VI. Earth Life Emergence: Development of Body, Brain, Selves and Societies
2. The Origins of Life
Russell, Michael. First Life. American Scientist. January-February, 2006. The thermal vents of the Hadean seas indeed served as incubators for complex biochemicals on the way to bounded, replicating cells.
Billions of years ago, deep under the ocean, the pores and pockets in minerals that surrounded warm, alkaline springs catalyzed the beginnings of life. (32)
Russell, Michael, et al. The Drive to Life on Wet and Icy Worlds. Astrobiology. 14/4, 2014. A 14 member team from Cal Tech, JPL, Precambrian Ecosystem Laboratory, Japan, University of Illinois, CNRS France and more, including Elbert Branscomb and Wolfgang Nitschke, claims that the vectorial formation of living, evolving systems is impelled from their onset by far-from-equilibrium energy gradients. The paper summarizes years of research and results, with over 400 references, albeit with machine metaphors, in support of this thermal theory. The article is the latest of a series in international journals, especially Biochimica et Biophysica Acta (BBA) - Bioenergetics, from this broad European and American collaboration. A special issue of BBA above, The Evolutionary Aspects of Bioenergetic Systems (1827/2, 2013), introduced by Nitschke, contends this source precedes and subsumes an optional RNA or metabolism emphasis by their common thermodynamic drives. Later in the same journal, Free Energy Conversion in the LUCA: Quo Vadis? (Online December 2013), presses this “origin of energy metabolism” approach. Another summary is The Inevitable Journey to Being in Philosophical Transactions of the Royal Society B (368/1622, 2013) by MR, WN, and EB, Abstract below.
This paper presents a reformulation of the submarine alkaline hydrothermal theory for the emergence of life in response to recent experimental findings. The theory views life, like other self-organizing systems in the Universe, as an inevitable outcome of particular disequilibria. In this case, the disequilibria were two: (1) in redox potential, between hydrogen plus methane with the circuit-completing electron acceptors such as nitrite, nitrate, ferric iron, and carbon dioxide, and (2) in pH gradient between an acidulous external ocean and an alkaline hydrothermal fluid. Both CO2and CH4 were equally the ultimate sources of organic carbon, and the metal sulfides and oxyhydroxides acted as protoenzymatic catalysts. The realization, now 50 years old, that membrane-spanning gradients, rather than organic intermediates, play a vital role in life’s operations calls into question the idea of ‘‘prebiotic chemistry.’’ It informs our own suggestion that experimentation should look to the kind of nanoengines that must have been the precursors to molecular motors—such as pyrophosphate synthetase and the like driven by these gradients—that make life work. (Article Abstract)
Scharf, Caleb, et al. A Strategy for Origins of Life Research. International Journal of Astrobiology. 15/12, 2015. With multiple contributors (30 men and 3 women), this is a summary review of an August 2015 Earth-Life Science Institute workshop at the Tokyo Institute of Technology. The main aspects such as definitions of life, how to assimilate meteorites, thermal vents, biochemicals, scales of aliveness, and so on, are dutifully covered. It is noted that the presence of spontaneous non-equilibrium self-organizing dynamics should also be considered. But it seems to me that a deep contradiction besets any such project that needs airing. While Scharf, a Columbia University astrobiologist and author (search), leads the well intentioned group, the endeavor goes forth in a moribund cosmos already dismissed as devoid of any creative essence, direction, or destiny. What does it matter whether life began this way or that, if animate evolution and our brave human reconstruction is yet all for naught.
Schopf, William, ed. Life’s Origin: The Beginnings of Biological Evolution. Berkeley: University of California Press, 2002. A synoptic survey from historical backgrounds to earth’s formation, biochemical precursors, polymerization, genetic information and ancient paleontology which reaches this conclusion:
So even though detailed understanding has yet to be achieved, the main story of life’s beginnings is abundantly clear: Life is a natural outcome of the evolution of cosmic matter ( Schopf, 3)
Schrum, Jason, et al. The Origins of Cellular Life. Atkins, John, et al, eds. RNA Worlds: From Life’s Origins to Diversity in Gene Regulation. Cold Spring Harbor: CSH Laboratory Press, 2011. With coauthors Ting Zhu and Nobel laureate Jack Szostak, Howard Hughes Medical Institute, Boston, integrative biologists reach a similar surmise to Andrew Pratt (2011), Eors Szathmary (2007), Tibor Ganti (search) and others that a defining propensity of living systems is the formation of whole, semi-autonomous entities, by way of hereditary instruction. Life’s iterative evolution can then be viewed, in our retrospect, as a progression of increasingly free, complex and smart “proto-cells.” (And all this surely augurs for a “social proto-cell” such as Sustainable Ecovillage herein avers.)
With coauthors Ting Zhu and Nobel laureate Jack Szostak, Howard Hughes Medical Institute, Boston, integrative biologists reach a similar surmise to Andrew Pratt (2011), Eors Szathmary (2007), Tibor Ganti (search) and others that a defining propensity of living systems is the formation of whole, semi-autonomous entities, by way of hereditary instruction. Life’s iterative evolution can then be viewed, in our retrospect, as a progression of increasingly free, complex and smart “proto-cells.” (And all this surely augurs for a “social proto-cell” such as Sustainable Ecovillage herein avers.)
Schuster, Peter. Origins of Life. Complexity. Early View: December, 2009. Recent advances are the confirmation of an RNA “genetics first” pathway, along with a growing sense of how conducive the prebiotic chemical milieu is. And a theoretical synthesis and reconstruction may finally be in sight if the active organizational role of complex systems phenomena can be factored in.
Despite rather pessimistic views uttered by opponents of a natural origin of life an impressive collection of data is available now. They all speak for a sequence of prebiotic events and processes leading from networks of dynamically related small molecules and amphiphiles to biological macromolecules, compartments, and eventually protocells. Not a single one of the suggested avenues to life seems to be plausible but taking them all together in a concerted view could provide the solution. (3)
Schuster, Peter and Peter Stadler. Networks in Molecular Evolution. Complexity. 8/1, 2003. With a subtitle “A Common Theme at All Levels,” this paper claims that the way biochemicals evolved into organic complexity is by a hierarchy of autocatalytic systems.
Schwartzman, David and Charles Lineweaver. The Hyperthermophilic Origin of Life Revisited. Biochemical Society Transactions. 32/2, 2004. Since microorganisms are now found exist at temperatures exceeding 1200 C, the case for a hot biogenesis and widespread prevalence of life grows stronger.
Seckbach, Joseph, ed. Origins: Genesis, Evolution and Diversity of Life. Dordrecht: Kluwer Academic, 2004. Not yet seen, here is an excerpt from the publisher’s website. This new volume of "Origins: Genesis, Evolution and Biodiversity of Microbial Life in the Universe" is the sixth unit of the book series "Cellular Origins, Life in Extreme Habitats and Astrobiology" edited by Joseph Seckbach. Forty eminent scientists review their studies in the fields of Life from the beginning to the "Fact of Life." The history of Origin of Life and Astrobiology is well covered by these authors. Reviews cover the standard and alternative scenarios of the genesis of Life, while the chapters of "The First Cells" leading to the biodiversity and extremophiles of microbial Life.
Seoane, Luis and Ricard Sole. Information Theory, Predictability and the Emerge of Complex Life. Royal Society Open Science. February, 2018. MIT Center for Brains, Minds + Machines (Google) and ICREA-Complex Systems Lab, Universitat Pompeu Fabra, Barcelona polymaths propose a broader synthesis to help quantify and explain how genomic life came to evolve and arise by way of dynamic ecological interactivities.
Despite the obvious advantage of simple life forms capable of fast replication, different levels of cognitive complexity have been achieved by living systems in terms of their potential to cope with environmental uncertainty. Against the inevitable cost associated with detecting environmental cues and responding to them in adaptive ways, we conjecture that the potential for predicting the environment can overcome the expenses associated with maintaining costly, complex structures. We present a minimal formal model grounded in information theory and selection, in which successive generations of agents are mapped into transmitters and receivers of a coded message. Our agents are guessing machines and their capacity to deal with environments of different complexity defines the conditions to sustain more complex agents. (Abstract)
Shapiro, Robert. A Simpler Origin for Life. Scientific American. June, 2007. The veteran NYU researcher moves beyond the Replicator First persuasion, via the sudden appearance of a large self-copying molecule, in favor of life’s metabolic dynamics as initially expressed by energy-driven networks of small molecules. By so doing, still another recognition that interrelations between objects are equally relevant is achieved. The journal article is paired with an interactive, longer online version. At this SA blog, reviewers can ask questions, some of which have been answered in print. A good example of how real science works as widely collaborative and in constant review.
Shapiro, Robert. Small Molecule Interactions were Central to the Origin of Life. Quarterly Review of Biology. 81/2, 2006. The New York University researcher highlights this feature towards the convergent understanding of how cellular organisms came to be.
I have provided only a framework, and not a specific recipe, to illustrate how a coupled free-energy source could initiate the process of self-organization in a complex mixture of organic monomers. (122)