Biology of Mind
Part One: Recent Perspectives and Reflections
By Dee Wilson
(Part one of three)
May 20, 2021
These three articles discuss the evolution of mind from single celled bacteria to human consciousness by following the views of four authors, Antonio Damasio, Peter Godfrey- Smith, Merlin Sheldrake and Thomas Nagel. Part 1 describes the precursors of mind in single celled bacteria and in fungi; Part 2 discusses the role of symbiosis and gene transfer in evolution prior to the appearance of animals, the mental abilities of fungi and the development of the unitary awareness of animals. Part 3 discusses the relationship between and among affect, subjectivity and consciousness in animals and humans, and concludes that "affect is to subjectivity as subjectivity is to consciousness," i.e. a means of unifying awareness.
Prior to reading these books, I had become dis-satisfied with recent articles and books regarding consciousness. After the enlightening information regarding advances in neuroscience in Michael Gazzinaga’s book, Who’s In Charge (2011) and Daniel Kahneman’s, Thinking Fast and Slow (2010) which summarized several decades of research in cognitive psychology, subsequent discussions of consciousness by neuroscientists or philosophers I read were turgid, technical and mired in definitional disputes. Neuroscientists and philosophers did not appear to agree on a definition of consciousness, much less on its fundamental elements, or on a research agenda. I ceased reading much on consciousness for a few years.
In 2018, during a reunion with some friends from college we agreed to read and discuss Alva Noe’s book, Out of Our Heads: Why You Are Not Your Brain and Other Lessons from the Biology of Consciousness (2009). I wrote a brief review of Noe’s book ( Appendix 1) in which I endorsed some of his main arguments such as “Maybe consciousness depends on reliable interactions between what is going on in the brain and what is going on in the non-brain parts of the body. It could even turn out that consciousness depends on interactions between brain and the body and bits of the world nearby,” (p.13); and “Consciousness requires the joint operation of brain, body and world.“ (p.10). However, I questioned Noe’s bold assertions that “ … there is no thing inside you that makes you conscious,” ( p. 7) and “ … Brains don’t think … the world shows up thanks to our interactions with it. It is not made in the brain or by the brain.” (p.164)
I concluded that Noe’s book has a partially accurate but inadequate understanding of the function of the human brain, i.e., to guide “dynamic interaction with things around us” ( p. 164) while ignoring or downplaying the integrative function of the brain in self-regulation and in coordinating an enormously complex organism with physical, social and spiritual needs. Noe also underestimates the extent to which the world reflected in consciousness is imagined as well as perceived. It is a gross misrepresentation of both perception and cultural evolution to insist that the world we perceive just “shows up”; and Noe has an inadequate appreciation of internal mental/emotional states because (I believe) he is uncomfortable with the discussion of brain function detached from the external world revealed by the senses or embodied in social interactions.
Noe demolished neuroscientific absurdities such as the human brain in a vat detached from the body only to create others such as the world that “shows up” in conscious awareness absent specific features of brain functioning.
When I finished reading Out of Our Heads, I wanted something different: (1) an account of mind and brain rooted in evolutionary biology; (2) an understanding of mind and consciousness developed bottom up from the simplest organisms to human consciousness; (3) an identification of the elements of mind before nervous systems and brains appeared in animals; (3) an appreciation of the different sensory worlds and (ultimately) experiences of various kinds of animals; (4) a better understanding of how plants and animals are different from each other; (5) a plausible hypothesis regarding how subjectivity and sense of self vs. other was created by evolution. Fortunately, I soon discovered Antonio’s Damasio’s, The Strange Order of Things and Godfrey-Smith’s Metazoa, two outstanding books on the biology of mind whose authors work bottom up ( i.e., one cell organisms to human consciousness) rather than top-down (conscious reflection to animal instinct to sensory awareness, etc.) I began reading Entangled Life while writing this article, a fortunate discovery in that the book addresses major themes developed by Damasio and Godfrey-Smith.
Mind in biology
Several of the capacities of animal minds and of plants discussed by Godfrey – Smith, i.e., sensitivity to the environment, purposeful activity, response to threat, food seeking, cooperation with other organisms of the same type or different species (both individuals and in large groups), learning from experience and use of electrical charge to regulate the boundary between an organism and its external world appeared in one called organisms, well before nervous system, brains or other types of sensory mechanisms utilized by plants and animals. Consider this passage from Damasio’s The Strange Order of Things:
“Social governance has humble beginnings, and neither the minds of Homo sapiens nor of other mammalian species were present at its natural birth. Very simple unicellular organisms relied on chemical molecules to sense and respond, in other words to detect certain conditions in their environments, including the presence of others, and to guide the actions that were needed to organize and maintain their lives in a social environment. … bacteria living in terrain where nutrients are scarce band together in clumps. Bacteria can sense the numbers in the groups they form, and in an unthinking way assess group strength, and they can … engage in a battle for the defense of their territory. They can physically align themselves to form a palisade, and they can secrete molecules that constitute a thin veil, a film that protects the ensemble …” Furthermore, “quorum sensing” is the process that assists bacteria in these adventures. The achievement is so spectacular that it makes one think of capabilities such as feeling, consciousness and reasoned deliberation, except that bacteria do not have any such capabilities; they have the powerful antecedents to those capabilities.” (p. 19)
Damasio argues that “they (bacteria) lack the mental expression of those antecedents,” despite having capabilities that resemble those of social animals. Damasio goes on to explain that “Bacteria are the earliest form of life, dating back to almost four billion years ago. Their body consists of one cell, and the cell does not even have a nucleus. They have no brain. They have no mind in the sense the reader and I do.” ( p. 20)
Nevertheless, “in the complex, albeit un-minded social dynamic they create, bacteria can cooperate with other bacteria. ... And in their un-minded existence it turns out they even assume what can only be called a “moral attitude.” … When bacteria detect “defectors” in their group, which really means that certain members fail to help with the defense effort, they shun them even if they are genomically related and therefore part of their family. Bacteria will not cooperate with kin bacteria that do not pull their weight and help with the group endeavor, in other words they snub noncooperative turncoat behavior. … The variety of possible bacterial “conduct” is remarkable.” (p.20)
Damasio refers to single cell bacteria with these capacities for cooperation and competition that mimic complex social rules as “un-minded”; though it seems apparent that bacteria have incipient minds, i.e., the earliest elements of mental functioning. It is astonishing that “simple bacteria have governed their lives for billions of years according to an automatic schema that foreshadows several behaviors and ideas that humans have used in the construction of cultures.” (p.21) Damasio asserts that “natural selection and genetic transmission have been hard at work in shaping and sculpting such modes of reacting in social environments to construct the scaffolding of the human cultural mind. … the human unconscious literally goes back to early life-forms, deeper and further than Jung or Freud ever dreamed.” (p.22)
The Life of Fungi
Entangled Life: How Fungi Make Our Worlds, Change Our Minds and Shape Our Futures (2020) by Merlin Sheldrake discusses the extraordinary capacities of fungi, which are neither plants or animals, and which have lived on this planet for 1-2 billion years. Fungi have many varied complex relationships with plants and animals. According to Sheldrake, “The ability of fungi to prosper in such a variety of habitats depends on their diverse metabolic properties. Metabolism is the art of chemical transformation. Fungi are metabolic wizards and can explore, scavenge, and salvage ingeniously, their abilities rivalled only by bacteria. … Few environments are too extreme. … The blasted nuclear reactor at Chernobyl is home to a large population of such fungi. A number of these radio-tolerant species even grow toward radioactive “hot” particles; and appear to be able to harness radiation as a source of energy, as plants us the energy in sunlight.” (p. 5)
Sheldrake describes his “growing awareness of the many sophisticated, problem-solving behaviors that have evolved in brainless organisms outside the animal kingdom.” (p.15) Slime molds such as “Physarum polycephalum” “form exploratory networks made of tentacle-like veins and have no central nervous system – nor anything that resembles one. Yet they can “make decisions” by comparing a range of possible courses of actions and can find the shortest path between two points in a labyrinth. (p.15) In ingenious experiments that recreated a model of the Greater Tokyo area in a peri dish using oak flakes to mark major urban hubs, after a day “the slime mold had found the most efficient route between the oats, emanating into a network almost identical to Tokyo’s existing rail network. In similar experiments, slime molds have re-created the motorway network of the United States. (p.15)
Sheldrake states that “Whether one calls slime molds, fungi, and plants “intelligent” depends on one’s point of view;” (pp. 15-16) yet fungi “are capable of sophisticated behaviors that prompt us to think in new ways about what it means for organisms to “solve problems,” “communicate,” “make decisions,” “learn,” and “remember.” (p. 16) At the end of his introductory chapter, Sheldrake comments that “My exploration of the fungal world has made me reexamine much of what I knew. Evolution, ecosystems, individuality, intelligence, life – none are quite what I thought they were. “(p. 23) Ditto for the concept of mind, the earliest astonishing manifestations of which were present in bacteria, other one celled organisms and fungi billions or hundreds of millions of years before animals developed nervous systems and brains.
The mind/brain duality has been misrepresented by philosophers and neuroscientists. The question is not how mind can be described by neuroscientific study of the human brain, or whether hard science should dispense with mental concepts that lack behavioral correlates. Rather, the question for neuroscience is how animals’ nervous systems and brains enhanced sophisticated mental functioning already present in the earliest forms of life on earth. Godfrey-Smith asserts that “We need to continually avoid falling into the habit of thinking that all forms of experience must be human-like in various ways.” (p.18)
The control of electric charge
Nothing about the functioning of single cells is more surprising than the capacity to utilize electrical charge to regulate interactions between cells and their immediate surroundings. Godfrey-Smith asserts that “Charge was tamed billions of years before (technology developed in the 19th century) during early stages of life’s evolution; (p. 28) “in cells and organisms, electricity is the means by which much of what happens is done.” (p. 28) One of the main functions of electric charge in a cell, Godfrey Smith explains, is to regulate movement of materials across the cell’s boundary.
Godfrey- Smith explains: “The background to the evolution of the mind is life itself – not everything about life, not DNA and its workings, but other features. The start is the cell. Early life … was single celled. Animals and plants are huge collaborations of cells. … (p. 26)
“Cells are bounded, with an inside and an outside. The border is a membrane; it partially seals the cell but has channels and ports embedded in it. … inside is a frenzy of activity.” (p.26)
If we imagine a cell full of intricate apparatus, parts with jobs to do, these devices are constantly being bombarded by water molecules. An object in a cell has a fast- moving water molecule collide with it about every ten trillionth of a second. … These collisions are not trivial; each has a force that dwarfs the forces those devices themselves exert. (p.27)
The problem cells have to deal with … is not getting things to happen, but creating order, instituting some rhyme and reason in the spontaneous flow of events.” (p.27)
Godfrey- Smith maintains that “The origin of life occurred fairly early in the history of the earth, perhaps around 3.8 billion years ago, on a planet about 4.5 billion years old. The first life may not have been cell shaped, , but there must have been some initial way for a special set of chemical processes to be contained, marked off, and preventing from diffusing away. Then at some stage there were cells … cells that consistently maintain their organization and reproduce. … As cells acquired the power to keep themselves going – a central achievement was gaining control over charge.” (p. 28)
Godfrey- Smith explains that “Electric charge is a basic feature of matter. Charge can be positive or negative. Objects with the same charge (positive and positive, for example) repel, and those with unlike charges (positive and negative) attract.” (p.29) “And, “Charge is not life-like or mental in itself … But living activity runs on charge, especially by the corralling, pumping, herding, and unleashing of ions. (p. 30). Further, “a cell’s membrane keeps many things either outside or inside, but it contains channels that selectively let some material through. Many of these are ion channels. Sometimes, a channel will passively allow ions to move from one side to the other --- in other cases, the cell pumps the ions across the membrane. (p.30)
“Whenever there is traffic across a living system’s boundaries, … it tends to take on further roles. A flow of ions can function as a minimal form of sensing.” (p. 30)
Before proceeding further, a brief summary may be useful: single celled organisms were either the first form of life; or appeared soon after life was created on Earth about 3.8 billion years ago. A single cell is “a molecular storm, a ceaseless turmoil of collisions, attractions and repulsions.” (p. 27) A cell is sensitive to events and materials at its boundary, and electrical charge is one way that cells regulate traffic across the boundary. Electrical attraction and repulsion at the cellular level begin to resemble sensory activity.
This story of single cells developing the capacity to utilize electrical charge to attract what supports their functioning and to repel what threatened them has another surprising twist. According to Godfrey-Smith, “The next step is excitability … Voltage gated ion channels … open as a response to electrical events that they, the channels are exposed to. This makes possible a chain reaction; a flow of current creates a greater flow of current, one that spreads over the cell membrane. … voltage gated ion channels are the basis for another innovation, the action potential. This is a moving chain reaction of changes to the membrane of a cell, especially in our brain. … A wave of electrical disruption travels along the membrane like a pulse.” (p. 32) And: “In a voltage-gated ion channel, a controller of current is affected by the charges it is exposed to; the flow of current is electrically controlled. “This is the principle of a transistor” (p.32) which was invented by humans in the twentieth century. “The same device was invented billions of years ago in the evolution of bacteria.” (p. 32)
Godfrey Smith asks the question, “If bacteria invented transistors, what were they doing with them?” (p. 32) to which he replies,” As far as I can tell, no answer to this question is widely agreed on. (p. 32) He continues: “Several billion years ago, nature invented the fundamental hardware device in computer technology – a complicated and costly device, too – and did so in bacteria, but bacteria do not seem to have been doing much computing with it. … Regardless of why it arose, the voltage – gated ion channel was a landmark in the taming of charge. These channels do not have a single obvious use … In a sense, neither does a transistor, and in both cases, that is part of their importance. A transistor is a general means for control, a device for making events here affect events there in a reliable, rapid way. … When they enable action potentials, voltage gated ion channels also make it possible for a cell’s activity to have a “digital” quality, a neuron either fires or not, yes or no.” (p.33) Godfrey-Smith concludes with an understatement: “It is remarkable that this control device was invented so far back, when most of the uses it has now were not even glints in evolution’s eye.” (p. 33)
To summarize once more: according to Godfrey-Smith, bacteria developed the capacity to utilize electrical charge to help maintain their physical integrity; and mastered the use of action potentials generated by ion gated voltage channels to control electrical current for purposes biologists do not yet understand or agree on. Bacteria invented a biological version of transistors for no reason that natural selection can yet account for, but which turn out to the basis for the digital way neurons (i.e., fire, don’t fire) operate. It seems that there has to be something missing in this account of the development of electrical action potentials in bacteria.
In this section of Metazoa, Godfrey-Smith emphasizes a point that will be important in understanding the minds of animals, including humans: “A great deal of the activity in a cell is concerned with maintaining itself, keeping energy coming in, keeping a pattern of activity going, despite decay and turnover in materials. ( p. 33) Further, “In cells, the processes of life involve imparting order on a molecular storm and the imperfect herding of ions.” (p. 34) The coordination, integration and regulation of internal processes is a feature of incipient mind in single celled organisms, and in plants and animals. However, Godfrey Smith reminds readers that even in single cells and other early life forms, there is another central feature; “That feature is traffic, a to-and-fro between living systems and their surroundings. … Cells are bounded but they are not closed to the world. I am emphasizing here the windowed character of cellular life. This traffic has a metabolic side- a side that involves getting energy and using it to stay alive – and also an informational side. (pp. 34-35)
Godfrey-Smith refers to the perspective of a colleague, Maureen O’Malley, who emphasizes that “living systems are inherently sensitive to changes and events outside. They don’t have the option of being windowless; but are open to the world out of energetic necessity. … All known cellular life, including tiny bacteria, has some ability to sense the world and respond to it. Sensing, in at least the most basic forms, is ancient and everywhere.” ( p. 35)
Antonio Damasio’s The Strange Order of Things is one of the most important and provocative books published in recent years regarding the origins of life and its early characteristics, the biological foundations of mind, and the development of human consciousness and culture. Damasio is a philosopher who has published books on Descartes and Spinoza, and a neuroscientist who has written extensively about the human brain.
The Strange Order of Things brings together the philosophy of Spinoza with an extraordinary account of homeostasis as the organizing principle for all life on earth. Damasio begins his discussion of homeostasis with the following:
“Homeostasis refers to the fundamental set of operations at the core of life, from the earliest and long vanished point of its beginning in early biochemistry to the present. Homeostasis is the powerful, unthought, unspoken imperative whose discharge implies, for every living organism, small or large, nothing less than enduring and prevailing.” (p. 25) In Damasio’s view, homeostasis is about more than regulating internal chemistry to ensure survival. Rather, “it (homeostasis) ensures that life is regulated within a range that is not just compatible with survival but also conducive to flourishing …” (p.25) and precedes the creation of genes. Damasio maintains that “Homeostasis has been the basis for the value behind natural selection, which in turn favors the genes … The development of the genetic apparatus ... is not conceivable without homeostasis.” (p.26)
Damasio’s argument that early life was created by metabolism, not by genetic material (which is too complex to have assembled itself spontaneously) is provocative but not radical. Damasio estimates the likelihood that life originated in genetic material as “low to nil.” (p.37) Damasio’s views regarding the origins of life “has been persuasively argued by Freeman Dyson and is favored by a number of chemists, physicists and biologists, among them J.S. Haldane, Stuart Kauffman, Keith Baverstock, Christian de Duve and P.L. Luisi.” (p.39)
However, what is radical is Damasio’s discussion of the homeostatic imperative:
“Curiously, on the metabolism- first (before genes) account, homeostasis “tells” the cell … to do its business as perfectly as possible so that the cell’s life can persist. This is the same exhortation that genes are supposed to make to the living cell in the replicator account (of life’s origins) except that the goal of genes is their own persistence, not the cell’s life.” (pp. 39-40) “Well-groomed metabolism – that is metabolism guided by homeostasis – would define the beginnings of life … and be the driving force for evolution.” (p. 41) Damasio hypothesizes (his term) “that the homeostatic imperative, as embodied in the very first life forms, was followed by genetic material, not the other way around.” This would have been achieved “as a result of its constitutive but un-spelled endeavor toward optimization of life … “Genetic material would have assisted the homeostatic imperative by being responsible for the generation of progeny …” (p. 42) Further, “The biological structures and operations responsible for homeostasis embody the biological value on the basis of which natural selection operates.” (p. 43)
To make Damasio’s point more clearly: metabolism led to early life forms that achieved optimal states i.e., “flourishing,” which these life forms, including single cells, sought to sustain by somehow creating genes at the behest of the homeostatic imperative. He states “… it is as if single cells and multi-cellular organisms were striving for a particular class of steady state conducive to flourishing” (p. 45) This idea sounds much like (critics might say “suspiciously like”) a condition of well-being. Damasio continues: “This (homeostasis) is a natural upregulation … aiming at the future of the organism, an inclination to project itself in time by means of optimized life regulation and progeny. “(p. 45)
The dynamic process Damasio describes sounds thoroughly experiential, i.e., single cells achieved optimal states of flourishing, i.e., well-being, which they wanted to continue (the homeostatic imperative), so somehow through “ceaseless activity” genes were created. Regarding the homeostatic imperative, he writes that “The forceful projection into the future was signified by the underlying condition of well- being.” (p. 49) In Damasio’s view, life embodied the homeostatic imperative from its creation, while in animals and humans (he asserts) feelings are “the deputies of homeostasis.” (p.26) “In standard circumstances, feelings tell the mind, without any word being spoken of the good or bad direction of the life process … (p. 12), Damasio asserts.
Damasio’s description of homeostasis in early life forms contains mental concepts in practically every sentence, while his analysis insists that life before plants and animals evolved 600 -700 million years ago was “un-minded.” For example (on p. 35) Damasio asserts that “In brief, each cell manifested, and all cells forever so, a powerful, seemingly indomitable “intention” to maintain itself alive and to sail forth. … Let me stress I do not think cells have intentions, desires, or wills in the same way that minded and conscious beings do, but they can behave as if they did and do. (p. 35) And “This indomitable intention corresponds to the “force” that the philosopher Spinoza intuited and named the conatus. … it is present at the microscopic scale of each living cell …” (p. 35) and leads to “the continuous attempt at achieving a state of positively regulated life … a defining part of our existence “ (p. 46) and is mirrored in human life and societies, i.e., at every scale.
What Damasio appears to be arguing is that homeostatic flourishing is the goal of life, an argument that is anathema to most biologists and many other modern thinkers who believe that evolution through natural selection means that biological life has no other goal than survival and the propagation of genes into the future. Damasio’s argument is that genes operate as they do because life at all levels is capable of “flourishing,” i.e., optimal levels of well-being, and through the homeostatic imperative wants to ensure the propagation of states of well- being into the future.
Putting aside the discussion of homeostatic “intention” and whether evolution has a goal that transcends the transfer of genes from one generation to the next, homeostatic regulation is crucial to maintaining the life of single cells and multi-cellular organisms. Damasio comments that “very few aspects of an organism’s operation escape the obligation to keep themselves in check. Accordingly, the mechanisms of homeostasis were first conceptualized as strictly automatic and pertained only to the state of an organism’s internal environment. “ ( p. 41) This is no easy task given the “molecular storm” that exists in single cells ; nevertheless, Damasio argues that this traditional view of homeostasis is “not sufficiently ample.” (p. 45) “First, the homeostatic process strives for more than mere steady state. …it is as if single cells or multicellular organisms were striving for a particular class of steady state conducive to flourishing. … Second, physiological operations rarely abide by thermostat-like set points. … there are steps along scales that ultimately correspond to the greater or lesser perfection of the regulatory process.” (p.45)
Damasio believes that the capacity of conscious minds to interfere with automatic regulatory mechanisms “and create new forms of life regulation that have the very same goal of basic automated homeostasis,” i.e., “viable upregulated life states that tend to produce flourishing,” (p.46) is a manifestation of homeostasis that leads to human cultures.
Damasio maintains: “Fourth, whether one considers single-celled or multicellular organisms, the essence of homeostasis is the formidable enterprise of managing energy – procuring it, allocating it to critical jobs such as repair, defense, growth and participation in the engendering and maintenance of progeny. This is a monumental endeavor for any organism … “ ( p. 46) Homeostasis, in Damasio’s view, does not emerge from life; it is a part of life itself, already present in single celled organisms that lack nervous systems, and which is also a driving force in cultural evolution. Furthermore, the earliest expression of “automated homeostasis” (Damasio’s term) beginning with bacteria included and in fact required sensing and responding abilities which are precursors to mind “later to be imbued with feelings and consciousness.” (pp. 48-49)
In summary, Damasio’s account of homeostasis begins with the regulation of internal chemical processes necessary to the maintenance of life in single cells, especially the “the transformation of energy sources into energy itself …” Deviations from the required level of certain variables result in disease, and unless a more or less rapid correction occurs, the radical result is death.” (p.50) Effective homeostasis requires learning.
According to Damasio, “Bacteria are very intelligent creatures; that is the only way of saying it, even if their intelligence is not being guided by a mind with feelings and intentions and a conscious point of view. They can sense the conditions of their environment and react in advantageous to the continuation of their lives. … Those reactions include elaborate social behaviors. They can communicate among themselves … the molecules with which they signal speak volumes. … they have varieties of perception, memory, communication, and social governance.” (p. 54) Damasio asserts that bacteria have “intelligence without a brain or mind” that relies on chemical processes and electrical networks “of the sort nervous systems eventually came to possess, advance and explore in later evolution.” (p. 54)
Damasio reminds readers that “Historically, the world of bacteria – cells without nuclei … was followed about 2 billion years later by the far more complicated world of nucleated cells, or eukaryotes. Multi-cellular organisms, or metazoans, came next, 700 to 600 million years ago. “( p. 54) In other words, single-cell bacteria with their extraordinary precursors of mind – or incipient mind in my terminology- were alive on this planet more than 3 billon years before the appearance of plants and animals.
From single cells to nervous systems
This article is about the evolution of mind, i.e., mental abilities, prior to the appearance of plants and animals. Nevertheless, I cannot refrain from asking the question which may occur to readers: what was occurring in the evolution of life between the appearance of single cells 3.8 billion years ago and the development of nucleated cells, i.e., eukaryotes, 2 billion years later? One possible answer is “developing genetic material” per the “metabolism first” account of the origins of life. Perhaps genes were developed in stages, rather than at a point in time, by the “ceaseless activity” of simple life forms which were widespread but could not reproduce. Of course, this is pure speculation.
However, what is less speculative is the development in bacteria of symbiosis, i.e., “the interaction between two different organisms living in close physical proximity, typically to the advantage of both.” (Webster’s Dictionary) Sheldrake offers the following discussion of gene transfer between bacteria:
(Lederberg) “found that bacteria could trade genes with each other. One bacterium could acquire a trait from another bacterium “horizontally.” Characteristics acquired horizontally are those that aren’t inherited “vertically” from one’s parents. … Horizontal gene transfer implied … that branches of the evolutionary tree that had long since diverged were able to converge within the body of a single organism. For bacteria, horizonal gene transfer is the norm – most of the genes in any given bacterium do not share an evolutionary history.” Further, “Over the last few decades it has become clear that bacteria are not alone in this ability. Genetic material has been exchanged horizontally between all domains of life.” (Sheldrake, pp. 77-78)
The hypothesis that evolution occurs through symbiosis as well through advantageous mutations was once strongly opposed by most evolutionary biologists. An American biologist, Lynn Margolis, who proposed this hypothesis was ridiculed by many of her peers. Sheldrake comments: “However, in the 1970’s Margulis was proven correct. New genetic tools revealed that mitochondria and chloroplasts had indeed started off as free-living bacteria. … The endosymbiotic theory … rewrote the history of life.” (Sheldrake, p. 81)
According to Damasio, “The long process of evolution and growth is full of examples of powerful cooperation (s) … bacterial cells cooperate with other cells so as to create the organelles of more complex cells. … The principle is always the same: organisms give up something in exchange for something other organisms can offer them. ... What bacteria, or nucleated cells, or tissues, or organs, give up, in general, is independence; what they get in return is access to “the commons”, the goods that come from a cooperative arrangement in terms of indispensable nutrients or favorable general conditions such as access to oxygen ...” (Damasio, p. 55)
The evolution of mind in single celled bacteria, in nucleated cells (i.e., cells with a nucleus) and in multi-cellular organisms such as fungi occurred in tandem with the development of more complex life forms; and was a response to the increased difficulty of regulating both the internal chemistry and social relationships of these organisms.
Revisiting the mental abilities of fungi
Sheldrake describes the “brain like” capacities of fungi:
“… their many options entail decisions.” (p. 44)
“Their fickle environments entail improvisation.” (p. 44)
“Their trials involve errors,” (p.44) i.e., they learn from experience.
“… fungi actively sense and interpret their worlds … (p. 44)
Fungi can find the shortest path out of a labyrinth. “Solving mazes and complex routing problems are nontrivial exercises. This is why mazes have long been used to assess the problem-solving abilities of many organisms from octopuses to bees to humans.” (p. 48)
“… solving spatial and geometrical problems is what they have evolved to do.” (p. 48)
“… mycelial networks (of fungi) coordinate themselves and behave as an integrated whole,” (p. 49) despite the lack of a center of control such as a brain. (p. 50) “Mycelial coordination takes place both everywhere at once and nowhere in particular. A fragment of a mycelium can regenerate an entire network. (p. 50)
Fungi acquire food through mycelium. “Some organisms – like most animals - find food in the world and put it into their bodies. Fungi have a different strategy. They digest the world where it is and then absorb it into their bodies.” (p. 51) Mycelium acquire food through “a living, growing, opportunistic investigation…. No two mycelial networks are the same.” (p. 51) “Hyphae are sensitive to stimuli, and at any one moment are confronted with a world of possibilities. … hyphae steer themselves toward appealing prospects and away from unappealing ones.” (p.57) “… most fungi are able to detect and respond to light (its direction, intensity or color). … “Hyphae can sense the texture of surfaces” and “fungi maintain countless channels of chemical communication with other organisms and with themselves: when they fuse or have sex hyphae distinguish “self” from “other” and between different kinds of “other.” (p. 58)
As amazing as these abilities are, there is more, according to Sheldrake. “... somehow, hyphae --- piloted by their tips -- are able to integrate these many data streams and determine a suitable trajectory for growth.” (p.58) “A given mycelial network might have anywhere between hundreds and billions of hyphal tips, all integrating and processing information on a massively parallel basis.” ( p. 59)
Sheldrake offers a possible answer for fungi to the question raised by Godfrey- Smith: “if bacteria invented transistors, what were they doing with them? Why did they need to control electricity with electricity?” (p. 32) “… animals aren’t alone in producing action potentials. Plants and algae produce them, and it has been known since the 1970’s that some types of fungi do also. Bacteria, too, are electrically excitable. … and it has been known since 2015 that bacterial colonies can coordinate their activity using action potential – like waves of electrical activity.” (Sheldrake, (pp. 60-61.) Stafen Olsson, a Swedish mycologist, “hypothesized that electrical signaling was a realistic way for a wide variety of fungi to send messages between different parts of themselves, messages that conveyed information about food sources, injury, local conditions within the fungus, or the presence of other individuals around it.” ( p. 62) In other words, in both bacteria and fungi, action potentials and the control of electrical current may be a means of communication among cells in a complex network regarding matters of concern to the whole network.
Sheldrake points out the resemblance of fungal networks that “use waves of electrical activity to transmit signals around a network” (p. 63) to “a brain-like phenomenon.” (p. 63) Andrew Adamatzky, Director of the Unconventional Computing Laboratory, has proposed that fungal networks “compute information encoded in spikes of electrical activity.” (pp. 63-64) According to Sheldrake, “Adamatzky has spent years developing ways to use slime molds as sensors and computers. ... Fungal networks, he reasons, are monitoring a large number of data streams as part of their everyday existence.” (p. 64) However, Sheldrake maintains that “Olsson and Adamatzky have shown mycelium can be electrically sensitive, but they haven’t shown that electrical impulses can link stimulus to a response. … This is a challenge for the future.” (p. 65)
What is mind?
The idea (or assumption) that mental abilities such as sensation, deliberate activity, strategizing and decision making, social cooperation, maintaining a boundary between self and the external world, the ability to learn and improvise, and to communicate within networks and across colonies of cells depend on nervous systems and animal brains is clearly false. Sheldrake comments:
“For many, the brain centric view is too limited. The idea that a neat line can be drawn that separates nonhumans from humans with “real minds” and ”real comprehension” has been curtly dismissed by the philosopher David Denett as … “archaic myth.” Brains didn’t evolve their tricks from scratch and many of their characteristics reflect more ancient processes … Complex information processing is evidently not restricted to the inner workings of brains. … intelligent behaviors can arise without brains. A dynamic and responsive network is all that’s needed.” (pp. 65-66)
Sheldrake argues that “Many types of organisms … have evolved flexible networks to help solve the problems that life presents. Mycelial organisms appear to be some of the first to do so.” (p. 67) Sheldrake asserts that fossilized mycelium with “‘tangled networks” 2.4 billion years old have been discovered in ancient lava flows “more than a billion years before fungi were thought to have branched off the tree of life. … Remarkably unchanged, mycelium has persisted for more than half of the four billion years of life’s history, through countless cataclysms and catastrophic global transformations.” (p. 67) Sheldrake believes that biologists have barely scratched the surface in attempts to understand how mycelial networks work, e.g., how fungal networks integrate massive amounts of data, and utilize electrical messaging to regulate themselves and decide on improvisational strategies for acquiring food.
It would be a large understatement to assert that humans have vastly underestimated the intelligence of early life forms and (of course) of plants and animals as well. One lesson stands out: even single cells have surprising intelligence that mimics the characteristics of human social behavior and which is both multivarious and strange. In every organism, however simple or complex, mental functions have two main goals: (1) regulation of internal chemical processes, and (2) managing social interactions with other organisms of the same type and other types and with the external world, especially at the boundary of the organism.
If (as Damasio believes) at the origin of life metabolism preceded genes, then incipient mind guided by the homeostatic imperative may have participated in the torturous slow assemblage of genetic material which was shared among single cells through endosymbiosis as well as through reproduction.
End of Part One
Part Two will discuss the evolution of mind in plants and animals, beginning with a summary of information from Sheldrake’s Entangled Life regarding symbiotic relationships between - and among - plants and fungi. We also will discuss the development of subjectivity in animals based on Godfrey-Smith’s, Metazoa; and will consider Damasio’s ideas regarding how humans’ feelings reflect the homeostatic imperative, i.e., to “flourish.” I will discuss the integrative functions of consciousness.