I'd really love to see a video on extinct mammalian groups such as the multituberculates, (or any other extinct mammals which can't be categorized as placentals, marsupials or monotremes)
@@mothlightmedia1936 that would be fantastic but honestly every video you make is absolute gold...I just found your channel this month and it is already my favorite evolutionary history channel on RUclips
It isn't insane, it is the basic principle of how this universe works. Smallest and simplest Atom in the universe? Hydrogen, literally the energy source for everything... it goes on and on. The reason that seem insane to you is because you were told by society for so long, that the small individual can't achive anything meaningfull.
I've been a fan since this channel started. You've really improved dramatically. It's cool to see the little changes from video to video. You're doing everything right. I hope it pays off for you.
@@jonstfrancis the fact that viruses could be older than life it's... Poetic! Although unpleasant, and often times dangerous, viruses make me realize how impressive it is the fact that a chemical reaction can replicate itself... And I'm made of it... Man, I love how life works, and I am very thankful to be part of it!
@@dibershai6009 they are called virophages and they are parasites of those large mamoviruses that were mentioned in the video. They don’t infect them in the typical way, as the host being a virus lacks the self replication factories inside. Rather they wait for the large virus to infect a cell, and the hijack the process for themselves. This causes the host cell to make copies of the virophage rather than the Mamovirus.
Feel like you should've mentioned that arguably the main reason viruses aren't considered living is because they lack homeostasis. You brought up the blurred line of living vs chemical and even attributed it to them not self-replicating but didn't mention homeostasis
I favour the theory that they are (relics of) an ancient horizontal gene transfer mechanism, not predating the cell, but predating what we would now call a “species”.
Prions are what makes me propend for the second theory, as they show that something created by a cell can accidentally become a pathogen agent, in the right (wrong?) conditions.
@@adambartlett114 Maybe because they have to be the right environment to replicate, usually inside an animal. Since neurological prions tend to eventually make the host non viable, could be the reason why prions (and prions disease) are not more prevalent. Now there is a good reason to go vegan or at least culture animal protein rather than eat meat that used to be a live animal.
@@creme1858 Prions aren't *just* misfolded protiens, they're rogue protiens that also replicate that misfold upon other protiens which enables their virulence. Not all misfolded protiens become prions, it's the additional capacity for pathogenicity that makes a misfolded protien a prion. You can have proteopathy, or misfolds, without that misfold becoming a virulent pathogen & is the cause of several neural degenerative diseases & genetic disorders.
Great video! And thank you for the size comparison. It really helps to put things in context! I guess it wouldn’t hurt to be a bit more specific about the examples. Like... a coronavirus, a red blood cell, an E. coli and so on. Things commonly known by the average Joe and Jane lol
Early life and evolution in general is such an interesting topic! I was thinking of finding some nonfiction books to read on this. Anyone here have good reads about this kind of stuff?
Life on a Young Planet: the First 3 Billion Years by Andrew H. Knoll. Really excellent book, fascinating reading, by an actual scientist in this field.
There is no line between life and chemistry. It's just more useful to say that animals, plants, and things like that are different than rocks, air and water
@@TheExtremeCubeThen are mites alive? They don't have consciousness. OP is talking about how some people refuse to call viruses alive despite saying bacteria is alive. To OP it's all just chemicals causing reactions and when the reactions and interactions get complex enough, we call it life.
@@Twiska What makes you think Mites are not conscious? I have no reason to believe they aren't, given that they have a nervous system, senses and actively move. It's organisms like plants and bacteria that it is harder to make a case for that they have consciousness, but you could do it since consciousness is not a property of neuronal computation (evidence is that you have highly complex areas of your brain with no consciousness like the cerebellum).
These videos are excellent sir. You have a great narration voice and deliver the info in a superb fluid way, being a Zoologist with a penchant for Reptiles and Amphibians I find myself over the years concentrating on these areas too much. These videos have taught me so much about many other lifeforms and processes for which I am extremely grateful. I am currently reading books by Carl Zimmer on Viruses. Please keep this up thankyou. I subscribed to you today :)
@@bodeeangus9957really depends on global agendas , if they use crisper to edit the genes and make it compatible , but this would take billions of dollars and many decades of clinical trials but with science anything is possible given if it is within the realm and parameters that your working with and you fully understand the limitations of the law of physics
I'm amazed that during the current plague, millions have not viewed this video. I wonder how many of the covid spokesmen & hawkers have even the basic info contained herein. Keep up the superb superb work!
If you can find parts of the ancient virus's DNA in modern animals, does that mean you could technically remove them and piece it back together? Would be pretty cool if you could.
It will be cool, but disastrous. We barely survived ( though not entirely, because the virus is evolving ) Covid-19 , let’s not bring back ancient viruses to f**k us up.
i was thinking about how yawning must've evolved while at work today. from what i know, most vertabrates yawn so it must either be a very ancient trait or convergent evolution right? but since we dont really even know the function of yawning for sure, i imagine that probably complicates things a bit.
Viruses can be used to genetically engineer specific cell types within an organism as well. As Crispr proteins and the associated genetic material could be added to a virus with the a base plate that would infect said cell type. Such a mechanism should theoretically make it possible to wipe out retroviruses from people and do all sorts of work as well.
Viruses are actually pretty important to life on earth as we know it. For example, there are plenty of viruses that kill bacteria, and without them, bacteria would overrun the oceans.
I love how he almost sounds like he's purely speaking as a very interesting and fun book to read, with enthusiasm. Then he mentions "nightmare inducing" when talking about wasps and Idk if that was character breaking but it was hilarious
"...blur the lines between life and chemical reactions..." This is so interesting to me. On one level of analysis, all of life, and all of reality for that matter, can be seen as chemical reactions.
It took me a couple times watching this video over time to truly understand that beginning; viruses are so many times smaller than single cell organisms it's crazy.
I think the best explanation on virus evolution is that they evolved from bacteria/single celled organisms. bacteria, lets say, evolves in a symbiotic relationship between another organism, and this relationship becomes so strong and comprehensive (it lives its whole life cycle in the relationship) and never depends on anything but the host organism, leading eventually it to lose the reproduction capability on its own, as if its not needed, having it just takes extra energy without giving anything back. evolving into a virus would be especially beneficial in a poor-energy environment, where the host can just about sustain itself, but there is no surplus of energy to waste. very simple principle of whatever is beneficial, survives. evolution doesn't attempt to create more complex or life-like organisms. if its more beneficial just to be able to sustain oneself until it finds a host, then that will survive over those who waste their energy on something else as well.
Can you please explain in a video why elephants, rhinos, large felynes and other large animals have went extinct everywhere else, but still survive in africa? Like the American lion or the woolly rhino.
@@mothlightmedia1936 it doesn't have to be your next video. You can decide what you want to do next since everything you post is gold and very interesting. You deserve more subscribers.
Surprised you went through this without mentioning plasmids despite mentioning the bit around 7:50, which seems far weaker. Simplified, they're a bacterial mechanism of encapsulating and communicating genetic information with one another, which can involve sending genetic information outside of the cell with an envelope, and(at least when I was in college) it was thought that this was a likely origin of viruses(if not THE likely origin). Not sure if any new knowledge has come about that makes this especially unlikely. It's very easy to imagine a plasmid that evolved to encourage production of itself and was likely even beneficial, but eventually came to be so strong as to completely hijack the machinery of any cell that received it, or simply lost its ability to be ejected(but not inject) and would accumulate until host cell death as a result. Sorry if any details are mistaken, it's been a long time since college. I personally also think that the existence of at least four different kinds of self-replicating(directly or indirectly) schema(cellular life, viroids, viruses and prions) is ample evidence to believe that different viruses may have originated independently in any number of ways. Some larger viruses having "degenerated" from cellular life doesn't seem too improbable either, for example.
When you mentioned the viroids being just a bundle of genetic material, it got me thinking; what if viroids are the result of the RNA escape hypothesis you mentioned earlier? It would still be possible for the viroids to mutate or even start out with a coating too. I find it pretty unlikely that viruses would evolve first, because they wouldn't even have the necessary parts to replicate themselves anyways, even if they're extremely simple.
I'm with you on this. I also think that different viruses can have different origins, so it's possible that every origin theory mentioned in the video is true. Parasitic beings tend to reduce their complexity, and used to be more complex before taking the parasitic path. So the similitudes we see in viruses are only because we are seeing the end result, but different viruses could came from very different organisms.
The hypothesis is that retro viruses evolved first from the first metabolism to evolve, and the possibility of an RNA world. The metabolism happened first followed by cells (archaeal & bacterial.) This appears to have happened quickly (in geological time) so maybe the RNA elements could also have had to form a capsule to invade cells. Unfortunately for the hypothesis todays bacteriophages are DNA based, not RNA or even retro-viruses.
since each time virus infects other cells and in case of ERVs they nest themselves in unique place after each infection. By this having ERVs in 2 different species implies a common ancestor that got this retrovirus and its remnants were passed down further. The probability that the retrovirus nested itself a few times in the exact same places is highly unlikely. What's more some of these ERVs are mutated in the same way, making it even more unlikely to happen separately.
We would consider other parasite's alive, so I would be leaning towards virus's being alive but also similar to a hybrid of spore's/plant pollen etc. Sorta like a genetic seed spore.
The volatile environment of early earth would be highly detrimental to RNA and its simplicity . What evolutionary pressures would allow them to evoke and what hosts did they initially infect?
I don’t envy geneticists. I’m a neurology student. I literally study the most complex machine in the universe and one of the least understood fields of science, and I think their job is still far more confusing.
He just explained it, bacteria are alive and have the proteins and things that it needs to procreate, while viruses are not alive and don't have the proteins and things it need to procreate by itself.
Just because two animals are infected by the same virus doesn't mean that the virus infected their common ancestors - viruses often jump between species.
Viruses aren't all pathogens. Even some of those which are, ie phages, help people. But beyond that, some think that the nuclei of eukaryotic cells derive from viruses, and it's likely that placentas evolved with the aid of a virus. To name but a few viral effects positive for all eukaryotes and for us placental mammals.
Generally, I like your educational videos. But the lack of overall structure (absence of course design) and the monotone delivery make it hard to see how the parts and videos fit together. Because of other production values, you may still generate a lot of views.
Could it be, that the blind watchmaker got lucky and out of pure Randomnes some aminoacids formed some kind of Viroid, that got attached to a multicell organism, wich enabled its survival in the first place, if it didn't reduced the fitness for survival?
So this distills theory down to whether or not DNA/RNA existed autonomously before cellular formations and possible caused cellular formations or; Cellular formations occurred before/simultaneously and acted as micro-segregating environments for autonomous DNA/RNA or autonomous proteins that became RNA/DNA, thus forming RNA/DNA. OR perhaps its somewhere in between.... perhaps abundant early uranium leeched radiation through marine vents, where chemically derived organic proteins that had settled near the bottom, would be churned upwards towards surface waters. Random congealment of the proteins (like snowflake formations) forming proto DNA and RNA, while creating connective lipid congealment's as a by-product. the inevitable trapping of congealed proteins within proto cellular lipid structures, would be continually exposed to intense radiation upon each churning upward lift, damaging proto-RNA/DNA structures within those proto-cells at random until only the most rigid radiation resistant formation (real proto-RNA/DNA) was left behind in non-reproducing proto-cells. These resilient proto-cell structures would naturally shrink and expand in palpating motions by thermal energy exposure near the vents, making their cell walls penetrable to new RNA/DNA material which would react at random with the internal "well-formed" proto-DNA/RNA. This would eventually cause a proto-cell to expand and "bud off" a mirror image of itself in the first act of "Thermal energy dependent proto-cellular replication". This would explain how advanced RNA/and DNA could form from radiation, and how the resultant "phenomena of life" is dependent on an energy input for reproduction. Its also a fairly simple process, which would automatically occur once surface oceans form, explaining why life seemingly "immediately arises" after earths cooling began. It might insinuate that all earth-like planets would have this happen and that the "phenomena of life" is always convergent in basic micro-design.
The fact that the virus is made up of protein tells you something about when it evolved. It did NOT evolve before cells. Why? Because proteins do NOT appear out of random chemical processes in Nature. They only get created inside cells. In fact, they are produced in the nucleus. An important fact to keep in mind is that proteins when created in the nucleus don't work! They have to be folded in very precise ways before they are capable of carrying out their intended function. No specific fold no functionality at all. That folding, too, is carried out in the nucleus of the cell. After that, there is a quality assurance stage that allows the properly folded protein to leave the nucleus and go to the cell proper where it will perform its intended function. If the protein fails the Q.A. check it is destroyed! So, if trillions of years were granted to create a protein randomly in Nature; that would avail nothing as it wouldn't have the folding required to make it functional. Also, as you say, viruses need cells to replicate. So, whatever protein appeared randomly would not be able to replicate and quite quickly would be destroyed by ultraviolet light in the environment! Now, something that goes on in the creation of human red blood cells may provide a clue to the origin of viruses. The red blood cell in all mammals starts of with a nucleus; but that nucleus for whatever reason is ejected from the cell. This happens in us millions of times every second. www.sydney.edu.au/research/opportunities/opportunities/1165?faculty=11 It may be that whatever started this process, called enucleation, in our far distant past led to the ejection of parts of the nucleus in a form that roughly complies with what we now call a virus. When I say, our, I mean to refer to all mammals. Birds, reptiles, amphibians and fish do not enucleate. Another curious thing about red cells, called erythrocytes, is they don't possess organelles such as the mitochondria. The process that purged them from mammalian cells long ago (assuming they were purged) may have dumped them out as incomplete protein chains which acted like modern day viruses (i.e. reentered the cell and replicated with the help of the cell).
I'd really love to see a video on extinct mammalian groups such as the multituberculates, (or any other extinct mammals which can't be categorized as placentals, marsupials or monotremes)
Yeah I think that would make a good video, I've been meaning to make a video on the evolution of live birth in mammals for ages as well.
@@mothlightmedia1936 that would be fantastic but honestly every video you make is absolute gold...I just found your channel this month and it is already my favorite evolutionary history channel on RUclips
Thank you man I appreciate it
I'm here for the evolution of the placenta!
@@LDrosophila Yes that would be neat!
Viruses be like "I'm going to seize these means of reproduction"
He tried to avoid it too lol 😂 "seize the means..... to reproduce...."
Damn socialists!
Viruses are commies now.
@@ok1025 i mean they act the same lol
@@hectorzero8545 Based
Fascinating stuff! I’m glad I found this channel, I’ve been binging on your work all morning haha
Thank you I hope you've enjoyed them
Every evolutionary biology youtuber now be like
*"mmmh...perhaps I should be talking about viruses in my next video"*
Nesslig 20 as they should. Hopefully the audience learns and becomes more aware.
"now be like"? please.
@@geoffreystuttle8080 ?
I know you
Covid has a 94% comorbidity rate. End the lockdowns
It's insane how something so small and simple can have such a big impact on the world
I just learned about viroids and I found that far more fascinating than viruses
The planndemic!
It isn't insane, it is the basic principle of how this universe works. Smallest and simplest Atom in the universe? Hydrogen, literally the energy source for everything... it goes on and on.
The reason that seem insane to you is because you were told by society for so long, that the small individual can't achive anything meaningfull.
@@xhawkenx633 exactly !!
Numbers win. Same goes for bacteria.
I've been a fan since this channel started. You've really improved dramatically. It's cool to see the little changes from video to video. You're doing everything right. I hope it pays off for you.
Thank you and thank you for the advice in the past, your name doesn't proceed you.
There are even some viruses that infect other viruses. That's a fact that's true nightmare fuel.
Which would lend to the theory that viruses are older than cellular life!
@@jonstfrancis the fact that viruses could be older than life it's... Poetic!
Although unpleasant, and often times dangerous, viruses make me realize how impressive it is the fact that a chemical reaction can replicate itself...
And I'm made of it...
Man, I love how life works, and I am very thankful to be part of it!
How do viruses infect each other? I have heard about viruses infecting jerms but not other viruses!
Virus got to jonsfrancis before he could divulge its secrets...
@@dibershai6009 they are called virophages and they are parasites of those large mamoviruses that were mentioned in the video. They don’t infect them in the typical way, as the host being a virus lacks the self replication factories inside. Rather they wait for the large virus to infect a cell, and the hijack the process for themselves. This causes the host cell to make copies of the virophage rather than the Mamovirus.
Feel like you should've mentioned that arguably the main reason viruses aren't considered living is because they lack homeostasis. You brought up the blurred line of living vs chemical and even attributed it to them not self-replicating but didn't mention homeostasis
@10:18 wow, Ken Ham is a Patron... I know it's not AIG Ken Ham, but it'd be funny if it was 😅
I favour the theory that they are (relics of) an ancient horizontal gene transfer mechanism, not predating the cell, but predating what we would now call a “species”.
Don't forget prions which are smaller than viruses and can replicate without genetic material.
Prions are the weirdest shit in the world.
Prions are what makes me propend for the second theory, as they show that something created by a cell can accidentally become a pathogen agent, in the right (wrong?) conditions.
@@adambartlett114 Maybe because they have to be the right environment to replicate, usually inside an animal. Since neurological prions tend to eventually make the host non viable, could be the reason why prions (and prions disease) are not more prevalent. Now there is a good reason to go vegan or at least culture animal protein rather than eat meat that used to be a live animal.
@@LimeyLassen literally just misfolded protein lol
@@creme1858
Prions aren't *just* misfolded protiens, they're rogue protiens that also replicate that misfold upon other protiens which enables their virulence.
Not all misfolded protiens become prions, it's the additional capacity for pathogenicity that makes a misfolded protien a prion.
You can have proteopathy, or misfolds, without that misfold becoming a virulent pathogen & is the cause of several neural degenerative diseases & genetic disorders.
I can't believe I've been watching SciShow and Eons for years and YT never showed me this channel until recently
Ikr
Great video! And thank you for the size comparison. It really helps to put things in context! I guess it wouldn’t hurt to be a bit more specific about the examples. Like... a coronavirus, a red blood cell, an E. coli and so on. Things commonly known by the average Joe and Jane lol
I’ve been thinking about making a video like this, good stuff!
Thank you and, do it
What video editing software do you use? Your production quality is amazing
I use gimp to edit images and hit film pro to put everything together
I didn't know viroids were a thing, it really does blur the lines between life and chemical reactions.
Early life and evolution in general is such an interesting topic! I was thinking of finding some nonfiction books to read on this. Anyone here have good reads about this kind of stuff?
The Aquatic Ape Hypothesis - Elaine Morgan. So it's not factual, but it is a working theory. It's not too deep that you think, how did I get here.
Life on a Young Planet: the First 3 Billion Years by Andrew H. Knoll. Really excellent book, fascinating reading, by an actual scientist in this field.
There is no line between life and chemistry. It's just more useful to say that animals, plants, and things like that are different than rocks, air and water
Couldn't you just say that life is just self-replicating chemistry?
Life involves consciousness which is not a chemical reaction.
@@TheExtremeCubeThen are mites alive? They don't have consciousness. OP is talking about how some people refuse to call viruses alive despite saying bacteria is alive. To OP it's all just chemicals causing reactions and when the reactions and interactions get complex enough, we call it life.
@@Twiska What makes you think Mites are not conscious? I have no reason to believe they aren't, given that they have a nervous system, senses and actively move. It's organisms like plants and bacteria that it is harder to make a case for that they have consciousness, but you could do it since consciousness is not a property of neuronal computation (evidence is that you have highly complex areas of your brain with no consciousness like the cerebellum).
These videos are excellent sir. You have a great narration voice and deliver the info in a superb fluid way, being a Zoologist with a penchant for Reptiles and Amphibians I find myself over the years concentrating on these areas too much. These videos have taught me so much about many other lifeforms and processes for which I am extremely grateful. I am currently reading books by Carl Zimmer on Viruses. Please keep this up thankyou. I subscribed to you today :)
Hey man, I love your videos. You have taught me a lot.
So could that wasp virus possibly be adapted to help organs from being rejected during organ transplants?
Doubtful, the human immune system is very different from an insect’s.
@@bodeeangus9957really depends on global agendas , if they use crisper to edit the genes and make it compatible , but this would take billions of dollars and many decades of clinical trials but with science anything is possible given if it is within the realm and parameters that your working with and you fully understand the limitations of the law of physics
This reinforced my theory that wasps are pure evil little creatures.
Well, it's their instinct, they don't know any better.
@@just_a_guy9688 I don’t support their instinct. They should just get a new one or sum idk
this is a very fascinating subject! thank you!!
viruses look so mechanical. They're like robot spiders.
@rent a shill well, thanks, that's cool to know
This channel is criminally underrated
I'm amazed that during the current plague, millions have not viewed this video. I wonder how many of the covid spokesmen & hawkers have even the basic info contained herein. Keep up the superb superb work!
This is not even gcse level biology that 15/16 year olds study
@@zakr1187 then how haven’t I learned this at 14?
One year later: What plague?
I'm already pretty good about the info but hearing you explain it was very nice.
Thank you for these videos! :)
I like this. Please do a part 2 on viruses!
What about the possibility that multiple different types of viruses developed via different methods at different times and/or places?
I think that is very likely true
You channel is amazing, though I will say that DNA viruses also exist. They mutate much slower than RNA viruses
If you can find parts of the ancient virus's DNA in modern animals, does that mean you could technically remove them and piece it back together? Would be pretty cool if you could.
It will be cool, but disastrous. We barely survived ( though not entirely, because the virus is evolving ) Covid-19 , let’s not bring back ancient viruses to f**k us up.
Excellent, especially the origin theories.
In hindsight, moth light was low-key pushing the bat soup theory 🦇
i was thinking about how yawning must've evolved while at work today. from what i know, most vertabrates yawn so it must either be a very ancient trait or convergent evolution right? but since we dont really even know the function of yawning for sure, i imagine that probably complicates things a bit.
Viruses can be used to genetically engineer specific cell types within an organism as well. As Crispr proteins and the associated genetic material could be added to a virus with the a base plate that would infect said cell type. Such a mechanism should theoretically make it possible to wipe out retroviruses from people and do all sorts of work as well.
Awesome video! Anyway we can a history of alligator, crocodile and caiman evolutions
Well coincidently my next video is on crocodiles, although not that exact topic.
Viruses are actually pretty important to life on earth as we know it. For example, there are plenty of viruses that kill bacteria, and without them, bacteria would overrun the oceans.
@mothlightmedia can you do a video of the evolution of duck billed platypus?
Yes I would like to, the problem is that the fossil record for the platypus is very bad but I'll see what I can do.
A virus is like a lifeform Junji Ito would design if he were god.
Why does this make sense? 😂
I love how he almost sounds like he's purely speaking as a very interesting and fun book to read, with enthusiasm. Then he mentions "nightmare inducing" when talking about wasps and Idk if that was character breaking but it was hilarious
Can't stop scratching watching this.
Great video! ❤
"...blur the lines between life and chemical reactions..."
This is so interesting to me.
On one level of analysis, all of life, and all of reality for that matter, can be seen as chemical reactions.
great video
Thank you
It took me a couple times watching this video over time to truly understand that beginning; viruses are so many times smaller than single cell organisms it's crazy.
Great channel name btw
I was eating a chipotle burrito when you brought the whole embedding eggs in living insects...thanks....
I think the best explanation on virus evolution is that they evolved from bacteria/single celled organisms. bacteria, lets say, evolves in a symbiotic relationship between another organism, and this relationship becomes so strong and comprehensive (it lives its whole life cycle in the relationship) and never depends on anything but the host organism, leading eventually it to lose the reproduction capability on its own, as if its not needed, having it just takes extra energy without giving anything back. evolving into a virus would be especially beneficial in a poor-energy environment, where the host can just about sustain itself, but there is no surplus of energy to waste.
very simple principle of whatever is beneficial, survives. evolution doesn't attempt to create more complex or life-like organisms. if its more beneficial just to be able to sustain oneself until it finds a host, then that will survive over those who waste their energy on something else as well.
Ppl should appreciate viruses more. There should be a whole museum dedicated to viruses and bacteria
There really isn't a line between life and chemical reactions
I agree, the point I was making was more that it doesn't feel like it and viruses remind us of this
When I was in junior high school I once said maybe we are just walking chemical reactions
There is a line. You learned that in 5th class probably....
@@Nazqua thanks! But I don't think I am
how are people not curious about this, should be 10m views+
Can you please explain in a video why elephants, rhinos, large felynes and other large animals have went extinct everywhere else, but still survive in africa? Like the American lion or the woolly rhino.
Yeah that actually sounds like a really good idea for a video
@@mothlightmedia1936 it doesn't have to be your next video. You can decide what you want to do next since everything you post is gold and very interesting. You deserve more subscribers.
Thank you I appreciate it
Surprised you went through this without mentioning plasmids despite mentioning the bit around 7:50, which seems far weaker. Simplified, they're a bacterial mechanism of encapsulating and communicating genetic information with one another, which can involve sending genetic information outside of the cell with an envelope, and(at least when I was in college) it was thought that this was a likely origin of viruses(if not THE likely origin). Not sure if any new knowledge has come about that makes this especially unlikely.
It's very easy to imagine a plasmid that evolved to encourage production of itself and was likely even beneficial, but eventually came to be so strong as to completely hijack the machinery of any cell that received it, or simply lost its ability to be ejected(but not inject) and would accumulate until host cell death as a result.
Sorry if any details are mistaken, it's been a long time since college.
I personally also think that the existence of at least four different kinds of self-replicating(directly or indirectly) schema(cellular life, viroids, viruses and prions) is ample evidence to believe that different viruses may have originated independently in any number of ways. Some larger viruses having "degenerated" from cellular life doesn't seem too improbable either, for example.
1:32 And sadly, not in a fun candy shell either. :(
Though, in a sense, you *could* say it's a "f***ing shell", as many have misheard it.
very informative content
“Demonetised: reason: current events”
Thankyou!
Very interesting, thank you
Thank you
I'd like to coin the term "stem life" to describe viruses.
Sounds good, once we are sure it's true.
Some plant viruses are arguably mutualistic, triggering benificial biological changes like cold resistance.
Amazing video
When you mentioned the viroids being just a bundle of genetic material, it got me thinking; what if viroids are the result of the RNA escape hypothesis you mentioned earlier? It would still be possible for the viroids to mutate or even start out with a coating too. I find it pretty unlikely that viruses would evolve first, because they wouldn't even have the necessary parts to replicate themselves anyways, even if they're extremely simple.
I'm with you on this. I also think that different viruses can have different origins, so it's possible that every origin theory mentioned in the video is true. Parasitic beings tend to reduce their complexity, and used to be more complex before taking the parasitic path. So the similitudes we see in viruses are only because we are seeing the end result, but different viruses could came from very different organisms.
The hypothesis is that retro viruses evolved first from the first metabolism to evolve, and the possibility of an RNA world. The metabolism happened first followed by cells (archaeal & bacterial.) This appears to have happened quickly (in geological time) so maybe the RNA elements could also have had to form a capsule to invade cells. Unfortunately for the hypothesis todays bacteriophages are DNA based, not RNA or even retro-viruses.
How do you know if the shared viral DNA between species is due to a common ancestor vs due to a virus that can infect both species?
since each time virus infects other cells and in case of ERVs they nest themselves in unique place after each infection. By this having ERVs in 2 different species implies a common ancestor that got this retrovirus and its remnants were passed down further. The probability that the retrovirus nested itself a few times in the exact same places is highly unlikely. What's more some of these ERVs are mutated in the same way, making it even more unlikely to happen separately.
"this phenomena"
Man, this videos must have taken a keen eyes to proofread.
Spillover by David Quammen is worth reading if you enjoyed this excellent and fascinating video✨
Viruses be like: ayo ima just be so parasitic that I need a different organism to live on
Nature is horrifyingly beautiful.
We would consider other parasite's alive, so I would be leaning towards virus's being alive but also similar to a hybrid of spore's/plant pollen etc. Sorta like a genetic seed spore.
Obligate Intracellular Parasites.
I think there are very good reasons for classifying them as alive.
Short version: scientists still don't know how viruses evolved.
So if it’s basically some RNA and protein around it, how does it die if it’s just left out in the open for a few days? Does it dry out or something?
Yeah, just basic wear and tear.
@Limey Lassen how does something that small get worn and torn though?
@@dougthedonkey1805 UV light and oxygen, mainly. Same reason paint fades and metal rusts.
@Limey Lassen I see, thanks!
Bacteriophages look like sentient living creatures 🙃
If life can be that small, I wonder how large it can be.
The volatile environment of early earth would be highly detrimental to RNA and its simplicity . What evolutionary pressures would allow them to evoke and what hosts did they initially infect?
I don’t envy geneticists. I’m a neurology student. I literally study the most complex machine in the universe and one of the least understood fields of science, and I think their job is still far more confusing.
I done care
I just wanna point out that, simply do to their structure, bacteriophages are one of the scariest things in nature to me
Viruses are like the microscopic equivalent of the uncanny valley
Make a video explaining the difference between a virus and a bacteria please!
The difference is actually pretty simple, bacteria have the parts and proteins to replicate themselves, while viruses don't.
He just explained it, bacteria are alive and have the proteins and things that it needs to procreate, while viruses are not alive and don't have the proteins and things it need to procreate by itself.
Life is chemistry, no line to blur.
But Not all chemistry is life
War of the Worlds made me realize how terrifying viruses and bacteria are.
how are viroids chemically stabilized?
Just because two animals are infected by the same virus doesn't mean that the virus infected their common ancestors - viruses often jump between species.
Viruses aren't all pathogens. Even some of those which are, ie phages, help people. But beyond that, some think that the nuclei of eukaryotic cells derive from viruses, and it's likely that placentas evolved with the aid of a virus. To name but a few viral effects positive for all eukaryotes and for us placental mammals.
Generally, I like your educational videos. But the lack of overall structure (absence of course design) and the monotone delivery make it hard to see how the parts and videos fit together. Because of other production values, you may still generate a lot of views.
If viruses are indeed living creatures does that mean that LUCA isn't universal? Or are viruses related to something?
Not all viruses are parasitic. You could say that WO, a bacteriophage to Wolbachia, is mutualistic, not parasitic.
hang on, can you rule out bromoviridae entering humans and marmosets at different times? You said "very similar".
R and a sounds like a music genre
My hypothesis: viruses are an alien experiment.
نُورٌ عَلَى نُورٍ يَهْدِي اللَّهُ لِنُورِهِ مَنْ يَشَاءُ
I will never understand people who say viruses are not alive
bangin
Damn it hate how this is relative now
I think since most organisms became smaller, so are they.
Could it be, that the blind watchmaker got lucky and out of pure Randomnes some aminoacids formed some kind of Viroid, that got attached to a multicell organism, wich enabled its survival in the first place, if it didn't reduced the fitness for survival?
Man, I love your videos so much,
they always teach me something new and interesting 💪💪👍👍🔥🔥
Y'all should level up and hire an animator!
So this distills theory down to whether or not DNA/RNA existed autonomously before cellular formations and possible caused cellular formations or; Cellular formations occurred before/simultaneously and acted as micro-segregating environments for autonomous DNA/RNA or autonomous proteins that became RNA/DNA, thus forming RNA/DNA. OR perhaps its somewhere in between....
perhaps abundant early uranium leeched radiation through marine vents, where chemically derived organic proteins that had settled near the bottom, would be churned upwards towards surface waters. Random congealment of the proteins (like snowflake formations) forming proto DNA and RNA, while creating connective lipid congealment's as a by-product. the inevitable trapping of congealed proteins within proto cellular lipid structures, would be continually exposed to intense radiation upon each churning upward lift, damaging proto-RNA/DNA structures within those proto-cells at random until only the most rigid radiation resistant formation (real proto-RNA/DNA) was left behind in non-reproducing proto-cells. These resilient proto-cell structures would naturally shrink and expand in palpating motions by thermal energy exposure near the vents, making their cell walls penetrable to new RNA/DNA material which would react at random with the internal "well-formed" proto-DNA/RNA. This would eventually cause a proto-cell to expand and "bud off" a mirror image of itself in the first act of "Thermal energy dependent proto-cellular replication". This would explain how advanced RNA/and DNA could form from radiation, and how the resultant "phenomena of life" is dependent on an energy input for reproduction. Its also a fairly simple process, which would automatically occur once surface oceans form, explaining why life seemingly "immediately arises" after earths cooling began. It might insinuate that all earth-like planets would have this happen and that the "phenomena of life" is always convergent in basic micro-design.
They are smart ....................... Q: can a virus live in a host forever without killing it ?
The fact that the virus is made up of protein tells you something about when it evolved. It did NOT evolve before cells. Why? Because proteins do NOT appear out of random chemical processes in Nature. They only get created inside cells. In fact, they are produced in the nucleus. An important fact to keep in mind is that proteins when created in the nucleus don't work! They have to be folded in very precise ways before they are capable of carrying out their intended function. No specific fold no functionality at all. That folding, too, is carried out in the nucleus of the cell. After that, there is a quality assurance stage that allows the properly folded protein to leave the nucleus and go to the cell proper where it will perform its intended function. If the protein fails the Q.A. check it is destroyed!
So, if trillions of years were granted to create a protein randomly in Nature; that would avail nothing as it wouldn't have the folding required to make it functional. Also, as you say, viruses need cells to replicate. So, whatever protein appeared randomly would not be able to replicate and quite quickly would be destroyed by ultraviolet light in the environment!
Now, something that goes on in the creation of human red blood cells may provide a clue to the origin of viruses. The red blood cell in all mammals starts of with a nucleus; but that nucleus for whatever reason is ejected from the cell. This happens in us millions of times every second. www.sydney.edu.au/research/opportunities/opportunities/1165?faculty=11
It may be that whatever started this process, called enucleation, in our far distant past led to the ejection of parts of the nucleus in a form that roughly complies with what we now call a virus. When I say, our, I mean to refer to all mammals. Birds, reptiles, amphibians and fish do not enucleate.
Another curious thing about red cells, called erythrocytes, is they don't possess organelles such as the mitochondria. The process that purged them from mammalian cells long ago (assuming they were purged) may have dumped them out as incomplete protein chains which acted like modern day viruses (i.e. reentered the cell and replicated with the help of the cell).