https://www.the-scientist.com/news-opinion/weak-magnetic-fields-manipulate-regeneration...

"Exposure to weak magnetic fields can, depending on their strength, either slow or boost flatworm regeneration, according to a report in Science Advances today (January 30). The study provides evidence for a possible mechanism, showing that magnetic fields affect the production of reactive oxygen species, which in turn alter cell behavior.

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"A major hypothesis for the biological effect of weak magnetic fields (those between Earth’s average and 1 mT) is that they might induce a process called radical pair recombination. In essence, it is thought that a magnetic field might alter the spin direction of electrons in the outer shells of atoms, disturbing the molecular pairing of such atoms and favoring free radical formation. In the case of certain molecules containing oxygen, for example, this disturbance would increase the production of reactive oxygen species (ROS).

"With this possible mechanism in mind, Beane and colleagues examined magnetic field effects on a biological system known to require ROS—regeneration in the planarian flatworm Schmidtea mediterranea.

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"They found that magnetic fields between 100 and 400 µT inhibited the growth of blastemas compared to those developed by worm fragments exposed to Earth-equivalent fields (45 µT), and that a 500 µT magnetic field increased blastema growth. The differences in growth seen at 200 µT (the strength at which peak inhibition was observed) and 500 µT were associated with differences in ROS levels, which were lower than normal in the 200 µT–exposed animals and higher than normal in the 500 µT–exposed animals.

"Why these unexpected and different effects on ROS levels are seen at different field strengths is not clear. One possibility, explains Ben Greenebaum, an emeritus physicist at the University of Wisconsin who was not part of the research team, is that while a certain amount of magnetic energy can flip the spin direction of electrons, other energy levels can “flip it back,” meaning nonlinear outcomes may be observed.

"The reduced blastema growth seen in 200 µT–exposed worms was also associated with reduced stem cell proliferation and lower levels of a ROS-induced stress protein. Moreover, artificially boosting ROS levels in 200 µT–exposed animals rescued blastema growth, providing evidence that ROS are indeed mediators of magnetic field effects, albeit not exactly as predicted by the radical pair recombination hypothesis.

Comment: another physical influence on cellular processes

dhw:You agree that both offer a rational explanation of the higgledy-piggledy bush of animal evolution, as opposed to your following statement under ”The biochemistry of cell adhesion...”:
> 
> David: “I have previously said I have no idea how/why God did this in the way He did. I firmly think He directed and managed the process and progress of evolution.”
> 
> dhw: But you can find no flaw in the two theistic hypotheses I have offered. So maybe now we do have an idea how/why God did this in the way He did it.-You may propose, but you go much further than I do. I can honestly agree your theistic theories are possible, but I think not probable. I chose not to look for the reasons you come up with. We have no idea how God did what he did.-> DAVID: What other approach can we use? I don't trust religions' opinions.
> 
> dhw: There are experiences that take us beyond the current reach of science and reason: psychic, emotional, aesthetic, mystic...These have not led me personally to God, but they are strong enough to have led others in that direction, and I do not have faith that eventually they will be explained by atheistic materialism.-Amen!

DAVID: You can conjure up all the possible God thoughts you wish. Humans are here as the pinnacle of evolution.
> 
> dhw: My focus in this discussion is on how evolution works. I repeated your own question (why so many phyla?) and also asked what was the point of all those that died out. I have offered two possible answers allowing for your theistic, anthropocentric version of evolution. Can you see any flaw in these two explanations for what you have agreed is the helter-skelter bush of animal evolution?-Actually, no. But you used a mechanism of imagining God's thoughts to make your point, which is why I answered the way I did.
 
> dhw: Yes, indeed. And one needs faith to fill in the huge gaps in both arguments, since neither science nor reason can do so. I should add, however, that science and reason may not be the best guides to “truth”, whatever that may be.-What other approach can we use? I don't trust religions' opinions.


> dhw:Still wearing my theist hat, I ask the same question. Why so many, and what was the point of all those that died out? You have now acknowledged the possibility that your God had to experiment in order to get to humans. Two explanations: 1) the explosion of phyla was not in aid of humans at all: they worked out their own evolution. Humans were an afterthought. 2) He wanted to create humans, didn't have a clue how to do it, and blundered through all those species which he then had to discard.-You can conjure up all the possible God thoughts you wish. Humans are here as the pinnacle of evolution
> 
> dhw: These discussions are invaluable to me, though. The vast range of your own knowledge, coupled with that of BBella, Tony, Matt, George and many others down through the years, has immeasurably deepened my own awareness of the mysteries of life and the universe, even if I am as far as ever from solving them! -Solving with absolute proof is impossible.-> dhw: Romansh has hit the nail on the head in his post under “Golden Ratio”: “I like the analogy of our knowledge being a little bit like cosmic inflation. While our "knowledge" increases in leaps and bounds; our ignorance, the boundary between what we know and don't know also increases.” The perfect summing up.-Yes!


> dhw: “God may have invented the mechanism”: This can hardly be called ignoring the origin of life. The difference between us is your anthropocentric interpretation of evolution versus my free-for-all, driven by an autonomously inventive mechanism, possibly designed by your God and - Hypothesis 3 - allowing for dabbling.-I'll stick to anthropocentrism, thank you. My return to origin of life is to insist upon the presence of information, implanted from the beginning that presents the basis and blueprint for life and evolution. Of course it allows for dabbling, if that had to exist. -> DAVID: Our view still differs. The Cambrian started 37 phyla. This provides for balance of nature, about which you seem to deny the importance of a food source for everyone.
> 
> dhw: Who is “everyone”? The balance of Nature has constantly changed, and no doubt one of the causes/results (it's a vicious circle) of that shifting balance is that there is NOT enough food for “everyone”. How does that mean that the helter-skelter bush, including the 99% of extinct species, was designed to produce or feed humans?-You didn't think about 37 phyla. Why so many? Could humans have arrived if here were less? Actually there were many more that started and died away as you point out. As for balance of nature, sure it has changed through the centuries, but today humans are doing more to destroy it. In the past the changes drove innovation, but as I look at the bush of hominins, I still don't see a change in the balances of nature that required humans to appear. The balance supports us now, but we are in danger of losing it unless we accept the Bible's instruction that we have dominion over it. I'm simply reasoning backward from these considerations. Actually all you do is poke holes, but I like that because it refines my thinking.
> 
> dhw:I am delighted that so many new findings appeared between 12 December and 19 December to enable you to make this adjustment to your assumptions.-I adjust all the time, and you help. It is as if you are the natural selection for my conjectures.

DAVID: Our difference is I assume intelligence is eternal and always existed in/as God. You can't/won't do that. Intelligence CANNOT appear from inorganic matter as life starts, and initial life needs intelligent instructions/information.
> 
> dhw: As usual, you return to the origin of life and intelligence, ignoring the very words you quote: “...your God may have invented the mechanism. The dispute is over how evolution works...”-But I can't ignore the origin of life setting the stage for the evolution of life.
> 
> Dhw: Perhaps you cannot even contemplate this hypothesis because it would undermine your personal reading of your God's mind and purpose. 
> DAVID: I've agreed He can give them the ability to make 'evolutionary decisions', only I add some guideline limits in order to be sure humans arrive. You don't like that limitation. Under your system it should advance helter-skelter and it is possible humans might never arrive. I think the advances of evolution are directed toward us as the definite endpoint.
> 
> dhw: 3). My ”system” does not say evolution “should” advance helter-skelter (or higgledy-piggledy); it is based on the observation that evolution HAS advanced that way, as you finally admit under “Red Deer Cave people”:
> 
> David: “The Cambrian was a shotgun mechanism going off in all directions and produced the helter-skelter bush of animal life.”
> 
> dhw: I could hardly have expressed it better myself. You have consistently claimed all the innovations, lifestyles and wonders were preprogrammed or directly invented by your God for the sake of humans. The “helter-skelter” bush of animal life can hardly be called “guided”, and therefore entails sheer chance (which we both reject) or autonomous, inventive intelligence.-Our view still differs. The Cambrian started 37 phyla. This provides for balance of nature, about which you seem to deny the importance of a food source for everyone.-> 
> DAVID (same post): “This raises a consideration you will accept: perhaps God had an endpoint in humans, but had to develop it through evolutionary experimentation since he is a 'process type' of God, not as totally all-powerful as religions like to represent. ” 
> 
> dhw: Thank you for offering me my own hypothesis 3), which I offered to you in my post of 11 December under “A new synthesis”: “God says: ”I wanner make humans, but I dunno how to do it.” (Special status but the mechanism runs free, and God has a dabble here and there, like when humans turn out to be dinosaurs.)” Your response to this on 12 December was: ”I assume, if God is guiding evolution, He knows everything.” It's good to see that you are now prepared to reconsider your assumptions.-Yes, I can reconsider, with all the hominins turning up. I always reconsider as new findings appear.


> dhw: Nobody knows how any form of intelligence developed, but I am an agnostic, and have repeated a thousand times that your God may have invented the mechanism. The dispute is over how evolution works, and my hypothesis is an alternative to your divine 3.8-billion-year-old computer programme to explain every innovation from the year dot.-Our difference is I assume intelligence is eternal and always existed in/as God. You can't/won't do that. Intelligence CANNOT appear from inorganic matter as life starts, and initial life needs intelligent instructions/information.-> DAVID: I guess you cannot accept God because you are incredulous at what I believe He can do. Is that your hang-up?
> 
> dhw:I am incredulous at the fact that you do not believe your God could invent an autonomous intelligence allowing organisms to make their own evolutionary decisions, rather than him planning every one, though his aim was just to produce humans. Perhaps you cannot even contemplate this hypothesis because it would undermine your personal reading of your God's mind and purpose. -I've agreed He can give them the ability to make 'evolutionary decisions', only I add some guideline limits in order to be sure humans arrive. You don't like that limitation. Under your system it should advance helter-skelter and it is possible humans might never arrive. I think the advances of evolution are directed toward us as the definite endpoint.

We share the concept of a built-in drive for improvement and complexity, but what you call ”God-given information supplied at the origin of life” is what I have suggested is AUTONOMOUS INTELLIGENCE, whereas you have suggested that it is divine preprogramming or personal intervention.-
You have never explained how 'autonomous intelligence' develops, if my memory is correct. As life began from inorganic matter, you want intelligence to arise also?
> 
> DAVID: And what is that superior intelligence you are postulating?
> 
> dhw: The intelligence to reinvent themselves internally (innovations) and to invent externally (weird lifestyles and certain natural wonders) so that they can adapt to or exploit environmental conditions. ...You know all this, because you quite rightly emphasize that such intelligence could hardly be the product of chance, but you refuse to contemplate the possibility that your God might have created it! For you, every single act of cellular intelligence must have been preprogrammed (or personally “guided”) by your God, as in this response:
> 
> DAVID: Simple God programmed in the kind of information/instructions that handle it.
> 
> dhw: A simple 3.8-billion-year-old programme inserted into the first cells to organize the history of evolution from bacteria to humans? Is that really simpler than a single invention that can diversify?-I guess you cannot accept God because you are incredulous at what I believe He can do. Is that your hang-up?


> dhw: And so it is not only changes in the environment that trigger the drive for improvement. Organisms may even improve within the same environment. The bacteria are still bacteria, so we can't talk of innovation here, but the key words for me are “improve” and “exploit”. It's the same process as with the jellyfish and all other innovations, lifestyles and natural wonders: the drive for improvement and the exploitation of conditions. And it starts at the level of single cells. 
> 
> Once again, my thanks not only for these articles but also for the intellectual integrity with which you have posted them, since you knew I would use them to support my own hypothesis.-Thank you. There is obviously a drive for improvement and complexity. It is built-in. I've thought so all along during my research. I view it as another form of God-given information supplied at the origin of life.