07 November 2020

Low Photosynthetic Efficiency? Replacing the agricultural paradigm with the evolutionary paradigm

Dr Matt Johnson: Why is Photosynthesis so inefficient?

I was searching for authors complaining about the low efficiency of photosynthesis. This is a good example:

"Why is Photosynthesis so inefficient? Only 5% of the sunlight that hits this field ends up in these grains. Given that plants have a head start of about a billion years, why haven't they already evolved photosynthesis to be more efficient? ...(Plants have different priorities than us!)" (Dr Matt Johnson)

Dr Matt Johnson asks the question Why is Photosynthesis so hopelessly inefficient? while sitting in a field of grain! Not in a tropical rainforest. Clearly, the question arises in an agricultural context. The human point of view. We need to produce more food for the growing world population and end hunger. Higher photosynthetic efficiency means more food for us humans. Plants don't meet human needs.

Wild strawberry Fragaria vesca
wikipedia Ivar Leidus - Own work, CC BY-SA 3.0,
 

cultivated strawberry (source)
 

When we think of strawberries we automatically think of the big strawberries in the supermarket. But we tend to forget that our big, delicious strawberries started long ago as small wild strawberries. See pictures above. In fact, all our modern cultivated fruit and vegetable species were once small. But, we want bigger tomatoes, bananas, potatoes and grains. This is the standard agricultural paradigm nearly everybody is unconsciously using when we see percentages of photosynthetic efficiency which are closer to 0% than 100%.

This agricultural point of view can also be found in a supposedly neutral wikipedia article about the efficiency of photosynthesis:

"Many plants lose much of the remaining energy on growing roots."

Lose energy? How can a plant exist without roots? Something is seriously wrong here. This is a myopic agricultural view of plant anatomy and physiology. The wikipedia article is apparently written from an anthropocentric point of view: roots of most crop plants are not eaten and thus a waste! Why plants need roots follows directly from the definition of photosynthesis (see below).

Although the Britannica gives a neutral definition of photosynthesis, and there is some attention to 'the needs of the whole plant', the agricultural context is already present in the introduction ('agricultural revolutions').

The Life of a Leaf
The Life of a Leaf
But we can also find the idea of low photosynthetic efficiency outside the agricultural context. Biologist Steven Vogel writes:

"Photosynthesis consumes no more than perhaps 5 percent of that energy [= after rejecting almost all the near-infrared portion of sunlight], an amount we'd dismiss as negligible were it not for life's total dependence on it. That other 95 percent makes trouble. Odd idea, admittedly –light as bad for leaves." The Life of a Leaf, 447/990.

This is remarkable and unexpected, because Vogel wrote a insightful book about plants The Life of a Leaf  in which he exhaustively lists all physical constraints of leaves and the adaptations to deal with them [1]. I will return to him.

Karo Michaelian

Physicist 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:

"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." [2], [19]

Many claims in one sentence! I will debunk all of them. 

An authoritative article in Science states that:

"Solar energy conversion efficiencies for crop plants in both temperate and tropical zones typically do not exceed 1%" [18]. Please note the agricultural context: crop plants [25].

When all the reported photosynthesis efficiencies seem to be low, that is for me a reason to dig deeper. Because it is somewhat surprising.


A number between 0 and 100

For a start, such a simple thing as expressing photosynthetic efficiency as a percentage from 0 to 100 can be quite misleading. It suggests that 100% is the maximum efficiency. Wrong. The calculated theoretical maximum energy efficiency of photosynthesis is 26 percent [7]. So, we should not express the efficiency as a fraction of a physical impossible maximum of 100%, but of the maximum that is set by the laws of physics and biochemistry. Those laws cannot be broken. They set the absolute upper limit. If we use the upper limit, the 26% is the maximum and in a sense represents 100%. So, the 5% efficiency is in fact 20% (5/26). If we use the value 11% in wikipedia [8], than photosynthesis achieves 42% of the maximum. So, it makes more sense to express the efficiency relative to what is physically possible. Karo Michaelian uses 0,1% efficiency which is 1/1000. Indeed, that is negligible! (Hmmm, my income is negligible compared to that of a billionaire.)


Why are solar panels so inefficient?

wikipedia solar panels

We must first debunk the 'solar-panels-are-more-efficient-than-photosynthesis' claim before we can make any progress. The following statements can be found on a website of a company that produces solar panels (a company that hardly can be accused of being pessimistic about performance): 

"Most typical silicon solar cells have a maximum efficiency of around 15 percent. (...) excess energy will be released as heat. This is one of the reasons that solar cells have such a low efficiency; they only need a very specific amount of energy in order to work. (...). 23 percent of the energy from the sun has a wavelength too long to be useful to solar panels. (...) Other wavelengths have some excess energy. In fact, another 33 percent of the sun's energy is excess energy that is also unusable for silicon solar cells. Therefore, this leaves only 44 percent of the sun's energy available to silicon solar cells. More of this energy is lost due to reflection and other processes in the cell itself. Hence, while the theoretical maximum efficiency may be higher, the real efficiency of silicon cells is usually around 15 percent." [16]. [my emphasis]

That means that 85% of the solar energy is wasted! Karo Michaelian (2016) quotes the highest efficiency for solar panels he could find: 40% efficiency. For photosynthesis he chose the lowest value he could find: 0.1%. That is a biased description. Real-life conditions of solar panels must be included in the calculation such as seasons, weather, temperature, the accumulation of dust, grime, and pollen and the problem of shade. No surprise, solar panels and photosynthesis have some efficiency problems in common caused by the laws of physics

Solar panels are less efficient at higher temperatures

Solar panel efficiency drops by around 0.05 percent for every degree Celsius increase in temperature. That is the temperature of the solar panel itself. So, from 25°C to 45°C the efficiency drops with 1% [26]. The ideal day for a solar panel is actually cold, sunny and windy.

Finally, if engineers are able to produce solar panels with 40% efficiency in 40 years [19], why are engineers unable to do the same for photosynthetic efficiency? Why didn't engineers improve photosynthesis efficiency to 40%? If photosynthesis is so poor, wouldn't it be easy to improve? Be assured: scientists are trying very hard! And the stakes are high. I will elaborate on this later.

 

The difference between solar panels and photosynthesis

As we have seen, in only one sense solar panels can be compared with photosynthesis, but in all other respects the comparison breaks down. By simply looking at the formula of photo-synthesis we see that it is a chemical synthesis:

Photosynthesis (wikipedia)

Photo-synthesis is a chemical synthesis of sugar with input carbon-dioxide, water and light. Solar panels fail in all these respects:

  • solar panels have zero percent efficiency for sugar production
  • solar panels have zero percent efficiency for water splitting
  • solar panels have zero percent efficiency for oxygen production
  • solar panels have zero percent efficiency for energy storage
Solar panels fail completely in these respects simply because solar panels are not designed to produce sugar or oxygen or split water. Solar panels only require light (the only limiting factor) and only produce electricity. Plants store the energy  in chemical bonds (sugar).

Water is often plenty available, but not everywhere on earth. Certainly not in areas such as deserts. Typically, deserts would be great for solar panels, but not for plants precisely because of the lack of water. Water can be a limiting factor. And if water is available it has to be transported to the leaves. This definitively shows the difference between solar panels and plants. Further, water uptake requires roots. Roots have to be grown.

CO2 is –despite climate warming– present in very low concentrations in the atmosphere: 415 parts per million, that is just 0.04% [15]. A plant cannot actively grab CO2 from the air. Animals have active breathing and are only interested in oxygen which is present in the atmosphere in a comfortable concentration of 21%. That is more than 500 times higher than carbon-dioxide! Plants don't have active breathing [3]. CO2 ends up inside plant cells mainly by simple diffusion [4]. That CO2 is really a limiting factor is shown when CO2 is experimentally increased: plant growth is stimulated [5]. So, both the concentration of carbon dioxide and the passive diffusion are limiting factors for the rate of photosynthesis. Natural selection can do a lot, but not increasing atmospheric CO2 concentration!

CO2 concentration
figure 1 (source).

Law of Limiting Factors

The Law of limiting factors states that the rate of a physiological process will be limited by the factor which is in shortest supply. Any change in the level of a limiting factor will affect the rate of reaction. (source). In photosynthesis light, temperature and CO2 are limiting factors alone and in combination. Above we have seen the CO2 effect. Here is the temperature effect:

figure 2 (source).

Here is the combination of CO2 and temperature:

 

figure 3 (source).

Below the effect of light is shown (figure 4).
 


CO2 / O2 balance is crucial for photosynthesis

 
Above the law of the limiting factors there is an evolutionary legacy. Earth history and biochemistry show that the relative levels of oxygen and carbon-dioxide in earth’s atmosphere are important. Plants require a minimum level of carbon-dioxide and at the same time not too much oxygen. This is because the enzyme involved in photosynthesis (rubisco) doesn't work when carbon-dioxide levels are below 40-65ppm at 21% oxygen level. At 1000ppm carbon-dioxide photosynthesis works very efficiently. At the same time at 2-5% oxygen photosynthesis works well, while at the current level of 21% oxygen there is 25% inhibition of photosynthesis. The oxygen/carbon-dioxide balance has changed during the lifetime of the planet and that has its effect on photosynthesis. The core photosynthesis enzyme rubisco has been adapted to the past [21]. Apparently evolution did not improve this.
 

Too much sunlight!

Steven Vogel (quoted above) already noted that too much sunlight is bad for plants. Direct full sunlight is needlessly bright. He measured leaf temperature on a hot day: 55°C (130°F)! That is clearly outside the range photosynthesis works best: 20° – 35° C (68° – 95°F). Plants manage to survive those harsh conditions. Why aren't they dead?

figure 4 (source).

Rates of photosynthesis in bright sunlight sometimes exceed the needs of the plants, resulting in the formation of excess sugars and starch. When this happens, the regulatory mechanisms of the plant slow down the process of photosynthesis, allowing more absorbed sunlight to go unused [14].

Although light is required for photosynthesis, too much light can be harmful. To protect the photosynthetic apparatus from oxidative damage, photosynthetic systems possess antioxidant systems that scavenge reactive oxygen species, as well as mechanisms that regulate photosynthesis to minimize their production [20].

At high light the absorption of light energy exceeds a plant's capacity for CO2 fixation [20].

Carotenoids are part of a cycle that renders excess energy beyond the level of light saturation harmless, effectively serving as “lightning rods” in the process [14].

These effects explain why photosynthesis rate has a ceiling.


Plants in natural conditions

“People often think that nature is very efficient. It is, but only in natural conditions. The crops we grow were not born for agriculture; we took them from the forests and placed them in fields. If they had completely adapted to these new conditions they would perform much better." ( wur.nl )

According to photosynthesis researcher Vincent P. Gutschick the components of photosynthesis in wild plants have been nearly optimized by natural selection [10]. That explains why breeding for photosynthesis has enabled few discrete gains in yield. Breeding for higher yield has trade-offs such as lower water-use efficiency.

The authors of an article in Science conclude: "the main evolutionary pressure on photosynthetic organisms is that they survive, not that they have the optimum thermodynamic efficiency!" [17]. Very important.

Recently, researchers claim to have eliminated 3 bottlenecks in photosynthesis in tobacco, thereby increasing yield significantly. They are trying to apply the findings to food crops as cassava, cowpea, maize, soybean and rice [11]. The question arises: if this is good for the plant species, why has natural selection not removed these bottlenecks? The answer can only be found when we find out what the evolutionary reasons are. One example is a wasteful process called photorespiration. It's long been thought that more than 30% of the energy produced during photosynthesis is wasted in the process. Now, a new study suggests that photorespiration wastes little energy and instead enhances nitrate assimilation. The researchers propose that something else is going on that shows plants aren't so stupid [9]. Again, digging deeper is rewarding.


Evolution and adaptation

A leaf is not a simple 'solar panel'. A leaf has many functions: "Assuring access to light, providing mechanical support, coping with heat, deploying from a bud, dealing with wind, getting atmospheric carbon dioxide into the cells, extracting water from soil and raising it upward, deterring herbivores" [22].

Pinus
All these functions often require compromises. Furthermore, evolution designed different life-cycle strategies: annual, biennial, perennial. Each of these lifestyles imply different compromises such as fast or slow growing, making many small leaves or few big leaves, producing seed once in the growing season, or every year; deciduous trees (shed leaves in the autumn), conifers (evergreen). For example, deciduous trees show that trees make choices, they shed their leaves and they don't photosynthesise the whole year. Why? Think about that. Clearly, they don't maximize photosynthesis. Otherwise they wouldn't shed their leaves. Apparently, climatological circumstances make it unprofitable to have leaves the whole year.
Something similar holds for conifers. They have long, thin
'leaves' (needles). That is a very small surface compared to 'normal' leaves. Think about it: why do they do that?

 

Summary of main points

  • In an agricultural context photosynthetic efficiency is meaningful and important because it is all about food production
  • In an evolutionary context photosynthesis efficiency is only one of several factors that contribute to survival and reproductive success.
  • Reporting photosynthesis efficiency is meaningless without a precise description of how it is measured: plant species, wild or domesticated, light spectrum considered (Photosynthetically Active Radiation or all wavelengths), how photon flux is measured, which end-product measured [12], water-use efficiency, CO2 levels, minerals, temperature, which 'losses' are included, in the lab or in the field, duration.
  • Limiting factors are: light, CO2, water,  temperature, nutrients [14]. Evolution cannot improve the physical environment!
  • Whenever a feature of a plant in nature looks wasteful and inefficient, we should study the species to find out why [9].

 

Final thoughts

Is photosynthetic efficiency low? First, use your common sense. Whatever the efficiency, it is a fact that plants are able to grow, survive and multiply. That is a remarkable fact. Photosynthesis has existed for some 3.5 billion years. Plants are the evolutionary success story. They made the earth habitable for animals including humans. Plants produce oxygen. Without atmospheric oxygen animals would not exist on earth [24]. The earth is the only known planet with life. Apparently photosynthesis is powerful enough for the existence of 8 million species on earth [23]. We should not ignore the obvious.

Is photosynthetic efficiency low? It is really too simplistic to conclude that 0.1% is low just because the percentage is low. Period. In this blog I introduced the chemical formula of photosynthesis. Many things follow from that formula. Important: carbon-dioxide. To know what the effect of carbon-dioxide is, one has to know what the history of carbon-dioxide and relative CO2/O2 concentrations were in the history of the earth. Those concentrations formed the selection pressures of the core enzyme rubisco. Further, one has to know what the biochemical sensitivity of rubisco is for different concentrations in order to understand the current efficiency of that molecule. Finally, one has to find out if there exists selection pressure at all for higher efficiency of photosynthesis in the wild. That's why it is wrong to say that "0,1% is an extremely poor efficiency for a photosynthetic system that has had the opportunity to evolve for at least 3,500 million year".

Is photosynthetic efficiency low? A better question would be: how are plants adapted to their natural environment? Plants are not adapted to human needs. From an evolutionary point of view agriculture is unnatural. Wild plants have been taken from their natural environment and transported to a different continent with a different climate. Plants are modified in order to redirect their resources to human goals. We want different parts of the plant: the root, stem, leaves, seeds, fruits, and modify plants accordingly. Plants did not evolve to meet human needs.

 

Acknowledgments

I would like to thank Kasper van Gelderen en Thijs Pons.


Notes

  1. Steven Vogel The Life of a Leaf. A second quote about leaves: "These relatively inefficient solar panels provide all the energy a tree can invest in growth, reproduction, and dispersal - the three central concerns of every organism that has ever lived." (505/506)
  2. Karo Michaelian (2016) Thermodynamic Dissipation Theory of the Origin and Evolution of Life, p.312) paperback (see a previous blog). Karo is right about one thing: "Photosynthesis was well-established on the earth at least 3.5 thousand million years ago." (source). In a next blog I will refute Dissipation theory with evolutionary biology.
  3. CO2 is not always passively transported. C4 plants use a biochemical pump to concentrate CO2 at the locations within the leaf where the RUBISCO enzyme mediates incorporation of CO2.
  4. Andrew Bocarsly of Princeton University: "We've been studying CO2 chemistry for a long time, more than 100 years, and there's very little evidence that we could do what a leaf does."
  5. Effects of Carbon Dioxide on Photosynthesis, Plant Growth, and Other Processes
  6. see wikipedia article Measuring ancient-Earth carbon dioxide concentration.
  7. Energy efficiency of photosynthesis, Britannica (free article)
  8. The theoretical maximum efficiency of solar energy conversion is approximately 11% (wikipedia).
  9. Shedding light on the energy-efficiency of photosynthesisSciencedaily, 2018. "a new study suggests that photorespiration wastes little energy and instead enhances nitrate assimilation,".
  10. Vincent P. Gutschick (1997) Photosynthesis, Growth Rate, and Biomass Allocation, Ecology in Agriculture, 1997 
  11. Third breakthrough demonstrates photosynthetic hacks can boost yield, conserve water. August 10, 2020
  12. End-product: "Only 5% of the sunlight that hits this field ends up in these grains"! (Dr Matt Johnson). "if only agricultural products (e.g., seeds, fruits, and tubers, rather than total biomass) are considered as the end product of the energy-conversion process of photosynthesis, the efficiency falls even further." (source)
  13. C4 plants: "The C4 metabolic pathway is a valuable recent evolutionary innovation in plants, involving a complex set of adaptive changes to physiology and gene expression patterns." (wikipedia).
  14. Britannica. "Several minerals are required for healthy plant growth and for maximum rates of photosynthesis. Nitrogen, sulfate, phosphate, iron, magnesium, calcium, and potassium are required in substantial amounts".
  15. Industrial carbon capture from the air is costly because CO2 has a low concentration in the air and lots of water are required! Just like photosynthesis!
  16. The Average Photovoltaic System Efficiency, Sciencing, April 25, 2017
  17. quoted in this blog Is photosynthesis highly efficient? 2012
  18. Comparing Photosynthetic and Photovoltaic Efficiencies and Recognizing the Potential for Improvement, Science,  13 May 2011. (a pdf can be downloaded here)
  19. On page 223 of his book he writes "in only 25 years" for the solar panels and "after more than 3.8 Ga years of biological evolution" for photosynthesis, making the difference still bigger! Exaggeration!
  20. Photosynthesis, R.C. Leegood, in Encyclopedia of Biological Chemistry (Second Edition), 2013.
  21. Evolution on Planet Earth, page 21.
  22. Steven Vogel The Life of a Leaf., 28/990 (ebook)
  23. How many species on Earth? About 8.7 million, new estimate says. Science daily 2011.
  24. "Animals depend on oxygen because they need it to release energy from sugars, fats and proteins. In strict chemical terms, cellular respiration reverses the reaction at the core of photosynthesis. Sugar and oxygen react with each other to make water and carbon dioxide, releasing a lot of energy." Paul Nurse (2020) What is Life? 22 Nov 2020
  25. Nobel prize winner Paul Nurse (2020): "If we could re-engineer plants to carry out photosynthesis even more efficiently than they do..." in: What is Life? 306/360 24 Nov 2020
  26. Do Solar Panels Work Less Efficiently at Certain Temperatures? Added: 24 Jul 2022. Nederlands: "Zonnepanelen werken het meest efficiënt bij een lage temperatuur. Voor iedere 10 graden temperatuurstijging daalt de stroomopbrengst tot 5%. De reden? Zonnepanelen geleiden de stroom beter bij kou dan bij warmte. Bij 10 graden met een zonnetje wekken zonnepanelen tot 10% meer stroom op dan bij een vergelijkbare zonnige dag met een temperatuur van 30 graden.". bron: Opbrengst zonnepanelen: wat is de invloed van het weer? (toegevoegd: 24 Jul 2022)


Previous blogs about photosynthesis


16 comments:

  1. Sorry, but not at all convincing Gert. When referring to my book please always quote me in full to avoid misleading your audience as to what my message actually was.

    On page 307 of my book "Thermodynamic Dissipation Theory of the Origin and Evolution of Life" I write "Only approximately 0.1% of the free energy in sunlight captured by the leaves of a plant is used in the fixation of carbon through the process of photosynthesis (Gates, 1980). Experiments performed in the 1930's had shown that under intense light conditions, for every chlorophyll molecule that absorbed a photon and participated in the photosynthetic process, there were about 300 other chlorophylls in the plant that simply dissipated their photon excitation energy directly into heat (Mohr and Schopfer, 2015). 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."

    You can look up solar cell efficiencies in Wikipedia and you will find the following "In 2019, the world record for solar cell efficiency at 47.1% was achieved by using multi-junction concentrator solar cells, developed at National Renewable Energy Laboratory, Golden, Colorado, USA.[5] This is above the standard rating of 37.0% for polycrystalline photovoltaic or thin-film solar cells.[6]". Our maximum efficiencies for solar cells keep improving every year.

    Efficiency of energy conversion is measured by free energy absorbed of one type to free energy available after being converted to another type. For photosynthesis the converted type is chemical potential (energy stored in covalent bonding) and for solar cells it is electrical potential.

    Every conversion process of course has its losses. Of course nothing can ever be 100% efficient. Photosynthesis has its energy conversion losses at 99.9%, our best solar cells presently have energy conversion losses of 53%. Is that because Nature acting through natural selection is a poor optimizer of energy conversion efficiency? No, I never suggested that. What I suggest is that Nature does not have as it's "goal" optimizing photosynthesis. It's main "goal" (or reason for existence) is optimizing photon dissipation, and it does that extremely efficiently.

    Saying that photosynthesis as it is now set up by Nature has its inherent conversion efficiency limits does not say anything and certainly does not get you off the hook. The question is "If the "goal" of Nature was to optimize photosynthesis (plant growth) why then has it come up with such an inefficient system?"

    By the way, engineers are, in fact, improving the efficiency of photosynthesis. There are many groups working on this. Here is just one example; https://pubag.nal.usda.gov/download/50605/PDF

    You conclude by saying "Finally, one has to find out if there exists selection pressure at all for higher efficiency of photosynthesis in the wild." Exactly, now you are getting close to what I am saying. I am saying, "No, there is evidence that photosynthesis is necessary, but there is no evidence that Nature is concerned about optimizing photosynthesis." But, the more important question you should be asking is "Does there exist selection pressure at all for higher efficiency of photon dissipation in the wild?". I am saying "Definitely a resounding YES, there does exist a lot of evidence for this". The evidence is listed in my book, my book is all about that.

    I would suggest that your readers get a copy of my book for free by looking up my name on Google "ResearchGate" and downloading it and reading it for themselves, since your caricature of it has always been very unfair.

    ReplyDelete
  2. An important question to ask is "Exactly what is natural selection selecting?". In your blog you say that it is selecting "survival" and thus you seem to have an excuse as to why photosynthetic efficiency is so low, presumably because it is not being strongly selected on (the latter part I agree with). However, we know that this is not the case, otherwise there would not exist programmed death, for example. The neo-Darwinists would say that "differential reproductive success" is what is being selected. However, we know that this is also not true since we never see one species completely dominating all others. The most stable and climax ecosystems are those with the most species diversity.

    The thermodynamic dissipation theory has a more reasonable answer. On page 286 of my book, I write " Like any irreversible process, life at whatever level necessarily "feeds" off an external generalized chemical potential produced at a higher level of dissipation (When speaking about "levels" in this thermodynamic sense, there is no casual relationship assumed with the levels of the conventional ecological pyramid. At the highest thermodynamic level is the dissipation of solar photons into heat by pigments in water and the production of chemical potential in the covalent structuring of organic elements. These latter two give rise to the water cycle and herbivores respectively in the dissipative chain, and so on until the free energy content becomes minimal and energy of high entropy is emitted into space. Feedback between the different thermodynamic levels (for example, the water cycle fomenting the greening of the planet and thus photon dissipation) is the source of selection on various simultaneous levels.)
    This external potential defines, to a large extent, the external environment of a living organism. More accurately stated, life develops as a spontaneous organization of material in response to an applied external potential coming from its environment. Under this thermodynamic view based on physical and chemical law, life is not acting out of self-interest with a view to survival, but rather is a dissipative flow that waxes and wanes in response to the local forces of the local external environmental, those forces that are driving it to becoming. persisting and proliferating.

    Within this environment, however, there are other physical factors, for example, temperature, which affect the ability of the material to organize into dissipative structures. If the external potential or these other physical factors change, for whatever external or internal reason (e.g. through feedback mechanisms), life may "adapt" (The word "adapt" in this thermodynamic sense means any change of the system+environment which increases the overall dissipation rate.
    ), through its inherent plasticity, and continue dissipating the potential in the new, perturbed environment. During this process of "adaption", individuals may die or species go extinct or morph gradually into others. It is the imposed external potential that "selects" the individual or species, but this should not be looked at as an organismal struggle against its environment for survival, but more as an adaption of the dissipating process to the new constraints of the environment, such that the system as a whole, environment plus organism, can continue dissipating the solar photon potential. Survival, non-survival, and morphing are all adaptive responses in this thermodynamic view."

    ReplyDelete
  3. Dear Karo,
    before replying your comment, these observations first:

    - you are as a physicist writing about biological matters, not just about small matters, but making really revolutionary claims,
    - you don't display profound biological knowledge nor asked me, a biologist, for advice or information,
    - when I was preparing my post about photosynthesis I asked advice from photosynthesis specialists because I am a biologist but not a photosynthesis expert myself. Scientists trust each other and ask advice because that prevents embarrassing errors and wasting time on a stupid idea
    - neither are you an evolutionary biologist or show any knowledge of it. On my website I display 40 evolutionary biology textbooks aimed at students. These contain obligatory basic matter only.
    - in this post I dig deeper into photosynthesis not only for my own desire for better understanding, but also to help you with your research in unfamiliar territory.
    - while I am helping you, you reject out of hand or ignore nearly the whole post
    - above that you seem to cast doubt on my integrity and honesty! smart move! thanks! that is good for creating personal friendship and scientific cooperation!
    - you are trying to refute evolutionary biology in a naive and silly way apparently in order to defend your theory and promote your book at all costs.
    - if you want to add a hypothesis or fact to biology, or propose a solution to a long-standing, unanswered question in biology, it is mandatory to posses the same level of understanding as biologists about the current status of knowledge in the (sub)discipline.


    These are general observations about your behaviour so far.

    ReplyDelete
  4. Dear Gert,

    It is not a good idea to make our discussions personal. I simply asked that if you are going to quote me, then please quote me in full. Do not "interpret me" and then include only half of my quote without references, as though it supports your interpretation of me. I think that such a request is nothing at all out of the ordinary and is just ethically the correct thing to do and shows common decency. You should not get upset about such a request, and its not the first time I made this same request to you.

    You are not being scientific, and indeed, simply very rude, when you use words like "stupid", "naive", "silly", "embarrassing" when referring to my work. I am not interested in your personal "observations about my personality" or about my work. I gave you my scientific review of your blog because you specifically asked me to do it. It was a scientific review and if you have disagreements or concerns, then please, by all means address yourself to the scientific issues, there is no place for criticism of perceived personalities in science.

    I am not concerned with promoting my book (there is no money in it for me and it has already been extensively downloaded) but I will defend the theory against frivolous attacks based largely on misunderstandings and misinterpretations. In fact, that is what I assumed you wanted me to do when you asked me to comment on this particular blog.

    Evolution is not something only existent within the domain of biology. Evolution occurs in many systems that one would not say were alive. The word "entropy" which comes from physics, in fact, is the Greek word for evolution. Don't assume that only biologists are somehow the experts or owners of evolutionary theory or that only they can say something intelligent on the issues. As much as you cherish the traditional Darwinian theory, there are many problems and paradoxes associated with it, and this is not only me saying this, but some very respected biologists/paleontologists like S.J. Gould. Is his book "The Structure of Evolutionary Theory" on your list? If not, I suggest that you read it, particularly his chapters about the problems in evolutionary theory, and then tell me with all honesty that you and I are not on the same level of understanding.

    ReplyDelete
  5. dear Karo

    1. ad hominem is the default argument of darwinists (defines darwinists)

    2. thanks for your explanation

    3. I agree that evolution is 'not something only existent within the domain of evolution'.

    Indeed, following Boltzmann it is even non-existent in that domain. ( see: L. Boltzmann, Der zweite Hauptsatz der mechanischen Wärmetheorie (Vortrag, gehalten in der feierlichen Sitzung der Kaiserlichen Akademie der Wissenschaften am 29. Mai 1886.)

    ReplyDelete
    Replies
    1. Thanks for your remarks and the Boltzmann reference! It´s not easy to find them translated into English.

      Delete
  6. sorry, correction:
    domain of evolution= domain of biology

    ReplyDelete

  7. "we have a motto and we stick to it:.. when things get hard to believe... we believe harder".

    https://whyevolutionistrue.com/2020/11/11/jesus-n-mo-n-obstinacy/

    ReplyDelete
  8. Karo wrote: "It is not a good idea to make our discussions personal." Right!
    Karo, you started your first comment politely with: "When referring to my book please always quote me in full to avoid misleading your audience as to what my message actually was. "
    although the word 'misleading' is somewhat aggressive because implies that I want for some reason mislead my readers!!!
    BUT at the end of your comment all politeness is gone:
    "...since your caricature of it has always been very unfair."
    that are 3 insults. Is that scientific language? Does that display trust in me? you started with distrust.
    'caricature'? is that scientific? are you implying that I do it on purpose? could there be an innocent reason? a good reason? Could it be there are misunderstandings in the communication between a physicist and a biologist? etc. You started with very strong emotional words.
    Always? Are you implying I always make a caricature of you and your theory? Always means no exceptions! I never quoted you correctly? I always misrepresented your theory? I misquoted you hundreds of times on a daily basis? Maybe in reality it happened IN YOUR EYES twice, using the word 'always' is not only false, but it means I must be a really bad person! 'Always' is a very dangerous word!

    Karo: "Is his book "The Structure of Evolutionary Theory" on your list?"
    http://wasdarwinwrong.com/korthof63.htm (28 May 2004)
    Karo, what is your favourite evolution handbook? which one do you have at home or at work? Or did you bypass an evolution textbook and went straight to the critics? You don't trust mainstream science and only trusts the critics?
    All this reminds me of creationists who never do the effort to study textbooks of evolution but go straight to criticism. This is the wrong order. FIRST have complete knowledge of what the theory of evolution is before trying some critics.

    Please note I did not yet reply to your scientific comments, because we must first get rid of the personal, and emotional attacks on each other.

    ReplyDelete
  9. Harry! Je leeft nog! Goed een levensteken te krijgen in deze coronatijden! Wij behoren tot de risicogroep schijnt het... Meesterlijk uitspraak heb je daar! Geweldig!

    ReplyDelete
  10. Karo, your comment at Monday, November 9, 2020 at 9:03:00 PM GMT+1:

    1) Karo said: "Sorry, but not at all convincing Gert. "
    "convincing" is a subjective concept, it has no meaning if it is not backup by arguments and facts of everything I wrote. Not cherry-picking!

    2) Karo wrote: "You can look up solar cell efficiencies in Wikipedia and you will find the following..."
    I explained at length in my blog why solar panels are unlike photosynthesis so this quote is pointless.

    2) you seem to admit hesitantly and indirectly that there is a difference: "For photosynthesis the converted type is chemical potential (energy stored in covalent bonding) and for solar cells it is electrical potential."
    but I explained the difference much better.

    3) Karo: "...Photosynthesis has its energy conversion losses at 99.9%, our best solar cells presently have energy conversion losses of 53%. ..."
    Again false comparison! You ignore my arguments in the blog. Unscientific!

    4a) Karo "What I suggest is that Nature does not have as it's "goal" optimizing photosynthesis. It's main "goal" (or reason for existence) is optimizing photon dissipation, and it does that extremely efficiently."
    The goals of plants is survive (out)compete, (out)reproduce. Photosynthesis is part of that goal.

    b) Karo: "It's main "goal" (or reason for existence) is optimizing photon dissipation, and it does that extremely efficiently."
    Again: I already pointed out that 99,9% is misleading.
    The statement itself: how did you establish optimizing photon dissipation? how did you calculate the optimum? Do you have a calculation that results in 99,9%? Or you you just copy the number from the literature and exclaim AHA! THERE YOU HAVE IT!
    Explain why it is not maximized. You don't have a quantitative theory based on dissipation theory. You don't have a theory at all to calculate anything.

    c) Karo: ".... and it does that extremely efficiently."
    From your point of view the plant is extremely energy efficient because it uses only 0,1% of the incoming energy for ITSELF, and the rest for dissipation. In other words: with the 0,1% of solar energy it can grow, make leaves, do photosynthesis, defend itself, and reproduce. That is extremely efficient from you point of view!
    The whole dissipation theory is self-defeating: 1) the plant must survive in order to dissipate, so survival is primary and dissipation is secondary. 2) the plant must reproduce to cover the earth, so reproduction is primary and dissipation is secondary and a side-effect.

    5) Karo: " "If the "goal" of Nature was to optimize photosynthesis (plant growth) why then has it come up with such an inefficient system?"
    Wrong: Photosynthesis is not the same as plant growth. I explained in my blog. You make several errors in one sentence.
    (one example: photosynthesis depends CO2 in atmosphere. etc. You ignore this. etc.)

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  11. 6) Karo: "By the way, engineers are, in fact, improving the efficiency of photosynthesis"
    Just as they do with milk production in cows over the last 50 years! So what? It is agriculture! it is unnatural. It is artificial evolution not natural evolution. It is no proof of your theory.
    WRONG. I wrote in my blog: "Finally, if engineers are able to produce solar panels with 40% efficiency in 40 years [19], why are engineers unable to do the same for photosynthetic efficiency? Why didn't engineers improve photosynthesis efficiency to 40%? If photosynthesis is so poor, wouldn't it be easy to improve? Be assured: scientists are trying very hard! And the stakes are high."
    You ignored this!!!

    7) Karo: "No, there is evidence that photosynthesis is necessary [THANKS!], but there is no evidence that Nature is concerned about optimizing photosynthesis.""
    I explained in my blog that photosynthesis is embedded in other processes. Read the blog again, but now carefully.
    You ignored the theoretical limit of efficiency. WRONG! Ignoring most facts is not scientific!
    see 4c) you have no theory to calculate anything about photosynthesis and dissipation. In previous blogs I pointed out that your theory is unfalsifiable: every efficiency value seems to be compatible with your 'theory'. What would you decide if photosynthesis would be 40% efficient??? Would THAT refute your theory???
    I stop here for a cup of tea :-)

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  12. Gert, if you insist I can give you a rebuttal on each and everyone of your points above, but after a while it becomes tiring and my answers seem to have little utility to you. We are simply analyzing on different levels. I understand that it is really difficult for most biologists to go one level deeper to understand the physics and chemistry of living systems. However, it is not impossible. There is at least one professional biologist who, after reviewing all the theories on the origin of life, reached out to me 10 years ago to tell me that mine was the only one that made any sense to him and that he would like to collaborate with me. From that time on we have been collaborating and publishing together (his name is Aleksander Simeonov, maybe you would like to read our articles we have together which you can download from my ResearchGate). I also give a class on the Thermodynamic Dissipation Theory to Bachelors students and I get many young biology students signing up for my class, and, not all, but a lot of them do arrive at a good understanding of the theory and are intrigued by it. Many of them also realize that there are many paradoxes, inconsistencies and problems with Darwinian theory (for example, there is no getting at the origin of life from within the Darwinian framework and that should ring alarm bells for you) and so have been looking themselves for a deeper understanding.

    I think that you are also searching for something deeper but don't know how to go about it without feeling like a traitor. It is a great source of satisfaction to me to learn that my theory is not out of the reach of understanding of biologists and partly for that I decided to write by book which is a gentle introduction to the theory for the non-physicist. I now realize that I have to redact an even simpler version of my theory for those who have had no physics or chemistry and find it difficult to understand concepts such as free energy, entropy, thermodynamic efficiency (as I see you are struggling with from your replies above). Although we have published a very simple version of the dissipative theory in Spanish, I am now working on an improved English version and I hope to have that available in a few weeks so please be patient.

    I have given many ways that the Thermodynamic Dissipation theory for the origin and evolution of life could be potentially falsified. One very related to this blog is; If there is anything that you can find besides photon dissipation that Nature optimizes (e.g. photosynthesis, survival, population, reproduction, free energy utilization, biomass, etc.) then you would have falsified my theory. Very simple, but careful, living things do not exist in a vacuum, they are always interacting with other organisms and with the abiotic environment. You have to show me that Nature is optimizing these other things for the whole ecosystem or biosphere, not for its parts in some kind of hypothetical isolationism. Most of the paradoxes in Darwinian theory arise when biologists forget about the interactions and treat individuals as autonomous actors.

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  13. Karo wrote: "Gert, if you insist I can give you a rebuttal on each and everyone of your points above, but after a while it becomes tiring and my answers seem to have little utility to you.

    Little utility??? I read your comments, I think about them, I answer them!!! I don't know if you read my replies, but certainly you did not answer them!
    Insist??? that is really strange: is the point of a scientific discussion not replying? Now, I am the bad boy who strangely 'insists' on a reply :-( I don't want to 'insist', I assumed a scientific discussion consists of comments and replies... and replies ...
    Readers can easily interpret your silence as not having answers or not interested in biology.

    I read your comment, but I am afraid in the end you are not interested in plants, animals, photosynthesis, evolution at all. You don't really care about it! You don't need to be interested in biologists, but you do need the be interested in living things. You have been dismissive about biologists in previous discussions on this blog (biologists are too stupid to understand mathematics) and you are not interested in the circumstances under which plants perform photosynthesis. You simply (largely) ignored what I wrote in this blog about photosynthesis. You only want to apply your theory and don't care about the subject otherwise. You don't want to know how organisms really work. You have your own theory already in place. One should have a deep interest in the subject one is studying. Biologists want to know how organisms really work. Otherwise you will not discover anything new, you will not make any progress.
    Your way out: ignoring what a biologist wrote, and not answering.

    Karo: "living things do not exist in a vacuum, they are always interacting with other organisms and with the abiotic environment. "
    Abiotic environment??? That is a joke! I precisely wrote about the abiotic context of photosynthesis in the above blog! and you ignored all of it!

    Karo: "I also give a class on the Thermodynamic Dissipation Theory..".
    Do you also give lectures about photosynthesis to biology students?
    Evolutionary biology lectures? Are there evolutionary biologists in your building you could talk to?

    ReplyDelete
  14. KARO wrote "(as I see you are struggling with from your replies above"
    I can clearly see that you are struggling with biological and evolutionary concepts and thinking in your book. You fight against a caricature of biology en evolution you have created yourself.
    What is the problem with your book is that you don't really investigate how to apply a well established physical theory to a foreign territory for which it was not developed.
    You have really to do a lot of work before you can apply the thermodynamic theory to biology. You did not even start to apply it to concrete examples in biology. If the dissipation is so all important start with applying it to the colors of birds and animals in general: why black birds? why white? why all the other colors? Apply it to the existence of warm and cold blooded animals, etc etc. Be specific. Make predictions. etc.
    This is all to help you!

    ReplyDelete
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