In today’s blog we visit with Dr. Michael Russell, geochemistry PhD from the University of Durham, former Principal Scientist at the Jet Propulsion Laboratory in Pasadena, California, and the man who showed how life in the Universe emerges.
David: Is life elsewhere in the universe likely?
Michael: Yes, life will onset wherever the conditions and the disequilibria (free energies) are available (see figure below: pH gradient >2 {acidulous to alkaline}, redox gradient ~800 millivolts to get started). Life needs millions of electrons per second, and it has to breathe, i.e. at its start it needed high potential electron acceptors, maybe nitrate or nitrite.
Schoepp-Cothenet, B., van Lis, R., Atteia, A., Baymann, F., Capowiez, L., Ducluzeau, A-L., Duval, S., ten Brink, F., Russell, M.J. & Nitschke, W. 2013 On the universal core of bioenergetics. Biochim. Biophys. Acta, Bioenergetics, 1827, 79-93.
Russell, M.J. & Ponce, A. (2020). Six ‘must-have’ minerals for life’s emergence: olivine, pyrrhotite, bridgmanite, serpentine, fougerite and mackinawite. Life, 10 (11), 291.
David: Can you describe the origin of life on Earth and whether that applies generally to the Universe?
Michael: This may sound semantic but to me it is a mistake to talk of the origin of life. The question should either use the term “EMERGENCE” or “ONSET”. “Origin” tempts us to think it is all for us humans, and allows all kinds of “ anything goes” ‘magical’ hypotheses to be lazily thought of; both religious and secular. Better to think Prigogine/Schrödinger here.
Russell, M.J., Nitschke, W. & Branscomb, E. 2013, The inevitable journey to being. Phil. Trans. R. Soc. Lond. B. Biol. Sci., 368, 20120254. http://dx.doi.org/10.1098/rstb.2012.0254
Branscomb, E., Biancalani, T., Goldenfeld, N., Russell M.J. (2017) Escapement mechanisms and the conversion of disequilibria: The engines of creation. Physics Reports 677:1-60 http://dx.doi.org/10.1016/j.physrep.2017.02.001.
David: In your answer to the first question, you described specific physical conditions that allow chemistry to take advantage of disequilibria and lead to the onset of life. We know that a few other places in the solar system might provide those conditions, do we not?
Michael: Not really. There is a tendency/temptation working in astrobiology to go along with the current optimism. I think! Life is just one more entropy generator, but one with very limited disequilibria to play with. More prosaically life’s “job”/work is to hydrogenate carbon dioxide, a process that produces a small but ever continuous supply of organic molecules. Thus, oxidized atmospheres are required to make a planet's ~ 1 volt battery, presuming a relatively reduced (but not too reduced) mantle (see Russell Ponce paper). Venus is the only other planet that has such an atmosphere, but no surviving water. The rest of our planets (I include the geologically active moons) generally have no atmospheres, or one’s comprising reduced carbon fluids. Thus there is no drive to life on these bodies. So though life is inevitably present throughout the Universe it is also likely to be rare.
David: Does your work help us complete the Drake equation?
Michael: It has nothing to say to the Drake equation. Forgive my prejudiced reply re the Drake equation. I tend to react in this ignorant way because many are so intent on finding life elsewhere they overlook what life “does” or can do for the Universe as it makes its inexorable way toward equilibrium (Russell et al 2013).
Russell, M.J. & Ponce, A. (2020). Six ‘must-have’minerals for life’s emergence: olivine, pyrrhotite, bridgmanite, serpentine, fougerite and mackinawite. Life, 10(11), 291.
David: Is it fair to describe your main contribution as the bringing together of multiple separate ideas into a coherent whole?
Michael: I hope not! The submarine alkaline vent theory (AVT) for the emergence of life was first put in Russell et al 1989 and I like to think it was there from the get-go, including an effective prediction of the Lost City alkaline springs in the North Atlantic in 2000 and the significance of serpentinization, though you might not have gleaned that from the forgetful literature.
Russell, M.J., Hall, A.J., & Turner, D. 1989. In vitro growth of iron sulphide chimneys: possible culture chambers for origin-of-life experiments. Terra Nova, 1, p.238-241.
Russell, M.J. & Hall, A.J. 1997, The emergence of life from iron monosulphide bubbles at a submarine hydrothermal redox and pH front. J. Geol. Soc. Lond., 154, 377-402.
David: How can you test your theory in the laboratory?
Michael: There are already many publications testing the AVT and others have been put as predictions. But space and time of our planet and its solar system revealing in the geology of our planet was my main laboratory early on. See e.g.
Russell, M. J., & Hall, A. J. (2006). The onset and early evolution of life. Memoirs Geological Society of America 198, 1.
Hudson, R., de Graaf, R., Rodin, M.S., Ohno, A., Lane, N., McGlynn, S.E., Yamada, Y.M., Nakamura, R., Barge, L.M., Braun, D. and Sojo, V., 2020. CO2 reduction driven by a pH gradient. Proceedings of the National Academy of Sciences, 117(37), pp.22873-22879.
Barge, L. M., Flores, E., Baum, M. M., VanderVelde, D. G., and Russell, M.J. (2019). Redox and pH gradients drive amino acid synthesis in iron oxyhydroxide mineral systems. Proc. Natl Acad. Sci. 116:4828-4833.
White, L.M., Shibuya, T., Vance, S.D., Christensen, L.E., Bhartia, R., Kidd, R., Hoffmann, A., Stucky, G.D., Kanik, I., Russell, M.J. (2020) Simulating serpentinization as it could apply to the emergence of life using the JPL Hydrothermal Reactor. Astrobiology 20(3), 307-326.
Russell, M.J. (2019). Prospecting for life. Interface focus, 9(6), 20190050.
David: Were you surprised by how people reacted to your ideas?
Michael: Yes and no. My previous work on the genesis of the giant lead zinc orebodies of the world taught me stoicism. One example is our discovery of the first fossil hydrothermal vents (e.g. Boyce et al. 1983) which was met by stony disbelief indicated by a visiting party of critical geologists’ reaction to my offer of being shown the discovery site in Ireland. "It’ll only take ten minutes”. "Thanks anyway but we don’t have the time”. The mine geologists had seen these fossil chimneys and facetiously called them "fossilized monkey’s thigh bones”! Yet this was our discovery that led me on to the AVT.
Russell, M.J. & Skauli, H. 1991. A history of theoretical developments in carbonate-hosted base metal deposits and a new tri-level enthalpy classification. Economic Geology: Monograph. 8, 96-116.
Boyce, A.J., Coleman, M.L. & Russell, M.J. 1983. Formation of fossil hydrothermal chimneys and mounds from Silvermines, Ireland. Nature, 306, 545-550.
Larter, R.C.L., Boyce, A.J. & Russell, M.J. 1981. Hydrothermal pyrite chimneys from the Ballynoe Baryte deposit, Silvermines, County Tipperary, Ireland. Mineralium Deposita, 16, 309-318.
David: Would you describe the feedback as ‘reasonable’?
Michael: Between 1990 and 2002 (see google scholar histogram) there was no feedback. Then there was, but then the extremely well-funded RNA world people — populating the top universities where you are not allowed to be wrong — got wind of it and have since done everything they can in the “trend setting journals” to bury it: e.g., Sutherland in Nature Chemistry opining “A requirement for ultraviolet irradiation to generate hydrated electrons would rule out deep sea environments. This, along with strong bioenergetic and structural arguments, suggests that the “idea that life originated at vents should, like the vents themselves, remain ‘In the deep bosom of the ocean buried’”. Then followed Marshall’s ludicrously opinionated and ignorant article in Nature itself, siding with the crowd (Marshall, M. How the first life on Earth survived its biggest threat—water. Nature 2020, 588, 210–213). I fought back with
“The “Water Problem”(sic), the Illusory Pond and Life’s Submarine Emergence - A Review” Life 2021, 11(5), 429; https://doi.org/10.3390/life11050429
but see also for the "physics"
Branscomb, E., Russell M.J. (2018) Frankenstein or a submarine alkaline vent: Who is responsible for abiogenesis? Part 1: What is life - that it might create itself? BioEssays 40(7) 1700179 https://doi.org/10.1002/bies.201700179
and for its emergence
Branscomb, E., Russell M.J. (2018) Frankenstein or a submarine alkaline vent: Who is responsible for abiogenesis? Part 2: As life is now, so it must have been in the beginning. BioEssays 40(8) 1700182 https://doi.org/10.1002/bies.201700182
This opposition from the "great and the good” matters as it deprives young researchers of academic jobs and also stymies much of the needed research and experimentation. To me, Jim Watson’s attitude grows more understandable with age!
David: How did you end up in Milan and how is your Italian? I’m actually from Naples, which is a different world…
Michael: After leaving JPL in 2019 we decided to live close by one of our daughters (variously living in Australia, England, 2 in Scotland and Italy) and take advantage of the one that lived in Italy along with our twin Italian grandchildren living there too. Part of the choice, apart from better weather, was our view that the only place to go, having lived in the latest (and last?) of all the “Florences”, i.e. Los Angeles, was back to the source of recent western “humanitarian civilization”, Italy! And we love it here. In spite of the expectations of our globe-trotting friends we do not live in a villa by a Lake or overlooking the Middle Sea, but 17 kilometers NW of Milan in a 400 year old “cortile” with a spectrum of Italian neighbors and we love it - even the small scale relatively kindly local politics! I have made several delightful, excellent and modest academic and intellectual friends/collaborators here. My Italian is lousy I am afraid - my friends and family (son in law Salvatori Calderazzo from Puglia) like to speak English, so along with Covid we have had little practice. And at 82 life is getting short and there is so much research still to do!
PS. If you ever go (again?) to Los Angeles you must visit Simon Rodia's Watts Towers (if you haven’t already).
David: Thank you Dr. Russell! PS. I never thought of Milan as being associated with good weather (try Positano instead) and I suspect your son in law’s first name is Salvatore...
Michael: Indeed!
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