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> "I realized that electric eels in the Amazon River could well act as a power source, organisms living in the surrounding area could act as recipient cells, an

> "I realized that electric eels in the Amazon River could well act as a power source, organisms living in the surrounding area could act as recipient cells, and environmental DNA fragments released into the water would become foreign genes, causing genetic recombination in the surrounding organisms because of electric discharge.” So if I'm reading this correctly, and Atsuo Lida is correct, then lightning zapping a water source which is teaming with life can trigger genetic recombination[0], and by extension, possibly catalyse evolution (at least sometimes)? I do love the idea, and am aware that I have no idea what I'm talking about here. [0] https://www.palomar.edu/anthro/synthetic/synth_7.htm#:~:text=Subsequently%2C%20recombination%20by%20itself%20does,nature%20selects%20for%20or%20against https://www.palomar.edu/anthro/synthetic/synth_7.htm#:~:text....

tomohelix 3y ago
Yes! Electroporation is literally just subjecting the cells to a strong electrical potential. A lightning can definitely do the trick in some conditions. Many cells will die, but it is a sacrifice natural selection is willing to make. Although, this doesn't mean you zapping someone with enough lightning and they can become the flash. The electroporation process is one way of damaging the cell just enough to make them take in foreign DNA. Think of it like poking holes in the cell and DNA got in. Whether that DNA get recombined or not depends on other processes, which might also get activated as a stress response to the damage. But it is entirely random. So the DNA coding that specific function/protein must be available in the environment first, and the cell must survive the process of getting struck by Zeus and be lucky enough to do the recombination just right to retain that piece of DNA to produce a proper mutant. Lots of entropy here, like someone said elsewhere. But that is life. Do it enough time and maybe something fun come out of it.
- karim79 3y ago
  So then, I suppose, the 'lethal zone' would be heavily dependant on the power of the lightning strike, the volume of the available body of water, the density of life within the water, and probably thousands of other factors. It would perhaps be much worse for ocean-dwellers than for fresh-water life due to the conductivity differences. I would love to see a computer simulation of this, e.g., for each type of aquatic ecosystem, what would be the recombination sweet-spot or optimal conditions for genetic recombination within a lightning-affected area.
- gumby 3y ago
  > A lightning can definitely do the trick in some conditions. Many cells will die, but it is a sacrifice natural selection is willing to make. While I agree with Dennett,* I don’t think agency is correctly ascribed here, unless you can find selection for locations of increased lightning incidence(!). It’s more like “any survivors remain subject to natural selection, as did those unfortunates that did not survive” * https://en.wikipedia.org/wiki/Intentional_stance https://en.wikipedia.org/wiki/Intentional_stance
  - cariaso 3y ago
    It's more than natural selection. https://en.wikipedia.org/wiki/Electroporation https://en.wikipedia.org/wiki/Electroporation enables gene transfer.
    - gumby 3y ago
      Yes, that was the topic of the article. I am just dubious that a location that got a lot of lightning could be selected for, though lightning is not uniform across the globe. But it's a rather crude factor and hard to defend against on a micro scale!
      - jacquesm 3y ago
        In the past there were periods of billions of years at a stretch with not much else going on that single celled organisms being zapped by lightning. You'd think that in those conditions it happened and probably frequently enough to make a difference. For multi-cellular organisms the picture is completely different and it likely wouldn't matter nearly as much.
        gumby 3y ago
        Let me phrase it a different way: I don't think there are any organisms selecting for being genetically modified in petri dishes by researchers in research labs. I consider the gene transfers by lightning to be the equivalent of that. Unsurprisingly there are organisms that seem to preferentially strike (and mutate) in hospitals, but have they (yet?) selected for some special preference for, say, urban hospitals? I doubt it, though it would be cool (and probably frightening) if so. That situation would be more likely to evolve than the researcher case.
- klyrs 3y ago
  Proper mutant, hell. Mama's gettin' chloroplasts. Just... zap me up in a vat of algae.
  - marcosdumay 3y ago
    Hum... I know it's a joke, but just to point, chloroplasts aren't expressed by genes.
    - klyrs 3y ago
      sigh... I know, I know.
dpflan 3y ago
As another pointed out, isn't this early experiment highly relevant to the discussion? - https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
xkcd-sucks 3y ago
Up until recently this was state of the art (or, spraying DNA really hard onto cells, or putting cells in a DNA-laced salty spike trap). All pretty barbaric methods really, and still widely used. The fewer cells comprising the organism/thing the more likely it is to have any likelihood of a meaningful result. Which is not much at best because like the most fundamental capability of a living cell/organism is keeping out foreign DNA and not integrating and reproducing it if some does get in. So the approach is to do it on a massive scale and design in some easy way of recognizing/selecting for the successful ones i.e. if it happens in nature it's vanishingly unlikely that the zapped genotype lasts for more then a generation, just like with any other random mutation. The likelihood of a zapped-in chunk being a major evolutionary advantage could be higher than that caused by an environmental factor, just because it can transfer big chunks of something that was once useful to someone else, versus the more point ish mutations caused by radiation etc. In relation to the eels/lightning, the mechanism is totally plausible but the question should be more how meaningful is it in comparison to all the other ways DNA is transferred like viruses/bacteria/fungus, radiation, bad luck, etc. Generally other unicellular critters are somewhat better at sneaking in weird DNA than environmental factors because it's their trained profession or something

tomohelix 3y ago

Yes! Electroporation is literally just subjecting the cells to a strong electrical potential. A lightning can definitely do the trick in some conditions. Many cells will die, but it is a sacrifice natural selection is willing to make. Although, this doesn't mean you zapping someone with enough lightning and they can become the flash. The electroporation process is one way of damaging the cell just enough to make them take in foreign DNA. Think of it like poking holes in the cell and DNA got in. Whether that DNA get recombined or not depends on other processes, which might also get activated as a stress response to the damage. But it is entirely random. So the DNA coding that specific function/protein must be available in the environment first, and the cell must survive the process of getting struck by Zeus and be lucky enough to do the recombination just right to retain that piece of DNA to produce a proper mutant. Lots of entropy here, like someone said elsewhere. But that is life. Do it enough time and maybe something fun come out of it.

karim79 3y ago
So then, I suppose, the 'lethal zone' would be heavily dependant on the power of the lightning strike, the volume of the available body of water, the density of life within the water, and probably thousands of other factors. It would perhaps be much worse for ocean-dwellers than for fresh-water life due to the conductivity differences. I would love to see a computer simulation of this, e.g., for each type of aquatic ecosystem, what would be the recombination sweet-spot or optimal conditions for genetic recombination within a lightning-affected area.
gumby 3y ago
> A lightning can definitely do the trick in some conditions. Many cells will die, but it is a sacrifice natural selection is willing to make. While I agree with Dennett,* I don’t think agency is correctly ascribed here, unless you can find selection for locations of increased lightning incidence(!). It’s more like “any survivors remain subject to natural selection, as did those unfortunates that did not survive” * https://en.wikipedia.org/wiki/Intentional_stance https://en.wikipedia.org/wiki/Intentional_stance
- cariaso 3y ago
  It's more than natural selection. https://en.wikipedia.org/wiki/Electroporation https://en.wikipedia.org/wiki/Electroporation enables gene transfer.
  - gumby 3y ago
    Yes, that was the topic of the article. I am just dubious that a location that got a lot of lightning could be selected for, though lightning is not uniform across the globe. But it's a rather crude factor and hard to defend against on a micro scale!
    - jacquesm 3y ago
      In the past there were periods of billions of years at a stretch with not much else going on that single celled organisms being zapped by lightning. You'd think that in those conditions it happened and probably frequently enough to make a difference. For multi-cellular organisms the picture is completely different and it likely wouldn't matter nearly as much.
      - gumby 3y ago
        Let me phrase it a different way: I don't think there are any organisms selecting for being genetically modified in petri dishes by researchers in research labs. I consider the gene transfers by lightning to be the equivalent of that. Unsurprisingly there are organisms that seem to preferentially strike (and mutate) in hospitals, but have they (yet?) selected for some special preference for, say, urban hospitals? I doubt it, though it would be cool (and probably frightening) if so. That situation would be more likely to evolve than the researcher case.
klyrs 3y ago
Proper mutant, hell. Mama's gettin' chloroplasts. Just... zap me up in a vat of algae.
- marcosdumay 3y ago
  Hum... I know it's a joke, but just to point, chloroplasts aren't expressed by genes.
  - klyrs 3y ago
    sigh... I know, I know.

dpflan 3y ago

As another pointed out, isn't this early experiment highly relevant to the discussion? - https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment

xkcd-sucks 3y ago

Up until recently this was state of the art (or, spraying DNA really hard onto cells, or putting cells in a DNA-laced salty spike trap). All pretty barbaric methods really, and still widely used. The fewer cells comprising the organism/thing the more likely it is to have any likelihood of a meaningful result. Which is not much at best because like the most fundamental capability of a living cell/organism is keeping out foreign DNA and not integrating and reproducing it if some does get in. So the approach is to do it on a massive scale and design in some easy way of recognizing/selecting for the successful ones i.e. if it happens in nature it's vanishingly unlikely that the zapped genotype lasts for more then a generation, just like with any other random mutation. The likelihood of a zapped-in chunk being a major evolutionary advantage could be higher than that caused by an environmental factor, just because it can transfer big chunks of something that was once useful to someone else, versus the more point ish mutations caused by radiation etc. In relation to the eels/lightning, the mechanism is totally plausible but the question should be more how meaningful is it in comparison to all the other ways DNA is transferred like viruses/bacteria/fungus, radiation, bad luck, etc. Generally other unicellular critters are somewhat better at sneaking in weird DNA than environmental factors because it's their trained profession or something