VI. Earth Life Emergence: Development of Body, Brain, Selves and Societies

2. The Origins of Life

Camprubi, Eloi, et al. The Emergence of Life. Space Science Reviews. 215/56, 2019. Eight researchers posted in the Netherlands, France, and the USA including Frances Westall and Michael Russell provide a comprehensive illustrated survey to date of both Earthly and astronomic environs such as watery moons, along with candidate RNA, geologic surface, first prokaryote and other aspects as they may have served to foster our late sentience and present reconstructive vista.

The aim of this article is to provide an overview of possible scenarios for the emergence of life, to critically assess them and to analyze whether similar processes could have been conducive to independent origins of life on the several icy moons of the Solar System. Instead of proposing an unequivocal cradle of life on Earth, we describe the different requirements that seem to be needed for the transition between non-life to life from geological, biological, and chemical perspectives in an integrative manner. Based on the conclusions extracted, we address whether the conditions for abiogenesis are/were met in any of the oceanic moons. (Abstract excerpt)

Cardoso, Silvana, et al. Chemobrionics: From Self-Assembled Material Architectures to the Origin of Life. Artificial Life. 26/3, 2020. Eleven systems biochemists from the UK, Scotland, Spain, Czech Republic, Belgium, Portugal, Hungary, and Italy including Julyan Cartwright, Leroy Cronin, and Michael Russell (search each) contribute to ever-increasing realizations of an innately fertile, life-bearing ecosmic genesis due to such innate properties. As a result, a generative inherency and consequent vital development is being found at procreative effect wherever organically conducive.

Self-organizing precipitation processes, such as chemical gardens forming biomimetic micro- and nanotubular forms, offer much potential to help explore, quantify, and understand nonequilibrium physicochemical systems with regard to life's original emergence. Advances in this area require a combination of expertise in physics, chemistry, mathematical modeling, biology, and nanoengineering, as well as in nonlinear complex systems and materials sciences, giving rise to this new synergistic discipline of chemobrionics. (Abstract excerpt)

It is today commonly accepted that self-assembly is an excellent way to form complex structures in an evolving series of small steps. Indeed, it is the foundation for much of modern nanoscience. Yet nature applies not only self-assembly, but also self-organization, which allows the stepwise building of complex patterns ultimately from simple building blocks. (316)

Cornish-Bowden, Athel and Maria Luz Cardenas. Contrasting Theories of Life: Historical Context, Current Theories. Biosystems. November, 2019. CRNS, University of Marseilles biochemists post a 64 page synoptic review of prior conceptions about how life came to be, evolve and develop. The integral (all male) survey runs from Aristotle to Stuart Kauffman and Karl Friston, with extra time given to Manfred Eigen, Robert Rosen, and Francisco Varela. A steady implication is that some manner of autocatalytic, self-making optimization process is going on.

Most attempts to define life have been individual opinions, but here we compare all of the major current theories. We begin by asking how we know that an entity is alive, and continue by way of the contributions of La Mettrie, Burke, Leduc, Herrera, Bahadur, D’Arcy Thompson and, especially Schrödinger, whose book What is Life? is a vital starting point. All of these incorporate the idea of circularity, but fail to take account of metabolic regulation. In a final section we study the extent to which each of the current theories can aid the search for a more complete theory of life, and explain the characteristics of metabolic control analysis essential for an adequate understanding of organisms. (Abstract)

Cornish-Bowden, Athol and Maria Luz Cardenas. Self-Organization at the Origin of Life. Journal of Theoretical Biology. 252/411, 2008. Researchers at the Institut de Biologie Structurale et Microbiologie, Marseilles, France expand upon Robert Rosen’s 1990s advocacy of “invariant metabolic closure” or “metabolism-replacement systems,” akin to Maturana and Varela’s autopoiesis, to both set aside machine metaphors and stress how life can be seen to organize itself from an earliest occasion. By way of an update, the authors add that a sense of cellular and organismic “identity” ought to be included. (Autopoietic living systems likewise cite an “individuality.”)

Coveney, Peter, et al. Theory, Modelling and Simulation in Origin of Life Studies. Chemical Society Reviews. 41/5430, 2012. In a special section on “Prebiotic Chemistry,” Coveney, and Jacob Swadling, University College London computational chemists, Jonathan Wattis, University of Nottingham mathematician, and Christopher Greenwell, Durham University earth scientist review past and further orientations for this broad, significant field. Beyond vying schools of replication or metabolism, it is advised that an intrinsic self-organization ought to be equally factored in as an original driving source. By virtue of their nonlinear iterative dynamics, a novel, improved understanding of how living systems got going can accrue. Having followed this field since the 1970s, one gets a sense of a new integral phase at last coming together with these theoretical lineaments. See also in this issue, for example, Out of Fuzzy Chemistry: From Prebiotic Chemistry to Metabolic Networks by Juli Pereto.

Origins of life studies represent an exciting and highly multidisciplinary research field. In this review we focus on the contributions made by theory, modelling and simulation to addressing fundamental issues in the domain and the advances these approaches have helped to make in the field. Theoretical approaches will continue to make a major impact at the “systems chemistry” level based on the analysis of the remarkable properties of nonlinear catalytic chemical reaction networks, which arise due to the auto-catalytic and cross-catalytic nature of so many of the putative processes associated with self-replication and self-reproduction. In this way, we describe inter alia nonlinear kinetic models of RNA replication within a primordial Darwinian soup, the origins of homochirality and homochiral polymerization. We then discuss state-of-the-art computationally-based molecular modelling techniques that are currently being deployed to investigate various scenarios relevant to the origins of life. (Abstract)

It is important to begin by scotching a nugatory argument that has been articulated surprisingly often by members of the origins of life community. This argument goes along the lines that the probability of synthesizing a mere gram of the ‘one’ (or a few) particular self-reproducing sequences by a random assembly process would need more mass of substance than exists in its totality on Earth, so cannot have happened. This argument is based on the naïve notion that RNA sequences in a soup form by random synthesis (i.e. as if at equilibrium) and entirely ignores the nonlinear nature of their dynamical self-assembly. (5431) Life is indeed driven by a set of chemical processes taking place from equilibrium. (Coveney cites his prior books and articles, search) To maintain these processes, all organisms are open systems; their complexity is founded on feedback involving autocatalytic and cross catalytic molecules that assist reactions without being destroyed in the process. One metabolic or regulatory pathway may produce a molecule that accelerates other pathways which through a vast among of interlinked chemistry, may end up indirectly catalyzing the original pathway. (5431)

In this review, we have discussed chemical kinetic and molecular modeling approaches that are now throwing very considerable light on numerous challenging issues associated with the origin of life on Earth (and probably elsewhere in the Universe). The methods….span a host of length and time scales, from the quantum mechanical description of electron dynamics, through the atomistic and molecular levels which are described most often by classical mechanics, to more mesoscopic and macroscopic levels which represent the collective kinetic behavior of much larger assemblies of reacting and self-reproducing molecules. (5344)

Cronin, Leroy and Sara Imari Walker. Beyond Prebiotic Chemistry. Science. 352/1174, 2016. A University of Glasgow chemist and Arizona State University astrophysicist contribute to the nascent revolution in origin of life studies, akin to other fields such as genomics, that after a long period of identifying elemental pieces like rudimentary RNA, a presence of equally real dynamic networks which serve to organize and vitalize need be factored in. This advance to join components and connections, along with their informational content, augurs for finding “universal laws of life.” Search for the Philippe Nghe, et al paper Prebiotic Network Evolution for another example.

How can matter transition from the nonliving to the living state? The answer is essential for understanding the origin of life on Earth and for identifying promising targets in the search for life on other planets. Most studies have focused on the likely chemistry of RNA (1), protein (2), lipid, or metabolic “worlds” (3), and autocatalytic sets (4), including attempts to make life in the lab. But these efforts may be too narrowly focused on the biochemistry of life as we know it today. A radical rethink is necessary, one that explores not just plausible chemical scenarios but also new physical processes and driving forces. Such investigations could lead to a physical understanding not only of the origin of life but also of life itself, as well as to new tools for designing artificial biology. (Summary)

Danger, Gregiore, et al. On the Conditions for Mimicking Natural Selection in Chemical Systems. Nature Reviews Chenistry. 4/102, 2020. Aix-Marseille Universite, CNRS physical chemists including Robert Pascal provide a latest contribution to an integral synthesis of substantial, self-organizing agencies with nature’s winnowing optimization processes from many variant candidates. An array of ensuing biomolecular constraints then need be factored into origin of life scenarios.

The emergence of natural selection which requires that reproducing entities have variations that may be inherited and passed on, was an important breakthrough in the self-organization of life. In this Perspective, the assumptions about biological reproduction are confronted with known physico-chemical principles that control the evolution of material systems. Here we see that chemical replicators can behave in a similar fashion to living entities, provided that the reproduction cycle proceeds in a unidirectional way. For this to be the case, the system must be held far from equilibrium and fed with a non-degraded (low-entropy) form of energy. (Abstract excerpt)

Davies, Paul. Quantum Mechanics and the Origin of Life. Norris, Ray and Stootman, Frank, eds. Bioastronomy 2002: Life Among the Stars. San Francisco: Astronomical Society of the Pacific, 2004. Cosmologist Davies notes that as a bio-friendly universe is increasingly recognized, a sufficient explanation for its evolving life may involve and require quantum properties such as superposition and entanglement, which can give rise to a meaningful semantics. See also Davies' popular update "The Ascent of Life" in the New Scientist for December 11, 2004.

In this paper I conjecture that life, defined as an information processing and replicating system, may be exploiting the considerable efficiency advantages offered by quantum computation, and that quantum information processing may dramatically shorten the odds for life originating from a random chemical soup. (237)

Davies, Paul. The Fifth Miracle. New York: Simon & Schuster, 1999. Research on the advent of life has lately matured to a point where an overall review can connect this event with the elemental properties of the universe. The phenomena of self-organization and informed complex systems are seen to imply emergent life is a natural, intended presence. Davies goes on to say that we seem on the verge of a grand shift from an older comatose cosmos to an organic universe presently giving birth to its sentient human phase.

The search for life elsewhere in the universe is therefore the testing ground for two diametrically opposed world-views. On one side is orthodox science, with its nihilistic philosophy of the pointless universe, of impersonal laws oblivious of ends, a cosmos in which life and mind, science and art, hope and fear are but fluky incidental embellishments on a tapestry of irreversible cosmic corruption. On the other, there is an alternative view, undeniably romantic but perhaps true nevertheless, the vision of a self-organizing and self-complexifying universe, governed by ingenious laws that encourage matter to evolve towards life and consciousness. A universe in which the emergence of thinking beings is a fundamental and integral part of the overall scheme of things. (272-73)

De Duve, Christian. Singularities: Landmarks on the Pathways of Life. New York: Columbia University Press, 2005. The Nobel laureate biochemist explains the latest findings on life’s origin, which are seen mostly as an inevitable result of “deterministic” physical-chemical propensities. Multicellular flora and fauna arose from singular phenomena such as a common ancestor for nucleated, eukaryotic cells, and as offshoots of a single founding organism

de Duve, Christian. Vital Dust. New York: Basic Books, 1995. Noted elsewhere, the book is an authoritative exposition of the sequential Ages of Chemistry, Information, Protocells, Single Cell, Multicellular Organisms from which arises Mind and Humankind. And all this is seen to occur due to ingrained laws and properties.

De la Escosura, Andres. The Informational Substrate of Chemical Evolution. Life. Online August 8, 2019. A Universidad Autonoma of Madrid chemist group leader (search) contributes to “abiogenesis” studies, aka how could living organisms have arisen from seemingly inanimate or inorganic substrates, via novel perceptions that precursor biochemistries can similarly be understood to possess a semantic communicative quality. In regard, this earlier material phase or stage can thus accrue an inherent, lively genetic-like content. See also Permeability-driven Selection in a Semi-empirical Protocell Model: The Roots of Prebiotic Systems Evolution by Gabriel Piedrafita, et al in Nature Scientific Reports (7/3141, 2017) for a companion Spanish study.

A key aspect of biological evolution is the capacity of living systems to process information coded in DNA. The overall picture indicates that information processing in cells occurs through a hierarchy of genes regulating other genes through metabolic networks. There is an implicit semiotic character based on functional molecules that act as signs to self-regulate the whole network. In contrast to cells, chemical systems not seen as able to process information, yet they have preceded biological organisms, and evolved into them. Hence, there must have been prebiotic molecular assemblies that could regulate their constituent reactions and supramolecular organization processes. This essay will consider distinctive features of information in living and non-living matter, and how the capacity of biological information processing might be rooted in an autonomous chemical system which could self-sustain and reproduce through organizational closure. (Abstract)

Previous   1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10  Next  [More Pages]