Chemical Evolution: Your science textbook is wrong on the origin of life: Miller-Urey Experiments

Some really smart people, from Charles Darwin to scientists today, believe in abiogenesis. A “primordial soup” of chemicals led to life as we know it. But is this really the case?

1. Charles Darwin To J. D. Hooker, 1 February [1871] https://www.darwinproject.ac.uk/lette...
2-5. Biological Science, Freeman, 5th ed. pg. 44, 4, 33,59
6. "The consensus is that life did arise naturally from the nonliving … the conclusion has, indeed, really become inescapable, for the first steps in that process have already been repeated in several laboratories".
– George Gaylord Simpson, Commenting on the results from the Miller-Urey experiment in the prestigious journal "Science", The World Into Which Darwin Led Us. Science 1960. 131: 966-974.
7. “There was some optimism that, had the experiment been left running, living creatures would soon be crawling out of the laboratory.”
–Walker SI, Packard N, Cody GD. 2017 Re-conceptualizing the origins of life. Phil. Trans. R. Soc. A 375: 20160337. http://dx.doi.org/10.1098/rsta.2016.0337
8. *Toxic in the chemical sense; that is, it reduces or prevents desired chemical reactions. Many necessary ingredients for abiogenesis are also toxic to existing life. For example: hydrogen cyanide (once used as a chemical warfare agent) and formaldehyde (the active ingredient in embalming fluid). That, while interesting, is not the criticism here.
9. A. Wotos el al., "Synthetic connectivity, emergence, and self-regeneration in the network of prebiotic chemistry," Science (2020). https://science.sciencemag.org/conten...
10. Generation Round 7 of Synthesis Date: 82 Biotic Molecules generated / 36,685 Cumulative Sum of All Molecules = 99.777% Ratio of Abiotic to Biotic Molecules. This problem would be compounded greatly with more time and successive rounds of generation.
11. *technical note: Unwanted cross reactions would leave these amino acids unable to properly interact to fold into functional proteins. Sort of like a lock packed with concrete or gum. Not to mention the various problems of dilution, chirality, and stability if polymers could form.
12. The Murchison meteorite contained “tens of thousands of different molecular compositions, and likely millions of diverse structures,” which “suggests that the extraterrestrial chemodiversity is high compared to terrestrial relevant biological- and biogeochemical-driven chemical space”

Translation: For each molecule you did want there are innumerable things we don’t want and would get in the way.

[Schmitt-Kopplin, P., et al., High molecular diversity of extraterrestrial organic matter in Murchison meteorite revealed forty years after its fall. Proc Natl Acad Sci U S A, 2010. 107(7): 2763–2768.]
13. Ruiz-Bermejo, M., Menor-Salvan, C., Osuna-Esteban, S., Veintemillas-Verdaguer, S., 2007. Prebiotic microreactors: a synthesis of purines and dihydroxy compounds in aqueous aerosol. Origins of Life and Evolution of the Biosphere 37, 123e142.
14. “[Miller & Urey] showed that organic molecules (in this case amino acids) could be created from inorganic materials by natural environmental conditions” https://www.americanscientist.org/art...
15. "Geochemical Sources and Availability of Amidophosphates on the Early Earth"
Gibard C, Gorrell IB, Jiménez EI, Kee TP, Pasek MA, Krishnamurthy R. Geochemical Sources and Availability of Amidophosphates on the Early Earth. Angew Chem Int Ed Engl. 2019 Jun 11;58(24):8151-8155. doi: 10.1002/anie.201903808.
16. “Ribose is the sugar that is the building block to produce RNA. Ribose rapidly decomposes in aqueous solution. The half-life of ribose is 73 min at 100 oC and pH 7.0, and 44 years at 0 oC and pH 7.0.” The authors also point out that the degradation rate of ribose in a prebiotic ocean could have been even faster, considering that the pH of the ocean today is 8.2 (more than 10x more alkaline) than neutral pH, which would increase the ribose destruction rate by ~50%.
Larralde, R., Robertson, M.P., Miller, S.L.*, 1995. Rates of decomposition of ribose and other sugars: implications for chemical evolution. Proceedings of the National Academy of Sciences of the United States of America 92, 8158e8160.
17. Levy, M., Miller, S.L., 1998. The stability of the RNA bases: implications for the origin of life. Proceedings of the National Academy of Sciences of the United States of America 95, 7933e7938.
18. Chart adapted from © 2003 International Union of Biochemistry and Molecular Biology 22nd Edition Designed by Donald E. Nicholson, D.Sc., The University of Leeds, England – and Sigma-Aldrich. Used with permission.
19. For more information: The Stairway to Life https://www.amazon.com/Stairway-Life-...
The mystery of Life’s Origin https://www.amazon.com/Mystery-Lifes-...

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