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Are Viruses Alive? - with Carl Zimmer 

The Royal Institution
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Are viruses alive or are they lifeless packages of protein and nucleic acid?
Watch the Q&A: • Q&A: Are Viruses Alive...
Carl's book "Life's Edge: The Search for What It Means to Be Alive" is available now - geni.us/zimmer
Countless scientists around the world study life, and yet they can't really agree on what it is. Join New York Times columnist Carl Zimmer as he explores the boundaries of life, encountering viruses and other strange residents of the borderlands.
Carl Zimmer is the author of fourteen books about science. Zimmer’s column "Matter" appears each week in the New York Times. His writing has earned a number of awards, including the Stephen Jay Gould Prize, awarded by the Society for the Study of Evolution. His book, She Has Her Mother’s Laugh, won the 2019 National Academies Communication Award. The Guardian named it the best science book of 2018.
Zimmer is a familiar voice on radio programs such as Radiolab and professor adjunct at Yale University. He is, to his knowledge, the only writer after whom both a species of tapeworm and an asteroid have been named.
This talk was recorded on 26 August 2021.
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24 ноя 2021

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Комментарии : 2,2 тыс.   
@markniblack7160
@markniblack7160 2 года назад
As a physician, I have to say that I think this was a brilliant presentation! As I was in medical school in the 70's, and haven't studied viruses since then, I was amazed at the depth and breadth of new information, and the clarity of his explanations!
@cheapmovies25
@cheapmovies25 2 года назад
It's a whole new age now...
@brianeaton3734
@brianeaton3734 2 года назад
As someone who is not a physician, I think this was a brilliant presentation.
@trevorjameson3213
@trevorjameson3213 2 года назад
​@@brianeaton3734 Some of it is, but some of what he is saying is absolutely absurd. For example, the demonstration of the fused cells of the placenta, being mandatory for the survival of the fetus, and therefore REQUIRED for human reproduction (that much is true). But then he says the genes for the molecules responsible for the required fusion of the placenta cells are from a virus, and that quote "None of us would be here without those viral genes".. Ok, so if that is true, how did the virus infect a human that isn't there to begin with? Since we wouldn't be here without those viral genes to begin with?
@bertramlee880
@bertramlee880 2 года назад
@@trevorjameson3213 Sort of like asking if chickens come from eggs laid by chickens where did the egg come from before there was a chicken to lay it. It came from a chicken ancestor, The virus infected some ancestor(s) of placenta mammals.
@marvahuff635
@marvahuff635 2 года назад
@@cheapmovies25 As complicated as all this talk of Viruses is, I wonder, if maybe children should be learning this information by junior high school or even before. I studied for years to learn about them and yet in school, there is so few courses teaching what I believe our new world needs to know. If they are in us all than some of us must be in an adaptation mode right now,no matter what our age or? We will cease to exist? Yet we are still here, so why? We must be adapting to these. The people that die? Maybe, just maybe their body can not adapt quickly enough or maybe not at all. I am on Facebook. Care yo comment. I would very much like to hear from you but hope you have some background in this. It is pretty deep, mind blowing stuff. I wondered for years if viruses that land on us like a rocket ship are alive? Till now a window has opened for me, thanks to Carl and his various explanations. Much study may come up with better ways to travel in space. Possibly Robots to the stars injected with RNA altered to protect them? If we can’t go? Or other ways of getting there. Could be the aliens are now studying us for just such reasons, so they can reach further into space. See the Movie War Of The Worlds, either one if you wonder what killed the aliens anyway. Bye for now. Look for the cat in the window. That is me. Always Marva or Marva Huff. 🙋🎆. P. S. Have a Wonderful Holiday!
@ryancounts8131
@ryancounts8131 2 года назад
Carl, this is one of the best presentations I've seen from the RI channel. Thank you.
@korswe
@korswe 2 года назад
I agree 100%.
@jonathansturm4163
@jonathansturm4163 2 года назад
What a delightful lecture! I haven’t been as enthralled since hearing Stephen Jay Gould lecture in Australia many years ago. I look forward to reading your book with relish.
@rh7686
@rh7686 2 года назад
Thanks Mr Zimmer. Great exposition on the incredible complexity and beauty of life.
@robglenn4844
@robglenn4844 2 года назад
The Q&A link in the description seems to lead to the wrond video. It sent me to a video of a panel discussing how well the UK presented pandemic information. Edit: I see it's been fixed, it now leads to the actual Q&A.
@kimberlycitizenenichols5627
@kimberlycitizenenichols5627 2 года назад
Funny how you mention any virus and it is explained somehow with current pandemic info
@auditamplifier8493
@auditamplifier8493 2 года назад
It happens to be killing a whole lot of people right now going on two years running... it's defined our times in major ways and not the least bit surprising to find mentioned in ANY conversation about viruses since its inception...
@FelipeSantos-nc9wh
@FelipeSantos-nc9wh 2 года назад
- Are viruses alive? - Well, it's complicated... - So you don't know, right? - Don't tease me...
@mozzerianmisanthrope406
@mozzerianmisanthrope406 2 года назад
Much like many subjects it's a matter of interpretation. Very intriguing and fascinating topic. Great channel which is full of a plethora of interesting videos. Acquiring every one of Zimmer’s books now! ✌
@marcmetcalfe1820
@marcmetcalfe1820 2 года назад
As a complete layman this is the best explanation I've heard. So well presented. Thank you 🙂
@Rienck
@Rienck 2 года назад
One of the most question triggering presentations I saw in my life! Thanks so much!
@philjamieson5572
@philjamieson5572 2 года назад
I'm going to buy this chap's book. Everything is explained so well in this film. Thanks for putting this on here.
@1089S
@1089S 2 года назад
A Planet of Viruses - third edition . #1 Best Seller.
@fontende
@fontende 2 года назад
Kurzgesagt explanation is better, buy their calendar with more precise history age, which abandoned by all religions because they may become less important and not so fundamental
@irismiranda1225
@irismiranda1225 2 года назад
I am so glad for this video. Each minute was gold. Everything was explain as simple as it could.
@helenpawlirzyn4492
@helenpawlirzyn4492 2 года назад
wow. your video popped up on my youtube homepage and i really wasn't expecting to sit through the entire video. well, i did watch your entire video and was thrilled to have something to actually THINK about and debate. thank you.
@samanthaclaire888
@samanthaclaire888 2 года назад
Thank you so much for this fascinating talk !
@CAM-fq8lv
@CAM-fq8lv 2 года назад
I really learned a lot from this lecture.
@modern_eel
@modern_eel 2 года назад
This lecture has put me firmly on the side of viruses as definitively alive. If we think of the isolated virus as a seed, and not the adult virus, then it becomes clear that just as a maple seed outside of the ground cannot sprout or reproduce or any of the things we understand as life then a virus-seed outside of a cell will obviously not "sprout" or "reproduce". A virus is more like a plant than like bacteria. A virus is dependent on fertile soil (a cell) to become itself, and expecting the seed of the virus in isolation to demonstrate all the aspects of life is as preposterous as expecting a grain of rice in a jar to spontaneously reproduce, collect energy, and all this.
@dnaak
@dnaak 2 года назад
Your thoughts are compelling. Thank you for sharing.
@Euruzilys
@Euruzilys 2 года назад
I agree, however where does this put prion?
@modern_eel
@modern_eel 2 года назад
@@Euruzilys I admit, I'm only Wikipedia informed on prions. But they seem to be a separate case. Although we "vaccinate" for prions, that language just indicates that we can teach the immune system to recognize these dysfunctional proteins. I imagine the language of "replication" is also misguiding with prions. My cursory readings suggest this disease is something of a crystallization event, where proteins in a stable arrangement like to pull other proteins into the same arrangement. It would make sense that if that a crystalline-ready protein is in a favorable environment, it would continue its formation, and in that way imitates "transmission" and "infection". The main thing for prions is that they appear to have no DNA/RNA, and its progression happens extra-cellularly., which reads more like a purely chemical issue than anything else.
@modern_eel
@modern_eel 2 года назад
@Scott Beck Thanks for the additional sources, i will check it out.
@nissimhadar
@nissimhadar 2 года назад
@Scott Beck Who ties your shoe-laces? Hmmmm ... .where you are, do you even have shoe-laces??
@001Cherith
@001Cherith 2 года назад
even I can understand more than half of the talk, great job! Thank you.
@criticalthinker8007
@criticalthinker8007 2 года назад
Interesting and informative. I agree the question is non sensical because it depends on your definition, but beyond that virus are fundamental.
@clemguitarechal
@clemguitarechal 2 года назад
Thank you Mr. Zimmer and Royal Institution for this very instructive journey about viruses, and where we are as of today. Clearly the question is complex, and I can't wait to hear more about it in the next decades, just as Mr. Zimmer said. This question may seem simple, but indeed the legacy of viruses over life itself, as we know it, goes so deep that it would be such a waste not to look for a clear scientifical answer to it. The subject is connected to so many other questions and fields, other than just microbiology or virology ! Cheers "Ri" ! Love you guys, the content you deliver has always been of incredible quality ! We're lucky to have you on RU-vid, so accessible.
@brontehauptmann4217
@brontehauptmann4217 2 года назад
there are no coming decades you (we) don't even have one decade left
@brontehauptmann4217
@brontehauptmann4217 2 года назад
@just another human Everything that has been hidden will be exposed.
@AlexEscalante
@AlexEscalante 2 года назад
Incredibly eye opening. Great exposition. Thanks a lot!
@zoltantripsanszky3285
@zoltantripsanszky3285 2 года назад
Just a supplement: Dmitri Ivanovsky was the first who performed that experiment with filters and who found that the remained liquid - which could not contain bacteria anymore - stood infectious. Beijerinck repeated Ivankovsky's experiment 6 yrs later.
@jeffsnow7547
@jeffsnow7547 2 года назад
Heads up, RI RU-vid -- you've got the wrong Q&A linked in this description. Link goes to: "Q&A: How Well Has the Science of the Pandemic Been Presented?" instead of Carl's Q&A.
@dnaak
@dnaak 2 года назад
What a fantastic presentation. Thank you Mr. Zimmer.
@dnaak
@dnaak 2 года назад
​@Scott Beck I did look it up. Not compelling at all as far as I'm concerned. Thanks for sharing though.
@Junkitup
@Junkitup 2 года назад
Thank you, Your effort to make it understandable was appreciated , Thank you
@shamtradtam3769
@shamtradtam3769 2 года назад
Great presentation. As a layman when it comes to microbiology, I was able to totally follow everything the scientist said
@warshipsdd-2142
@warshipsdd-2142 2 года назад
Excellent presentation and I look forward to reading your book. Defining terms both offers the ability to discuss and to limit the scope of a discussion. Too many professionals get hung up on their meaning for a term as well and lose the most import tool of human thought--an open mind.
@raystanton7898
@raystanton7898 2 года назад
Great lecture. I learned a lot. The basic question of whether or not viruses are alive depends on how the word "alive" is defined. I think the main source of the consternation over this question is rooted in mankind's strong predisposition to classify things into finite categories. Not only do our brains seem to be wired this way, but this practice is very useful for communication and for putting a sense of order to our universe. In the real world, though, many things, especially in biology, don't fall neatly into categories. There are shades of gray and transitional properties that fit into more than one category. For instance, most organisms are either clearly plants or clearly animals, but there are some organisms that aren't clearly either one. The classification of species runs into serious problems too. With the "alive or not alive" question, it is pretty apparent that viruses don't neatly fall into either classification. Viruses have properties of both, and I can accept that.
@Observ45er
@Observ45er 2 года назад
Yes. I point out how we put our human values, so to speak, on things. We know how a tennis ball, baseball and marble operate, so when we do a bunch of tests and we see that the electrons and photons act similarly, we view them as tiny little balls or particles. When we do other types of tests, we see that they behave like waves and we know how waves behave. However, it is baffling for one thing to have both characteristics for they are so different. Therefore, our ability to combine those concepts is very limited based upon our everyday experience. Cheers
@raystanton7898
@raystanton7898 2 года назад
@@Observ45er Well said. I agree completely. Our ability to analyze and interpret complex aspects of our world is limited by our main analyzing equipment -the human brain. Our brains evolved for very specific purposes primarily related to survival and preservation of our species. It is not surprising that it has it has difficulties with some more esoteric issues.
@raymondglad5593
@raymondglad5593 2 года назад
There is a group of Dr's and biologist that do not believe this theory. You go back to Antoini Bechamp with the terain theory you find what the powerful pharma builds on falls apart. You can not say to much as it will be censored. There is plenty of alternative theories on alternative video platforms. The world is being lied to.
@ytrebiLeurT
@ytrebiLeurT 2 года назад
So how do you define "alive" ?
@kimberlyjacobsen4148
@kimberlyjacobsen4148 2 года назад
Its a slippey slope. Alive defined one way or the other. If we define it one way, countless other things will be define alive aswell. So how do we handle this? Define anything that sorta does it as the same or not? I’m all for not putting things into boxes but, at some point there is a logical distinction . My opinion is that as long as we agree there are exceptions, we can use the boxy terms. Good comment cheers👍
@adriankolsters
@adriankolsters 2 года назад
Awesome, what a great build-up and explanation. I have some medical background, but this was far better than they ever explained it to me. Thank you.
@jocelynnoyes3893
@jocelynnoyes3893 5 месяцев назад
Great Job on the topic, it was very clear about what a virus is and you really dove into it.
@jamescarthew4553
@jamescarthew4553 2 года назад
Well that just blew my mind. I have always thought of viruses as a packet of protein, lipid and RNA or DNA. I had never considered that an infected cell is also effectively "the" virus. Some bacteria can form inactive spores and they could be considered not alive. That concept is now extended in my mind to viruses. Where the packet of protein, lipid and genetic material are simply the spore phase of the organism.
@stefpix
@stefpix 2 года назад
Yea, but the virocell does not replicate itself. It just hijacked to produce some pieces of rna
@NondescriptMammal
@NondescriptMammal 2 года назад
I suppose when a spore of mold drops on a piece of bread and multiplies itself, the bread is effectively "the mold"? semantic somersaults
@mohant9m
@mohant9m 2 года назад
Amazing presentation from Mr. Zimmer! Ancient Indian Jain philosophers came up with a very simple definition for 'life': if its hungry then it is alive.
@toothybeaver5579
@toothybeaver5579 2 года назад
Lol!
@marthareal8398
@marthareal8398 Год назад
This presentation was most informative. I was not aware of what questions scientists are still struggling. This talk puts it in perspective. Thank you.
@JOpethNYC
@JOpethNYC 2 года назад
Just learned a few things from you here that I can now teach my chemistry and physics students. Your book is now on my wishlist. 👨‍🔬
@timsmith6675
@timsmith6675 2 года назад
Great lecture as always @The Royal Institution and @Carl Zimmer. Most people don't understand the complexity of biology, so good information for all. Best wishes for all in 2022!
@davidthurman3963
@davidthurman3963 2 года назад
Anyone who has been in a personal relationship knows the complexity of biology.
@lucian6172
@lucian6172 2 года назад
He just participates in illegal DNA scams and coverups. Go check how many assassinations you have in the healthcare system using DNA scams from engineered viruses and how they always report that they can't detect any viruses in your system at all. It's all a scam. A very secretly organized scam.
@brontehauptmann4217
@brontehauptmann4217 2 года назад
and others DO.
@lucian6172
@lucian6172 2 года назад
@@brontehauptmann4217 Others do what ?
@cablebrain9691
@cablebrain9691 2 года назад
@@brontehauptmann4217 Obviously; he has already indicated that by using the word, "most." What's your point?
@zapazap
@zapazap 2 года назад
What does it _mean_ to _say_ that a virus is alive? What is the language game that is being played when we say that a virus is alive, or say that a virus is not alive, or ask whether it is alive?
@eeemotion
@eeemotion 2 года назад
See Rupert Shekdrake on 10 dogmas of science, etc.
@AlbertCanil
@AlbertCanil 2 года назад
Thank you so much for such a brilliant presentation.
@Tocsin-Bang
@Tocsin-Bang 2 года назад
Fabulous presentation and explanation. Before I moved into education I spent five years in a veterinary research laboratory that studied all forms of microbes, in my case chiefly acid-fast bacteria and mycoplasma.
@rockets4kids
@rockets4kids 2 года назад
The answer depends on how you define life. Defining life is the difficult part.
@justadam1917
@justadam1917 2 года назад
Very much agree just had this discussion
@jayizzett
@jayizzett 2 года назад
Alive and life are very different
@rockets4kids
@rockets4kids 2 года назад
@@justadam1917 One of the more interesting definitions of life I have come across is "an active participant in the biosphere." With this definition viruses are most definitely alive.
@yanikkunitsin1466
@yanikkunitsin1466 2 года назад
any definition would be not difficult but entirely arbitrary and thus the answer to the question. Like "species" it's an artificial construct/category that doesn't help with understanding the phenomena at all.
@niyui8
@niyui8 2 года назад
@@rockets4kids then you have to define biosphere.
@m.syassin5774
@m.syassin5774 2 года назад
A very useful lecture . Thank you very much .
@samu463
@samu463 2 года назад
Great video, i think it would probably be good to also talk about retrotransposons, for further insight into how viruses came to be and why this further blurs the line of what's alive.
@syork4284
@syork4284 2 года назад
Great explanation of what viruses are and how they function. Very esoteric for a non-scientist, but fascinating none the less. Thanks for making this video!
@pablojr4999
@pablojr4999 2 года назад
This reminded me of a Star Trek episode when they find a living alien that does not fit their definition of life. Our "standard" definition of life seems to put a great weight in those individuals who are similar to us... The closer the individuals are to us, the "more alive" they are.
@apolloreinard7737
@apolloreinard7737 2 года назад
I remember the episode with the Horta, a creature which tunneled through rock and looked a bit like a massive limpet. In that one it was more the question of 'intelligent' life. In the episode, the miners eventually came around and learned to cooperate with their new friends. Win-win, in galactic space.. I'm all for that! :)
@simonxag
@simonxag 2 года назад
Given the need for lucky viruses to create placental mammals, you've got to wonder where all the humanoid aliens come from. Science fiction hasn't really helped our understanding of aliens (humans in funny suits), robots (humans in funny suits) and AI (human characters in a metal box).
@brontehauptmann4217
@brontehauptmann4217 2 года назад
good work blur the distinction between life and non-life. Create confusion and mess with everyone's mind. You are evil.
@natsukashiiohayo1150
@natsukashiiohayo1150 2 года назад
@@brontehauptmann4217 Who is this evil entity you "spake" of? Who defined between life and non-life? Humans. And subject to change.
@LendallPitts
@LendallPitts 2 года назад
Read the book "His Master's Voice" by Stanislaw Lem, who also wrote Solaris.
@danahansen5427
@danahansen5427 2 года назад
In a sense, 'A chicken is the egg's way of making another egg.'
@sooryanarayanan4273
@sooryanarayanan4273 2 года назад
thanks for the talk, informed a lot.
@shmookins
@shmookins 2 года назад
I learned so much in just the first 2 minutes. Wonderful talk. Tank you. That 65 galaxies part blew my mind and I had to stop the video for a bit to gather my brain matter.
@nelsongilbert1695
@nelsongilbert1695 2 года назад
Fascinating and perplexing. Viruses appear to be miniature photocopiers with "different color combinations and excellent lock picking skills"
@msheart2
@msheart2 2 года назад
Oh please do direct me, link me to real photography of viruses, not cgi not exosomes.
@carlalakins
@carlalakins 2 года назад
@@msheart2 …… I read it as a sarcastic comment.
@cardboardhero9950
@cardboardhero9950 2 года назад
i think schrodingers definition of life as systems that fight against increasing entropy holds an inkling to the truth
@misskim52
@misskim52 2 года назад
Yup
@jaybingham3711
@jaybingham3711 2 года назад
From a small seed, a crystal can continually grow...layer after layer...year after year...all the while flipping the bird to entropy. Hence planets, stars and even black holes are alive.
@cardboardhero9950
@cardboardhero9950 2 года назад
@@jaybingham3711 not an expert but i'm pretty sure stars' and blackholes' entropy increases. In the case of stars, as they expand they occupy more space and hence have more microscopic configurations. Black holes increase their surface area, which is a direct measurement of their entropy. Unlike stars or blackholes, living organisms tend to stick to a particular configuration, as our DNA would suggest, in a sort of equilibrium, hence not increasing in entropy.
@therationalist234
@therationalist234 2 года назад
It seems like the answer boils down to the definition of life itself. Thanks for posting this awesome content! I had no idea viruses were that plentiful
@rlpsychology
@rlpsychology 2 года назад
Very, very comprehensible presentation; thanks so much.
@killianoshaughnessy1174
@killianoshaughnessy1174 2 года назад
This presentation got me thinking: Is sentience a trait given to us from an ancient virus?
@AWildBard
@AWildBard 2 года назад
Wow, my mind was blown! When I was young, I learned that our bodies are made of many cells. Much later, I learned that many bacteria are living in our bodies. Today I learned that many viruses are living in our bodies. Maybe the concept of "self-contained" does not really apply to any life. How many of us can exist outside of our biosphere? We live in a niche, and so do viruses. One of the main things this talk made me think of is, how are viruses related to the beginnings of life on Earth? The concept is that somehow chemical reactions let to an organization that became more complicated and started replicating. Are viruses somehow the "atom" of life? One of the most basic and fundamental building blocks??? Could life even exist without viruses? It sounds like maybe the answer is no.
@NightFlight1973
@NightFlight1973 2 года назад
Agreed. Having the same thoughts here. To me, It looks like the simple RNA guided structures could be the primordial kickstarter. However it still begs the chicken and egg issue, but that is just a limitation of perspective with us now being on this end of the time scale.
@mattchagnon5620
@mattchagnon5620 2 года назад
The point about how high the stack would be is absolutely mind blowing.
@stephensomersify
@stephensomersify 2 года назад
Very Very eye opening - THANK YOU - SS, UK
@ordinarryalien
@ordinarryalien 2 года назад
6:49 "You can't make people into crystals." My dreams are shattered...
@CompetitionChris
@CompetitionChris 2 года назад
Only crystals shatter... 😔
@jasko13055
@jasko13055 2 года назад
@@CompetitionChris if dreams ain't alive, then they can be crystallised too
@dahawk8574
@dahawk8574 2 года назад
This guy has never watched Star Trek, obviously.
@ps.2
@ps.2 2 года назад
A shame about Lot's wife, too.
@glenn-younger
@glenn-younger 2 года назад
Great lecture. Thank you!
@zebj16
@zebj16 2 года назад
Incredibly interesting talk. Kind of knew viruses were on the division between living and dead but this put it on a whole new level. Thank you.
@lepidoptera9337
@lepidoptera9337 2 года назад
A stone is dead. It doesn't reproduce and it doesn't adapt. A virus does both. It's not at all like a stone.
@AnyMotoUSA
@AnyMotoUSA 2 года назад
@@lepidoptera9337 some stones do, and even move. As a chemical process, by growth, division, then spalling.
@lepidoptera9337
@lepidoptera9337 2 года назад
@@AnyMotoUSA Fair enough. We might even be looking at one of the chemical foundations for the development of the first chemical replicators there.
@AnyMotoUSA
@AnyMotoUSA 2 года назад
@@lepidoptera9337 no, I think its more or less just a fundamental question as to how we view what life is. I think the constraints of our cataloging process keeps our minds open to possibility but the correct conclusion may be more complicated. Take agency for example. A single called organism has a fair amount of agency, as to where is may find food or have responses to its environment, actively and with seeming choice at the expense of other organisms in its environment. Does that mean that a chemical process has agency over its environment, such as in crystallization or ion pathway processes? Not sure attempting such a refinement of what life means can possibly come up with an answer. Another example may be prion replication. As you may know, prion proteins are free radical chains of protein strands that replicate on their own without any intervention from processes of division and reproduction and survive simply by adding to the chain and breaking free to form more individual clusters of prions, thus exponentially replicating until organism death. But I dint think that prions are alive, or have agency. Very complicated subject.
@voltaire975
@voltaire975 2 года назад
Thank you Mr. Zimmer. We have a whole new world the think about. Thanks also to the Royal Institution.
@brontehauptmann4217
@brontehauptmann4217 2 года назад
yes you do but you are miles off in identifying that new world
@purplepeace2188
@purplepeace2188 2 года назад
What a brilliant lecture. This reminded me why I loved biology at school and college many decades ago.
@JaquelineVanek
@JaquelineVanek 2 года назад
brilliant???
@MICKEYISLOWD
@MICKEYISLOWD 2 года назад
You should of gone into biology for a career. It's such an interesting field these days with so many research areas. I am fascinated with Astrobiology.
@bubblezovlove7213
@bubblezovlove7213 2 года назад
@@JaquelineVanek Interesting, accessable, insightful and in depth = brilliant. 😎
@horsetuna
@horsetuna 2 года назад
Very educational and enjoyable. I like that you presented both sides and did not make any definite assertions either way, leaving it up to people to decide for themselves. Very factual, and you also give references so people can research themselves.
@user-gh2uz2ix2o
@user-gh2uz2ix2o 2 года назад
Brilliant presentation! Thanks for that.
@zephodbeetlebrox3670
@zephodbeetlebrox3670 2 года назад
Fascinating. Brilliant presentation.
@rmutter
@rmutter 2 года назад
A fascinating and clever presentation. Thank you. Having toyed with the aforementioned definitions of "alive" my question is: are societal cellular level congregates alive?
@lifecloud2
@lifecloud2 2 года назад
r mutter ... I would say "yes" ... it's a matter of cooperation and there's got to be impetus for this, IMO
@markmartens
@markmartens 2 года назад
"We have a feeling that life is different from other things. So we ask...'what is life'?...there's not really a good agreed on answer yet, to that question. There's no standard definition of life, which is kind of weird. Imagine chemists, for example, not having an agreed on definition of an electron. Or of hydrogen. Yet somehow biologists manage to do lots of important work without actually agreeing on what it is that they're studying."
@deusexaethera
@deusexaethera 2 года назад
The important point is not whether viruses are alive, but that the existence of viruses demonstrates there isn't a clear separation between living and non-living. That ambiguity is essential for the concept of abiogenesis to be possible without a pre-existing intelligent creator. For life to arise spontaneously, it needs to be possible for combinations of molecular machines to produce some of the characteristics of life, but not all of them, increasing in complexity until all of the characteristics of life are achieved. Indeed, the process of abiogenesis may not be complete even now. For all we know, billions of years from now, our own definition of "life" could be seen as incomplete compared to what organisms at that time are capable of.
@bmares1986
@bmares1986 2 года назад
If it wasn't aske so far, I would love to ask your opinion on Schroedinger's What is life? and if you think "life" as a driving force that strives for complexity rather than entropy, or in a way "not non-life" is an accurate description to determine this phenomena? Thank you for the presentation, I wasn't blown away by one since some time like this.
@SoundblasterTonks
@SoundblasterTonks 2 года назад
Excellent talk, thanks! I think the definition of life which Carl presents - a chemical system which can reproduce and is subject to evolution - is useful from a scientific viewpoint e.g. if you wanted to determine if a process found on another world was life or not. It's a science-based definition, so it tries to be objective and remove the observer, the self, from the question. When a lay-person poses the question, "what is alive?", they generally want to know what differentiates themselves from an inanimate object such as a book or a table. From this perspective, reproduction with evolution is merely the mechanism by which the complex wobbly blobs which we call people have been assembled from the elements available in this universe. A person who is biologically unable to reproduce for some reason is just as alive as someone who has ten children, even though the former can no longer participate in evolution. The same would be true for a single cell which has a mutation that prevents it splitting in two but which otherwise behaves just as a normal cell.
@cykeok3525
@cykeok3525 2 года назад
I don't think that that definition breaks down if we look at a sterile individual. Even if that particular individual was unable to reproduce, it is still an example of a set of similar individuals who are able to reproduce Also, we'd still have to consider how the person or unicellular organism came into being: it came into being through that method of reproduction.
@VeganAtheistWeirdo
@VeganAtheistWeirdo 2 года назад
@@cykeok3525 Yes, how something came into being itself is definitely part of the information I would use for a definition of "life." Something that exists through its own evolved symbiotic or parasitic reproductive process is still reproducing, it just isn't capable of self-sustaining, so to me the angle would be "the _use of cellular reproduction_ whether internalized or through parasitic or infectious mechanism."
@Bob-of-Zoid
@Bob-of-Zoid 2 года назад
A person who cannot reproduce is participating in evolution big time! As a host for billions of microorganisms! Those little critters are having huge rave parties in every nook and cranny of our bodies!
@fjccommish
@fjccommish 2 года назад
What do you mean by evolution?
@jasonmachula1472
@jasonmachula1472 2 года назад
@@cykeok3525 Then interpret 'system' as a population rather than an individual.
@mohammedomar4652
@mohammedomar4652 2 года назад
i love the RI lectures - so many , so enjoyable and so enriching
@rinsedpie
@rinsedpie 2 года назад
i share this views
@msheart2
@msheart2 2 года назад
“ Enriching” “improve or enhance the quality... make (someone) wealthy or wealthier .
@laurenth7187
@laurenth7187 2 года назад
I don't.
@Burningquest
@Burningquest 2 года назад
Watched this video the third time. Always fascinating.
@enio17
@enio17 2 года назад
I learned a lot. Thank you!
@MultiCriticalhit
@MultiCriticalhit 2 года назад
Going viral about viruses is probably exactly what we need. Many people still know to little about the topic; viruses. Very informative and a well defined talk, many thanks to RI.
@jmccormick8732
@jmccormick8732 2 года назад
I would like to ask, how are seeds of plants described? Are seeds alive? There are a great many things they can't do until they find themselves in an environment conducive to growth. In many ways this seems to be a similar condition to the Virus. Once a Virus finds its way into a host medium it then becomes something new capable of producing fruit so to speak, these new fruit then go in search of a medium to grow much as a seed would also need to do. Maybe the entity created by the Virus and the host cell is the organism and what we recognize as the Virus really just a seed.
@ViniSocramSaint
@ViniSocramSaint 2 года назад
Almost lost me in the middle but the end is so posh By the way, I guess seeds are considered just a stratum of an organism's lifetime, though it kinda work like a virus it does not really "last forever" when dormant, wakes itself up from the dormant state, and do not get inside another organism to replicate, it grows by itself. We can't say the same about viruses because they are basically encased DNA or RNA. Does basically nothing, when it meets a cell the D-RNA just inserts itself in another's to make it replicate the D-RNA and the casing, and throughout all of this it seems to always be dormant. It does not protect itself, run away, seek prey, digest, metabolise, seek mates, communicate, sense stuff, avoid or seek environments, move... it's just there, then eventually the casing touches a cell's membrane and it plops in.
@shayneoneill1506
@shayneoneill1506 2 года назад
Yes they are. They are incredibly resiliant and t and efficient hey carry all their food inside them. But a seed can die, get old, run out of food, and so on. But at the end of the day, its just a big collection of living cells, just like any other multicellular organism.
@tezzerii
@tezzerii 2 года назад
I don't agree. A seed is capable of growing into a plant which can grow, metabolise, reproduce etc. A virus just triggers a living cell to make copies of the virus which, in themselves, do nothing, like the original virus. If you want to call the virus and cell an "entity", it's really just a hijacked cell which is then killed by the copies, and only the viruses are left, exactly the same as before, just more of them. Seeds produce life, viruses destroy it. And after all, poison can do the same, but does that make it alive? It's the cell that makes new viruses, not the virus.
@amarissimus29
@amarissimus29 2 года назад
No disrespect, but asking this question indicates that you've missed the key point. Viruses are incomplete in a sense; the baggage required for the boring parts of existence aren't there. A seed by definition carries a genome, not bits of one. Parts of our genome are wandering around replicating themselves. They'll exist as long as we do. Same with prions, but on an even lower level. They're part of us, albeit a rogue one, and destructive. But a part of life. If you consider the whole planet as an organism (seeing as we all most likely sprang from a single event) the question of what's alive entirely disappears. Philosophical twiddle... not very useful.
@cmddcd
@cmddcd 2 года назад
It's a manifestation of information.
@Bruno_Haible
@Bruno_Haible 2 года назад
The change of perspective from virus to virocell is so intriguing. It's like if we would attempt to understand a fungus by looking only at its spores - that would be the wrong development stage to look at. Similarly, the perspective of a virus as merely a packaged RNA/DNA meme or as a chain letter appears as insufficient, in hindsight.
@alcyone1349
@alcyone1349 Год назад
Brilliant presentation! Cheers to Carl and the Royal Institute.
@KedgeDragon
@KedgeDragon 2 года назад
As is pointed out, the true answer to the question, "Are viruses alive?" is "What does 'alive' mean?" As is always the case, everything depends on the definition of terms, such that both NASA's hard "no" and Forterre's hard "yes" are absolutely and fundamentally true. It is the chicken-and-egg debate writ small - or large - depending on your definition of "size".
@therealzilch
@therealzilch 2 года назад
Agreed, except the chicken-and-egg debate has a clear answer: the egg came first. The precursors of chickens also had eggs.
@dn1697
@dn1697 2 года назад
​@@therealzilch ... yes ... the egg ... which wasn't a chicken ... but this falls short of understanding where the egg came from ...
@therealzilch
@therealzilch 2 года назад
@@dn1697 Given that evolution is gradual, there's no line where a non- chicken suddenly lays a chicken egg. Thus, eggs come clearly before chickens. As to where eggs come from, they are single cells, in the case of chickens (and humans, etc) fertilized by another single cell. Eggs obviously evolved from cell division in single celled animals, but we don't know the details.
@CH-fc8dm
@CH-fc8dm 2 года назад
Fascinating talk, great stuff thank you
@TheCarlosEMaldonado
@TheCarlosEMaldonado 2 года назад
A wonderful presentation. Very well argued, pros and cons, and fully documented. The crux lies in the implications sketched out. I would like to highjlight the one that is perhaps the most salient: we are on the verge of a new speciation ...
@jjbudinski8486
@jjbudinski8486 2 года назад
Going deeper, where do prions fit into this equation?
@fabiocaetanofigueiredo1353
@fabiocaetanofigueiredo1353 2 года назад
The answer to "what is life?" is whatever one chooses it to be. It is a definition, not a truth...
@artsgonzales
@artsgonzales 2 года назад
True, most , if not all problems/debates/ argumentation/ conflicts, are problems of DEFINITION.
@emmettgrogan4217
@emmettgrogan4217 2 года назад
Much like "Is Pluto a planet?" Pluto doesn't really care what we think. Viruses don't if we consider them life, either.
@pamelaspelbring6297
@pamelaspelbring6297 2 года назад
as a lay person this explanation is awesome. And whether right or wrong I can link viral infections to cancer (new evolution?) ... thank you this is mind boggling
@eriklarsen1599
@eriklarsen1599 2 года назад
This video is very important and informative
@bristolfashion4421
@bristolfashion4421 2 года назад
Thanks ever-so for such a great episode ! I think they're not so much alive, viruses just *are* ... !
@danielhanawalt4998
@danielhanawalt4998 2 года назад
Very interesting stuff. I was wondering during this if we or any life could exist without viruses. And thinking maybe viruses are just a life form we don't understand.
@Enkrod
@Enkrod 2 года назад
We could exist without viruses, but viruses not without us. On the other hand we could not exist without plants, we are very dependent on other life to allow us to live. Viruses only take this further.
@mireyajones810
@mireyajones810 2 года назад
YES, our bodies MAKE proteins, aka viruses, when we are in oxidative stress.
@noelburke6224
@noelburke6224 2 года назад
Viruses are not living cells they are dead matter expelled by the body
@rovidius2006
@rovidius2006 2 года назад
@@noelburke6224 They are control mechanisms used by aliens controlling the planet ,if someone else wanted to control life on earth what better than a virus would that be ? when released they don't stop till they reach all corners of the earth , lots of power vested in it .
@cameron6538
@cameron6538 2 года назад
@@mireyajones810 viruses arent solely proteinaceous
@williamramey1959
@williamramey1959 2 года назад
This was a very stimulating presentation. I personally find a part of the definition of what constitutes life unrealistic, specifically, "self-sustaining." No one in the human race is self-sustaining, otherwise, we would not have to be parasitic and acquire metabolic energy from sources outside ourselves. We acquire our metabolic energy from vegetation and animals. Without absorbing the proper nutrients from these sources, we would cease to exist. Hence, we are not "self-sustaining." We too are parasitic like viruses, but certainly "replicate" in a different fashion (which I am very happy about). However, like viruses, humans replicate in "self-expression" with all the variants. Marvelous!
@noelburke6224
@noelburke6224 2 года назад
This is covered extensively by Dr Sam Bailey who also has a book out called Virus Mania
@tlockerk
@tlockerk 2 года назад
Nice to see EO Wilson won't be forgotten, if only for what he missed.
@gecarter53
@gecarter53 2 года назад
Great presentation! Can someone please clarify something for me: 1. When he mentions there are 10^30 viruses, does that number represent a count of all unique virus types, not the total quantity of all viruses on earth regardless of type? 2.When he says a stack of all viruses would reach 200,000,000 light years, is that a stack where each unique virus is counted once, or stack of all viruses on earth regardless of type? Thanks.
@gunnargervin1275
@gunnargervin1275 2 года назад
1. He refers to what science knows of viruses. 2. All known viruses on earth. (Earth/sea & space explorations might reveal more viruses & other evolving matters.)
@gecarter53
@gecarter53 2 года назад
@@gunnargervin1275 Thanks.
@annoyingbstard9407
@annoyingbstard9407 2 года назад
No. To get an idea of the actual size of a virus if every single SARS CoV 2 virus on the planet were concentrated into a mass it would fit into an egg cup with ease.
@Ai-he1dp
@Ai-he1dp 2 года назад
What an excellent explanation of viruses...and how much we really don't know...how biased OPINIONS in the science community can hamper our understanding and progression in all sciences...thank you Mr Zimmer for your valuable opinion and knowledge.
@dmelkey
@dmelkey 2 года назад
And yes, Thank you Mr. Zimmer. Very educational.
@davideasterling5262
@davideasterling5262 2 года назад
Thank you for a wonderful presentation. I was in Medical school in the 70's and I learned that viruses were thought to have originally been bacteria that somehow lost all of their other parts, in a sort of reverse evolution. It is obvious, I think, that viruses could not have emerged first before they had host cells to use for their own propagation. The certainly are strange compared with other forms of life. How did they evolve?
@emm_arr
@emm_arr 2 года назад
That was a really good lecture. A big thanks from me to Carl Zimmer and the RI.
@jrudy457
@jrudy457 2 года назад
I had a question about 51:45 where he talks about the protein from a viral gene helping fuse cells for the outer layer of the placenta. It seems like the expression of this gene would need to be tightly controlled to ensure that the proteins are only produced in the right cells at the right time. So when our ancestors captured that viral gene, how did they "learn" to control it's expression fast enough to prevent all their cells from creating the protein and trying to fuse?
@FatFilipinoUK
@FatFilipinoUK 2 года назад
I guess it just goes through the same evolutionary process as any other random genetic mutation fixed into DNA. I imagine our ancestors that captured that viral gene were so primitive that they still laid eggs, and the gene was more or less "useless". Over millions of years of evolution, our ancestors gradually ditched the egg and evolved the placenta using this inherited viral gene in their DNA. That's one possible scenario.
@MrGarymola
@MrGarymola 2 года назад
@@FatFilipinoUK ...Macro evolution is a hoax & there is zero evidence that any species has ever evolved into a different species...micro evolution is a different story with clear evidence that a species will adapt to it's environment with changes within this species...thousands of scientists after new discoveries in recent decades have debunked the old worn out macro evolution theory.
@meneeRubieko
@meneeRubieko 2 года назад
FatFilipinoUK guessed the same, could’ve been a dormant gene in the DNA which activated and introduced a different more energy efficient way to latch specific cells together. I know there are multiple ways cells are held together
@JRobbySh
@JRobbySh 2 года назад
@@FatFilipinoUK Human beings have eggs but women do not expel the egg but keep it inside of their bodies rather than exposing it to the environment. Except those women who arrange to have it removed.
@JRobbySh
@JRobbySh 2 года назад
That is where natural selection comes from. But to your point. The probability is low to impossible. But miracles do happen.
@lifecloud2
@lifecloud2 2 года назад
I love that we're stepping back from our usual definition of life and allowing for other "versions" of living things. I've felt this as the case for a long, long time and all I've managed to do with this idea is get into arguments about it. HAHA! There's a very strong belief out there that life requires certain elements to be considered lifeforms. This is a carbon-based life perspective (in my humble and uneducated opinion on the subject). I think we're discover through exploring existences on other planets that this definition of life is very narrow. Once we expand this, I think we'll amaze ourselves. This is a great video! Thank you for this. The book looks interesting. I'll put it in my wish list.
@lifecloud2
@lifecloud2 2 года назад
@Ci Absalon No doubt. 😊
@hanszlh6522
@hanszlh6522 2 года назад
@Ci Absalon - the human-beings sort have had all sorts of different "thought(s)" about Life - and 'Man & God & Law" since their brains started rattling ( - not really all thát long ago !! .. )) , who knows , what future - but NEAR !!! - 'artificial' brains may come-up with , once they go full blast ?? - most likely that 'we - humanoidz' are rather 'superfluous' , if not 'hindering' progress ........
@georgehanson1658
@georgehanson1658 2 года назад
Wow! I'm passing this on in the hope that some curious minds will take a keen interest and help humanity in a positive way.
@charlesbrightman4237
@charlesbrightman4237 2 года назад
Consider the following: Language, the very thing we utilize to think thoughts and convey ideas. Un-named Concepts -> Given a Name (could be a sound, symbol, etc) -> With an attached meaning -> And maybe even other meanings depending upon context -> And maybe even other names with the same meaning. (Basically a Dictionary and a Thesaurus for a language). BUT: a. How exactly do we know for 100% certainty that we have all the un-named concepts that could ever be named? b. How exactly do we know for 100% certainty that the meanings we give named concepts are 100% correct? We truly do not know what we do not know. This is a part of the 'Great Unknown'. Never stop learning.
@rar7631
@rar7631 2 года назад
If the first thing found by a rover on an alien planet were viruses. Would we declare that we have found “life” on another world? Thank you for this lecture. Very interesting.
@hansweichselbaum2534
@hansweichselbaum2534 2 года назад
It would indicate that there are other lifeforms present, or have been around in the past. Viruses on their own wouldn't make sense.
@LendallPitts
@LendallPitts 2 года назад
@@hansweichselbaum2534 However is there are virophages...
@anthonymorales842
@anthonymorales842 2 года назад
the ability create a protein model never cease to amaze me. So complicated
@josephbishara4791
@josephbishara4791 2 года назад
I like Patrick's definition of living matter - _"a complex, evolving form of matter."_ [28:25]
@shamanstarrpeacefully4536
@shamanstarrpeacefully4536 2 года назад
Very interesting. I have a two part question. Since the body always wants more energy, Can a virus use bacteria to create energy in the body? and could viruses offer energy to the body as currency to trade and gain access to use parts of the body?
@gunnargervin1275
@gunnargervin1275 2 года назад
Yes. I recall| that somebody recently claimed to be able to do exactly that. Our body creates electricity & temperature showing energy production.
@gregvondare
@gregvondare 2 года назад
I think nature beat you to it; those little energy units in every cell are called mitochondria.
@epgui
@epgui 2 года назад
As a biochemist, my impression was that the debate was in fact long settled: the answer is that it depends how you define life, and there is more than one reasonable definition, and you pick whichever is clearest and most useful in a given context. There is such a thing as a bad question: asking "are viruses alive" is just as unproductive as asking "what is the meaning of life". If you don't change the question, you can't make progress towards a useful answer.
@NondescriptMammal
@NondescriptMammal 2 года назад
To a certain degree it's a matter of semantics of course... but if we look at the commonly accepted notion of "life", don't all forms of life have in common some sort of autonomous metabolism, some set of metabolic activities and processes with which they sustain their "life"? It seems like the viruses are simply genetic material encapsulated in proteins... they are for all practical purposes inert unless they have the good fortune to encounter a host cell that will cooperate with the instructions encoded in the genetic material and become a factory for replicating the virus. That is when they could maybe be said to spring to life, but yet, even then it is a simple mechanical process in which all of the magic is contained in the fact that the genetic material can hijack the metabolism of the cell to do its bidding in such a specific way.
@epgui
@epgui 2 года назад
@@NondescriptMammal It's a bit more complicated than that. There are examples of other, more complex, life forms that also require a host in order to "live", there are viruses and virus-like extracellular vesicles that are metabolically active (there are even some that contain functional organelles like mitochondria; mitochondria are interesting on their own even in this respect), and even the most complex cells can be reduced to a collection of chemical reactions. I encourage you to delve into this topic, you will find plenty of examples to add to the confusion, no matter where you prefer to draw the line. IMO, there is no clear line that can be drawn without some arbitrary classification.
@NondescriptMammal
@NondescriptMammal 2 года назад
@@epgui That is very interesting, thank you... I can see why a line would have to be drawn, but I don't think it would be totally arbitrary to say, for example, that a self-sustaining metabolism of some kind is a requirement for categorizing an individual entity as "life"
@sternamc919sterna3
@sternamc919sterna3 2 года назад
If a virus is hosted by an embryonic cell is there a possibility of the virus genetic code become a part of the new embryo-individual's genetic code?
@epgui
@epgui 2 года назад
@@sternamc919sterna3 There is always a possibility that this will happen, and in the grand scheme of things it doesn't really matter all that much whether it's an embryonic cell or not. A very large proportion of the human genome comes from what was originally viral genetic material.
@garylewis8068
@garylewis8068 2 года назад
Great presentation. Daniel Dennett offers an interesting life definition by asking what life 'does' ... suggesting that a living thing has to be able 'to capture sufficient energy and materials to fend off its own destruction just long enough to make a decent copy of itself'.
@corgythompy
@corgythompy 2 года назад
Fantastic video. Thanks so much!
@stevemorris270
@stevemorris270 2 года назад
Viruses are so integral with living cells that it seems reasonable to consider them alive. Still it is a definitional question and therefore depending on definition accepted they are or aren't.
@NoobNoobNews
@NoobNoobNews 2 года назад
But they do operate more like small machines, which is a troubling feature. Your computer is capable of doing things far more than any life can and is arguably just as complex. Yet, computers are not alive as of now. Viruses are less complex than any computer, but they do strange things. It is a puzzling question.
@KaiseruSoze
@KaiseruSoze 2 года назад
I agree except I would lean more towards the utility of the word "life" more than it's agreed on "definition". Words are useful fictions that refer to observables. If we can't agree on what a word refers to - it's not very useful - but it can be "good enough". Perfection is the enemy of good. Voltaire.
@nmarbletoe8210
@nmarbletoe8210 2 года назад
I would agree. They are at least "pieces of life" -- and no organism is more than a piece, it seems.
@monad_tcp
@monad_tcp 2 года назад
@@NoobNoobNews "Your computer is capable of doing things far more than any life can and is arguably just as complex. Yet, computers are not alive as of now" The difference is that a virus is tiny. Like 100nm. Our computers are made of transistors which are 5nm. So a computer is actually huge. We just don't have enough computers. "But they do operate more like small machines, which is a troubling feature." Why would that be troubling ? what if life is nothing but a process, that can happen on any complex enough system ? Why do you think wetware is special in any case, its not.
@monad_tcp
@monad_tcp 2 года назад
We are machines, very complex ones.
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