16 May 2018

Review of Karo Michaelian's Thermodynamic Dissipation Theory, PART 2. Darwin and Natural Selection

Karo Michaelian
'Thermodynamic Dissipation Theory
of the Origin and Evolution of Life',
12th printing, March 2017
In my first blog about Karo Michaelian's Thermodynamic Dissipation Theory I discussed his claims about the effects UV light on life and the inefficiency of photosynthesis. In this blog I discuss his views on the Darwinian theory of evolution.

Will to survive

Two striking criticisms are: the "will to survive" and the "tautological definition of fitness".
The "will to survive" occurs at least 17 times in his book. It must be crucial for his argumentation. Here a few examples:
  • "Traditional evolutionary theory based on an implicit metaphysical "will to survive" of the individual and the tautology of "survival of the survivors"  has little explicative value." (p. xxvi)
  • "... do not have a mysterious "will to survive and proliferate" as the Darwinists are obliged to see it." (p.129)
  • "The implicit and unjustified assumption of the "will to survive" in the Darwinian theory can now be replaced with an explicit and physically founded "will to produce entropy" (colloquially speaking)". (p.139).
Michaelian never gives a reference for the "will to survive". Charles Darwin did not use the "will to survive" in any of his books, articles and published manuscripts. This can be easily checked:
  1. Go to Darwin Online website 
  2. Go to Advanced Search
  3. type in the field Full Text: "will to survive" (or: "drive to survive", "survival instinct")
  4. Identifier: empty *)
  5. Results: No hits
*) If desired a search can be narrowed to The Origin of Species [1st ed.] by typing F373 in the field Identifier, etc. No identifier means all his published works. See for identifiers this page.

So, the conclusion is straightforward: Michaelian accusation of a mysterious, metaphysical will to survive is not based on Darwin and therefore does not need to be replaced by anything. Furthermore, the 'will to survive' is not present in any Evolution textbook [4]. See for an overview of 36 evolution textbooks my website. Any textbook of the last 35 years is good enough for this purpose.

Ironically, his theory is explicitly teleological and metaphysical. In 19.3 he rejects the standard view in science that 'Life has no Purpose' (p.291). According to Michaelian life has a purpose. But the "will to produce entropy" is just as metaphysical as the "will to survive". Really surprising for a scientist practicing the most exact of all sciences: physics.

Survival of the survivors tautology

The "survival of the survivors tautology" occurs at least 9 times in his book! It must be an important part of his argument.
Freeman & Herron
Michaelian notes that philosopher Karl Popper pointed out that "survival of the survivors" is a tautology and later Popper changed his views on Darwinism somewhat (see footnote on page 266 of Michaelian's book). Sadly, all of this is outdated and irrelevant because in Evolutionary biology fitness and natural selection are defined and used in a non-tautological way. Again pick up any of the evolution textbooks of the last 35 years. The tautology is refuted in one of the oldest Evolution textbooks I have on the shelves: Minkoff (1983) Evolutionary Biology. Minkoff defines natural selection as the "differential contribution of heritable variations to the next generation" (page 82). This blog post is not the place to explain the theory of natural selection. An excellent discussion of the testability of natural selection can be found for example in Freeman and Herron (2007) Evolutionary Analysis [1].

Sadly, the tautology problem is a well-known creationist objection to evolution. In the classification of Mark Isaak (2007) The Counter-Creationism Handbook it is listed as Claim CA500 (page 32) or see the TalkOrgins website. The father of the Intelligent Design movement Phillip Johnson didn't  miss the opportunity to use the tautology to make a fool of Darwinists (my review).

Remarkably and inconsistently, elsewhere in his book Michaelian knows very well the non-tautological definition of fitness and natural selection (chapter 19 section 8 'Evolution through Natural Selection', page 299) and even mentions antibiotic resistance as an convincing example of natural selection. But that's the only example he thinks exists. He needs one consistent view throughout the book, getting rid of views that contradict each other. If he wants to criticize a theory, the first thing is to know the subject in the same depth as the experts [2]. It seems that Michaelian wants to discredit natural selection as much as possible in order to clear the way for his own thermodynamic selection.

Sadly, his criticism of natural selection and fitness are targeted at wrong and outdated views of evolution. Natural selection is in biology what the Second law of thermodynamics is in physics. Natural selection does not and cannot contradict thermodynamics or any other physical law. That would be a miracle. Natural selection assumes every possible physical, cosmological, chemical and geological condition. It is in this extended environment that natural selection operates and has operated since the origin of life.

There are however conditions where natural selection overrules thermodynamic selection in the sense that a flying bird overrules gravity. In general: when an organism is excellent in thermodynamic dissipation (entropy production) and survives to old age in good health, but has zero offspring, its excellent characteristics will not be inherited. And that's the end. That's where natural selection overrules thermodynamic selection.
If an organism with low dissipation (entropy production) produces more offspring than an organism with high dissipation, and this dissipation property is at least partly genetic, then the frequency of this property in the population will increase. Non-random representation of genetic differences in future generations is called natural selection. Natural selection (and a view other principles in population genetics such as drift) is sufficient to explain the properties of organisms given their environment.

gliding storks gain height for free (source)
see stunning beautiful video (16 secs)

There is a deep problem with thermodynamic selection. If thermodynamic dissipation means using and wasting as much energy as possible, then thermodynamic selection is refuted. In the animal world there is a rule of thumb: if you waste energy you are a loser [3]. A good demonstration of the principle is the seasonal migration of birds. Like sailplanes, hang gliders, para-gliders, European storks use rising air (thermals or ridge lift) to gain height (see picture). The storks subsequently glide for free downwards and forwards to travel a great distance and locate another column of rising air to gain height again. Of course they could simply use muscle power to travel in a straight line to their destination, but that would be very costly energetically. That would be stupid. Energy is not for free. Birds  do not fly "to benefit entropy production". They would not make the thousands of kilometers of their seasonal migration. The migration of birds has been compared to the Olympic Games because of the high physical demands of a non-stop flight for thousands kilometers. Especially in birds but also in planes, the need to be as lightweight as possible is easy to understand. One could store as much fuel as possible, but that increases weight and that is a disadvantage. The point is to store just enough energy and use it efficiently. That is: don't waste energy. The anatomy, physiology and behavior of birds is organized around this principle. And that refutes the idea that dissipation (entropy production) is maximized.

The problems with KM's view are connected to the question what life is. In contrast to free-floating molecules (pigments) in solution, cells and organisms are almost by definition not directly governed by physical forces. Bacteria, plants and animals do not spontaneously arise from abiotic materials under the influence of physical forces. Proto-life could. The big difference is that life contains inherited structures that harness energy from the environment. Metabolism is under genetic control. These structures make life to a large extent autonomous. Life is not at the mercy of thermodynamics. Molecules are. Bénard cells, Belousov–Zhabotinsky reaction, etc. are spontaneous, dynamic, temporary structures exclusively governed by physical forces. Life enjoys a structural permanence not present in dead non-equilibrium thermodynamic systems. It doesn't make sense to say that organisms are controlled by a 'local thermodynamic flow'. Energy (food) has to be actively searched, captured and digested. So, one cannot extrapolate from the fundamental molecules of life ('UV pigments') which obey the laws of physics and chemistry, to cells and organisms. Organisms circumvent the laws of physics in ingenious ways. Drop a dead bird, and it falls to the ground in agreement with the law of gravity. Drop a living bird and it flies away. That's life.

I think the value of Karo Michaelian's theory is in the application to single molecules especially at the origin of life, and the origin and replication of DNA. But there is more. KM has more ideas than a whole team of experts can evaluate. He has a list of no less than 16 paradigms in need of reform (chapter 19). Among them The RNA world hypothesis, Metabolism or Replication first, The Last Universal Common Ancestor, The Great Oxygenation Event, the Hydrothermal Vent Origin of Life, Pigments provide photo-protection, Photosynthesis is optimized in nature, and Panspermia. Additionally: homochirality (chapter 14). So, it is clear that he is far more than 'just another critic of evolution'. I personally like original writers the most. Right or wrong. It is intellectual entertainment. And yes, while reading, thinking, and writing, the brain produces a lot of entropy.


Notes

  1. Freeman and Herron (2007) Evolutionary Analysis, fourth edition. Chapter 3.2 'Evolution by natural Selection' (p.76-93). They list 4 postulates of natural selection and how each of them is tested. On page 93 under the heading 'Fitness is Not Circular' the tautology problem is discussed explicitly.  Required reading! See homepage of my WDW website and the Introduction page for an overview of Evolution textbooks.
  2. In chapter 19 two sections deal with natural selection: 19.2 and 19.8. These should be severely updated and united in one section. Or deleted altogether. Please note that there is no 'natural selection' in the Glossary of technical terms! So, it is undefined in his book!
  3. "if you waste energy you are a loser" are my words, but something very similar is stated by John Tyler Bonner (2006) Why Size Matters, (p.123-): "There is also a constant selection, no matter what the size, for greater [physiological] efficiency." KM: you should seek a connection with metabolism theory. There has been a lot of research on metabolism rates in the animal world. Interesting theory: Rate of living theory: "Support for this theory has been bolstered by studies linking a lower basal metabolic rate (evident with a lowered heartbeat) to increased life expectancy." So, rate of metabolism is under genetic and evolutionary control, and is not simply dictated by physical laws.
  4. Coincidentally, the first sentence in an article about ribosomes in Science 18 May 2018 reads: "From an evolutionary perspective, life involves two simple goals: survival and reproduction." There is, however, a subtle difference between goal and purpose: goals can be measured whereas purposes cannot be measured. (source) [added 18 May 2018]

15 May 2018

Guest blog Karo Michaelian PART 2: Is photosynthesis inefficient?

[ PART 1 ]

Ok, so why would life develop oxygenic photosynthesis which essentially removed this beautiful source of free energy that was available almost everywhere? This question is loaded because you are still in the Darwinian perspective. Let’s go back to the thermodynamic perspective. As I mentioned above, life has no inherent self interest in existing or proliferating or evolving. What is fundamentally important is photon dissipation. If a series of complexifications of DNA with other fundamental molecules and the UVC light produced pigments in the visible and this permitted dissipation with the longer wavelengths (also dissipative structuring and proliferation, but now in the visible), then that would be great because now photon dissipation is extended to other more intense wavelengths which were always available in the visible. And, if one of these new pigments happened to be the oxygen molecule O2, then better still since oxygen in the atmosphere can dissipate UVC light. Ozone is produced through the UVC dissipative structuring of oxygen. So now the UVC light is dissipated in the upper atmosphere and life dissipates visible light at the surface. Now we start to get improved fidelity of replication on Earth’s surface and protection of delicate amino acid bonding in complex enzymes thanks to oxygen and ozone, and so now life can develop even more complex enzymes and biosynthetic pathways to produce even more pigments which cover ever more of the solar spectrum and produce ever more entropy.

The present biosphere is one great dissipating system with abiotic processes coupled to biotic processes. The only, and therefore fundamental, reason for the biosphere’s existence is to dissipate the solar photon potential (to produce entropy at ever increasing rates).

Photosynthesis at the beginning of life (the dissipative structuring of the fundamental molecules and their proliferation) was obviously connected to photon dissipation (UVC dissipation) as explained above. Photosynthesis today is obviously connected to photon dissipation today (but now in the visible through more complex biosynthetic pathways). The structuring of material, anywhere, at anytime, is obviously connected to the dissipation of a generalized thermodynamic potential, be this the photon potential, a chemical potential, a heat gradient, a concentration gradient, etc. Structuring, e.g. photosynthesis, cannot be separated from dissipation (entropy production). However, my point is that it is not correct to ignore the imposed generalized thermodynamic potential and consider only the structure alone and assign to it an inherent will to survive, to propagate, and to evolve (the Darwinian perspective). From the thermodynamic perspective, it does not make sense to say that biomass production (or reproductive success) is optimized, but rather that the dissipation of the external generalized thermodynamic potential is optimized. If this requires more biomass, then so be it, but this is not always the case, sometimes a simple coupling of different existing biomass is called for (e.g. tryptophan+DNA or the biosphere), or the invention of a new pigment which allows dissipation in a new wavelength region. The Darwinian perspective leads to many inconsistencies and paradoxes. The thermodynamic perspective considering the structure (or process) together with the imposed generalized thermodynamic potential and its dissipation (obtained by that structuring), is the fundamental perspective we should take to avoid problems and paradoxes.

In the thermodynamic perspective, it is not the individual that is being “selected” but rather the global dissipating unit known as the biosphere that is being selected based on its global entropy production in its solar environment. If one individual (or species) replacing another leads to greater global entropy production, then this state is more stable than the previous and will therefore be more probable over long times, but it is not by any means inevitable that the system will instantly move towards that state, much depends on the perturbation and on critical points of bifurcation in this tremendously complex non-linear system. This is not an equilibrium thermodynamic selection in the canonical ensemble in which the most stable (lowest free energy) configuration is most probable, but rather it is a non-equilibrium thermodynamic selection in which the largest entropy producing stationary state is the most probable. In analogy to equilibrium thermodynamics where the lowest free energy state is the most probable, but not inevitable, in non-equilibrium thermodynamics, the greatest entropy producing state is the most probable but not inevitable. For the biosphere, an enormous number of entropy producing stationary states exist, each with its particular value of global entropy production. External or internal perturbations (microscopic and macroscopic) allow the system to continuously explore these states with permanence being related to the states accessibility and non-equilibrium stability or entropy production.

I admit that this may be a bit confusing, even those working on the front-line of non-equilibrium thermodynamics are struggling with the details, but I can get more into it after you post your second blog as I gather it will address non-equilibrium thermodynamic selection in the biosphere.

My students and I have in fact carried out experiments (Michaelian and Santillán, 2014) and one of them is described in chapter 12 of my book. It was designed to test the hypothesis of ultraviolet and temperature assisted reproduction (UVTAR) of DNA. In this experiment we showed that UVC light can indeed denature short (25 bp) segments of DNA. The mechanism by which it does this we now think is related to photon-induced charge transfer among two bases forming a Watson-Crick pair, but this is still under investigation (Reyna and Michaelian, 2018). The other part of the reproduction process, enzyme-less extension has been demonstrated by others; even though it is rather slow it can be speeded up considerably with the simple addition of tryptophan (Horowitz et al., 2010). So putting it all together in a single experiment should not represent a great challenge, however, our progress is slow mainly because we spend most of our time answering curious but difficult referees.

We have, so far, not been able to publish the experiment carried out in 2012 in journals related to the origin of life. The referees tend to belong to mafias which either defend the deep sea hydrothermal vent origin of life theories or the RNA World origin of life theories. They generally consider new theories as being hostile to their own. Our papers are published in European biogeoscience or thermodynamic journals, these tend to be much more open minded than the American origin of life journals. I would ask your readers to consider not confiding substantially more in a scientific work simply because it was published in a particular journal, all it means is that two, or at most three people, did not find your theory overly hostile to their own. I believe that our actual publishing scheme needs an urgent overhaul. I would like to see something like what ResearchGate is proposing, which is along the lines of your blog; researchers publish their papers in an open forum, and allow and respond to criticism openly. The value of beginning to read an article can be approximately ascertained from the number and weight of the recommendations it receives. Unfortunately, our universities and institutes have a dreadful bureaucratic tradition. They would rather go on spending millions of dollars or Euros on subscriptions to journals, or for open access publishing in these journals, in order to obtain a seal of “credibility” from an established editorial house rather than allow universal, free, and rapid access to all new ideas. I think a lot of this has to do with the mafias I referred to above who don’t take kindly to open criticism and want to conserve the credibility of their publishing niche even though the science has moved beyond them.

The history of the association of dissipation with the structuring (or processes) of life go back to only 27 years after the publication of On the Origin of Species when Boltzmann (1886) wrote that “the struggle for existence was not a struggle for raw material, neither for energy, but rather for entropy [production]”. Many scientists have taken up and developed Boltzmann’s insight, from Onsager(1931), Schrodinger (1945), Prigogine(1972), Nicolis (1977), Zotin (1984), Ulanowicz (1987), Morel and Fleck (1989), Swenson (1989), Schneider and Kay (1994), Michaelian(2005), and others I am forgetting (but are cited in my book), and have applied CIT formalism to questions regarding life and present ecosystems. I have cited these authors in my book in both a historical context and in recognition for their contributions to my theory.

You mention Jeremy England and I have read his papers, but I do not find anything in them regarding the origin of life. What he seems to be doing in a rather tortured and not so honest way, by using equilibrium statistical mechanics and failing to cite original work, is to proclaim “discovery” of a relation between material structuring and entropy production. However, as I mentioned above, this relation was already worked out many years earlier, starting with Boltzmann (1886) and formally with the founding of CIT theory by Onsager (1931) and Prigogine (1972), and many others have already applied this relation to these aspects of life (see citations above). However, England will not get very far using an equilibrium formalism to treat a system which is certainly out-of -equilibrium. The quote you mention by England comes from a Quanta magazine article in which the author presents England’s (2013) paper on the statistics of replication as a “new physics theory of life”. Frankly, it appears to me to be just poor or sensationalist journalism because the Quanta article has nothing to do with England’s paper and no “new theory” has ever been presented by England. At this risk of sounding pretentious, the article and England’s quote appear to be imitations of my first paper published some 5 years earlier on the subject (Michaelian 2009; 2011), but I leave that up to you and your readers to judge.

I hope I have answered the most basic points of your criticism on your blog, but if not, please don’t hesitate to engage me.

Finally, I hope you will afford me some self- and group-indulgence and allow me to make some publicity as a tribute to the hard work of my collaborator Alex Simeonov, my dedicated students (see the Preface of my book), and myself on the thermodynamics of the origin of life. I think that it is fair for me to claim that our particular contribution has been to emphasize the importance of dissipation specifically to the origin of life itself and I was the first to identify a generalized thermodynamic potential that life may have been dissipating at its origins in the Archean, the UVC photon potential (Michaelian, 2009; 2011), contrary, as you say, to mainstream opinion concerning this light at that time. A student of mine has been working on the general form of this photon potential as derived from the Planck equation for the entropy of a beam of light (Cano and Michaelian, 2018). I proposed that the fundamental molecules of life were microscopic dissipative structures (Michaelian, 2009; 2011; 2016; 2018), and suggested an enzyme-less mechanism based on a dissipation-replication relation that could have bootstrapped early replication of RNA and DNA (Ultraviolet and Temperature Assisted Replication ,UVTAR) which also, by the way, provides a simple explanation for the homochirality of life (Michaelian, 2010). Together with a student, we performed an experiment which has demonstrated the viability of the UVTAR mechanism (Michaelian and Santillán, 2014) and another student has been working on a theoretical explanation of this observed UVC-induced denaturing (Reyna and Michaelian, 2018). I have shown how dissipation could have given rise to the perceived vitality of life, the proliferation of the fundamental molecules (Michaelian, 2013). Together with my collaborator from Macedonia, Aleksandar Simeonov, we have applied these ideas to the other fundamental molecules (Michaelian and Simeonov, 2015) and to the origin of the organic molecules in space (Michaelian and Simeonov, 2017). With other students, we have applied these ideas to information accumulation in DNA (Mejía and Michaelian, 2018), to the origin of fatty acids and phospholipids (Michaelian, Rodríguez and Simeonov, 2018), simple proteins (Mejía and Michaelian, 2018), and to the formation of complexes of fundamental molecules (Michaelian, 2018).

In my future response to your second blog on these themes, I will describe what we have been working on and publishing concerning the relation between Darwinian Theory and dissipative thermodynamics of the biosphere. I thank you and your readers for giving credit where credit is due because what motivates most a scientist is the recognition by his/her peers that he/she has contributed something original to the collective human knowledge. Speaking on behalf of my students, collaborators and myself, our hard work has been more than repaid by your interest and honest recognition of it in this blog. I remain at your service here to discuss any other detail of my book and to address any other doubt or criticism regarding the theory which you or your readers may have.

With my best regards,

Karo Michaelian.



References

14 May 2018

Guest blog Karo Michaelian: Is UV light harmful or beneficial for life?

Karo Michaelian
Universidad Nacional Autónomade México
Dear Gert,

I congratulate you for your very interesting blogs and I thank you sincerely for your consideration and analysis of my book, as well as for providing me this opportunity to clarify certain aspects of my theory and to contest some assertions you have made in your blog which I do not agree with, or are not part of my theory. (References cited within the text are given at the end.)
With reference to the “UV-resistant RNA and DNA” section of your blog, the exceptional absorption and de-excitation properties of the nucleic acids in the long wavelength UVC region (210-290 nm) I do not attribute to a molecular stability issue. This has been attributed as such by others, in fact, by those who performed the experiments and discovered these characteristics. They assert, as you correctly describe, that this would lead to a kind of thermodynamic selection pressure for these molecules over others which would not be so stable under UVC light. The first to make such a hypothesis was Carl Sagan (1973), and later others including Armen Mulkidjanian et al. (2003) who further developed this hypothesis and discovered many interesting details concerning the origins of photosynthesis. However, in my book I criticize this hypothesis since there is a much simpler way for nature to make fundamental molecules stable against UVC light, for example by making them either transparent to, or reflective to, it. By changing just one double covalent bond in a molecule to a single covalent bond and adding a proton (H atom nucleus) to take up the extra electron of the lost bond, one can make a modified molecule which would be transparent to this light. (The absorption spectrum of carbon based chromophores depends on the number of conjugated carbon bonds, by reducing the number of conjugated bonds by only one, the absorption spectrum shifts to considerably shorter wavelengths, and by increasing the number of conjugated bonds by one, the absorption spectrum shifts to significantly longer wavelengths.)

So, there must be another reason why the nucelobases, and, in fact, most of the fundamental molecules of life, all absorb within exactly the UVC spectral region that was arriving at Earth’s surface during the Archean. One could argue that this wavelength region would have been very useful for direct synthesis before the invention of complex biosynthetic pathways, and I argue this in my book as a plausible reason for the strong absorption here. In fact, this region of the spectrum is exactly that which is useful for making structures, because for lower energy photons (longer wavelengths) there is not enough energy in a single photon to break and remake carbon covalent bonds. At shorter wavelengths, there is too much energy and the photons can disassociate the molecule by ionizing it (destroy it).

But even this is not the whole story; there is another related but distinct reason for absorbing in the UVC. Life, as any irreversible process, could not have had any inherently conceived will to come into being, or to survive, or to evolve. It is simply a process of dissipative structuring, like a hurricane or a convection cell that arises “spontaneously” under what we call a “generalized thermodynamic potential” (e.g. temperature gradient, concentration gradient, chemical potential, photon potential, etc.). The thermodynamics of dissipative structuring of material under a generalized thermodynamic potential was worked out by Lars Onsager and Ilya Prigogine starting in the 1930’s and cumulated with the formalism known today as “Classical Irreversible Thermodynamics (CIT)”, later extended into the non-linear regime and further developed by many others. Both Onsager and Prigogine received separate Nobel prizes for their work on CIT. In simple terms, one can say that CIT describes the phenomenon of material spontaneously organizing under a generalized thermodynamic potential, on both macroscopic and microscopic scales, in such a manner so as to increase the rate of dissipation of that imposed generalized thermodynamic potential. For example, convection cells arise “spontaneously” under a sufficiently strong temperature gradient imposed over the fluid to dissipate that gradient (i.e. to help move heat from the hot to the cold surface, or, in more general thermodynamic language, to “increase entropy production”).

Now, my initial idea was; What if the fundamental molecules of life were microscopic dissipative structures? What if under a short wavelength photon potential material spontaneously organizes into structures which we recognize as the fundamental molecules of life in order to reduce that photon potential (i.e. to help convert short wavelength photons into many long wavelength photons, or to increase entropy production). I suggested some years ago (Michaelian, 2009; 2011) that this may be a plausible explanation for the origin of life and have over the years uncovered and accumulated much evidence for this. For example, please have a look at a recent paper of mine which looks specifically at the dissipative structuring of Adenine under a UVC photon potential (Michaelian, 2018). Together with my collaborator Aleksandar Simeonov from Macedonia, we have shown how this seems to be the case, in fact, for most of the fundamental molecules of life (Michaelian and Simeonov, 2015), and even for the organic molecules found in space (Michaelian and Simeonov, 2017, also summarized in my book).

If the above is true, then we have an explanation from classical irreversible thermodynamic theory for the appearance of the fundamental molecules of life and for their extraordinary absorption and dissipation characteristics in the UVC. So, these characteristics are not only about stability, but essentially about photon dissipation. In fact, it turns out to be even more interesting than this. We sense that there is some kind of “vitality” to life, for example that it tends to proliferate and spread over the whole of Earth’s surface. Where does this vitality come from? We don’t seem to see this vitality in other non-living systems. Is it unique to life? No, we just call it something different when we see it in non-living systems and we do not make the connection to living systems. For example, consider an autocatalytic chemical reaction. A chemical reaction is a non-living irreversible process that dissipates an imposed generalized thermodynamic potential known, conveniently enough, as a “chemical potential”. An autocatalytic chemical reaction is one in which one of the products of the reaction acts as a catalyst for the reaction itself. For example, the simplest
would be;

A + B -> 2B.

Prigogine has shown, using Classical Irreversible Thermodynamic (CIT) Theory, that if a product of a chemical reaction, B, acts as a catalyst for the same chemical reaction that produced it, then the concentration of that catalyst product, B, in the stationary state can increase (proliferate) to values many orders of magnitude over what would be expected if the reaction were headed towards equilibrium, which would be the case for no chemical potential imposed over the system (the chemical potential for the system above would be the continuous supply of A from the environment). Using this analogy and the same CIT formalism, I showed (Michaelian, 2013) that if a product of a photochemical reaction acts as a catalyst for the dissipation of the same photon potential that produced it, one could expect the concentration of that product to increase many orders of magnitude over what could be expected under near equilibrium conditions (i.e. without a continuous photon potential imposed over the system).
So, for example, the fact that adenine acts as a catalyst for the dissipation of the same UVC photon potential that produced it through the dissipative structuring described earlier, explains its proliferation over the whole of Earth’s surface during the Archean. Generalizing the above for dissipative structuring of more compound and complex systems, we can see how we have a thermodynamic explanation for the vitality of life. This vitality is not something inherent to the system (life) itself but to the system plus imposed environment (e.g. adenine plus the UVC photon potential). We do not require a mystical inherent “will to thrive” or new laws of nature to describe the vitality of life. So, again, it is much, much, more than a stability issue; the absorption and dissipation of UVC light in the fundamental molecules during the Archean was connected to their dissipative structuring and proliferation … the vitality of life.

Ok, what about your assertion that only someone ignorant could not understand that UVC light is dangerous to life and that I should have given reasons in my book for why I believe that UVC light was not dangerous to life rather than criticize others for holding the contrary mainstream opinion. In fact, I emphatically do give reasons for why I believe UVC light was not dangerous to incipient life in my book, but in many different places, so maybe it was not as obvious as it could have been. I will try to condense my reasons in one place here.
I am absolutely certain that UVC light is dangerous to present life. Nobody has to convince me of that. But the important word is the pronoun “present” (life). Present life is dependent on complex enzymes that are made up of amino acids connected together and folded in on each other into a very particular three dimensional structure important for its function. Some of the bonds between amino acids in a protein are very sensitive to UVC radiation. If you break even one of those bonds, the enzyme may take on another three dimensional structure and become totally useless. However, these complex enzymes obviously did not exist at the origin of life, so let’s not worry about them. “But wait”, you say, “DNA and RNA probably existed and we know that these also are very sensitive to UVC radiation”. That is certainly true, but let’s look in detail at the sensitivity and see if it really was a problem at the origin of life.
By far the most damage that UV light does to RNA and DNA are lesions called cyclobutane pyridmidine dimers (CDPs). These consist of the formation of covalent bonding between adjacent pyrimidines on the same DNA or RNA strand. Examples are thymine-thymine dimers (TT) and less common cytosine-thymine dimers (CT). The quantum efficiency for producing all of these dimers plus all other lesions together is about 1/100, i.e. one in a hundred photons in the UVC region absorbed on DNA will cause a lesion on a typical DNA. The dimers are dangerous today since they lead to a mutation on subsequent reproduction of the DNA which could then lead to skin cancer or other problems. (The other damage, apart from dimer formation, caused by UVC light on DNA, for example, strand breakage, have a much smaller quantum efficiency so let’s ignore them for the moment.)
Because of its importance to skin cancer, many people have studied cyclobutane pyrimidine dimers (CPDs). They find that the wavelength for maximum production is in the UVC between 255 and 260 nm. Therefore, these lesions are usually studied using a mercury arc lamp which emits a strong line at 254 nm. However, it has also been known that the dimers can be separated again into their normal monomer native state by absorbing another UVC photon, but at the shorter wavelength of 238 nm. Therefore, as long as you have a light source with a range of wavelengths of similar intensities between 230 and 260 nm (true for the Archean sun but not for mercury lamps) then this “damage” is not permanent damage. In fact, the cross section for this monermization is much larger than that for dimerization. One can do the calculation (I have done it) and it turns out that at the steady state (after sufficient time), under a very intense flux of UVC light containing both these wavelength components (as in the Archean solar photon spectrum), only a few percent of all the potential CPDs (adjacent TTs or CTs) on a given DNA would be in the dimer formation. Now, if you include the amino acid tryptophan with your DNA sample, it intercalates between the bases and acts as a photolyase and the probability of dimer formation goes down by another two orders of magnitude (Arcaya et al. 1971). So the probability of a possible CPD being in dimer formation would be about one in 10 thousand.
Only one in ten thousand of potential dimers actually in dimer formation today would result in mediocre fidelity, enough errors to cause havoc with the cellular reproduction occurring in any complex organism today. However, at the beginning of life, as you indicate in your blog, we cannot suppose we had complex enzymes for replication, but rather we had only the physical conditions (I suggested UV and Temperature Assisted Replication, UVTAR). In this case, since we don’t need enzymes, we don’t need perfect fidelity of replication. A little fidelity would be nice though, for example for conserving anticodons coding for tryptophan so that we reduce dimer formation, and tryptophan can act as an antenna molecule for greater dissipation (tryptophan, like DNA, absorbs strongly in the UVC), and is an amphiphilic molecule (both hydrophobic and hydrophilic ends) useful for preventing sedimentation, to keep DNA floating at the ocean surface, etc. (see Mejía and Michaelian, 2018). Interestingly, tryptophan has strong chemical affinity to its anticodon (Yarus et al., 2009).

It turns out that the aromatic amino acids which absorb UVC light (tryptophan, tyrosine, phenylalanine, histidine) are all stable against UVC light. The other amino acids are basically transparent to the long wavelength UVC region of interest and therefore these also are stable under such a UVC environment. The same goes for fatty acids and phospholipids.

I hope this convinces your readers that UVC light was not a problem to life at its origin, and in fact, was absolutely necessary for dissipative structuring through a direct photosynthesis comprising of the breaking and remaking of carbon covalent bonds and for proliferating the fundamental molecules. If you are still not convinced, then consider this; Earth’s surface was subjected to this long wavelength UVC light for at least 1000 million years until oxygenic photosynthesis became important enough to overwhelm the natural oxygen sinks at about 2.7 Ga. Does it make sense (allowing yourself to go back into the approximate Darwinian perspective) that life would have shunned this beautiful source of free energy and spent so much time hiding from it? I think you will admit that this does not make sense.

[ Part 2 ]

References

01 May 2018

The Origin of Species by Means of Thermodynamic Selection. Karo Michaelian.

Karo Michaelian
'Thermodynamic Dissipation Theory
of the Origin and Evolution of Life',
12th printing, March 2017
What if somebody told you that a deadly substance such as radioactivity or UV light  actually was involved in the origin of life? We all know that a small amount of UV-C light could instantly kill most present day micro-organisms. We all know that the ozone shield is vitally important to life because it absorbs biologically harmful ultraviolet (UV) radiation from the sun. We all know that melanin in our skin absorbs the energy of UV light and shields our cells from the radiation’s harmful effects (source). If we know all this, how on Earth could somebody think that UV light plays a role, let alone a key-role, in the origin of life? You probably think such a person is ignorant or a genius.

There is such a person in Mexico. It is physicist Karo Michaelian. He called his theory Thermodynamic Dissipation Theory of the Origin and Evolution of Life. His view of life is a radical new theory about life and evolution based on the theory of dissipative systems. A dissipative system is a thermodynamically open system which is operating far from equilibrium in an environment with which it exchanges energy and matter. Examples of dissipative systems are hurricanes and living organisms. I am intrigued. I want to know more about it. Even if the theory only partially solved the origin of life, it would be a great contribution to science.

UV-resistant RNA and DNA

Michaelian applies the theory of dissipative systems to the origin of life with interesting results. He points out that [1] both RNA and DNA are exceptionally strong absorbers and extremely rapid dissipaters of ultraviolet light UV-C (230–290 nm) [2]. They do this within a picosecond, which is extremely fast (one millionth of one millionth of a second). There are no known other biotic or abiotic molecules that have this property, he claims. UV-C light from the sun could have penetrated the prebiotic atmosphere 4 to 2.5 billion years ago. The reason is that the ozone-layer (ozone shield) did not exist at the time [3], so UV-C light could not be absorbed by the ozone layer. This is before the origin of life. So, Michaelian suggests that DNA and RNA have those exceptional properties because they could resist the UV-C light of those days. In other words: DNA and RNA (especially the 5 bases) were thermodynamically selected. They were stable under those harsh conditions. If DNA and RNA have indeed those properties it makes sense that they were selected. Not only DNA and RNA: "There are also many other vestiges remaining in the fundamental molecules of life pointing to a UV-C environment at, or very near, the beginnings of life which would also have to be considered as mere accidents or coincidences..." (p. 307). This all makes sense and this is one of the potential valuable contributions to the Origin of Life field.

So, the explanation of why DNA has been 'chosen' as the hereditary molecule, is that it has been thermodynamically selected at a time 4 to 2.5 billion years ago. A relic of the past. This seems plausible because all molecules of those days must necessarily have been very resistant to UV light. You cannot call it natural selection, because we are talking here about non-living non-reproducing molecules. I guess other molecules were destroyed, but Michaelian does not tell us much about what happened for example with amino acids, peptides, proteins, lipids, sugars, etc. in those days.

Now we have short sequences of DNA or RNA. But that is not life. DNA should be replicated. Michaelian has ideas about that too ('Ultraviolet and Temperature Assisted Replication'). Still, this does not amount to life. But all other Origin of Life researches face the same problem. Michaelian is not the only scientist claiming a role for UV light.  John D. Sutherland reports that his team created nucleic acid precursors starting with just hydrogen cyanide (HCN), hydrogen sulfide (H2S), and ultraviolet (UV) light [4]. I don't know what the specific role of UV is in their scenario.

I am not an expert on these matters, so I have to rely on the opinion of Origin of Life researchers. I found a few isolated remarks which seem to support Michaelian. For example Koonin et al (2006): "... suggest that photosynthesis originated in the cyanobacterial lineage under the selective pressures of UV light and depletion of electron donors". That is similar to the main claim of Michaelian. There is a short supporting remark in Leslie Orgel (1973) [5]. However, these are a few isolated remarks. Almost universally, when in the Origin of Life and evolution literature UV light or the ozone layer is mentioned, UV light is harmful. For example: "the damaging effects of solar UV, which was orders-of-magnitude stronger in the absence of the ozone shield than it is now" (source). And: "Skin cells that produced a pigment called melanin were advantaged because melanin is a natural sunscreen; it absorbs the energy of UV light and shields cells from the radiation’s harmful effects." ( source ).
Famous origin-of-life researcher Cairns-Smith wrote: "It is being realised too that ultraviolet sunlight is even better at destroying middle-sized organic molecules than at making them" [6]. On the other hand, if UV creates ozone O3 from O2 that seems to be a creative process. Maybe that is a clue [17].

Returning to our remarks at the beginning of this blog. It still remains puzzling that UV light causes mutations, causes skin cancer [7] and is widely used as an sterilization method (anti-bacterial), is implicated in mass extinctions [8], and at the same time  –according to Karo Michaelian– is instrumental in the production of the first molecules of life and at the same time according to mainstream science small amounts UVB radiation help synthesize vitamin D. How does this all fit together? Is it possible that proto-life was not damaged, but life today is damaged by UV? [19].

I would like to see experimental results with UV-C induced DNA and RNA synthesis published in a peer-reviewed scientific journal. Such an experiment would not be too complicated I guess. If successful that would be a major breakthrough in the origin of life field.

Poor Photosynthesis

Now the most remarkable claim of all. Applying his theory to photosynthesis: Karo Michaelian observes that photon dissipation into heat accounts for 99,9% of the free energy in sunlight and only 0,1% is used for photo-synthesis (p.70, p.312) [9]. This is a crucial fact in his thinking:
"This represents an extremely poor efficiency for a photosynthetic system that has had the opportunity to evolve for at least 3,500 million years considering that humans have developed systems capable of converting up to 40% of the free energy in sunlight into usable electrical energy within only 40 years of technological innovation." (p.312)
Michaelian concludes from these data that not photosynthesis, but photon dissipation into heat has the highest priority of plant species. It is not natural selection that rewards plant species with the highest photosynthetic efficiency, but it is the law of dissipative systems that selects plants with the highest dissipation [10], [11]. Needless to say this is completely against the common sense and the Darwinian view of life [12].

His entire argument hinges on the assumption that it is possible to distinguish optimization of biomass production from optimization of the conversion of visible light into infrared light (heat). He claims thermodynamic dissipation is optimized and photosynthesis is not. However, if both processes are necessarily connected, then it is not possible to distinguish between the two, let alone to point to the one that is optimized! I think that they are two aspects of the same process. Two points of view that can not conflict and are both true.
Obviously, Michaelian would counter that the number 0,1% is decisive. It is just too small to be an optimum [18]. But the number alone is cannot be decisive. We need to know whether is physically, chemically and biology possible at all to have a significantly higher efficiency. How can we know this? Comparing photosynthesis with solar panels is certainly no good. The purpose of solar panels is electricity production and nothing else. Plants do not produce electricity. In contrast with solar panels, photosynthesis means synthesis of carbon compounds (sugars) using CO2 + H2O + photons. Solar panels are not in the business of synthesizing carbon compounds. So, that comparison is wrong.

The conclusion that 0,1% is too low, is just as wrong as concluding from the fact that 98% of the human genome is non coding, that the function of the human genome is garbage collection. Or conclude from the high energy consumption of the brain that the purpose of the brain is heat production. Or conclude from the inefficiency of light bulbs and fossil fuel cars that the main purpose is heat production [16].

Despite 0,1% being a low number, it is enough for all life on earth. More than 7 billion people and even a larger number of cats, dogs, cattle and wild animals depend on photosynthesis. 

A better idea would be comparing natural photosynthesis with artificial photosynthesis. The highest reported efficiency for artificial photosynthesis lab prototypes is 22.4%. However, plants are efficient in using CO2 at atmospheric concentrations, something that artificial catalysts still cannot perform (wikipedia). (Plants cannot control CO2 in the atmosphere!). So, until now natural photosynthesis still outperforms artificial photosynthesis. 
Even if humans could significantly improve artificial photosynthesis, it would be comparable to improving milk production in cattle. It would not prove that milk production of wild cattle is inefficient. There are evolutionary and ecological reasons for this.
Improving Photosynthetic Efficiency for Greater Yield
source
In modern evolutionary theory the definition of fitness is reproductive success. (I will return to that and what Karo Michaelian writes about it in the next blog). If photosynthesis would be the only factor determining reproductive success it is expected to be optimized or even maximized. But photosynthesis is not the only factor. For example Nitrogen availability is an important factor for growth (source). And there are other ways to enhance biomass production. Plants can make few bigger leaves, or many smaller leaves. It at all depends on the design specifications: for a shadow environment or the bright sun? Also CO2 is a limiting factor for photosynthesis and is out of control of a plant. Life history theory aims to explain the facts that different organisms have different strategies for growth and reproduction. Weeds (annuals) have fast growth and short lives, trees have slow growth, live long and invest heavily in non-photosynthetic wood en root system. [13] Bamboo is a famous fast growing plant [14] (whatever the photosynthetic efficiency).

Even if photosynthesis were the only factor in evolutionary fitness, it would not necessarily mean that the efficiency would be high. The reason is that there is enough sunlight. Literally more than enough. Whenever there is more than enough of a resource, there is no reason to have high efficiencies. "Crop leaves exposed to full sunlight absorb more light than they can use. If they can’t get rid of this extra energy, it will actually bleach the leaf. Chemical changes within the leaf allow the excess energy to be dissipated as heat, in a process called nonphotochemical quenching (NPQ)" (source). I think this is  an important reason why the efficiency is 'low'. See also: Photo-inhibition, photoprotection.

Thermodynamic Limit. There is an intriguing reason why photosynthesis is not 100% efficient: thermodynamics! There is a Thermodynamic Limit: "At the reaction centers, thermodynamics limit the amount of energy available to do photosynthetic work."! (source), (source). I would like Karo Michaelian's comments! As a physicist he should be able to enlighten us.

Conclusion. The function of photosynthesis is carbon fixation: the most fundamental biological reaction which incorporates carbon atoms into organic molecules starting with carbon dioxide. Without carbon fixation no plants, no animals, no biosphere. We animals cannot live from the sun! We need photosynthesis because of the food it produces for us. We don't care if plants produce entropy when we are hungry. We cannot eat entropy.
However, his thermodynamic view is not wrong. All organisms are open thermodynamic systems that necessarily produce entropy: bacteria, plants and animals. Michaelian unnecessarily claims that Darwinian natural selection contradicts his 'thermodynamic selection', and natural selection should be replaced by 'thermodynamic selection'. More on that in the next blog. In this respect his views are over the top. He pushed it too far. That's a pity.

Michaelian cites another two experiments purportedly proving his theory. The first is 'A maximum hypothesis of transpiration in plants' (ref 392). This won't work in a hot, dry climate because plants would die if the tried to maximize evaporation. Second: 'Inactive Photosystem II Complexes in Leaves' (ref 47). However, the authors of the article conclude: "Although there are two few data to answer the question of whether inactive centers serve a useful role in photosynthesis, for example in photoinhibition, development, or otherwise, ..." (GK: 'two' must be 'too'). So, there is more research required to find out their functions.
In the end reading his book is a pleasure and is not a wast of time. It contains many illustrations, more than 400 notes, a detailed index, glossary and is very cheap for a scientific book. His alternative view of life may be unusual, even weird, it highlights facts which are not yet well explained by Darwinian theory such as why plants devote resources to the synthesis of reaction centers that apparently do not contribute to carbon fixation (p. 312) and the red-edge effect. I was not familiar with these facts.

Genetically modified plants are better able to make
use of the limited sunlight available when
 their leaves go into the shade (source)

Others about Dissipative Systems and Life

To my surprise physicist Jeremy England said "when a group of atoms is driven by an external source of energy (like the sun or chemical fuel) and surrounded by a heat bath (like the ocean or atmosphere), it will often gradually restructure itself in order to dissipate increasingly more energy". This is the same idea as Michaelian.
Also to my surprise Eric Schneider and Dorion Sagan (2005) Into the Cool use often the same idea and wordings as Karo Michaelian. This one is beautiful:
"Go out and observe trees, and you will see living dissipative systems stretching skyward to capture available solar energy. ... This process is the result of the thermodynamic imperative to degrade the quality of the incoming solar energy as completely as possible." "Plants are perhaps the most advanced instrument yet evolved for degrading incoming solar radiation." (p.220).
Michaelian certainly would agree.



Notes

  1. He points out that: See wikipedia article 'Abiogenesis'. The wording, the language, the style of the section 'Thermodynamic dissipation' are the same as in Karo Michaelian's book. So, probably Karo Michaelian wrote that section. It is a summary of the theory that only its author could have written. Or: it is a copy&paste work of somebody else.
  2. UV-C: Today UV light is used to kill bacteria! See: wikipedia article Ultraviolet germicidal irradiation. On the wikipage DNA there is nothing about DNA's exceptional resistance to UV-C. On the contrary: wikipedia tells us that UV-B damages DNA and causes mutations.
  3. Ozone layer appeared when oxygen levels were high enough (Great Oxygenation Event)
  4. Common origins of RNA, protein and lipid precursors in a cyanosulfidic protometabolism Nature Chemistry volume 7, pages 301-307 (2015)
  5. L.E. Orgel (1973) The Origins of Life,  p. 117: "However, it has been shown that if hydrogen sulfide or formaldehyde were present in sufficient quantities in the atmosphere, they could have absorbed a much larger amount of ultraviolet energy and made it available for the synthesis of organic compounds." but also here: "ozone absorbs ultraviolet light strongly ... otherwise men would be subjected to very harmful doses of ultraviolet light."(p.117). There there seems to be universal agreement  (1) there was no ozone layer at the origin of life, (2) UV light was hitting the earth surface, (3) UV is harmful. (added 2 May 2018)
  6. A. G. Cairns-Smith Seven clues to the origin of Life, 1985, p. 42.
  7. "No type of UV radiation has been shown to be safe – cancers have developed after exposure to UVA (alone), UVB (alone), and UVC (alone)." Source: Does UV radiation cause cancer? from the website www.cancer.org of the American Cancer Society. So, this is a serious source. Further, see the website of the Skin Cancer Foundation: UVC isn't a concern for skin cancer.
  8. See chapter 4: An ancient ozone catastrophe? in: David Beerling (2007) The Emerald Planet. (my review).
  9. p.70: KM quotes the lowest Photosynthetic efficiency. But it ranges from 0,1% – 1% to 2% (crops). Nonetheless: it seems to be low. KM emphasizes that everybody ignores this fact (p. 283). This is not true: "a surprising small amount of that energy is turned photosynthetically into biomass." (Eric Schneider, Dorion Sagan (2005) Into the Cool, p.221) however these authors don't draw very dramatic conclusions from this fact.
  10. "Instead, if plants and other photosynthetic organisms have evolved to optimize dissipation rather than photosynthesis ...". (page 234).
  11. Plants could not exist without carbon fixation. If carbon fixation is against universal law of dissipation-maximization then photosynthesis could not have originated in the first place.
  12. The 'purpose' of photosynthesis is the synthesis of carbon-compounds as glucose and ATP. Carbon-based life could not exist without photosynthesis.
  13. Photosynthetic efficiency is not a fixed number. For example the photosynthetic efficiency  of oak forests drops from 1.5% - 1.7% at ages between 20 - 40 years to 0.4% at the age of 200 years (Schneider and Sagan, 2005, p.221).
  14. Growth pattern and photosynthetic activity of different bamboo species growing in the Botanical Garden of Rome.
  15. The tile of this blog 'The Origin of Species by Means of Thermodynamic Selection' is of course a paraphrase of Darwin's 'On the Origin of Species by Means of Natural Selection'.
  16. added May 2 2018: I couldn't believe when I first heard that the fuel efficiency of a fossil fuel car was only 25%! An invention some 100 years on the market! 
  17. remark added May 2 2018
  18. If you believe in intelligent design: the extremely low efficiency of photosynthesis is an insult to the Creator. Creation is perfect. So, it must have happened right after the fall. Before the fall plants had a maximum efficiency only constrained by the laws of physics. (added 3 May 2018)
  19. In an email 17 May 2018 Karo Michaelian wrote: "in the book I do in fact "explain why in contrast to mainstream opinion UV is not harmful". I do that particularly in sections 4.2 (Of Pigments and Protectionism) and 19.13 (Pigments Provide Protection) and in many other places throughout the book."  [added 17 May 2018]

04 April 2018

Klaas Landsman (3) Finetuning versus de tweede hoofdwet van de thermodynamica

relatie Finetuning — Life —
— Second Law of Thermodynamics

Vraagje: is de Tweede Hoofdwet van de Thermodynamica ('Second Law of Thermodynamics') strijdig met Finetuning for Life? Om die vraag te beantwoorden moeten we eerst een andere vraag stellen: is het verschijnsel leven strijdig met de tweede hoofdwet?

Voor zover ik weet zijn finetuning en de 2e hoofdwet niet eerder met elkaar in verband gebracht. Klaas Landsman (zie vorige blogs) heeft het ook niet gedaan [5]. En ik heb het ook niet in de literatuur gevonden.

tweede hoofdwet strijdig met leven of niet?

Finetuning is: de fundamentele fysische constanten hebben zodanige waardes dat chemie en leven mogelijk zijn. Dat is weinig controversieel. Dat is een onmiskenbaar feit. Prima! Maar, het is óók zo dat de 2e hoofdwet noodzakelijkerwijs voortvloeit uit de aard van diezelfde materie die gefinetuned zou zijn voor leven. En die 2e hoofdwet zegt:

"De entropie (wanorde) van het heelal neigt naar een maximum".
of:
"Orderly things tend to become disordered over time"
                       (David Deamer, 2011, First Life, p.99)
Voorbeeldje: doe een theezakje (inkt, zout, suiker) in een kopje water. Eerst zijn de toegevoegde moleculen geconcentreerd in 1 locatie, en vrij snel spreiden ze zich uit over het beschikbare volume met als eindresultaat een homogene vloeistof. Bovendien neemt het vrij snel de omgevingstemperatuur aan. Dat is de tweede hoofdwet. Als dat de tweede hoofdwet is, dan hebben we een probleempje. 

Kijken we naar de definitie van het leven:
"Living systems are able to establish order within a chaotic world and perpetuate that order as long as energy is available for resisting the inexorable tendency toward increased entropy.
Dirk Schulze-Makuch, Louis Irwin (2006) Life in the Universe, p.16) (inexorable = niet te stoppen).
NB: dit is geen selectief citaat of controversiële definitie. Ik heb vele definities van 'leven' vergeleken [4], ze komen allemaal op hetzelfde neer. Veel definities leggen andere accenten (zoals het belang van DNA, eiwitten, membraan), maar geen enkele is in strijd met bovenstaande definitie. De definities zijn afkomstig van onderzoekers in het Origin of Life / Astrobiology gebied, die zich niet bezighouden met finetuning for life.

Conclusie: het leven gaat tegen de 2e hoofdwet in. Oorzaak: het leven is een onwaarschijnlijke, en complexe structuur die niet zou kunnen bestaan als er niet voortdurend energie aan toegevoegd wordt [11]. Het leven is een pannetje met water dat kokend gehouden wordt op een vuurtje (=energie). Het leven is een systeem dat niet in evenwicht is met zijn omgeving ('Non-Equilibrium Thermodynamics'). Als een lichaam koud aanvoelt en niet meer beweegt: bel 112. Het zijn sterke aanwijzingen dat het lichaam in thermodynamisch evenwicht is met zijn  omgeving. En dus dood.
Paul Davies bracht het heel fraai onder woorden: life is against the tide [5]. Het leven is tegen de stroom in roeien. Geen enkele auteur ontkent dit aspect van het leven.

Let op: het leven is niet letterlijk strijdig met de 2e hoofdwet, want anders zou de 2e hoofdwet gefalsifieerd zijn! [3]. Fysici zouden je uitlachen. De tweede hoofdwet is heilig. Het leven is 'strijdig met' de 2e hoofdwet net zoals het in de lucht hangen van een helikopter 'strijdig is' met de wet der zwaartekracht. Als de brandstof op is, volgt neerstorten en de dood. Net als het leven. Het leven 'omzeilt' de 2e hoofdwet door slimme trucs.
Natuurkundigen lossen deze 'strijdigheid' op door te zeggen: het leven is een open thermodynamisch systeem omdat het energie importeert en afvalstoffen exporteert. De 2e hoofdwet is  van toepassing op gesloten systemen. Natuurkundigen hebben het probleem opgelost, de 2e hoofdwet blijft geldig.

Against the tide

Toch blijft er een ongemakkelijk relatie bestaan tussen de tweede hoofdwet en het leven. In bovenstaande definitie van het leven zien we: "resisting the tendency toward increased entropy"; het leven biedt weerstand tegen degradatie. Als je goed kijkt naar verschillende auteurs dan zie je dit idee steeds terugkomen.
We weten allemaal dat we moeten blijven eten om in leven te blijven. We doen ons hele leven niet anders. Dat is natuurlijk, dat is normaal. Maar als je nadenkt over hoe de fysische natuurwetten in elkaar zitten: is dat wel zo natuurlijk? Had het niet anders gekund? Is de tweede hoofdwet noodzakelijk? Zijn er in andere universa geen levende wezens die niet hoeven te eten? [9]. Dat gaat mijn kennis te boven.

Leven dankzij de tweede hoofdwet?

Eerlijkheidshalve moet ik melden dat er ook wetenschappers zijn die menen dat er een harmonie is tussen het leven en de tweede hoofdwet. Dat zou ook onze kijk op finetuning drastisch kunnen veranderen.

Het idee is dat het leven energie degradatie [6] versnelt. Dus in dezelfde richting werkt als de tweede hoofdwet. Dat doen ze door warmte uit te stralen. Fysisch: het leven is een dissipatieve structuur. Door dissipatie van warmte neemt de entropie van het heelal sneller toe dan zonder leven. Er zijn meerdere auteurs die soortgelijk opvattingen verkondigen [1], [13], [14].

Jeffrey Wicken beweert zelfs dat het leven dankzij de tweede hoofdwet bestaat! [7]. Dat gaat ver. Eric Schneider omschrijft het zo: organismes verbruiken energie waardoor de entropie (=nutteloze warmte, wanorde) in het heelal toeneemt [8] en dat is precies wat de tweede hoofdwet voorschrijft. Dus ook hij zegt dat leven bestaat dankzij de tweede hoofdwet. Mijn kanttekening: organismes streven er in het algemeen naar om rond te komen met zo weinig mogelijk energie, dus om energie zo efficient mogelijk te gebruiken [12].

De ambivalentie van het leven

Niemand heeft de dubbelrol van het leven expliciet aan de orde gesteld. Enerzijds creëert het leven orde, want het leven is orde en anderzijds produceert het leven wanorde omdat het orde en energie uit de omgeving omzet in wanorde en die dumpt in de omgeving. Populair gezegd: het lichaam is een zeer complexe structuur die ongestructureerde poep produceert. Dus je kunt concluderen dat het leven zowel meewerkt aan de 2e hoofdwet, als de 2e hoofdwet tegenwerkt [10].


fine tuning?

Dit alles overziend: is het heelal gefinetuned voor het leven? Het leven is: hier heb je een kano en een peddel, en je mag tegen de stroom op peddelen. Als je te langzaam peddelt stort je met kano in een afgrond van 100 meter. Dood. Naar mijn smaak is dat niet een bio-friendly cosmos! Een optimist zegt: als er geen stroom is kun je er ook niet tegen in peddelen. Dit heelal is het best mogelijke heelal.

Maar zelfs als er geen alternatief voor de tweede hoofdwet mogelijk is in een multiversum, blijven we zitten met een compromis. Het heelal is niet ideaal voor het leven. Bewijs: als je niet eet ga je dood. Plus: eten is doden. Wat een drama! Wie heeft dat verzonnen? Zelfs auteurs die de harmonie verdedigen schrijven verderop dat het leven de tweede hoofdwet moet weerstaan (resisting).
Dus, ik kan met de beste wil ter wereld niet zeggen dat het heelal optimaal en compromisloos gefinetuned is voor het leven. En dan heb ik het nog niet eens gehad over het ontstaan van het leven! Als het ontstaan van het leven en fluitje van een cent was, als er overal in het heelal spontaan leven zou ontstaan, dan zou dat beter passen bij een heelal dat gefinetuned was voor het leven. Hoezo: speciale condities voor het ontstaan van leven? Hoezo een planeet in de habitable zone? Zijn andere planeten in het gefinetuned heelal ongeschikt voor leven?

Vorige blogs

 

Noten

  1. Rod Swenson geciteerd in Lynn Margulis, Dorion Sagan (1995) What is Life? p.16. Rod Swenson: "...because it is through ordered, dissipative systems that the rate of entropy production in the universe  is maximized." [1]. Maar ever verder: "Life must maintain itself against the universal tendency of heat to dissipate with time." (p.86) en: [animals] make wast of useful energy ..." (p.151). Rod Swenson ziet leven als doelgericht omdat het helpt om het universum als geheel grotere entropie te krijgen!
  2. In de Westerse wereld kennen we geen honger meer, daardoor is de 2e hoofdwet ook een ver van mijn bed show. Maar vroeger en in Afrika is er nog steeds hongersnood, dus confrontatie met de 2e hoofdwet.
  3. Schrödinger paradox (p.7 Schneider): het leven is ogenschijnlijk in strijd met de tweede hoofdwet.
  4. In mijn review van Tibor Gánti staat een lijst van 27 definities van leven. Hier is er nog een: "Associated with self-replicating far-from-equilibrium systems is an energy requirement. There is a constant thermal degradation, driven by the second law of thermodynamics, toward equilibrium that must be countered by the expenditure of work. Thus, there is the requirement of a proper energy source and the ability to convert that energy into a form that is useful in maintaining the structure and synthesizing similar structures." Harold Morowitz (1999) 'A Theory of Biochemical Organization, Metabolic Pathways, and Evolution', Complexity pp 39-53.
  5. Ook fysicus Paul Davies (2006) The Goldilocks Enigma - Why is the Universe Just Right for Life? (gaat dus over finetuning) behandelt niet de mogelijke problemen die de tweede hoofdwet op kan leveren voor het leven. Echter in The Fifth Miracle (1999) legt hij op fraaie wijze uit dat leven en de tweede hoofdwet niet strijdig zijn. Maar de titel van Chapter 2: 'Against the tide' spreekt voor zich (tegen de stroom in!). Dus als hij met finetuning bezig is vergeet hij dat het leven against the tide is! Toeval?
  6. Robert Hazen (2005) Genesis, The Scientific Quest for Life's Origin, p.13-14.
  7. "Wicken (1987) who dares to claim that it is only because of the second law of thermodynamics that life exists at all." ; "Wicken persuasively argued that the second law is not just compatible with life but instrumental in its origin and evolution." (Eric Schneider, Dorion Sagan, 2005, p.105.)
  8. Eric Schneider, Dorion Sagan (2005) Into the Cool: "In using up energy, in performing work, they perform a natural function: the production of entropy mandated by the second law (p. xv). Schneider gaat zover als: "Life as a manifestation of the second law of thermodynamics". Dat gaat wel wat ver, want leven zelf is orde. En: "They don't just obey that law, they actively enhance its operation. (p.xv); "accelerate the natural production of entropy.". En: "Life not only does not contradict the second law but exists because of it." (p.330 Schneider). Dat gaat te ver naar mijn smaak.
  9. Adam en Eva plukten vruchten in het paradijs. Dat bewijst dat je zelfs in het paradijs moet eten om in leven te blijven. Dus de tweede hoofdwet gold ook in het paradijs. Zou je in de hemel ook moeten eten, of geldt daar de tweede hoofdwet niet? Leven zou daar een perpetual motion machine (Trotman) zijn! Een hindernis om het probleem te zien is dat we eten lekker vinden en er daarom niet over nadenken waarom we moeten eten.
  10. Hetzelfde kun je zeggen van de moderne beschaving: we produceren auto's, vliegtuigen, computers (bitcoin-miners vreten stroom!), etc. Die produceren ontzettend veel entropie. Dus die accelerate, enhance de tweede hoofdwet!
  11. Fijne structuur op moleculair en cellulair niveau: die wordt door een simpele kogel vernietigd met de dood als gevolg. Bewijs geleverd dat die structuur nodig was voor het leven. 
  12. Denk aan vogeltrek. Dat is topsport. Individuen die het efficiëntst met energie omgaan komen het verst. Denk ook aan de actieradius van elektrische auto's. Denk aan LEDs. Denk aan de evolutie van zonnepanelen en windturbines.
  13. De theorie van de fysicus Karo Michaelian (2016) is volledig gebaseerd op het idee dat het leven bestaat dankzij energie (entropy) dissipatie: Thermodynamic Dissipation Theory of the Origin and Evolution of Life. Samengevat: Life started by dissipating UV photons into heat! Het is een extreem reductionistische, ééndimensionale en ambitieuze theorie over het leven: alles wordt gereduceerd tot dissipatie. Ik kom hier nog op terug in een volgende blog, want het is wel een fascinerende theorie en je leert er (als bioloog) veel nieuwe feiten door. Zie: zijn website. [8 april 2018]
  14. Clive Trotman (2004): "The laws [of thermodynamics] do not work against the origin and existence of of life but overwhelmingly in its favor" (p.112). [toegevoegd 9 april 2018]

19 March 2018

Klaas Landsman (2). Het zgn. fine-tuning for life argument

Klaas Landsman (2018)
Naar alle onwaarschijnlijkheid.
Klaas Landsman (2018) geeft in zijn boek Naar alle onwaarschijnlijkheid een zeer goede uiteenzetting van finetuning van de kosmos voor het leven. De Hoyle-resonantie was niet alleen het eerste voorbeeld van de finetuning, maar tevens de enige echte voorspelling van finetuning [1].
Ik vind finetuning een fascinerend onderwerp. Het heeft alles te maken met Big History (verbanden leggen!), evolutie en creationisme. Ik zou er nog vele blogs over kunnen schrijven.

Ik geef hier enige aanvullingen op de uitstekende uiteenzetting van Landsman.

Finetuning for what?
Landsman noemt het finetuning for life argument een understatement, omdat het niet alleen fine-tuning for life zou zijn, maar voor alle materie, en zelfs voor het bestaan van het universum zoals wij dat kennen. Ik noem het een overstatement precies omdat er te véél wordt geclaimd. En omdat ze het totaal niet kunnen waar maken.

Als je goed kijkt naar het finetuning for life argument, dan blijkt dat het helemaal geen finetuning for life is, maar hoogstens fysische finetuning voor de bouwstenen C, H, N, O, P, S van leven. Finetuning specifiek for life kan dus helemaal niet. Dat is een misverstand dat gretig in leven wordt gehouden door religieuze denkers. Bovendien, als er echt finetuning for life zou bestaan dan zou je moeten verwachten dat het leven op een planeet zoals de aarde spontaan zou ontstaan. Maar wat blijkt? Na al die onvoorstelbaar precieze finetuning van de fysische natuurwetten moet de Schepper-God het leven op aarde alsnog handmatig creëren (Genesis). Wat een afgang. Een ingreep in de natuurwetten! Dus, de hele uitdrukking 'de kosmos is gefinetuned for life' klopt niet en gelovigen gaan er niet consequent mee om. Ik noem het dus een overstatement.

David Foster (1993)
The Philosophical Scientists
Evolutie
Religieuze denkers richten hun aanvallen ook in de context van de evolutietheorie op kleine kansen. Onlangs kreeg ik nog een onthullend commentaar op een oude bespreking op mijn WDW website van een creationistisch anti-evolutieboek (de moeite waard om over te bloggen). Het argument draaide om de extreem kleine kans dat een hemeglobine eiwit door zuiver toeval zou ontstaan: 10 tot de macht 650. Zo werkt evolutie niet. Maar zo werken de argumenten tegen evolutie bijna altijd. Toen realiseerde ik mij dat ook het finetuning argument draait om extreem kleine kansen. In feite zijn volgens mij alle creationistische en Intelligent Design (ID) argumenten gericht tegen  extreem kleine kansen, dus tegen toeval. Religieuze denkers zien extreem kleine kansen en roepen: dat kan geen toeval zijn! Dat moet God zijn!

Heelal: een reality check
 
Een volgend probleem met het the cosmos is fine tuned for life is dat die extreem kleine kansen zo oogverblindend zijn, dat de kille feiten van het heelal aan het oog onttrokken worden. Het heelal is bepaald niet een extreem efficiënte en doelmatige machine om leven voort te brengen, laat staan 'intelligent leven'. Ik zet een paar voorbeelden op een rijtje ter illustratie:
  1. Het heelal is een onmetelijk grote, koude, donkere en vrijwel lege ruimte waar het bepaald niet wemelt van het leven. Fine tuned for life?
  2. het zichtbare heelal heeft 100 miljard melkwegstelsels met ieder 100 miljard sterren. Zijn die allemaal nodig? Moeten we dat verwachten onder de finetuning (ft) hypothese?
  3. 95% van het heelal bestaat uit zgn. donkere materie en energie: wat voor nut heeft dat voor het leven? Idem: zwarte gaten (black holes).
  4. De belangrijkste chemische elementen voor het leven zijn: Koolstof (C), Zuurstof (O), Stikstof (N), Fosfor (P), etc. en die werden niet geproduceerd door de Big Bang. Die werden pas veel later in de geschiedenis van het heelal geproduceerd. Is dit begrijpelijk onder de ft hypothese?
  5. Het heelal bestaat voor 75% uit waterstof (H) en 25% Helium-4. Een objectieve waarnemer zou moeten concluderen dat deze kennelijk de belangrijkste elementen zijn. Maar volgt dat uit de ft hypothese?
  6. Als je het Periodiek systeem der elementen bekijkt (zie hier onder) dan zie je dat slechts 19 van de 115  van de elementen essentieel zijn voor menselijk leven (paarse kleur in illustratie). Wat is het nut van de rest? Dat lijkt niet op een doelgerichte, efficiënte finetuning for life.

  7. Essential Elements for Life (paars). groen: mogelijk essentieel.
    grijs: niet essentieel of relevant voor leven.

  8. Levende organismen gebruiken 20 aminozuren terwijl er minimaal 80 aminozuren bestaan ("over 80 amino acids created abiotically in high concentrations and about 900 are produced by natural pathways"; source). Hoe verklaart finetuning for life dit?
  9. Alle golflengtes van UV licht van 220 - 390 nm (UV-C, UV-B, UV-A) veroorzaken mutaties in het DNA. UV-B licht produceert pyrimidine dimers, dat is schadelijk. Dus: DNA en de zon als energiebron voor onze planeet, zijn niet op elkaar afgestemd. Zie: DNA damage.
  10. Kan het zijn dat de planeet Aarde een beetje té gevoelig is voor opwarming door CO2? Is dat compatibel met de ft hypothese?

De chronologie

An updated time line of the universe shows the first stars
being born by about 180 million years after the big bang.
bron
Een vraag: ziet het er naar uit dat de mens het doel van het universum is? De Schepper-god zou met extreme precisie aan enkele tientallen knoppen gedraaid hebben en dan:
  • de eerste 150 miljoen jaar van de geschiedenis van de kosmos heerste er volledige duisternis (Chronology of the universe). [4] Was dat nodig?
  • ons zonnestelsel (zon, aarde, etc) heeft zich pas 4.6 miljard jaar geleden gevormd, dus pas na 9,1 miljard jaar. Waarom duurde dat zo lang als ons zonnestelsel zo belangrijk is?
  • Boring Billion is een periode van een miljard jaar na het ontstaan van het leven op aarde zien we alleen eencelligen. Pas vanaf 600 - 500 miljoen jaar geleden zien we meercelligen. Moeten we dat verwachten onder de ft hypothese? Idem: snowball earth, mass extinctions; late atmospheric oxygen arrival.
  • Als de mens 'de bedoeling was', waarom duurde het zo'n slordige 3,5 miljard jaar na het verschijnen van het eerste leven op aarde dat de mens verscheen? (zie bekende klok figuur hieronder )
  • History of Earth in 24-hour clock
    de mens verschijnt de laatste paar seconden
  • Als het leven in het heelal de bedoeling is, waarom dan de warmtedood van het heelal? (heat death of the universe).

Leven is tegennatuurlijk
Een belangrijk en relevant punt dat Landsman in het geheel niet noemt:
  • het verschijnsel leven is in feite 'tegennatuurlijk'. Leven is een semi-stabiel verschijnsel dat alleen kan blijven voortbestaan door voortdurend materie en energie (=voedsel) uit de omgeving te importeren. Per definitie. Houdt die toevoer op dan vervalt het leven snel tot dode materie. Het lijkt heel vanzelfsprekend dat we moeten eten om in leven te blijven, maar het is tegelijk het ultieme bewijs dat het leven tegennatuurlijk is. Waarom? Door een zeer fundamentele natuurwet: 'The Second Law of Thermodynamics'! Leven is een far-from-equilibrium state [2].  Met als bijkomend nadeel dat organismen (uitgezonderd planten) ander leven moeten doden om zelf in leven te blijven.
OK, het is duidelijk dat leven mogelijk is met de huidige natuurwetten. Maar hoe logisch zijn de huidige natuurwetten als een Schepper leven wil scheppen? Als de kosmos gefinetuned was voor leven, zouden er dan niet meer 'leven-vriendelijke' natuurwetten bestaan hebben? Zoals het nu is, is het bepaald niet elegant ontworpen. Waarom zijn de natuurwetten niet zodanig dat ze inherent stabiele levensvormen mogelijk maken? Dus, zonder dat we continue moeten eten (=doden) om in leven te blijven? De natuurwetten van de kosmos zouden ontworpen moeten worden voor leven en niet voor de dood! [2]

Omgekeerde finetuning
Landsman noemt een paar keer dat organismen zich aanpassen (finetuning) aan de omstandigheden en niet andersom. Dat ben ik met hem eens. Dat is evolutie. Dat is natuurlijke selectie. Zeker een belangrijk punt. Maar de natuurwetten moeten wel zodanig zijn dat ze een complexe (koolstof-)chemie mogelijk maken. Dat is een fysische randvoorwaarde. Daarna past het leven zich aan aan de eigenschappen van de fysica en chemie. Hier is nog veel meer interessants over te zeggen [3].

Metaforen
Ik denk dat ik Landsman goed samenvat met: alle metaforen (kaartspel, etc) door gelovigen naar voren gebracht om finetuning een theïstische interpretatie te geven, hebben een menselijke context: ze bevatten artefacten, en mensen met bedoelingen. Maar dan neem je al op voorhand een Schepper aan. Wat we nodig hebben is een zuiver wetenschappelijke behandeling van finetuning zonder de kwestie te verontreinigen met misleidende, antropocentrische metaforen.

Landsman concludeert dat het Antropische Principe (zwak of sterk) niet leeg, tautologisch of onjuist is, maar ook geen serieuze bijdrage aan een beter begrip van finetuning levert. 

De uiteenzetting van Landsman zal nog jaren de moeite waard zijn om te lezen. Verplichte kost.

Volgende keer over Jezus.

Vorig blog over dit onderwerp

Over het boek Naar alle onwaarschijnlijkheid. Toeval in de wetenschap en filosofie van Klaas Landsman (1)

 

Noten

  1. Landsman noemt nog enkele andere voorbeelden van fine tuning. De voorbeelden van finetuning (hij schrijft finetuning nooit tussen aanhalingstekens!) zijn fysische realiteit, ze zijn echt. Het zijn geen verzinsels van creationisten.
  2. Over dit onderwerp zou ik makkelijk een apart blog kunnen maken. Creationisten vinden dit geen leuke materie. Zie o.a. Addy Pross, Tibor Ganti en Eric J Chaisson (2001) Cosmic Evolution. The Rise of Complexity in Nature. Zeer de moete waard, ook om over te bloggen.
  3. De lichaamstemperatuur van 37 graden is op de meeste plaatsen op aarde hoger dan de omgevingstemperatuur. Waarom 37 graden? Het kost energie om dat temperatuurverschil te handhaven (vooral 's winters!). Had dat niet anders gekund? Het zou minder energie kosten als de lichaamstemperatuur gelijk is aan de omgevingstemperatuur. Bijvoorbeeld als de temperatuur op aarde overal 37 graden zou zijn.
  4. Recente info: "...the earliest stars didn’t turn on until about 180 million years after the big bang..." bron