What Was the Ancestor of Everything? (feat. PBS Space Time and It’s Okay To Be Smart)

Check out It’s Okay To Be Smart’s video for more about the origins of life on earth: • Where Did Life Come Fr...
And check out PBS Space Time’s video on the physics of life: • The Physics of Life (f...
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The search for our origins goes back to a single common ancestor -- one that remains shrouded in mystery. It’s the ancestor of everything we know and today scientists call it the last universal common ancestor, or LUCA.
Produced for PBS Digital Studios.
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References:
www.nature.com/articles/nmicr...
www.nytimes.com/2016/07/26/sc...
astrobiology.nasa.gov/news/lo...
microbialcell.com/researcharti...
www.actionbioscience.org/evolu...
we.vub.ac.be/~dglg/Web/Teachin...
www.mdpi.com/2075-1729/7/2/27/htm
link.springer.com/article/10....
www.ncbi.nlm.nih.gov/pmc/arti...
www.ncbi.nlm.nih.gov/pmc/arti...
www.cambridge.org/core/journa...
www.ncbi.nlm.nih.gov/pubmed/1...
www.ncbi.nlm.nih.gov/pubmed/2...
biologydirect.biomedcentral.c...
www.sciencedirect.com/science...
www.saylor.org/content/BIO_Ki...

[@jasonbaker2126]

I'd like to see a video about the redwood family of trees. There are only 3 species left and they have been around since the time of the dinosaurs. The dawn redwood was found in fossil form before it was found alive in China in the 1940's. These trees are screaming for an Eons episode :)

[@Callordin]

OMG yessesssss

[@geostokes8573]

Want!

[@JoeyVol]

No

[@JoeyVol]

Eon-heads. Unite!!

[@jhonfamo8412]

i have not seen one in 40 years

[@douglashanson7489]

@3:45 "... they may have just floated about at random, constantly swapping little snippets of genetic code among themselves..." That sounds like a description of the dormitory at the first university I went to.

[@emilytallent9677]

hilariously underrated comment 👏🏼

[@alvaronavarro4895]

Bruh 😂

[@williamnicholson8133]

Thats not genetic code thats STDs lol

[@lightenergy17]

@@williamnicholson8133 I mean technically that's still genetic code

[@pinkwings8036]

I don’t know what it is, but this episode always moves me. Something about how there are people who dedicate their lives to understanding what connects every thing to have ever lived feels uplifting and inspiring.

[@williamjames6868]

you mean being paid to sit around and IMAGINE what was that can't be proven?

[@williamjames6868]

@tech four9 Imagining things that can not be proven is NOT knowledge... they call that science fiction or fantasy.

[@aortavin8650]

@@williamjames6868 Yep, I'm sure glad people in these fields don't tend to do that. And when they do, it's not published in studies and papers attempting to bring their fantasies into reality, because they can still figure out which is which.

[@justsomegirlwithagodcomple3068]

@@williamjames6868 could you please stop embarrassing yourself ? Lmao 😂

[@0Clewi0]

Then you look at modern politics and lose all that inspiration.

[@cgpcgp3239]

Narrator: After the Big Bang the universe was an energetic structural mess. But that mess pulled itself together. Me contemplating my life choices: There’s still hope.

[@freudsilver3097]

Oh no.

[@Matt-wk3ud]

It's nice to know the universe is that relatable

[@carlosoliveira-rc2xt]

The most recent thinking is that the Big Bang didn't happen. LUCA is just a construct. Pure nonsense!

[@scipioafricanus5871]

But the universe is getting closer together... *10 million years later* It's getting closer together...

[@legalhelp1048]

@@carlosoliveira-rc2xt so what is sense

[@rommaninc]

- Marvel: The most ambitious crossover event in history - PBS:

[@Bimtavdesign]

Victor Roman Flores PBS: hold my beer

[@jamesfarrell8339]

Victor Roman Flores Awesome

[@gyozakeynsianism]

I think you missed a "hold my beer."

[@abelramirez7320]

PBS: "Hold my microscope"

[@Namkify]

"The Most ambitious crossover Event in eons"

[@gawayne1374]

PBS is the best thing that has happened to youtube

[@blakethefoxxo5162]

You don't even have to know anything about this stuff or really even have an interest in this kind of thing to enjoy it! It's incredibly interesting.

[@xarmanhskafragos2516]

3blue1brown tho?

[@thorr18BEM]

I was also partial to them on radio broadcast.

[@donmack3871]

this is the best comment that ever happened to youtube

[@JiveDadson]

You are too young to remember the old Onion channel. I do so miss Clifford Banes.

[@lukaperazich7131]

Can’t believe I found out I fathered everything. This is pretty cool.

[@yurilowell5213]

Nhaaa it's more like they Granddad us

[@Infamous41]

@@yurilowell5213 dont hate

[@yurilowell5213]

@@Infamous41 im not hating I just was saying there older then.just bieng are dad so you need to mind your business

[@exitium1825]

@@yurilowell5213 Go to the hospital, you just had a stroke

[@pilotonthescene]

Your child support bill is dizzying.

[@lucas11723]

Hank: "We couldn't even guess at it until we mastered the science of genomics." *Me, picturing scientists studying gnomes*: "wild"

[@TragoudistrosMPH]

I love that you said LUCA was not the first to have ever lived, but just our common ancestor.

[@vaiapatta8313]

I've always thought that cave blindness would be "advantageous" in the sense that these creatures wouldn't waste resources on eyes and thus have more energy for organs that are useful to them. Also, fewer orifices means fewer chances of infection.

[@elijahmikhail4566]

Vaia Patta I think the point of the original comment is that phrases like "survival of the fittest" are so commonly misunderstood. Many would argue that bat species losing their sight or at least the refinement of their sight is against evolution because they didn't change for the "better." Obviously, you understand how that can be advantageous; but many don't; and it's these people who misunderstand the theory of natural selection who can comfortably disbelieve in it.

[@TragoudistrosMPH]

Vaia Patta that's certainly possible, if they lose their eyes in a positive way. Some still have eyes, but think of blindness : could be eyes, nerves, or brain that result in blindness. All those options might make some or no difference, depending on the mechanism for blindness. In humans, eyes are sensitive, so not having eyes could make someone less cautious about head/facial injuries (hehe sounds silly), and unintended negative consequences can come of that. Philosophy gets weird, but science is better: A class experiment we had was to mate normal drosophila males and blind drosophila males with normal females in normal conditions and darkness. The blind ones made up like 10% of the next generation in light, but in the dark, half kids were blind and half could see. There was no advantage in mating, but the blind had equal chances in the dark. Resources can be a factor, but there are competing factors, so one 2% advantage here might not matter if something unrelated has a 12% advantage elsewhere. So measuring the real vs hypothetical effect is important :) (and interesting)

[@goldenjackal2900]

that's because a lot of people think that evolution is like evolution in pokemons,like evolving to be bigger,stronger,with new abilities etc. but things evolve to fit a environment not to look cool.

[@Lifebforeafter]

Elijah Mikhail When it comes to "survival of the fittest" I have read something about the DNA line trying to survive as opposed to the species.

[@JohnSmith-zf5dd]

For other fellow layman, I recommend this order of view: PBS Space Time -> It's Okay To Be Smart -> PBS Eons. Because in PBS Space Time they first explain the physics possibilities of life that underlay everything. In It's Okay To Be Smart they explain the abiogenesis origin of life from primordial soup. And finally, in PBS Eons they explain LUCA (Last Universal Common Ancestor) that hypothesised as the first living thing on earth. I applaud this collaborative work between It's Okay To Be Smart, PBS Eons, and PBS Space Time. I also hope for another collaborative works in the future.

[@jonnnnniej]

I started with this one being recommended (probably already watched the space time one without realizing the colab, cause I've watched most of those videos) but I will definitely watch in your given order, thanks! Makes it easier for me to understand when it's laid out like that :)

[@humbleevidenceaccepter7712]

If I were to imagine the perfect KZbin Science channel, it would be this. Informative, but doesn't insult my intelligence. Comprehensive, but in about 10-minute blocks. Exciting, but never presented with unnecessary drama. Very well done folks. Very well done.

[@jimmyjumbo2006]

Thank our lucky stars for helpful educational content like this. There's so much ignorance and anti science all over youtube we need all the science we can get.

[@ChristmasLore]

Seems like a real all out war by now, and one it's absolutely imperative to win for evolution of the species to continue.

[@rodrigoborges3876]

SpaceTime and Eons crossover? My two favorite pbs channels!

[@TS1336]

Rodrigo Borges well said!

[@skylar141]

Don't forget It's Okay to be Smart!

[@Vistico93]

(two progenotes collide, merging) PROGENOTE 1: Hey! You got your self-replication in my metabolism! PROGENOTE 2: And you got your metabolism in my self-replication! *life ensues*

[@loganbyrd2024]

Vistico93 funny

[@SynneDennis]

I read this to the tune of Coincidance.

[@yakarotsennin3115]

Hehe great refrence

[@bromicorn]

Better love story than twilight

[@joeeyerman1023]

@@SynneDennis pi

[@josephselkow2845]

Didn't LUCA live on the 2nd floor?

[@ptolemyauletesxii8642]

Bastard! You beat me to it! I was going to say all the scientists are looking in the wrong place. They should be looking on the second floor, and if they'd think back they'd realise they'd seen him before.

[@TempleGuitars]

Upstairs from you.

[@KA55123]

Dame! You got there 1st! You got to be in you 30/40 at least to get this one. Well done!

[@7shinta7]

Great, now I won't get this out of my head for the whole day...

[@mmoore8354]

I think I've seen it before.....

[@TharrisNogaud]

I love my Grand-Luca

[@avariceseven9443]

They have to LUCA lot deeper to find our common ancestor.

[@campkira]

Carbon base life form.

[@SaltySteff]

Oh you

[@amehak1922]

Ugly bags of mostly water

[@amehak1922]

campkira carbon units

[@ALTDOK667]

Argh. >:)

[@NeufeldIan]

The greatest crossover event of all time!

[@Revantaker]

Ian Neufeld hahaha i was looking for this comment!

[@william41017]

There will be an "Eons" video about it

[@sciblastofficial9833]

Avengers Infinity War is the most ambitious crossover event of all time! Me:

[@ObjectsInMotion]

Nah that was when an archea engulfed a prokaryote without consuming it forming the powerhouse of the cell!

[@mobspeak]

The nerdy eclipse.

[@hippiehoni]

3:54 "hey baby, wanna swap some code with me?" - First pick-up line ever, translated from biochemical signals

[@johnnyfavorite1194]

The Ancestor of Everything still exists to this very day. I’m speaking of the unimaginably immense organism or being whose very matter is the Universe Itself and all things contained there within.

[@redwolf7929]

Jonny Favorite so true , and the universe is also studying itself through us homosapiens and other intelligent life contained within .It is ancestor , descendant , teacher , and student. all at the same time.

[@nakenmil]

Could you make a video about when and how vertebrates and arthropods split? This has always fascinated me, given the similarities and differences between the groups.

[@aronchai]

That goes back to the split between deuterostomes and protostomes, which is one of the deepest divisions in the animal family tree. Deuterostomes include vertebrates, sea squirts, echinoderms (that's right, starfish and sea urchins are more closely related to us than insects are) and a few oddballs like acorn worms and pterobranchs. The ancestral deuterostome was probably something like an eyeless, brainless worm, with slits in its pharynx that would eventually become the gills of vertebrates. The protostomes consist of basically all other bilaterally symmetrical animals, meaning mollusks and arthropods as well as annelids (including earthworms), nematodes, and a number of other obscure, mostly wormy-looking phyla. The split probably happened sometime in the precambrian, but when exactly is hard to say.

[@crappyblueangel74]

idk about vertebrates but arthropods do split during moulting

[@phxcppdvlazi]

precious

[@Roboprogs]

aronchai so, Arthropods form mouth first, and vertebrates form butt first. 😁

[@Elizabethbaileysigmar]

AronRa covers that in his phylogeny videos. He is up to episode 30 something. Individuals in these comments are so thorough it is kind of surprising no has mentioned that. It is kind of neat to be able to point to an answer to a question. Most of my good thoughts are already pointed out by other thoughtful individuals.

[@greypaladin4560]

Please do more big question collabs like this. It's cool when different channels create videos on one subject, but instead of being responses/reactions or rehashes of the same thing they are complementing and expanding on each other.

[@aulii11]

I just recently discovered PBS Eons, and you're blowing my mind! I'm loving and sharing your channel - thanks!

[@yvessioui2716]

(Retired biology teacher). I appreciate most that you present science as an ongoing process from aspects more stabilized up to those that are only working hypothesis. It is the most useful aspect of teaching any science and thus the basis to restore 'faith' in scientists and science.

[@SophiaAstatine]

Oh my god. Some of the best people ever in the same video collab!

[@johntate6537]

Now if they could just find a way to shoehorn in a contribution from Three Blue One Brown, we're there: the singularity of nerddome.

[@davidnotonstinnett]

Wait...hank and other hank in one video? With Australian Space-science man? What did I do to deserve this?

[@korpen2858]

Matt the space-science man is Australian tho

[@malvoliomaximillian2001]

"British science men" idk why but this made me laugh

[@Correctrix]

I scrolled down to see an American making an idiotic comment about Matt, the Australian, not being American. My expectations have been exceeded.

[@davidnotonstinnett]

Correctrix hey, it’s hard to tell sometimes. Brady Haran (of numberphile fame) has told stories about how when he goes back to Australia he sometimes gets mistaken for a Brit. The accent goes away fast if you live abroad.

[@hlcepeda]

7:52 That's one fidgety and impatient looking hawk: "C'mon! Get to the POINT! Got things to DO!"

[@JohnMitchellCalif]

PBS Eons animations are incredible! Fun and engaging and always clearly getting to the point.

[@evaangellus]

Living the Vida Luca!

[@josephselkow2845]

hahahahaa

[@frankfahrenheit9537]

No netflix yet. Not to mention internet, or just oxygen.

[@Nz-tm3gs]

no

[@veronicagorosito187]

HAHAHA 😜

[@loudmind68]

Caution with Mr. Comedy, don't kill you with jokes

[@austin4855]

This video collab was incredible. If you're here and haven't watched the other two, please do. The order isn't that important, but the full picture they give together is. It's all so well-presented. I'm partial to PBS Space Time but I especially love Matt's explanation of the statistical "necessity" of life to enforce the second law of thermodynamics.

[@jonbeecee]

4:13 Hank Green and Joe Hanson in the same 10 seconds, I am ELATED

[@zebdawson3687]

3 of my favorite channels coming together! This is awesome!

[@freakenproduction]

Massive props for this huge project. You guys did such an amazing job of fitting all of that in one video.

[@elephantjewls]

This crossover was a great idea. I love seeing different aspects of one subject on their respective channels. You guys should do more of these. I'm sure there are more complex topics like this deserving of multiple videos.

[@n.d8001]

Thank you for trying to educate us with such passion knowledge and clarity

[@PyroTurk]

This is an amazing episode! I got chills and even teared up a little. Thank you everyone at Eons and PBS digital studios!

[@creepervideo1106]

Better crossover than avengers endgame

[@royzhu5735]

Wow the crossover between eucarya and bacteria is almost as cool as this PBS crossover

[@drownsinkoolaid4203]

Roy Zhu eukarya*

[@siyacer]

@@drownsinkoolaid4203 it's spelled eucarya in the video

[@KoneSkirata]

A mega-collab between my three favourite KZbinrs! THAT's life!

[@MariaGarcia-gj5ie]

I love these documentaries! I've always been interested in our origins and ancient history. More please!!

[@venugopal2227]

this channel is really a great attempt to enlighten all those who like to think in terms of science...both of you present your areas of exploration with so much clarity and that too in a language accessible even to the lay people....

[@atoms_dancing]

YAY!!! three of my fav channels together in the same video! *epicness causes rift in space-time continuum and shoots me through a wormhole into the past*

[@shoyuramenoff]

If we survive that, Matt will host a video on the phenomenon.

[@brendarua01]

Elisr Where do I buy a ticket for that ride?

[@joebox9396]

Hay guys how about doing a short episode showing our last common ancestors with multiple other things i.e. apes, marsupials, reptiles, and the one I most want to see, the last common ancestor between vertebrates and arthropods!

[@brendanotoole5871]

THIS

[@CheCheDaWaff]

There's a good book I'd recommend (I think it might be a little old now) called _The_ _ancestor's_ _tale_ , which is essentially this. It starts with humans and goes back through common ancestors all the way to LUCA. Along the way you get to learn about genomics and other parts of biology, geology and Darwinian evolution. edit: seems like you can read this for free in PDF form now. Cool!

[@Danquebec01]

Modus Ponens Oh thank you for mentioning this. I *loved* this book! One of the best books I’ve read in my life. I learned so much from it.

[@Norman92151]

Excellent introduction to the idea of LUCA. Thanks

[@gregthel9673]

You are an exceedingly effective communicator. I really enjoyed this video. Thanks.

[@LouisFlintCeci]

It's great to see my three favorite PBS Digital Studios channels cooperating like this. Seeing the same topic from three different perspectives adds insights and understanding not available from one alone.

[@jonathanbell5561]

LouisFlintCeci agree

[@lloydy272]

I remember touching on some of this in a comment John and Hank read out on their podcast. One of the proudest moments of my life. Great to see a video on these topics so close to my heart.

[@francesmagro5468]

Love this stuff. Thanks for making it all so easy to understand!

[@bluejack644]

I've seen so many great programs on PBS. I started watching about 49 years ago with Seaseme Street and i ended up here today. It's been a fun ride. So many great programs on Science and Nature, great musical performances, great movies like the Hugh Glass story (the original Revenant.) Masterpiece Theater, Edward Gorey's; Mystery! Great stuff.

[@somecadejos6543]

This is the most interesting thing I’ve seen in a while. Thank you for teaching me something new again! I hope to learn as much as I can about the origins of life of Earth and you guys teach me a lot everyday!

[@niaschimnoski882]

Goku would beat Superman (Just being random)

[@kylebroflovski6382]

Ian Schimnoski Maybe true, but one punch man could beat both of them at the same time with one hand tied behind his back.

[@souparmsbarraza7206]

What about Gyrados?

[@davidozab2753]

"My name is LUCA/I lived a long time ago/I probably metabolized hydrogen and CO2/Or maybe not, nobody knows ..." Ok, I'll stop now.

[@RGSCOTT]

David Ozab ...lol brilliant dude

[@chicobri]

I'm so glad I'm not the only one that had that song running thru his head during this video... thank you!

[@whistlerwade]

David Ozab thanks

[@jamesfarrell8339]

David Ozab Best comment I love it

[@johntate6537]

Now I'm awaiting a PBS Spacetime video on the star Vega.

[@jamesfarrell8339]

I love when different KZbin Creator's come together and in this case they are among my favorites.

[@erfan74ir]

Thanks, EONS, I will share this video with my students. They will learn alot....

[@Ngamotu83]

This is like the Marvel Cinematic Universe, except with KZbin Science channels, and I think we need more of it. ;)

[@DuluthTW]

I love this team-up. Great topic and sound info. Thanks!

[@johnnierah]

Yes, you and your friends do a great job of explaining things everyone should know. I will tell my friends.

[@ishanthmishra7658]

The best collaboration for by the best KZbin channels for one of the most mysterious and interesting topic in Science

[@woltersworld]

YES! I have been waiting for this exact video!!! Thank you!

[@THEH4RLEMSH8KERS]

I

[@woltersworld]

The Harlem Shakers thank you

[@ironsnowflake1076]

I have read and watched other material about the origin of our original ancestor (this was superbly done BTW). I really intuitively believe in the hydrothermal vent as the "cradle" of life theory, it just feels right. This belief gives me hope for the discovery of at least microbial life on some of the icy moons of Jupiter or Saturn.....I hope I live long enough to experience this...so THRILLING TO CONTEMPLATE!

[@sierragamber576]

Found this channel by total accident (hank wasn't on crash course like Im used to) and Ive now binge watched everything here. Not even sorry.

[@paolazo-l4790]

When we look at the world map we can apreciate that most continents and other small pieces of land seem to prefer to point towards the south. Many exemples : south america, south africa, india, central america... but also smaller like florida, italy, greece, california, gibraltar, thailand, kamchatka... is there an significant explanation in the continents derive? This is question I've always asked and nobody seemed ever to know why

[@paolazo-l4790]

Could we have a video about that?, is it relevant enough?

[@jared_bowden]

Huh, I've never noticed that.

[@VeroTesta]

Great collaboration - respect!

[@KerryHallPhD]

It IS so good Hank. Epic collab. Great explanations. As a teenager, I was really moved and inspired by Asimov's "The Wellspings of Life". It is outdated, but the narrative was compelling. I think these channels are amazing replacements to inspire the next generation.

[@monicagorman7352]

Wow, I've just discovered Eons videos and they're great. I love them for me and will show them to students. How about more are on the possibility of life on other planets?

[@shawnweed265]

Absolutely fascinating...and informative...Brilliant!...Thanks.

[@fasjher]

I am loving these overlapping videos. Great work, keep it up 👍

[@stiimuli]

I love these three videos! So much great information

[@danbojtor]

I love how they connected it and I love the topic, but the conclusion... hydrothermal vents? There are plenty of vents around today, yet you don't see living molecules or L.U.K.A.s appear randomly time to time. I call BS on the vents. I hope there will be more videos like these with a little bit more seriousness.

[@stiimuli]

Of course we don't see them popping up...because we're almost never there. These vents were only first discovered in the 70's and are extremely difficult to get to and observe. Primitive life could be popping up all the time around vents but now that there are other, more developed organisms already there they probably would not often survive long enough for us to ever see them.

[@duhduhvesta]

Love this! Love to see more about phylogenetic stuff like this

[@matteofomia3802]

Amazing content. Thank you !

[@psychoactivednb]

All of you are amazing, thanks for keeping my brain happy

[@AlvinLee007]

A collaboration between Hank, Matt & Joe? Keep it together, me! Keep it together! 🌋🌊

[@jamesfarrell8339]

Alvin Lee I love your comment I feel the same way

[@cristianbranea5034]

Wow! Great topic to have a collaboration on! Keep them coming boys, we're here for it!!

[@ronmasters751]

Saw Woese describe his work at a Physics Colloquium in the late ‘70s. Everyone recognized that it was phenomenally significant. Blew me away,

[@smelkus]

One thing I don't understand is how viruses came to be if they require more complex organisms to replicate themselves

[@cocoman290]

William Morgan There are three hypothesis for the origin of viruses. The viruses first hypothesis states that virues are fossils from the RNA world, and that they predate life. This is based on the fact that some viruses have an RNA genome. The main drawback of this hypothesis is precisely the fact that viruses need cells to replicate. The reduction hypothesis states that viruses arose from an extreme parasitic condición. Supposedly they where cells that lost lots of genes until they became viruses. This one relies on the existence of giant viruses that have genomes even larger than those of some parasitic bacteria. Finally, the escape hypothesis (the most likely for me) holds that viruses are escaped genetic elements from the cell, like plásmids or retrotransposons giving rise to retroviruses. Phylogenies of RNA dependent rna polynerases, proteins from the rnaseh family and some capsid proteins support this hypothesis. Annother clear example of this late origin of viruses is the RNA virus distribution which is restricted to eukariotes, the most recent lineage from the three domains of life.

[@cocoman290]

@@SusanKay- CEPI? Forgive my ignorance. Anthropological insights? Actually I am a biologist and I study virus evolution. My research group is about to publish an antiviral drug proposal as treatment against the new coronavirus.

[@mediocreman6715]

Man, this is genious, all 3 videos combined = 40 minutes of "lecture" giving a pretty wholesome idea. A notion that was first introduced to me by a really cool biochemistry professor. Thank you guys so much for the combined insights from such various perspectives. This was a really great and comprehensive summary!

[@claudiomaldonadosalvador591]

So far this is my favorite video on the internet!

[@Egalitariat-likesecretariat]

Oh wow, I didn't know Hank Green was on PBS. I just know him from dimension 20, it's so amazing that he's linked to my favorite childhood channel too!

[@wayneespino9170]

When you realized youre on the good side of the internet! Good video ;)

[@FAMUCHOLLY]

Wow! It's like a three-way super hero crossover!!! Thanks Hank. Ahhh and Joe. And you too Matt!!!

[@alpinestrawberry218]

I love this channel. Feeds the brain hunger for new information with interesting and useful understanding about the world

[@colinellicott9737]

Great trifecta of vids. Thx!

[@0rderofTheWhiteLotus]

Little disappointed that the video didn't approach the topic of viruses and why they can or cant be applicable to be a LUCA-like progenitor. The larger viruses have more kbp than some of the smaller bacteria and theoretically, just as many genes if not more. Viruses are so simple that biologists still debate if they count as a form of 'life' as we currently define it. We are only recently discovering how complex viruses can be, whether RNA based, DNA, single stranded or double. Would love either SciShow or Eons to bring this up and address these differences/similarities.

[@thatonedog819]

There is an argument that they were at least once alive and lost traits to become viruses

[@guifdcanalli]

@@thatonedog819 they ARE alive Just because viruses dont have metabolic apparatus it doesnt mean they are less "alive" They reproduce, evolve and change their environment (their host) so they are alive, even if they are simple

[@thatonedog819]

@@guifdcanalli there is a huge debate in the scientific community about if they are considered alive or not.

[@petitio_principii]

@@thatonedog819 but for LUCA and the origin of life the idea would be that they'd be something analog to the "progenotes" of Woese. Abiotically arising and/or ending up in an environment where they can reproduce or almost-reproduce without "cells," gradually evolving in a natural-selection fashion according to how they better are at actually reproducing. Then the cell itself, or first the progenote arrangement, would have been an adaptation to compartimentalize this "petri dish" environment, gathering and protecting more raw materials for reproduction. Some abiogenesis theories also postulate that maybe a gene-less proto cell could have had a role, maybe these "viruses" first captured those proto-cells and eventually learned how to catalyze their formation, progressively in a more independent manner from the abiotic origin sites.

[@petitio_principii]

@@thatonedog819 whether viruses are considered alive or not is really a bogus, dumb debate. It's equivalent to argue whether chromosomes or microchromosomes are "alive," or whether a wheel is a car, or a pair of wheels mounted on an axle is a car. The standard view is that they are not; "life" is the metabolic activity of cells, on which both chromosomes and viruses can have their roles, and end up being copied by life, by the activity around them. Nothing stops people from redefining words and making it so that viruses and chromosomes can be considered "life" even if they don't live "by themselves," only within a cell-like environment, but it's questionable what's the point of doing that, it's just semantics and making things blurrier.

[@0Tyr]

Yeah, another great video from PBS and so are the other two in this group! I love it when smart people expertly command their ability to clearly articulate complex sets of concepts.

[@stevendrysdale1067]

Great video! Love the collaboration.

[@vishalhemraj7679]

Is it possible for PBS Eons to do a video on continental drift, about how the landmasses changed during all the Era?

[@TheSuperhomosapien]

It's like a science superhero team-up!

[@mizuhonova]

Can you talk about the gene/trait for regeneration (starfish, salamanders, etc.) and why this isn't a nearly universal trait? It's almost as useful as having eyes.

[@KiraNightshade]

It might have to do with an energy tradeoff but that would be cool to see a deep dive on :)

[@albabaldomero8813]

I'm like 4ys late but we actually have the genes of regeneration, they're just "blocked" because evolution decided that it was better for us to coagulate our injuries instead of regenerate them. As useful as it is to be able to regenerate tissues and eventually organs it also entails a lot of difficulties, the risk of infection is much higher if you cut off a finger and try to regenerate it rather than just stop the bleeding for example. We just adapted that way, and other species, like salamanders and star fishes that you mentioned, adapted differently.

[@mizuhonova]

@@albabaldomero8813 That's interesting to know, Alba. Thanks for the response!

[@enderreaper1482]

@@albabaldomero8813 couldn't we do both at the same time

[@potats1770]

​@@albabaldomero8813there's been cases of full sections of cut off fingers regrowing, but usually in cases where it was cut close to the tip

[@priyankasable9107]

It was fascinating to see you all in one video.

[@lomanalchemik7749]

I know LUCA. She lives on the second floor. She lives upstairs from me. I knew i've seen her before.

[@mocha9072]

This is fantastic, thanks you guys.

[@elizabethnorth2828]

Awww I do tell everyone about Eons! I loves this channel so much :)

[@ManosTheOne]

What an amazing video!!

[@sebern2]

Love the collaboration!

[@andrewwright64]

This is such an epic collaboration!

[@meisam9592]

Best day of the days starts when 3 of your favorite channels release the video at the same time!

[@shinchonee]

Eons and it's okay to be smart are one of favourites from PBS

[@tamrisustun1704]

Thank you learnd a lot great presentation

[@NintendoPolitics]

When you recognize all these faces and think...I spend too much time on KZbin

[@ghoxon8312]

These videos are really great, and pretty accurate. But seeing the interest in the comments about different kinds of ancestral organisms, I think you should do a few episodes on how we can infer what these things were like, I.e. tree thinking and parsimony. Over at space time, they do an awesome job of making pretty advanced concepts accessible. I don’t see why it wouldn’t work here. Ps you should do an episode on resurrecting ancestral molecules. Because you know, we can do that now.

[@lexiright5609]

"I'm an astrophysicist" "I'm a gemini"

[@tinamclaughlin1991]

Right Hank! Very good!