> "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.
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.
> 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”
But, to nitpicking, I guess you could say the selection came after the gene got recombined. Surviving the zap and was lucky enough to do the recombination still do nothing. The effect of the recombination, i.e. the expression of the foreign gene, is the interesting part. If it confers an advantageous trait to the mutant, that mutant get selected for in the game of life. If it doesn't, which is most often the case, it is selected against, and would be quickly removed from the genetic pool.
We do this selection quite often in the lab so perhaps it unconsciously leaked out in my phrasing.
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!
It’s also worth noting that early in earth’s history, it was geologically very active and thus resulted atmosphere with all kinds of extreme weather—including lightning storms.
I don’t know how likely spontaneous recombination is, but those two data points make it seem plausible enough that electricity may have had an important role in the development of life on earth.
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.
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.
There were no organisms selecting to reproduce either. Of course, natural selection is largely a random process that organisms are subject to rather than a process that requires them to be active agents.
I feel there is a useful analogy in what happens in toxic environments. In areas where there are high levels of arsenic, for example, you find a limited ecology of organisms adapted to tolerate it, and I think I am right to say that they do not do well outside of this environment, as the mechanisms of tolerance are sub-optimal where they are not needed.
The most relevant situation would be where the environmental toxin is mutagenic. My uninformed guess is that adaptation to that environment would typically involve mechanisms to reduce susceptibility to the toxin's mutagenic effect, and, as in the case with other toxins, organisms so adapted would be out-competed in areas where the toxin is not present.
I guess we have examples in the microbes which have adapted to live in areas of high radiation, but I do not know how they fare elsewhere.
Update: D. radiodurans is an example, but it has been suggested that its tolerance is simply a side effect of a mechanism for dealing with prolonged cellular desiccation - another sort of environment where they do well.
That's cause and effect reversed! Organisms don't select, it's selection pressure that determines which organisms get to the age of reproduction and whose offspring are viable. Some outside factor (environment, another organism) needs to supply the pressure. Absent pressure life will occupy whatever room you give it until it runs up against some kind of boundary and then that pressure will take over again.
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.
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
As a backdrop for reading this, electroporation is one type of transfection, which is a method to "artificially introducing nucleic acids (DNA or RNA) into cells, utilizing means other than viral infection."
You can also basically squeeze cells to do this, as well as put them under higher hydrostatic pressure.
I also think I know the internal project name for something...
Perhaps the most brutal way of introducing nucleic acids into cells is microinjection: you make a really, really fine needle, jab it into a cell's nucleus, and inject a DNA solution. It is incredibly painstaking work, does kill a lot of the cells, and making the needles is a black art, but it works for all sorts of cells, even those resistant to chemical methods, so it is sometimes still useful.
Is there some state of the art Handbook (Springer Taylor&Francis type) that you could recommend on physical methods of Transfection that goes into the physics of it?
We need more of this sort of science, trying out weird ideas just because. A lot of hypotheses will be dead ends, but surprising discoveries more than make up for it.
That’s quite a lot of entropy and enough to compete with or at least alongside natural selection in that biome.
I wonder if there are other sources that promote recombination in nature.
Really messes up the whole model for that theory. Instead of assuming transitional forms or so many ancestors passing sex linked traits that were selected for, there really can be spontaneous same generation mutation that can become sex linked or be passed, with no gradual multigenerational aspect.
Viral infection is an example of another example of horizontal gene transfer. Some bacteria have developed other ways to take advantage of this process easily. Darwin might be surprised by this, but the experiments that first showed evidence for this are nearly a century old now so its nothing new for the field today.
Some bacteria are capable of naturally taking up genetics of nearby bacteria. There are other methods for horizontal gene transference. It happens more in simple organisms, but even humans are thought to have DNA in a genome transferred by ancient viruses.
"I collected the instruments of life around me, that I might infuse a spark of being into the lifeless thing that lay at my feet. It was already one in the morning; the rain pattered dismally against the panes, and my candle was nearly burnt out, when, by the glimmer of the half-extinguished light, I saw the dull yellow eye of the creature open; it breathed hard, and a convulsive motion agitated its limbs." (Chapter 5)
Its a byproduct of the electricity. No use case. Authors were turned on to try it because this is already a lab technique in a much more controlled manner to get some nucleic acids into some cell. They wanted to see if there is an example of this in nature and the electric eel seemed like a good potential source of the electricity.
Eel is just providing the shock not the DNA. There is an advantage on the otherhand for species to be susceptible to this sort of horizontal gene transfer. E.g. bacteria populations will uptake environmental dna like this on the offchance they take up something beneficial (usually from other bacteria populations in the area that might have genes giving an advantage in that environment).
A lot more likely to do odd things to bacteria and other simple organisms in the water than say local fish. Not to mention all the biota that's probably growing in and around the eel itself. Do they have gut bacteria for example? If so what's it do to them?
To answer that there are two main factors:
1) For this kind of single instance gene transfer to have an evolutionary effect, it will need to happens to germ-line cell (so an egg or sperm cell in a multi-cellular organism, or in a single-celled organism). Otherwise the mutation won't be inheritable and it won't be evolution, just mutation.
2) The organism(s) affected by this gene transfer would need to be under some evolutionary pressure that would benefit from extra genetic variance. Genetic variance in itself is not a driver of evolution, evolutionary pressure is, which does need the variance to actually do anything. Pressure is the sculptor and variance is the clay, without one of those there won't be a statue.
Also, normally most random mutations are either negative or neutral (there's a lot more ways an organism can be dead than alive), so I would suspect this might also be true of gene transfers. Though gene transfers from environmental DNA isn't as random as direct genetic mutation, so perhaps there's something interesting happening there. But I wouldn't be surprised to find out that the risk of cancer or viral infections would be higher.
> "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....
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.
> 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
It was a (dumb) joke. The phrase I used came from Shrek.
https://knowyourmeme.com/memes/some-of-you-may-die
But, to nitpicking, I guess you could say the selection came after the gene got recombined. Surviving the zap and was lucky enough to do the recombination still do nothing. The effect of the recombination, i.e. the expression of the foreign gene, is the interesting part. If it confers an advantageous trait to the mutant, that mutant get selected for in the game of life. If it doesn't, which is most often the case, it is selected against, and would be quickly removed from the genetic pool.
We do this selection quite often in the lab so perhaps it unconsciously leaked out in my phrasing.
It's more than natural selection. https://en.wikipedia.org/wiki/Electroporation enables gene transfer.
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!
Behold: https://phys.org/news/2021-09-lake-maracaibo-lightning-capit...
It’s also worth noting that early in earth’s history, it was geologically very active and thus resulted atmosphere with all kinds of extreme weather—including lightning storms.
I don’t know how likely spontaneous recombination is, but those two data points make it seem plausible enough that electricity may have had an important role in the development of life on earth.
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.
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.
There were no organisms selecting to reproduce either. Of course, natural selection is largely a random process that organisms are subject to rather than a process that requires them to be active agents.
I feel there is a useful analogy in what happens in toxic environments. In areas where there are high levels of arsenic, for example, you find a limited ecology of organisms adapted to tolerate it, and I think I am right to say that they do not do well outside of this environment, as the mechanisms of tolerance are sub-optimal where they are not needed.
The most relevant situation would be where the environmental toxin is mutagenic. My uninformed guess is that adaptation to that environment would typically involve mechanisms to reduce susceptibility to the toxin's mutagenic effect, and, as in the case with other toxins, organisms so adapted would be out-competed in areas where the toxin is not present.
I guess we have examples in the microbes which have adapted to live in areas of high radiation, but I do not know how they fare elsewhere.
Update: D. radiodurans is an example, but it has been suggested that its tolerance is simply a side effect of a mechanism for dealing with prolonged cellular desiccation - another sort of environment where they do well.
https://en.wikipedia.org/wiki/Deinococcus_radiodurans#Evolut...
That's cause and effect reversed! Organisms don't select, it's selection pressure that determines which organisms get to the age of reproduction and whose offspring are viable. Some outside factor (environment, another organism) needs to supply the pressure. Absent pressure life will occupy whatever room you give it until it runs up against some kind of boundary and then that pressure will take over again.
> ...though lightning is not uniform across the globe.
If there is a natural laboratory for this, this would be it:
https://en.wikipedia.org/wiki/Catatumbo_lightning
The entire early earth was bombarded by lightening on an almost constant basis due to a number of factors.
Proper mutant, hell. Mama's gettin' chloroplasts. Just... zap me up in a vat of algae.
Hum... I know it's a joke, but just to point, chloroplasts aren't expressed by genes.
sigh... I know, I know.
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.
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
As another pointed out, isn't this early experiment highly relevant to the discussion?
- https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
As a backdrop for reading this, electroporation is one type of transfection, which is a method to "artificially introducing nucleic acids (DNA or RNA) into cells, utilizing means other than viral infection."
You can also basically squeeze cells to do this, as well as put them under higher hydrostatic pressure.
I also think I know the internal project name for something...
While mostly used for plants, there's another method that's essentially shooting cells with bullets coated in genes
https://en.m.wikipedia.org/wiki/Gene_gun
Perhaps the most brutal way of introducing nucleic acids into cells is microinjection: you make a really, really fine needle, jab it into a cell's nucleus, and inject a DNA solution. It is incredibly painstaking work, does kill a lot of the cells, and making the needles is a black art, but it works for all sorts of cells, even those resistant to chemical methods, so it is sometimes still useful.
Is there some state of the art Handbook (Springer Taylor&Francis type) that you could recommend on physical methods of Transfection that goes into the physics of it?
Transfection by heat shock is also a possibility. Anything that creates transient pores on the cell membrane should work, at least in theory.
You can use chemicals too.
We need more of this sort of science, trying out weird ideas just because. A lot of hypotheses will be dead ends, but surprising discoveries more than make up for it.
Reminds me of the Miller Urey Experiment:
https://en.wikipedia.org/wiki/Miller%E2%80%93Urey_experiment
That’s quite a lot of entropy and enough to compete with or at least alongside natural selection in that biome.
I wonder if there are other sources that promote recombination in nature.
Really messes up the whole model for that theory. Instead of assuming transitional forms or so many ancestors passing sex linked traits that were selected for, there really can be spontaneous same generation mutation that can become sex linked or be passed, with no gradual multigenerational aspect.
Viral infection is an example of another example of horizontal gene transfer. Some bacteria have developed other ways to take advantage of this process easily. Darwin might be surprised by this, but the experiments that first showed evidence for this are nearly a century old now so its nothing new for the field today.
https://en.m.wikipedia.org/wiki/Horizontal_gene_transfer
Some bacteria are capable of naturally taking up genetics of nearby bacteria. There are other methods for horizontal gene transference. It happens more in simple organisms, but even humans are thought to have DNA in a genome transferred by ancient viruses.
https://en.wikipedia.org/wiki/Transformation_(genetics) https://en.wikipedia.org/wiki/Horizontal_gene_transfer
So Mary Shelley wasn't too far off.
"I collected the instruments of life around me, that I might infuse a spark of being into the lifeless thing that lay at my feet. It was already one in the morning; the rain pattered dismally against the panes, and my candle was nearly burnt out, when, by the glimmer of the half-extinguished light, I saw the dull yellow eye of the creature open; it breathed hard, and a convulsive motion agitated its limbs." (Chapter 5)
> I realized that electric eels in the Amazon River could well act as a power source...
Somewhere, someone is already thinking about mining crypto with these creatures.
Turns out it's you!
This reminds me of a fascinating book I read a few years ago about experiments using electricity to promote cellular healing and regeneration.
It was called The Body Electric.
https://www.amazon.com/Body-Electric-Electromagnetism-Founda...
Do they evolved to do that? If that’s the case, what’s the use case? If not, it’s just a weird artifact of producing electricity?
Its a byproduct of the electricity. No use case. Authors were turned on to try it because this is already a lab technique in a much more controlled manner to get some nucleic acids into some cell. They wanted to see if there is an example of this in nature and the electric eel seemed like a good potential source of the electricity.
Right. There is no genetic advantage for the electric eel to inject its DNA into others per se.
Eel is just providing the shock not the DNA. There is an advantage on the otherhand for species to be susceptible to this sort of horizontal gene transfer. E.g. bacteria populations will uptake environmental dna like this on the offchance they take up something beneficial (usually from other bacteria populations in the area that might have genes giving an advantage in that environment).
I guess I'm not being precise in my comments. 100% I am agreed the eel's DNA is not part of the equation here.
It's not (usually) the eel's DNA that gets injected, it's just whatever is floating near the victim's cells.
(Im)precisely. As it were.
A lot more likely to do odd things to bacteria and other simple organisms in the water than say local fish. Not to mention all the biota that's probably growing in and around the eel itself. Do they have gut bacteria for example? If so what's it do to them?
What’s the use case for anything really ?
Propagation is the name of the game, and perhaps the ultimate measuring stick for "useful" and so use cases.
Propagation to what end?
Hopefully not!
Origin story of Electro from Spiderman just made a jump from fantasy to science-fiction!
So, what is the impact of lightning I wonder? If it hits a tree, there's a lot of bacterial and other things in the mix - far more than just the tree.
"Lightning-triggered electroporation and electrofusion as possible contributors to natural horizontal gene transfer"
https://linkinghub.elsevier.com/retrieve/pii/S15710645130005...
Cool, so Blanka from Street Fighter is plausible, its not just made up fantasy bullshit.
Good to know.
Title says "genetic material". Is not the same as gene
Warning: Dark Humour
Japanese experiments are always on another level.
i wonder is there more measurable evolution/diversity within the vicinity of e-eel habitats? or cancers?
NB. i too know not one jot of which i speak
To answer that there are two main factors: 1) For this kind of single instance gene transfer to have an evolutionary effect, it will need to happens to germ-line cell (so an egg or sperm cell in a multi-cellular organism, or in a single-celled organism). Otherwise the mutation won't be inheritable and it won't be evolution, just mutation.
2) The organism(s) affected by this gene transfer would need to be under some evolutionary pressure that would benefit from extra genetic variance. Genetic variance in itself is not a driver of evolution, evolutionary pressure is, which does need the variance to actually do anything. Pressure is the sculptor and variance is the clay, without one of those there won't be a statue.
Also, normally most random mutations are either negative or neutral (there's a lot more ways an organism can be dead than alive), so I would suspect this might also be true of gene transfers. Though gene transfers from environmental DNA isn't as random as direct genetic mutation, so perhaps there's something interesting happening there. But I wouldn't be surprised to find out that the risk of cancer or viral infections would be higher.
This feels like the plot of a superhero movie.
This mechanism (electroporation) is one of the first steps in mass-producing the mRNA vaccine.