly mention holobionts but makes a fundamental point on how the network of a forest is organized as a holobiont, and how we, humans, could learn a lot from forests. Even to the point of "becoming" a forest. It is a deep, deep point. You can compare Battiata's considerations with those of Blair Fix, a Canadian physicist. We have a big problem with an entity we created, perhaps unwillingly, the human social hierarchy, which may be the ultimate origin of the economic inequality in the world. The ways of holobionts are many, but all are worth following.  

by Andrea Battiata 

Over the past decade, in which I have begun to produce food that is good for people and at the same time does not deplete the fertility of the earth, I have felt fortunate to have co-created meaningful relationships that are deeply connected.  I realize now that the intense training to become a co-evolutionary agronomist was, more than anything else, a prelude to receiving lessons from plants and from how plants are virtuous.

Beautiful are the gatherings at my garden, "Ortobioattivo" where people get together with others who understand their concern for the future and share the enormous range of emotional intensity surrounding their lifestyle. These things matter, because loneliness is a disease in and of itself. There is much research to support this: one scientific study showed that people who had weaker social ties were 50 percent more likely to die early than those with stronger ties. Being disconnected, in fact, poses a danger comparable to smoking fifteen cigarettes a day and was more predictive of early death than the effects of air pollution or physical inactivity.

It is the sense of belonging to something greater than one's existential loneliness and the tangible support derived from this sense that makes us feel vital; connection is so important to us, humans, that without it we wither and may even die. In our first months of life, we are cradled, kissed, and hugged, and, along with eye contact, we receive loving touch and hear our names spoken to us.

We are programmed for this. We are evolving to relate to each other. The search for models and ideas for building communities that relate to and improve their existence with food has become a way of life for me. 

I think that if we can create places and spaces that give what we are looking for such as connection with nature, interaction or physical proximity to each other, a structure that provides opportunities for community building, services, and learning appropriate lifestyles to make us feel good by feeding well, we can be a "forest", helping each other just like plants that stay together and help each other.

The nature of plants shows us the way how communities grow and thrive despite, overcoming the challenges of finding space, light, and fertile soil. 

Nature does this. Every day, from an evolutionary perspective. 

I think we can do it too.

Plant communities are constantly adapting to their environments: growing deep tap roots when water is scarce, flowering at night to prevent dehydration and growing bright and colorful flowers to attract pollinators. Together they create ingenious ways to survive and thrive even in harsh deserts and tropical forests. Humans, too, can find a connection with the Earth. We long for membership in a community and constantly work to adapt to the negative factors of isolation and separation that we face and often create. As scientific research and experience show, as our social ties weaken and our sense of belonging diminishes, we lose one of the great possibilities for resilience to the negative factors of daily life.  

The COVID-19 pandemic has revealed to us, through the difficulties of our continued isolation and estrangement, that we are a species with a deep need for connection. Exactly like the mycelium of fungi that communicates in an uinderground network, good human community functions as a huge underground support system, allowing us to live well above ground in our individual bodies. We are attached to the Earth, physically and metaphorically. Looking to Nature for healthy living patterns makes sense, and it is there that wisdom can be found in times of trouble.

Many of the most successful health models are literally outside our windows and based in communities. Here in Florence, in early fall, I look out the window at the Boboli Gardens, a large city park in the center of the city. The trees are in various states of change; many are already bare and some are clinging to a few multicolored leaves. They are alive, but the pulse of energy is not visible as they head into winter. Trees, of course, do not die in winter but become dormant. It is a semi-hibernation that cause everything inside the tree to slow down: metabolism, energy consumption, growth. Since they do not produce photosynthesis and thus energy in winter, they release their leaves, which require a great deal of energy to maintain. In these autumn days, trees transfer water into their cells and, when the temperature drops, move that water from inside the cell to the tiny spaces outside, between the cells. This prevents tree cells from freezing.

Even in this dormant state, trees communicate through their root structure, sending nourishment to smaller trees around them that need it, and protecting each other by sending chemical communication messages. They work in a community. Nature is literally showing us the way to health. Communicate and be close to those you care about. Some of the answers are right there, outside the window, in our parks rich of hedges and trees, everywhere in Florence. All we have to do is look away from our computers, television screens, and cell phones to stop, listen and absorb it all.

Without dormancy, energy conservation, leaf fall, rest, restoration, a different appearance throughout the seasons, and the added benefit of a community of trees nearby, a tree may not survive for long and will not have the much-needed energy to thrive and gather sun from the sky and nutrients from the earth. With these adaptations, a tree can survive several challenging seasons.

The simplicity of this lesson is lost in the complexity of human life. There are people who are burning their energy on all fronts: work, family, conflict, poverty, violence, wars, and stress from multiple sources.

And while the narrative may be different for each person, the message of becoming like a tree may be the same. This unhealthy living condition is creating a winter, and inner health and strength must be preserved by limiting emotional expenditure in every way possible. Having a community to lean on when winter is upon us can make a significant difference in healing, mental health and spiritual stability. In the end, like trees and mushrooms.

Ultimately, the way of being in connection with other people and being of use, or at least listening and empathizing, is life-giving and makes us feel that we are in connection with Nature. We don't have to do anything so naturally different or unique or special to create communities to which we can all belong. Exactly like plants!

Good Holobionts don't Wear Face Masks on Planes.

 

I always wondered about the quality of the air people breathe inside the cabin of a plane. Now I know. This month, for the first time I took a CO2 concentration detector with me on a plane trip. The cabin is a crowded space, so I expected rather high levels of CO2, and I wasn't surprised that, during boarding, it rose over 3,000 ppm (parts per million), 6 times higher than in the open. But the cabin is well-ventilated during the flight, and the CO2 concentration soon settled to the value you see in the image above, ca. 1300 ppm ( but note the effect of the reduced air pressure in the cabin, see note*). Still higher than in the open, but not so bad. You can compare this value with the chart below, which lists the dangers of exposure to high CO2 levels. 

A level of 1310 ppm of CO2 is not dangerous, but it is above the limits considered healthy in normal life. As you can see in the chart below, in the cabin of a plane we are in a region where "cognitive impairment" is already measurable for several hours of exposure. That may be the reason why some people (myself included) suffer from headaches during plane trips. But, for a 2-hour flight, nothing really bad can happen to you. at most you'll feel a little dizzy.

The problem is that face masks were mandatory on this flight (a Vueling flight from Florence to Madrid). So, most people wore FFP2 masks tight on their faces. But face masks are known to raise the concentration of the air you breathe by a factor that may be 5 or even more. (see this reference). 

 

This means that the mask-wearing passengers of the plane were breathing a CO2 concentration probably in the range of 5,000-10,000 ppm, Again, take a look at the chart, above, and you'll see that nothing horrible is expected to happen to you in a few hours. But it is not a healthy condition. Especially people who are not in perfect health surely don't benefit from several hours of exposure to these conditions.  

As always, in our world, we seem to be unable to see but one problem at a time, and that problem trumps all others. If the problem is Covid, then all the other problems are ignored, including conditions that are known to create health risks. But we have no studies examining the long-term effects of wearing face masks on people who are not trained submariners or astronauts. 

I survived my trip from Florence to Madrid without a trace of a headache. But I wore a simple surgical mask and the rules allow you to take it off while you are drinking or eating (strange rules, right?). You can be sure that the coffee I had on the plane lasted for a long, long time.  

For a more in-depth discussion of the health hazards of face masks, see this recent article by Harald Walach. 

(*) The detector measures the CO2 concentration using an IR spectrometer, so it measures the absolute concentration, not the ratio of CO2 to oxygen. In the cabin of a passenger plane, the air pressure is about 75% of the value at ground level. So, if you were to increase the pressure of the same mix to 100%, your reading would go up to about 1700 ppm instead of 1300 ppm. We are still below the 2000 ppm safety limit, but much closer to it. Note also that passengers compensate for the reduction in oxygen pressure by breathing faster, and that may affect how masks influence the composition of the breathed air. It is an effect observed on children -- who breathe faster than adults, and experience a higher concentration of CO2 when wearing masks. But there are no studies available on the effects of masking in reduced pressure environments. 

Humans and Trees: They like each other, they hate each other

 

The Wochecha Mariam church in Addis Ababa. In a generally dry landscape, wherever you see a green circular area in Ethiopia, it is often around a Church. The Ethiopians have recognized long ago the value of trees as part of the spiritual experience of being human.

Humans and trees have had a difficult relationship over the past few tens of thousands of years, when humans started using stone tools and they discovered that, with some patience, a stone axe could take down a large tree. The age of deforestation is still ongoing, actually accelerating. It was not so long ago, in this extended time perspective, that the English landlord Jonah Barrington who lived in Ireland during the early 19th century, uttered a sentence that summarizes the ruthless kind human attitude toward trees: "Trees are stumps provided by nature for the repayment of debt." Somehow, we have created a frame of thought that sees no value in a tree until it is felled and sold on the market.

And yet, humans have a more complicated relationship with trees than simply cutting them down with chainsaws. It is a minority view, often disparaged with the term "tree-hugging," but it is there. Trees are something that we cannot ignore. They have been with us from the remote origins of humankind. And, sometimes, we truly feel that we need to hug a tree. Sometimes, we do, and I think it can't be so bad for one's health. In the picture, you see Grazia (Ugo Bardi's wife), hugging a Cupressus sempervirens in Italy.

Do trees perceive the presence of humans? A good question. They have a complex and sophisticated sensory system that perceives light, chemicals, and vibrations. It may well be possible that a tree can sense a human walking nearby as a combination of sounds and smells. Does a tree like to be hugged? Some questions are beyond our understanding, but they are still worth asking. And, who knows? Can we exclude that the trees of the sacred forest around a church in Ethiopia pray to God just like humans do? 

A limit to growth in food production – thoughts about the soil holobiont

What if we are not able to further increase our food production? What will we eat tomorrow?

By Thorsten Daubenfeld

As we are celebrating the 50^th anniversary of the “Limits to Growth” study I recently came across the question “how do we feed the world in upcoming years?”. Some people may argue that we already have sufficient food supply but only need a more effective and efficient system of distribution of the existing food. However, already the late Roman empire stumbled across this challenge and wasn’t able to solve it. Others argue that we have sufficient knowledge at our hands to further increase the yield of our crops (fertilizers, agrochemicals, genetically modified crops) and “technology will solve the problem”.

As a physical chemist, I love data. And the FAO (Food and Agricultural Organization of the United Nations) provides plenty of data on this topic. Together with some of my students, we decided to investigate this topic a little bit more in detail. Our key hypothesis is: There is a clear limit to growth in food production – and it already becomes visible.

We first had a look at the top 40 crops (by global production quantity) and plotted the yield (in t/ha) for each country and each of the last 60 years. Most of them showed a pattern like the one we observed for wheat (Fig. 1):

Fig. 1: Evolution of wheat yield in t/ha, 1961 – 2020. Gray dots represent wheat yield per country for the respective year, the orange line represents the global average yield (weighted by production area).

Globally, we have increased the average yield per hectare more than threefold in the last six decades. So by taking a look at the orange line in Fig. 1, we may argue that there is no indication that the growth in food production may slow down. But what could be more interesting is that there seems to be an absolute maximum in how many tonnes of wheat you are able to produce per hectare. This number has been hovering around 10 t/ha for more than 20 years. No single country, whatever they did to maximize their yield, by whatever technology that was at their hands, was able to cross this limit.

The same pattern can be observed for tomatoes, it is even more impressive in our view (Fig. 2).

 

Fig. 2: Evolution of tomato yield in t/ha, 1961 – 2020. Gray dots represent tomato yield per country for the respective year, the orange line represents the global average yield (weighted by production area).

The Netherlands was able to massively increase the yield of tomato production by growing tomatoes in greenhouses. But again, whatever they (and others) were able to do by means of technology: the biophysical limit for tomato production seems to be around 500 tonnes per hectare. No single county was able to sustainably surpass this limit in the last 30 years. Despite our celebrated technological advances in genetics and agrochemicals.

In all of the top 40 crops we examined, there is not a single example that shows any signs of (exponential) growth – rather a sigmoidal curve as for wheat and tomatoes that seems to approach a maximum value. Or no growth at all in yield.

You now may argue that we just have to learn from the “top yield countries” and copy their recipe for success to other countries. However, this has not been done, neither for wheat nor for tomatoes – nor for any of the other top 40 crops. Otherwise, we would have seen a much larger growth in recent years. But why?

Looking at the data again, we plotted the yield per country against the production area of the respective county – and obtained the picture shown in Fig. 3.

  

Fig. 3: Wheat yield per county plotted against production area. Each dot represents the yield in t/ha for one county and one year (1961-2020).

In Fig. 3, you see all countries and all yields for wheat for the years 1961-2020. Of course, this means that the same country is shown multiple times. But you see a pattern that emerges: the larger your production area, the lower your yield. And the “top yield countries” are the ones with the lowest production area. This pattern is similar for other crops as well and so far, my key takeaway would be: we cannot simply “copy” the recipe of the top-yield countries to the top-area countries. To put it simply: greenhouses for tomatoes might work for a small country like the Netherlands (910,000 tonnes of production in 2017). But copying this for China (about 60,000,000 tonnes of production in 2017) would mean a lot (!) of greenhouses.

There is another part of the story that may be subjective, but is part of me as a holobiont: when I think of tomatoes, I always remember some days spent at a friend’s family house somewhere west of Pescara (Italy) at the hillsides of the Abruzzi mountains. They grew their own fruits and vegetables in their garden and, in the summer evenings, we had dinner together outside the house. Part of the dinner was the home-grown tomatoes that were much larger than anything I ever saw before as one tomato slice was as big as my two hands. Coupled with olive oil and sea salt, this was one of the most delicious food I ever came across in my life. This was a tomato from a year when Italy “only” harvested around 52 t/ha. In the same year, the Netherlands was able to produce more than 450 t/ha of tomatoes. I have also eaten a lot of tomatoes from the Netherlands. But not a single one of them was able to evoke such strong (holobiont?) feelings in me like the big Italian tomatoes in my story. So thinking about yield and numbers from the perspective of a holobiont, there is definitely more to food than just “yield optimization”.

But let's come back to our numbers. Another question that we would like to investigate is how the countries with high yields managed to obtain that growth. My guess is that most of them increased use of fertilizers, agrochemicals, or genetically modified crops – which are not sustainable (e.g., we are running out of high concentrated phosphate mines to have sufficient phosphate fertilizers) and whether GM crops are really a “progress” still remains to be seen. After having lived on a farm myself for more than 20 years, I would cast some doubt on this. And whether technology is able to produce the wonderful “tomatoes from the Abruzzes” may also be questioned.

So what do you think? Are we running towards a limit to growth in food? Or am I too skeptical? What is the “price for growth” we are paying or going to pay? As for the latter question, I just would like to point toward the challenge of uranium accumulation in groundwater due to long-term phosphate fertilizer use.

In their 1972 study “Limits to Growth”, Meadows et al. were mainly looking at the accessibility of arable land when thinking about the limits of food production. While this is another major challenge, I think that we should have a look at what we are really doing when “optimizing” yield. All crops have to be grown in soil. And soil is a very complex system, maybe also a holobiont in our understanding. Putting the soil holobiont under permanent and rising stress due to the maximization of one output variable (tonnes of crop per hectare) may not be the wisest way to take care of this system.

  

Acknowledgments: Thorsten wants to thank his students Diana Carrasco and Mirijam Uhland for their contribution to this work.

Forest Recovery: A quote by Anastassia Makarieva

 

You see, there is a succession process for forest recovery. We first have shrub grasses after some disturbance like fire, then it takes time for that to be replaced by trees. So if we are lucky, our grand grandchildren will be walking in such a forest, so this dimension should also be stressed. We are working for the future we are not just securing for ourselves some two dozen years of better comfort. Rather, we send a message through centuries such that people will remember us, and walking into this forest along the brooks and rivers they will remember us with gratitude for our care and dedication.

Anastassia Makarieva  

Can HolobiontsThink?

 

My wife, a holobiont called Grazia, hugs another holobiont, a Cupressus Sempervirens, in the hills near Florence, Italy

This is an excerpt from the chapter I am writing for a multi-author book 

I started this chapter by examining trees and forests as holobionts, then looking at human beings. Trees and humans are as alien to each other as we could possibly imagine. Humans are mobile creatures with an extravagantly powerful metabolism that makes them able to sustain protracted efforts longer than any other living animal. That turbo-charged metabolism is also used to maintain their large brains, of which they are very proud. They use their brains to control their muscles and their sophisticated sensory apparatus, as well as to deal with each other in complicated social rituals.

Trees are the opposite in almost all respects: they are immobile, their metabolism is slow: and they can’t even control their internal temperature. They don’t have eyes, nerves, brains, and not even muscles. Yet, they move, they sense their environment mainly by chemical signals, but also visual and mechanical ones -- including vibrations in the acoustic frequency. They "know" what's going on around them, but in ways that are mostly alien to mobile mammals, including humans.

Nevertheless, humans and trees are both holobionts at their core, and they share more than it would seem at first sight. It is not even forbidden to ask whether trees and other plants might be “conscious” in some way. This is a subject of wide debate, nowadays, and it would be out of the scope of the present text to enter into the details of a question whose answer depends primarily on the definition of the entity being debated. For what we are concerned, we can rather ask the question of whether some creatures store somewhere a schematic representation of at least some elements of the outside world, and modify their behavior depending on the sensor input they receive. That implies a certain level of “consciousness.”

In the case of human beings, there is no doubt that this capability exists. Assuming that most of the readers of this text are human, they should be familiar with the typical sensation of being encased in a bodily container. We have no direct perception of having a brain, but somehow we perceive that we are “inside” a body, that we are a sort of "homunculus" that resides someplace behind the eyes. And, surely, we do keep representations of the outside world, sometimes even too much, as when our political leaders claim that they can “create their own reality.”

How about a tree, then? Where would a tree have its representation of the outside world? As I said, trees have no brains and no nervous system, but they can transmit electric signals from cell to cell. It is a still scarcely known field, but it is known that the phloem and xylem cells form a network to transmit electrical signals long-distance within the plant. At the root level, the mycorrhizal system shares chemical signals within single plants and also from one plant to another. Would such a network be able also of storing information, just like a neural network does in animals? There is no reason to deny that it could. In this case, the representation of the outside world would be stored in the plant as a configuration of the network, continuously changed by sensorial inputs, and leading to signals being transmitted to the various parts of the plants instructing them, for instance, to release volatile organic compounds to fight an insect attack.

If that were the case, apart from the slippery concept of consciousness, a plant would not have the sensation of being encased in a bone cage that humans have. Its intelligence would be delocalized all over the structure. The plant would “feel” the conditions of the leaves, and the presence of sunlight. It would “smell” chemicals floating in the air and perceive the sound of living creatures moving in the vicinity. It would also be actively sending and receiving chemical signals through the mycorrhizal system. In short, it might have a representation of the external world of complexity comparable to the one that humans can build in from their sensorial input. Whether plants could also “create their own reality,” that is, dream, is impossible to say. Communicating with trees is a challenge that was never met, at least in terms compatible with the scientific method. Nevertheless, there seems to be a certain empathy between trees and humans. In the photo, the author’s wife, Grazia, communicates with a specimen of Cupressus sempervirens, in Tuscany.

About this encounter of these two holobionts, we may speculate about their reciprocal sensorial experience. For the human, the tree holobiont is perceived mainly as a visual entity -- but her sensorial system has no capability of detecting the underground root system. Nor she can detect the complex chemical signaling that the tree is operating inside and outside itself. For the tree, instead, the human cannot generate as a visual image, but it is possible that the tree perceives the human from the vibrations she generates and, maybe, detecting the chemical signals she produces. Whether the tree knows that it is being hugged is impossible to say, but we cannot completely discount this possibility. As a further note, both humans and trees use sunlight for chemical processing on their surfaces. Trees use it for photosynthesis, while humans need it to synthesize the compound called "Vitamin D" that they need for their survival.   

We can gather from this discussion that creating a representation of the outside world is a fundamental survival element of holobionts. And since holobionts are the main form that life on Earth takes, we should admit that all holobionts have this kind of capability. In other words, holobionts can “think.” Not in the same way as humans think, of course. But the process of thinking is part of the homeostatic adaptation that all living beings tend to attain. To accomplish that, they need to process information: it is the basic idea of the “dissipation structures” as defined by Prigogine. These structures process entropy and dissipate it, and entropy is basically information. So, holobionts are structured in such a way as to modify their internal structure to obtain homeostasis and maintain it despite changes in the structure of their environment. The holobiont itself is the holobiont’s “brain” and its internal structure stores a representation of the outside world.

Seen in these terms, the hypertrophic brain of which humans are so proud is not an exception to the rule that holobionts store information in their networked structure. All the neurons in the human brain are the same: there is no “super-neuron” that controls the other neurons. In a sense, you could say that the brain is a holobiont, possibly the biggest one known in the ecosystem in terms of the units it contains, with a total of some 86 billion neurons. It is still a small number if compared to the genetic information stored by the whole biosphere has been estimated as Thus, the total amount of genetic information stored in the natural biota is of the order of 1016 bit (Gorshkov et al., 2000) and coincides as an order of magnitude with the information stored in a human brain. This similarity may give us some interesting insights about the idea that the world in which we live is a single, extremely large, holobiont to which we sometimes give the name of Gaia, the Earth Goddess (Castell et al., 2019)