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The Emergence of Self- Rectification Why Self-Organization Can’T Explain the Origins of Life

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The Emergence of Self- Rectification Why Self-Organization Can’T Explain the Origins of Life The emergence of self- rectification Why self-organization can’t explain the origins of life Terrence W. Deacon U C Berkeley A lecture presented Nov. 24, 2014 to the Origins Institute, McMaster University, Ontario, CA Abstract: In many fields it is now common to hear the concepts of emergence and self-organization treated synonymously and for theorists to claim that self-organization explains the emergence of the special properties exhibited by organisms and experienced by conscious beings. In this presentation I will show why this is insufficient—though relevant—for explaining the emergence of these phenomena. I will offer a critique of current mathematical and biochemical approaches to the origins of life that focus on the self- organizing or replicative functions of life as primary, respectively. The key missing step is to show how systems of linked self-organizing processes can potentiate and limit one another in a way that creates substrate-transferrable formal constraints that channel work to prevent their own degradation and error accumulation. This perspective can radically enlarge the domain we define as alive and it suggests very different contexts for its origin. Thinking outside the (reductionisticRNA-world,RNA-world, earth-life) box DNA,DNA, cells,cells, water,water, self-organization,self-organization, replication,replication, naturalnatural selection,selection, ...... Is there a general biology that can ground astrobiological research? Explaining life’s “special powers” •In the closing line of On the Origin of Species, Darwin cryptically acknowledges that the process of natural selection is insufficient to explain life’s core attributes. •Thus he begins the poetic last line with: • "There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or into one...." •Natural selection doesn’t explain the origin of the “special powers” that make life and evolution possible. •They are its necessary initial and supportive conditions. •Life’s special powers didn’t evolve from non-life, they emerged—a different process that evolution depends on. A ‘chicken and egg’ paradox • “If metabolism is dominated mostly by proteins, but is a prerequisite for the functioning of nucleic acid information molecules, how can a system like our current living cell, even the simplest prokaryote, with each of these two parts totally dependent upon the other, ever have evolved in the first place?” — James Strick, 2003 Can a simple solution beat entropy?! • Since it occurred spontaneously the origin of life involved 1. a fairly simple molecular system producing 2. a highly improbable thermodynamic process that locally compensates for entropy increase 3. by organizing chemical work to continually repair locally accumulated thermodynamic damage/error The reverse engineering strategy Tibor Ganti’s Chemoton (1971) Maximally reduced cell i m c i = information, m = metabolism, c = cellular containment Pursuing a “minimal cell” approach to the origin of life does not simplify far enough to explain its spontaneous origin. As a result it leaves unexplained the origin of a vast number of distinct types of molecules and their coincidental synergistic interrelationships. Protocells or frankencells? Simulating original life-forms by recombining components extracted from once-living cells to see if they “reanimate” Can we assume that the first steps toward life involved the same sorts of molecules currently comprising living cells? Doesn’t this sneak in the products of 3.5 billion years of evolution? Logical requirement approaches E. Schrödinger: A self- reproducing automaton? negentropy + reproduces itself including this capacity! information Self-! S. Kauffman: Universal! description! construction! replication + mechanism! Assembly! work cycle instructions! T. Ganti: A! S! (Energy for! S! information + construction)! U! M! (Raw materials)! E! metabolism + D! container after John von Neumann Dawkins, Woese: J. von Neumann: self-description + naked replicator assembly instructions + assembler (molecule as both A-Life & cellular automata: pattern template & catalyst) replication with selection Autocatalysis: molecular self-organization • To be alive an organism doesn’t have to reproduce another organism, but it must continually reproduce those aspects of its material and formal constitution that are continually degraded by the very thermodynamic processes that make its existence possible. • This requires continual chemical work. • Differential replication of molecules can only contribute to the processes of living and evolving if this also includes the linked replication of the system that performs the chemical work required to accomplish molecular replication. • The reciprocal catalysis of an autocatalytic set of molecules accomplishes this via circular catalytic closure Reciprocal catalysis (autocatalytic set) Lysis of molecule a Reciprocal catalysis occurs when into molecules b and one catalytic reaction produces a c by catalyst e product that catalyzes a second releases the energy reaction which produces a of the broken product that catalyzes the first covalent bonds (and may involve multiple steps) Hypercycles: synergies between autocatalytic components Although hypercycles increase the replication rate of their member molecules they are intrinsically unstable with respect to resources (weakest link problem), mutation, and openness to variants. Variants that differentially increase rates of the E>A reaction can degrade the whole cycle by changing the parameters of the A>B reaction (B). And variants of A that also catalyze D can short circuit the whole cycle (C). So there is no source of systemic integrity to prevent degradation of the synergy of catalytic closure. Self-organized dynamics can multiply Hypercyclic interactions can self-organize 4 part autocatalytic hypercycle comprised of Networks of autocatalytic sets exhibit two reciprocally catalyzing peptides which differential growth of subsets due to outcompetes any one autocatalytic set for numbers of linked catalytic interactions substrates. (Lee et al. 1997) between sets. (Hordijk et al. 2014) Kant: the self-forming power of organisms vs mechanism “... a machine has solely motive power, whereas an organized being possesses inherent formative power, and such, moreover, as it can impart to material devoid of it — material which it organizes. This, therefore, is a self-propagating formative power ...” “... in which, every part is reciprocally both end and means.” — Immanuel Kant, 1790 His conclusion: Reciprocal co-production resembles teleology but there is nothing for the sake of which it’s an end; i.e. function is in the eye of the beholder. Autopoiesis (= “self-fabrication”) — Francisco Varela Autopoiesis describes waste what must be true of an molecular metabolic organism without components reaction network explaining how it can be produces accomplished. generates determines Like Kant’s account it resources lacks an account of what self- maintains its systemic bounded system integrity and unity. 25% Only in the mind of the beholder • The property we recognize as autocatalytic synergy in these cases is not an intrinsic property of these molecules but is only a feature attributed to them by an observer reflecting on their interrelations. • These molecular components are each independent structures and not intrinsically linked to one another but are free to diffuse away from one another without interaction. • Their reciprocity and synergy only exist as a categorical judgment in the mind of the beholder. • So their reciprocal synergy is not produced, reproduced, or in any way persistent because it has no ontological status except as a mental category, as Kant recognized over 200 years ago. Morphodynamics (“self-organization”) Rayliegh-Benárd convection cell formation in a dish with a thin layer of constantly heated oil. [a d] pattern of fluid movement creating a convection cell Note: It takes time for a morphodynamic attractor to form under the influence of constant extrinsic disturbance. Maximum entropy production (MEP) Self-organizing processes develop in persistent far-from- Rayliegh- equilibrium conditions . Benárd convection Persistent perturbation induces amplification and propagation of constraints that align dynamics Vortex with minimal total dissipation- formation path length. in fluids Thus minimizing work and maximizing entropy production. Self-organized processes are special converging types of non- Snow linear dynamical processes crystal which can become unstable and growth chaotic if conditions change. Self-organization versus Life Physical systems self-organize because this more efficiently eliminates the conditions that enable them, i.e. organized to be more efficiently self-eliminating. For this reason self-organization (morphodynamics) cannot provide an adequate explanation for the dynamics of life, which must be specifically organized to prevent spontaneous self-destruction and maintain extrinsic support. Paradox: Living systems must depend on morphodynamic processes to generate the constraints required to channel the work that maintains the order that constitutes system unity, and yet must prevent these processes from undermining the very conditions they depend on for their persistence. Organisms rely on self-organization for constraint generation yet invert its logic Organisms perform work to generate and maintain critical constraints against thermodynamic decay. Organisms depend on and utilize energetic and/or material gradients in
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