VI. Earth Life Emergence: Development of Body, Brain, Selves and Societies
2. The Origins of Life
Preiner, Martina, et al. The Future of Origin of Life Research: Bridging Decades Old-Divisions. Life. 10/3, 2020. This is a conference summary by twenty five “early career” scientists as a unique retrospect of this field over its past decades, so that an integrative resolve going forward can be scoped out. The overview allows prior aspects such as prebiotic catalysis, thermal sea vents, mineral surfaces, first replicators, encapsulations, some 21 in all, to be gathered into a graphic display. A further issue has been a broad split between an RNA replicator or bounded metabolism preference, see Iris Fry 2011 herein. New synoptic pathways will involve better theories, common trends, and clever experiment. In this regard, this intentional project is a good example of an intentional shift to a coordinated, worldwide scientific pursuit.
Research on the origin of life is highly heterogeneous. After a peculiar historical development, it still includes strongly opposed views which potentially hinder progress. In the 1st Interdisciplinary Origin of Life Meeting, early-career researchers gathered to explore the commonalities between theories and approaches, critical divergence points, and expectations for the future. We find that even though classical approaches and theories—e.g. bottom-up and top-down, RNA world vs. metabolism-first—have been prevalent in origin of life research, they are ceasing to be mutually exclusive and they can and should feed integrating approaches. Here we focus on pressing questions and recent developments that bridge the classical disciplines and approaches, and highlight expectations for future endeavours in origin of life research. (Abstract)
Prosdocimi, Francisco, et al. The Theory of Chemical Symbiosis: A Margulian View for the Original Emergence of Biological Systems. Acta Biotheoretica. August, 2020. Universidade Federal do Rio de Janeiro, Universidad Nacional Autónoma de México, and Universidade Federal da Paraíba theoretical biologists proceed to expand the occurrence of mutually beneficial symbiotic unions, as long advocated by Lynn Margulis (1938-2011) and now well proven, deeply into life’s prior biochemical beginnings. So into 2020, along with self-organization and networking phenomena, still another innately procreative agency can be found at constant effect at each and every lively stage.
The theory of chemical symbiosis (TCS) suggests that biological systems started with the collaboration of two polymeric molecules existing in early Earth: nucleic acids and peptides. Chemical symbiosis emerged when RNA-like nucleic acid polymers happened to fold into 3D structures capable of binding amino acids together. TCS suggests that there is no chicken-and-egg problem into the emergence of biological systems as RNAs and peptides were of equal importance to the origin of life. Life has initially emerged when these two macromolecules started to interact in molecular symbiosis. Further, we suggest that life evolved into progenotes and cells due to new layers of symbiosis. Mutualism is the strongest force in biology, capable to create novelties by emergent principles; on which the whole is bigger than the sum of the parts. TCS aims to apply the Margulian view of biology into the origins of life field. (Abstract excerpt)
Ranjan, Sukrit, et al. Atmospheric Constraints on the Surface UV Environment of Mars at 3.9 Ga Relevant to Prebiotic Chemistry. arXiv:1701.01373. Harvard University astrobiologists including Dimitar Sasselov quantify how billions of years ago, organic precursors could have formed on a Mars, which was back then a conducive planet, which raises the possibility that this fertility served to seed the presence of living systems on an early Earth.
Recent findings suggest Mars may have been a clement environment for the emergence of life, and may even have compared favorably to Earth in this regard. These findings have revived interest in the hypothesis that prebiotically important molecules or even nascent life may have formed on Mars and been transferred to Earth. UV light plays a key role in prebiotic chemistry. Characterizing the early Martian surface UV environment is key to understanding how Mars compares to Earth as a venue for prebiotic chemistry. (Abstract)
Rasmussen, Steen, et al. Transitions from Nonliving to Living Matter. Science. 303/963, 2004. A report on two international workshops at the Santa Fe Institute and Los Alamos National Laboratory to review the status of artificial life and protocell research.
Although the definition of life is notoriously controversial, there is general agreement that a localized molecular assemblage should be considered alive if it continually regenerates itself, replicates itself, and is capable of evolving. (963)
Rasmussen, Steen, et al, eds. Protocells: Bridging Nonliving and Living Matter. Cambridge: MIT Press, 2009. After years in quest of a scientific ability to create a synthetic, animate, minimal cell in a laboratory, a confluence of researchers felt the project was sufficiently robust for a book treatment. Co-editors Mark Bedau, Liaohai Chen, David Deamer, David Krakauer, Norman Packard, and Peter Stadler, along with 83 authors, flesh out its broad, fluid progress and international venue. A basic definition of life in its archetypal cellular form is closed upon, as the quote avers. In addition to the triade of physiology, genotype, and a bounded vesicle, ancillary attributes are said to be self-organization, relative autonomy, cognitive sensitivity, and a modicum of purposeful behavior. But a penchant for machine metaphors persists, since it is not addressed as to what kind of universe would engender increasingly complex and conscious entities, whom at some late, revolutionary stage might take up and over such organic creation. See also Eric Smith, et al for a typical paper that notes an endemic viability, but again in mechanical terms.
In this book a living system is operationally defined as a system that integrates three critical functionalities. First, it maintains an identity over time by localizing all its components. Second, it uses free energy from its environment to digest environmental resources in order to maintain itself, grow, and ultimately reproduce. Third, these processes are under the control of inheritable information that can be modified during reproduction. (xiii) The book generally reflects the perspective that chemical instances of such forms of life much embody the three operational functionalities in three integrated chemical systems: a metabolism that extracts usable energy and resources from the environment, genes that chemically realize informational control of living functionalities, and a container that keeps them all together. (xiii)
Ricardo, Alonso and Jack Szostak. Life on Earth. Scientific American. September, 2009. A popular article on the RNA first school, recently boosted by John Sutherland’s lab at the University of Manchester which figured out how such precursors could have initially arisen from “inanimate” substrates. But we wish to highlight an excessive use of machine metaphors to describe cellular life. This deep flaw burdens our thinking today, for the model gets everything wrong.
Every living cell, even the simplest bacterium, teems with molecular contraptions that would be the envy of any nanotechnologist. As they incessantly shake or spin or crawl around the cell, these machines cut, paste and copy genetic molecules, shuttle nutrients around or turn them into energy, build and repair cellular membranes, relay mechanical, chemical or electrical messages—the list goes on and on, and new discoveries add to it all the time. It is virtually impossible to imagine how a cell’s machines, which are mostly protein-based catalysts called enzymes, could have formed spontaneously as life first arose from nonliving matter around 3.7 billion years ago. (54)
Rizzotti, Martino, ed. Defining Life. Padova, Italy: University of Padova Press, 1996. In this collection many origin of life researchers attempt to convey its essence by noting various energetic, dynamical, autopoietic, reproductive, self-organizing, and informative qualities.
Ross, David and David Deamer. Dry/Wet Cycling and the Thermodynamics and Kinetics of Prebiotic Polymer Synthesis. Life. Online July, 2016. We cite this entry by an SRI International researcher and the senior UC Santa Cruz biochemist for itself, and to record the Emergence of Life: From Chemical Origins to Synthetic Biology issue, edited by Pier Luigi Luisi, which it is included in. See also therein The Role of Lipid Membranes in Life’s Origin by Deamer and Coevolution Theory of the Genetic Code by Tze-Fei Wong, et al. Some other special collections on this open site are The Landscape of the Emergence of Life, The Origin and Evolution of the Genetic Code, and The Origins and Early Evolution of RNA.
Ruelle, David. The Origin of Life Seen From the Point of View of Non-Equilibrium Statistical Mechanics. arXiv:1701.08388. The Rutgers University mathematician has been a pioneer systems theorist since the 1960s and was co-coiner with Floris Takens (1940-2010) of the widely used phrase strange attractor. This latest note seeks to clarify earlier thermodynamic versions of this approach by noting new work by Gavin Crooks, Christopher Jarzynski and Jeremy England (search each). It then proposes a series of steps by which living systems may arise from this conducive, natural environment. An evident surmise, if to admit, is an innately conducive, life entailing, genesis cosmos.
The purpose of the present note is to attempt a more precise discussion of the above remarks by using basic ideas of non-equilibrium statistical mechanics. In view of this we have just presented some accepted or acceptable ideas on pre-biological or pre-metabolic systems. Note that one such system may occupy several distinct regions of space (just as biological species may consist of different individuals). But pre-metabolic systems have a discrete structure: we are not thinking of a homogeneous pre-biological soup. (4)
Ruiz-Mirazo, Kepa and Alvaro Moreno. Reflections on the Origin of Life: More than an “Evolutionary” Problem. Metode Science Studies. Volume 6, 2016. In this University of Valencia online journal, University of the Basque Country researchers in the Science Philosophy and Logic group and Biology Philosophy Cognition group (which AM founded) pick up on Thomas Nagel’s 2012 work Mind and Cosmos which contends that a mechanist evolution by selection alone misses a key mental, generative feature. In regard, an evident need for a prior source force is specified as nature’s physical (lawful) propensity to organize into emergent, self-sustained scales of complexity and consciousness. As a result, the article achieves one of the clearest and most strident inclusions of (essentially) a natural genetic code. See also Chemical Roots of Biological Evolution by K. Ruiz-Mirazo, et al in Open Biology (April 2017, herein).
This paper argues that the question of the origin of life cannot be explained by appealing exclusively to Darwinian evolutionary mechanisms, as many experts tend to assume, but requires a profound change in perspective. Accordingly, we highlight the fact that, in order to operate as a diversification force (and indirectly, a force for a potential increase in complexity), natural selection requires a number of conditions to be met in order for it to be possible: specifically, self-sustained and self-(re-)productive chemical organisation within a sufficiently large phenotypic space (that is, a wide range of functions). Therefore, we suggest an extension of the self-organising paradigm towards a self-(re-)productive one as an alternative to the main proposals regarding the origin of life, based on molecular populations subject to Darwinian evolution. Such a paradigm would adequately portray the specificity of the biological phenomenon (metabolic and cellular dimensions) and would be relevant before, during, and after natural selection started to operate. (Abstract)
Ruiz-Mirazo, Kepa, et al. Chemical Roots of Biological Evolution: The Origins of Life as a Process of Development of Autonomous Functional Systems. Open Biology. April, 2017. In this Royal Society journal, Spanish astrobiologists K R-M, Carlos Briones and Andres de la Escosura exercise a meld of “systems chemistry with evolutionary theory” along with innate organizational agencies to reach a complete, plausible explanation. A main theme of this extended collegial endeavor is to view life’s oriented development as facilitated by a biochemical autocatalysis toward an enhanced free individuality. As a result, an increasing self control of kinetic, energetic, creative, and spatial dimensions leads to a finesse of the major evolutionary transition scales.
In recent years, an extension of the Darwinian framework is being considered for the study of prebiotic chemical evolution, shifting the attention from homogeneous populations of naked molecular species to populations of heterogeneous, compartmentalized and functionally integrated assemblies of molecules. Several implications of this shift of perspective are analysed in this critical review, both in terms of the individual units, which require an adequate characterization as self-maintaining systems with an internal organization, and also in relation to their collective and long-term evolutionary dynamics, based on competition, collaboration and selection processes among those complex individuals. On these lines, a concrete proposal for the set of molecular control mechanisms that must be coupled to bring about autonomous functional systems, at the interface between chemistry and biology, is provided.
Ruiz-Mirazo, Kepa, et al. Prebiotic Systems Chemistry: New Perspectives for the Origins of Life. Chemical Reviews. 114/1, 2014. Reviewed more Systems Chemistry, Spanish scientists extensively presage a revolutionary genesis cosmos.