V. Life's Corporeal Evolution Develops, Encodes and Organizes Itself: An Earthtwinian Genesis Synthesis

1. The Origins of Life

Goldford, Joshua, et al. Primitive purine biosynthesis connects ancient geochemistry to modern metabolism. Nature Ecology & Evolution. 8/4, 2024. Blue Marble Space Institute, Seattle, and Earth-Life Science Institute, Tokyo researchers including Harrison Smith sketch out a long feasible course from early precursors all the way present organisms.

An open question in the origin and evolution of life is whether a continuous track from geochemical precursors to the molecular biosphere can be reconstructed from modern biochemistry. Here we identify a pathway by simulating the evolution of a biospheric metabolism via biochemical reactions and models of primitive coenzymes.. This expansion trajectory leads to hypotheses about the tempo and mode pathway of metabolic enhanceent. An evident concordance between biological and geological analyses suggests a plausible evolutionary history for the majority of core biochemistry. (Excerpt)

Greenwell, Chris and Peter Coveney. Layered Double Hydroxide Minerals as Possible Prebiotic Information Storage and Transfer Compounds. Origins of Life and Evolution of Biospheres. 36/1, 2006. This substrate is suggested as the necessary suitable matrix which not only had the capacity to replicate, but could undergo discrete inherited mutations.

Guttenberg, Nicholas, et al. Selection First Path to the Origin of Life. arXiv:1706.05831. As the quote details, with Nathaniel Virgo, Chris Butch, and Norman Packard, Earth-Life Science Institute, Tokyo Institute of Technology researchers propose a synthesis beyond present models as a better, more integral, way to reconstruct. By their perspective, an informational quality can now be attributed to self-amplifying populations.

We propose an alternative to the prevailing two origin of life narratives, one based on a replicator first hypothesis, and one based on a metabolism first hypothesis. Both hypotheses have known difficulties: All known evolvable molecular replicators such as RNA require complex chemical (enzymatic) machinery for the replication process. Likewise, contemporary cellular metabolisms require several enzymatically catalyzed steps, and it is difficult to identify a non-enzymatic path to their realization. We propose that there must have been precursors to both replication and metabolism that enable a form of selection to take place through action of simple chemical and physical processes. We model a concrete example of such a process, repeated sequestration of binary molecular combinations after exposure to an environment with a broad distribution of chemical components, as might be realized experimentally in a repeated wet-dry cycle. We show that the repeated sequestration dynamics results in a selective amplification of a very small subset of molecular species present in the environment, thus providing a candidate primordial selection process. (Abstract)

Hanczyc, Martin. Metabolism and Motility in Prebiotic Structures. Philosophical Transactions of the Royal Society B. 366/2885, 2011. A paper in an issue on The Chemical Origins of Life and its Early Evolution, see Lilley below. In a similar way as Leroy Cronin (search), a University of Southern Denmark, Center for Fundamental Living Technology, biochemist reports an inherent, persistent tendency of so-called “inorganic” materiality to congeal into vesicular droplets, in some guise as primordial protocells. May thus one add an even earlier stage to animate nature’s sequential nest of dolled-up compartmental cells and multicellular selves, lately reaching us writer and reader. Newly edified by this discovery, may we intentionally continue such communality as “social proto-cells,” of nominal 100 persons, the archetypal human grouping, as Sustainable Ecovillages herein personifies?

Easily accessible, primitive chemical structures produced by self-assembly of hydrophobic substances into oil droplets may result in self-moving agents able to sense their environment and move to avoid equilibrium. These structures would constitute very primitive examples of life on the Earth, even more primitive than simple bilayer vesicle structures. A few examples of simple chemical systems are presented that self-organize to produce oil droplets capable of movement, environment remodelling and primitive chemotaxis. Such motile agents would be capable of finding resources while escaping equilibrium and sustaining themselves through an internal metabolism, thus providing a working chemical model for a possible origin of life. (2885)

Harrison, Stuart, et al. Life as a Guide to Its Own Origins. Harrison, Stuart, et al. Life as a Guide to Its Own Origins. Annual Review. Volume 54, 2023. Centre for Life's Origins and Evolution, University College London biotheorists including Nick Lane at once add new nuances as to how early living systems might have spontaneously come into being, but still do so within a mechanical frame.

The origin of life entails a continuum from prebiotic chemistry to molecular machinery. Using Here we consider how selection could promote increased complexity before replicative genes. Far-from-equilibrium environments such as hydrothermal systems drive reactions between CO2 and H2 that self-organize into protocells and prefigure the universal core of metabolism. Patterns in the genetic code show that genes and proteins arose through direct biophysical interactions between amino acids and nucleotides in this protometabolic network. Random genetic sequences template nonrandom peptides, producing selectable function in growing protocells. (Excerpt)

Hazen, Robert. Genesis: The Scientific Quest for Life’s Origin. Washington, DC: Joseph Henry Press, 2005. A synopsis of this premier perception of an innate gestation is cited in Current Vistas.

Hazen, Robert. Geochemical Origins of Life. Knoll, Andrew, et al, eds. Fundamentals of Geobiology. New York: Wiley-Blackwell, 2012. In a volume reviewed more in A Living Planet, the Carnegie Institution of Washington geochemist and author proposes, from this vista, that a “progressive sequence” from physical matter to organic entities can be attributed to the innate action of self-organizing, complex adaptive systems. By these lights, the “emergence of natural selection” occurs quite after and ancillary to this vitalizing force. The chapter concludes by saying such an inclusive synthesis can settle the current metabolism or replication first argument, as the second quotes cites.

Emergence as a Unifying Concept in Origins Research Life’s origins can be modeled as a sequence of so-called ‘emergent’ events, each of which added new structure and chemical complexity to the prebiotic Earth. Observations of numerous everyday phenomena reveal that new patterns commonly emerge when energy flows through a collection of many interacting particles. (315) In the words of John Holland….emergent systems display three distinctive characteristics: they arise from the interactions of many ‘agents,’ energy flows through those systems, and they display new patterns or behaviors that are not manifest by the individual agents. (315)

3. Life began as a cooperative chemical phenomenon between metabolism and genetics: A third possible scenario rests on the possibility that neither primitive metabolic cycles (which lack the means of faithful self-replication) nor primitive genetic molecules (which are not very stable and lack a reliable source of chemical energy) could have progressed far by themselves. If, however, a crudely self-replication genetic molecule became attached to a crudely functioning surface-bound metabolic coating, then a kind of cooperative chemistry might have kicked in. (328)

Hazen, Robert. The Emergence of Patterning in Life’s Origin and Evolution. International Journal of Developmental Biology. 53/5-6, 2009. An update by a prime contributor to the revolution that the universe is not alien to or bereft of life, but rather an ordained nature seems made to generate complex viable systems. In so doing, generic complex, self-organizing, adaptive systems composed of many agents in informed interrelation are increasingly and robustly found everywhere.

Three principles guide natural pattern formation in both biological and non-living systems: (1) patterns form from interactions of numerous individual particles, or “agents,” such as sand grains, molecules, cells or organisms; (2) assemblages of agents can adopt combinatorially large numbers of different configurations; (3) observed patterns emerge through the selection of highly functional configurations. (683)

Complex patterning is a hallmark of biological systems at every scale, from molecules to cells to organisms to ecosystems. Life’s triumph of order over chaos is the epitome of the more general natural phenomenon of emergent systems, in which numerous components or “agents” respond to their local environments, thus interacting to produce patterns or behaviors not characteristic of individual agents. (683)

Helmbrecht, Vanessa, et al. White and green rust chimneys accumulate RNA in a ferruginous chemical garden. Geobiology. 21/6, 2023. Ludwig-Maximilians University paleo-geoscientists return to thermal vent environs with 2020s analytical techniques to be able to explain how they could be a plausible origin site.

Mechanisms of nucleic acid accumulation were likely critical to life's emergence in the ferruginous oceans of the early Earth. How prebiotic geological settings accumulated nucleic acids from dilute aqueous solutions is poorly understood. We, simulated low-temperature alkaline hydrothermal vents in co-precipitation experiments to investigate chemical gardens via sorption. RNA was only extractable from the ferruginous solution in the presence of a phosphate buffer, suggesting RNA in solution was bound to Fe2+ ions. This represents a new mechanism for nucleic acid accumulation in the ferruginous oceans of the early Earth and may have helped to concentrate RNA in a dilute prebiotic ocean.

Hengeveld, Rob, ed. Recent Work on the Origin of Life. Acta Biotheoretica. 55/2, 2007. A special issue of some 225 pages that contains substantial papers such as an “alkaline solution” to life’s start, and how this salient event was bootstrapped upon energy flows.

Herdewijn, Piet and M. Volkan Kisakurek, eds. Origin of Life: Chemical Approach. Weinheim: WILEY-VCH Verlag, 2008. A recent collection from Chemistry & Biodiversity with notable authors such as Christian de Duve and Antonio Lazcano. A good review by Harold Morowitz appears in the March 2009 issue of the Quarterly Review of Biology.

Higgs, Paul. When is a Reaction Network a Metabolism? Criteria for Simple Metabolisms that Support Growth and Division of Protocells. Life. 11/9, 2021. In a paper for a special Prebiotic Systems Chemistry issue, the McMaster University, Ontario biochemist (search) continues his project to reconstruct and explain how living systems came to form, develop and evolve eons ago. Something was going on by itself, which is becoming intelligible to an individual and global collaboration. One wonders by what sufficient veracity might it dawn that a greater phenomenal genesis from which we arise exists on its independent own.

As a way to better understand the nature of metabolism in the first cells, and life’s metabolic origin, we propose three criteria that a chemical reaction must satisfy to sustain the growth and division of a protocell. (1) Biomolecules produced by the reaction system must be at high concentration inside the cell while they remain at low or zero on the outside. (2) The solute concentration inside the cell must be higher than outside. (3) These criteria can be met if the reaction system is bistable, because different concentrations can exist inside and out while all the reactions are the same. (Abstract excerpt)

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