Speaker 1: Welcome to Stuff you should know, a production of iHeartRadio.
Speaker 2: Hey, and welcome to the podcast. I'm Josh and there's Chuck.
Speaker 2: And we're doing it together, doing it, doing it. We're
Speaker 2: just doing it together, and this is stuff you should know.
Speaker 1: That's right. I have the rainy day blues, you guys,
Speaker 1: but we're doing it anyway.
Speaker 2: We're doing it together.
Speaker 1: The rain shouldn't stop an indoor podcast, right, No.
Speaker 2: But I'm with it. It's been raining too much lately
Speaker 2: and it can get to you after a while.
Speaker 1: Yeah, that's right, I'll persevere. The sun is shining in
Speaker 1: my head.
Speaker 2: Oh that's very pleasant.
Speaker 1: It's not true, but it's a nice thing to say.
Speaker 2: Okay, So that reminds me of that. I remember when
Speaker 2: Pebbles and Bambam on Flintstones had like a brief singing career.
Speaker 1: Oh yeah, wasn't.
Speaker 2: It like, let's the sunshine in? Or there is something
Speaker 2: there hit single head to do with sunshine?
Speaker 1: Well? I remember let the sunshine in? But was that
Speaker 1: the Brady bunch? Was that Pebbles and Bam Bam you
Speaker 1: let the sunshine in? Something something with the grin.
Speaker 2: I don't think it was either of them, not even
Speaker 2: the Brady Bunch though. Well, at any rate, it just
Speaker 2: reminded me of Pebbles and Bambam, so that did my
Speaker 2: heart good too.
Speaker 1: Alrighty, So can I just briefly say what we're talking
Speaker 1: about so people don't think this is about the fund Stones? Yeah,
Speaker 1: although that'd be a fun episode.
Speaker 2: Actually, I agree, I think that is a future episode.
Speaker 2: Good idea, all right.
Speaker 1: The shadow biosphere, which is to say, this notion, this
Speaker 1: theoretical notion that perhaps, if you know, we're constantly looking
Speaker 1: for life on other planets and it has been positive,
Speaker 1: well what if there if that life exists here on Earth,
Speaker 1: but it just doesn't look at all, and it's not
Speaker 1: made up of all the things that make up life
Speaker 1: as we know it here on Earth, and so we're
Speaker 1: just either looking in the wrong places or not recognizing
Speaker 1: it as something that's alive, or both. And that's the
Speaker 1: shadow biosphere, this idea. It's pretty cool.
Speaker 2: Yeah, it is pretty cool. I mean. One of the
Speaker 2: big problems that you run into when you're talking about
Speaker 2: a shadows biosphere or plotting to look for other forms
Speaker 2: of life that just don't conform to what we think
Speaker 2: of as life as we know it. The big problem
Speaker 2: is is we don't really have a working definition of
Speaker 2: life as life as we know it, like us, microbes, birds, like,
Speaker 2: there's not a real definition that covers all of them,
Speaker 2: and there is one that scientists have agreed to generally
Speaker 2: settle on. But if people who are into the shadow biosphere,
Speaker 2: which is to say, usually a combination of astrobiologists and microbiologists,
Speaker 2: it's where they're two feel overlap in a ven diagram,
Speaker 2: that's where the shadow biosphere lives, they will say like,
Speaker 2: this is holy inadequate, Like there are we need to
Speaker 2: broaden the horizons or else we're never going to detect
Speaker 2: anything that's not living.
Speaker 1: Yeah, and I'll tell you what, my friend, I hope
Speaker 1: one day during the life of the show, we do
Speaker 1: find life on other planets that significant, so you will
Speaker 1: stop doing articles about it.
Speaker 2: Well, this is so yeah, okay, fair, fair, This is
Speaker 2: a pursuit of astrobiology. But the thing that I find
Speaker 2: the most fascinating is where microbiology comes in. And they're saying, yeah,
Speaker 2: this would help us find or look for life off
Speaker 2: of Earth. Yeah, but it'll also help us find life
Speaker 2: on Earth. Like the idea that we share a planet
Speaker 2: with other trees of life that aren't related to us
Speaker 2: in any way, shape or form other than we we
Speaker 2: share the planet and they function in ways similar that
Speaker 2: life as we know it functions, but we're not related.
Speaker 1: Yeah.
Speaker 2: Yeah, I think that's neat.
Speaker 1: I think it's totally neat. And here's the other thing too,
Speaker 1: is if, and this is a pretty important note, if
Speaker 1: we do find something here on life on Earth that
Speaker 1: is like a shadow life form of some sort, we're
Speaker 1: probably talking about microbes. Just so people don't get super
Speaker 1: excited about the idea of chuds being a real thing.
Speaker 1: That's not a real thing. We're not going to We're
Speaker 1: not going to go deep down enough to find any
Speaker 1: cannibalistic humanoid underground dwellers sadly. So what we're talking about
Speaker 1: here microbes, and what we're talking about is this idea
Speaker 1: put forth by a very smart woman named Carol Cleland
Speaker 1: from the University of Colorado Go buffaloes. And I think
Speaker 1: the way she came about it was like you hear
Speaker 1: about like she came about it. Honestly, I think this
Speaker 1: is like one of those times because she was in Spain,
Speaker 1: she was observing some molecular biologists. They were looking for
Speaker 1: soil mic and microorganisms looking through these samples and she
Speaker 1: was like, hey, they went see, and she said, how
Speaker 1: do you know, like that you found something new, like
Speaker 1: a new microbe And they said, well, and I'm not
Speaker 1: going to say this in Spanish because I didn't translate
Speaker 1: at all. I just know what yes is. See, but
Speaker 1: they said, well, what we do is we look until
Speaker 1: we find something that looks like it might hold some promise.
Speaker 1: Then we you know, we've looked at it under a microscope.
Speaker 1: Then we put it in a Petri dish and just
Speaker 1: grow the heck out of it and then isolate its
Speaker 1: DNA and then look at the genome and see, like, hey,
Speaker 1: what does this look like? And then she went, oh,
Speaker 1: that's kind of cool, but I have another question. It's
Speaker 1: kind of like Tom Hanks and Big like.
Speaker 2: They get still here.
Speaker 1: She said, well, what if it's not related to life
Speaker 1: on earth? Like, how would you even know? You're like,
Speaker 1: how to recognize something as being alive? And they all
Speaker 1: shrugged and she wrote a book about it.
Speaker 2: Oh see, I imagine them all for and one of
Speaker 2: them just drops the Petrie dish without they just drop
Speaker 2: like they can't believe what they've just heard. They're stunned.
Speaker 1: Yeah, and COVID.
Speaker 2: So so, Carol Cleveland makes a really excellent point. And
Speaker 2: like you said, this kicked off the idea of shadow biospheres,
Speaker 2: and in fact she coined that term. But what she's
Speaker 2: saying is that our process of looking for life would
Speaker 2: just walk right past anything that doesn't conform to our
Speaker 2: understanding of life. But that still is living in a
Speaker 2: certain definition of things.
Speaker 1: Nailed it.
Speaker 2: Yeah, So just to kind of step back for a second,
Speaker 2: there there is a some there's a consensus among scientists
Speaker 2: that life conforms to a few rules. This is the
Speaker 2: the generally agreed upon definition of life. It's carbon based.
Speaker 2: Anything else is non living. You know, you look at
Speaker 2: a piece of courts it's from silicon, I think not living.
Speaker 2: Great example thinks it's programmed by DNA and RNA. Right,
Speaker 2: so it has transcription of its genetic code, and that
Speaker 2: is just it does not live without that. Those things
Speaker 2: are built by amino acids and proteins. Those are the
Speaker 2: basic building blocks of the organism. It's self replicating very important.
Speaker 2: And then it also evolves according to Darwinian principles, which
Speaker 2: is to say that the best properties and traits are
Speaker 2: selected for over time. So if you put all those
Speaker 2: things together, you have a pretty good idea about life.
Speaker 2: But again, this is a really narrow definition, and if
Speaker 2: you really kind of look at it, you're like, this
Speaker 2: is there's a lot of room for other things to
Speaker 2: function in a manner that's living that doesn't necessarily use
Speaker 2: DNA or RNA, that doesn't use amino acids or at
Speaker 2: the very least the amino acids that we use, and
Speaker 2: it might not even be carbon based. Like maybe we
Speaker 2: can broaden this a little bit, and that's the pursuit
Speaker 2: of shadow biosphere.
Speaker 1: Yeah, and Carol Cleland was right in the money said
Speaker 1: she wrote a book. It's really a paper, but you know,
Speaker 1: she could bind it like a book, probably sell it
Speaker 1: in a store, sure, But it was called the Possibility
Speaker 1: of Alternative Alternative Microbial Life on Earth. We're also going to,
Speaker 1: you know, talk a little bit about looking on other planets,
Speaker 1: because we've talked a lot about that and suffice to say,
Speaker 1: when we're looking for life on other planets where you know,
Speaker 1: we're always looking for like an earth like place where
Speaker 1: something like life as we know it could exist kind
Speaker 1: of in the same way. But she was like, this
Speaker 1: stuff might be right under our noses, everybody right, And
Speaker 1: here's a paper about it, and I think it was
Speaker 1: pretty smart paper. There was a should we talk about
Speaker 1: the central dogma?
Speaker 2: I guess yeah, I think we need to.
Speaker 1: Yeah. So you know, you went over what life on
Speaker 1: Earth contained, but the central dogma is a little more specific.
Speaker 1: It was first proposed by Francis Crick in the nineteen fifties.
Speaker 1: That is that DNA, the nucleic acid that we know
Speaker 1: and love, has instructions for building all the proteins that
Speaker 1: are required for something to be alive. You also have RNA,
Speaker 1: which copies those instructions to take them to the ribosomes,
Speaker 1: which also exists. Because that reads that RNA and assembles everything,
Speaker 1: all those amino acids to make each protein, and bada
Speaker 1: bing bada boom, you have life.
Speaker 2: Right, And so you take that process and you end
Speaker 2: up with what's called the origin of life, the genesis
Speaker 2: of life here on Earth.
Speaker 1: Genesis.
Speaker 2: We've talked about that. That's the scientific way of.
Speaker 1: Saying, well, okay, we go put on my lab coat.
Speaker 2: We've talked about this before multiple times. Remember we did
Speaker 2: an episode on panspermia. We've done a bunch of episodes
Speaker 2: that I think this primordial soup came up. And that's
Speaker 2: the whole idea that either in some shallow tidal pool
Speaker 2: or you know, some warm part of the ocean or
Speaker 2: some body of water, there was a bunch of those
Speaker 2: basic building blocks of life, amino acids, proteins floating around
Speaker 2: and that somehow a self replicating process got kickstarted. And
Speaker 2: the self replicating process is considered what's called a privileged function,
Speaker 2: This idea that this mechanism for creating life was present
Speaker 2: at the outset and is still around today, so we
Speaker 2: self replicate. A couple others were metabolism, that's another suggestion
Speaker 2: for the privileged function that kickstarted life. Or then compartmentalization
Speaker 2: like having something to hold all of these processes in
Speaker 2: like a bag of guts. Basically, so one of those
Speaker 2: they say is what was responsible for kickstarting this process
Speaker 2: of life, and that somehow, some a bunch of chemical
Speaker 2: reactions started a chain reaction that became self sustaining that
Speaker 2: eventually turned into increasingly complex processes, organelles, and eventually living organisms.
Speaker 2: That's how life developed. That's the idea behind the primordial
Speaker 2: soup that the central dogmas based on that's right.
Speaker 1: But in Cleveland's paper, she was like, well, hold on
Speaker 1: a second, that's great, what a story. We love it,
Speaker 1: we all believe it. But what if this happened like
Speaker 1: more than one time. What if it happened multiple times
Speaker 1: right here on Earth there were just different conditions in
Speaker 1: different places, different chemicals came together. And what if that
Speaker 1: happened and these are the shadow microbes? And what if
Speaker 1: this stuff is still there? And the reason that we
Speaker 1: haven't found it is because we're looking for again for
Speaker 1: life that we understand as being alive and the ramifications
Speaker 1: that would have not only to find stuff like that
Speaker 1: here on Earth, but you know this idea that when
Speaker 1: we go out and look in outer space for life
Speaker 1: on other planets again we're looking for earthlike, you know,
Speaker 1: atmospheres and Earth like conditions. She was like, well, what
Speaker 1: if we're looking on the entirely wrong planets. There could
Speaker 1: be stuff that's alive because we're just not looking in
Speaker 1: the right places because we have such a narrow definition.
Speaker 2: Yeah, and we definitely have found increasingly extremophile organisms, like
Speaker 2: for a long time we thought that organisms couldn't survive
Speaker 2: past one hundred and twenty something degrees farenheight. Then we
Speaker 2: found some extremophiles that can survive around hydro thermal events
Speaker 2: that are as hot as two hundred and twelve degrees farentheight. Like, okay,
Speaker 2: that's pretty awesome, but it's still life as we know it,
Speaker 2: you know, like they're crazy in their adaptation, but they
Speaker 2: still function according to the properties of life as we
Speaker 2: know it. What Carol Cleland and others are saying is like, Okay,
Speaker 2: we'll keep looking in even more extreme and vironments and
Speaker 2: eventually you may find something that has had to adapt
Speaker 2: to such an extreme environment. It uses different processes or
Speaker 2: different raw materials that life as we know it could
Speaker 2: not possibly use. And there you have your first shadow
Speaker 2: bio organism.
Speaker 1: I think we should pick a great rest here. Rest.
Speaker 2: We'll be back everybody after this rest.
Speaker 1: And lo, the podcasters rested low and then on day
Speaker 1: two they got on with the show. We should mention,
Speaker 1: by the way, we did a pretty good episode on extremophiles, yeah,
Speaker 1: a while back, So just if you haven't heard it,
Speaker 1: you should just look up on the search engine of
Speaker 1: your choice extremophile so if you should know, pretty neat.
Speaker 1: But back to the shadow biosphere. You know, we mentioned
Speaker 1: the fact that you know, Carol Cleveland's beating that drum, saying,
Speaker 1: what if it's not something that we recognize because we
Speaker 1: just don't recognize it as life as we know it.
Speaker 1: And then she started digging in and she was like,
Speaker 1: here's the thing. DNA and RNA aren't the only building
Speaker 1: blocks of life. In theory. They are made of base
Speaker 1: pairs of nucleic acids. For DNA, it's a D nine
Speaker 1: cyanine quinine, and thymine. For RNA it's thymine that is
Speaker 1: swapped out for ucell. But there are other three are
Speaker 1: the same, but there are more nucleic I believe there's
Speaker 1: six more nucleic acids that exists exist in nature. So
Speaker 1: you know, why are we not even considering the fact
Speaker 1: that those could be a part of life in a
Speaker 1: way that we don't fully understand.
Speaker 2: Right, And first, ursill sounds like over the counter urinary
Speaker 2: tract infection treatment totally does. Secondly, I could not, for
Speaker 2: the life of me and I really looked find what
Speaker 2: the other six nucleic acids are. I can't find it, Chuck.
Speaker 2: But in that search I did come across something called
Speaker 2: the hatch emoji DNA, which is those four at, which
Speaker 2: is always together in GC, which are always together to
Speaker 2: form those base pair nucleotides that eventually build up into DNA.
Speaker 2: And they added p z B and.
Speaker 1: S and let's see them right.
Speaker 2: Well, that's four, so there's still two many. But the
Speaker 2: really interesting thing that they found is that if you take,
Speaker 2: if you rearrange say the original four bay pairs, or
Speaker 2: you add these other brand new four base pairs and
Speaker 2: run them through a ribosome, the ribosome, if you arrange
Speaker 2: it correctly, and they're made of nucleic acids, the ribosome
Speaker 2: will be like, okay, I'm transcribing this, So it's entirely possible.
Speaker 2: They proved that it's possible that life could have evolved
Speaker 2: separately from us by using different amino acids but similar mechanisms.
Speaker 2: So maybe we are or could be, in this sense
Speaker 2: distantly related to them, like maybe in the primordial soup,
Speaker 2: but it branched off so early that for all intents
Speaker 2: and purposes, it's non living life as far as our
Speaker 2: definition of life goes.
Speaker 1: Yeah, well, nice job finding four of those six letters.
Speaker 1: At least, let's just call the other two FU.
Speaker 2: Science.
Speaker 1: Yeah, so that's how DNA and RNA could be you know,
Speaker 1: different as we know it. The same thing is true
Speaker 1: for amino acids. All the proteins are built from the
Speaker 1: same combination of twenty amino acids, because when Earth formed,
Speaker 1: those were the twenty amino acids that, in a Darwinian sense,
Speaker 1: were most successful making proteins that survived when life emerged.
Speaker 1: There are five hundred we're not gonna name them, five
Speaker 1: hundred other amino acids, or more than five hundred amino
Speaker 1: acids on Earth. So yeah, totally. So it's just the
Speaker 1: fact that Earth started when it did that those particular
Speaker 1: twenty amino acids were the ones that were good at
Speaker 1: doing what needed to be done to make things that
Speaker 1: survived here. But it could have been, you know, at
Speaker 1: a different time. It could have been any other combination
Speaker 1: of amino acids, and they're.
Speaker 2: Still out there exactly. So a lot of scientists are like, well,
Speaker 2: that just goes to show you that life as we
Speaker 2: know it is the only kind of life. If we're
Speaker 2: using the same twenty amino acids and there's all these
Speaker 2: others out there, these are the ones that got selected
Speaker 2: for These are the ones that worked in the primordial
Speaker 2: soup and caroclelans forward again with her index finger raised
Speaker 2: and says, Okay, I can see where you're coming from.
Speaker 2: But again, as I said before, if life emerged in
Speaker 2: other places, in other situations, under other conditions, in the
Speaker 2: primordial soup, it's entirely possible that completely different combinations of
Speaker 2: the other kinds of amino acids were the most usable,
Speaker 2: and we're selected for that. And again, this is how
Speaker 2: the shadow of biosphere could have started. And another petri
Speaker 2: dish got dropped. And these guys are starting to second
Speaker 2: guess undermining Carol Cleland, or even attempting to because she
Speaker 2: just keeps facing them over again.
Speaker 1: Yeah, and they're like, well, how would that have happened
Speaker 1: or how could that happen? She said, I don't know.
Speaker 1: How about a meteor sucker because meteorites have fallen to
Speaker 1: the Earth and asteroids that basically plant stuff on Earth
Speaker 1: that come from another place. There have been meteorites that
Speaker 1: have fallen that are carrying up to eighty other amino acids.
Speaker 1: And her whole theory is it like, what if this
Speaker 1: has happened, and maybe it's happened repeatedly, and again we
Speaker 1: just don't know about it because we're not looking correctly, right.
Speaker 2: So, yeah, the panspermia episode that was the basis of it,
Speaker 2: that Earth got seated with the necessary ingredients for life
Speaker 2: from space. Right, that's right. So there's another peculiar aspect
Speaker 2: of life as we know it that doesn't really make
Speaker 2: sense to us, and I don't fully get how it
Speaker 2: would tie into the shadow biosphere. So if you do,
Speaker 2: let me know. But the best I can understand is
Speaker 2: that because we don't know it, and because it's like
Speaker 2: it just seems like a random, arbitrary development in life
Speaker 2: as we know it, that it suggests things could go
Speaker 2: the other way and maybe they have elsewhere on Earth.
Speaker 2: Is that how you read it too?
Speaker 1: Yeah? I think so. Okay, just like an example of like,
Speaker 1: see this can happen.
Speaker 2: Right, Okay, good, That's what I'm taking as too. And
Speaker 2: we're talking about chirality, and chiralness is handedness and Greek
Speaker 2: you're either right handed or you're left handed, or you
Speaker 2: could be ambidextrous. But that's neither hum nor there. When
Speaker 2: we're talking about cellular biology or molecular science, which is
Speaker 2: what this pertains to, and if you make a bunch
Speaker 2: of sugars or a bunch of amino acids in the lab.
Speaker 2: Some are going to be left handed and some are
Speaker 2: going to be right handed. But as far as life
Speaker 2: on Earth is concerned, only left handed amino acids and
Speaker 2: only right handed sugars can be useful as the building
Speaker 2: blocks of life. So there's right handed amino acids and
Speaker 2: left handed sugars, but they are completely useless to us
Speaker 2: because all life on Earth only uses left handed amino
Speaker 2: acids and only uses right handed sugars. And we just
Speaker 2: don't know why.
Speaker 1: Yeah, and if this sounds like, all right, guys, what
Speaker 1: are you talking about here with these hands, it's not hands,
Speaker 1: it's the direction that their atoms are oriented. Yeah, they
Speaker 1: talk about it in terms of handedness. I think just
Speaker 1: as a well, I hate to say it is a shorthand.
Speaker 1: So dumb humans like us can understand what they're talking
Speaker 1: about at least halfway right.
Speaker 2: And so, because there's left handed and right handed amino acids,
Speaker 2: they are mirror images of one another. They're constructed the
Speaker 2: exact same way. They're constructed with the exact same components
Speaker 2: to make up these molecules, but they are mirror images.
Speaker 2: So if you overlay them, they're not twins mirror images.
Speaker 2: So in exactly the same way. If you hold your
Speaker 2: hands out in front of you, palms down so the
Speaker 2: tops up, and you just kind of hold one over
Speaker 2: the other, they're not twins. They're mirror images of one another.
Speaker 2: And that's exactly true with amino acids and sugars. They
Speaker 2: each have a mirror image. And again, only one kind
Speaker 2: is useful to life. The other ones just get spit out.
Speaker 2: So what if, again, under different conditions, at some point
Speaker 2: in the past, there were organisms that learned to use
Speaker 2: the other kind left handed sugars and right handed amino acids,
Speaker 2: that would certainly qualify as a shadow biosphere bioorganism.
Speaker 1: Yeah, and we have synthesized these in labs. But what's
Speaker 1: the deal. What I don't understand. If they were able
Speaker 1: to synthesize it, that means that it did already exist,
Speaker 1: but it just isn't anything that was alive.
Speaker 2: Yeah, I don't know exactly what they did. They built
Speaker 2: a cell that uses right handed sumino acids. Yeah, yeah,
Speaker 2: and they I don't know if it was living or not.
Speaker 2: I don't think it was living or else they would
Speaker 2: be like we created artificial life here. I don't think
Speaker 2: anyone's ever done that. I think they just created the
Speaker 2: structure of it. Like if there if there was something
Speaker 2: like a cell that use that kind of stuff, this
Speaker 2: is what it would be structured as. The whole reason
Speaker 2: they built it was to try to attract things like
Speaker 2: chiro viruses that function using the opposite stuff that we
Speaker 2: use for life. It was a honeytrap, is the way
Speaker 2: that they put it.
Speaker 1: Like they take it out to a club and set
Speaker 1: it on a bar table and they're like, hello, everybody,
Speaker 1: exactly right.
Speaker 2: So nothing came along and took the bait, But that
Speaker 2: doesn't mean it's not there. The better argument against things
Speaker 2: like that living, if you asked me that I ran across,
Speaker 2: is that if you did have something like that that
Speaker 2: could consume other things, it would have no natural predators.
Speaker 2: It would it would not be able to be infected
Speaker 2: by any of the known viruses we have. It would
Speaker 2: be unstoppable, and it would replicate in such an unchecked
Speaker 2: manner that it would apocalyptically destroy the food web based
Speaker 2: on whatever, you know, one microbe that it feasted on.
Speaker 2: And because that's not happen, and there's a pretty good
Speaker 2: chance that there's no such thing as that.
Speaker 1: Yeah, I guess now we can talk a little bit
Speaker 1: about the last universal common ancestor or the LUCA, which
Speaker 1: is the idea that all life on Earth can be
Speaker 1: traced back to this very first functioning cell that started
Speaker 1: the whole party. If we believe in something like the
Speaker 1: shadow biosphere, there can still be a last universal common ancestor,
Speaker 1: I think in terms of what created our life. But
Speaker 1: we have to consider the fact that there were multiple
Speaker 1: genesis that happened at a certain point and you know,
Speaker 1: maybe they just didn't evolve because you know, part of
Speaker 1: that opening four things that we talked about was that
Speaker 1: things evolved in a sort of the Darwinian sense that
Speaker 1: we recognize. But the idea of the shadows biospheres, maybe
Speaker 1: these things did occur at various sort of calm periods
Speaker 1: on Earth where there weren't you know, ice ages, or
Speaker 1: it wasn't being bombarded by asteroids, and that there's still
Speaker 1: they just never evolved. They're just sort of trapped.
Speaker 2: Yeah, that's one example. There's another explanation that they might
Speaker 2: be in places we haven't explored yet, so like there
Speaker 2: could be you know, life on the surface of Earth
Speaker 2: and then we find microbes all the way down to
Speaker 2: some you know level and it gets too hot for them,
Speaker 2: and then it's a dead zone. Well maybe beyond the
Speaker 2: dead zone there's these you know, shadow biosphere organisms. And
Speaker 2: then another argument I saw against the idea. So a
Speaker 2: lot of scientists are like, sure, it's entirely possible there
Speaker 2: were different origins of life, but the other one sputtered out,
Speaker 2: only ours continued on a lot of that's not a
Speaker 2: very controversial idea. What's controversial is that it didn't sputter out,
Speaker 2: that they just evolved and we share Earth with them, right,
Speaker 2: But a lot of the arguments against that state that, Okay,
Speaker 2: well maybe it did make it beyond the sputtering stage,
Speaker 2: and it was you know, we shared the primordial soup
Speaker 2: with it, but it got absorbed into us and now
Speaker 2: it's a part of us, but you know, not really anymore.
Speaker 2: And that misses the point because what they're talking about
Speaker 2: is lateral gene transfer, where like say one cell just
Speaker 2: takes over another cell and they share DNA from that
Speaker 2: point on. That's totally missing the point. Like that would
Speaker 2: not be a shadow organism, it'd be an early additional
Speaker 2: ancestor to us. This is stuff that we couldn't possibly have,
Speaker 2: you know, mixed with to become us or else it
Speaker 2: wouldn't be a shadow bio organism. It would just be
Speaker 2: another component that created life as we know.
Speaker 1: Would That's right, And lateral gene transfer was totally an
Speaker 1: a cappella skiking group from the seventies, a gospel group, oh,
Speaker 1: led by a guy named Gene Nice.
Speaker 2: Nice.
Speaker 1: Yeah, I've got the record. It's not even a joke.
Speaker 2: Are you kidding? You're not kidding? Ah, wow, you did
Speaker 2: get me. That was finally, Well, we're pretty wacky, so.
Speaker 1: Oh goodness. It is a meal, best serve cold.
Speaker 2: Do you do you want to take a break and
Speaker 2: savor that for a little while.
Speaker 1: Uh yeah, sure, let's go ahead and take a break.
Speaker 1: I'm going to take another nap and dream about getting
Speaker 1: Josh and then we'll be right.
Speaker 2: Back, all right, Chuck. So we said that, or I
Speaker 2: should say, you said at the outset that nobody's looking
Speaker 2: for you know, some silicon were wolf or something so great.
Speaker 2: So instead there were we're looking for my crubs. And
Speaker 2: the reason that everybody agrees if there is a shadow
Speaker 2: by its microbial life is a couple of reasons. One
Speaker 2: we could look at a microbe and look right past it.
Speaker 2: They don't have faces, they don't have tails, they don't
Speaker 2: have hair, they don't really have any features that would
Speaker 2: really stand out just visually. We have to really examine
Speaker 2: them to find the differences that we would be looking for.
Speaker 2: And then on top of that, we've only cultured and
Speaker 2: described less than one percent of all of the estimated
Speaker 2: species of microbes on Earth, right so we have very
Speaker 2: little understanding in the big picture of the microbial life
Speaker 2: we share Earth with. So it's entirely possible we just
Speaker 2: haven't stumbled upon one yet. But that doesn't mean it's
Speaker 2: not there in that other ninety nine percent of the
Speaker 2: kinds of microbes on Earth with us right.
Speaker 1: Now, Yeah, for sure. And you know we've kind of
Speaker 1: walked around this very plain statement. But the plain statement
Speaker 1: is look where we think or look where we so
Speaker 1: far think that nothing here can live, because that might
Speaker 1: be a great place to start, you know, if we're like,
Speaker 1: nothing can live in the dead sea micro organisms, because
Speaker 1: it's just it's so full of saline that we just
Speaker 1: know nothing could live, Like, well, maybe start there, or
Speaker 1: you mentioned earlier the fact that things we didn't think
Speaker 1: anything could sustain life greater than like one hundred and
Speaker 1: twenty two degrees fahrenheit. But then we discovered colonies of
Speaker 1: bacteria that could. We're like, well, that's evidence right there
Speaker 1: that maybe we should look in like really really hot places,
Speaker 1: really really cold places, really acidic places, really base places.
Speaker 1: Anything on the list that says human life can't exist there,
Speaker 1: maybe start looking there.
Speaker 2: What's crazy is when we have looked there, we keep
Speaker 2: finding stuff that can exist, like life that yeah, doing
Speaker 2: just fine there that just should not be there. The
Speaker 2: best example I found are types of I think slime
Speaker 2: mold maybe or algae that it lives in abandoned uranium
Speaker 2: minds so this place is so crazy radioactive, No life
Speaker 2: should be able to survive there, and yet they think
Speaker 2: these things are actually taking that radiation and using it
Speaker 2: as chemical energy. And then there's also a kind of
Speaker 2: single cellular life that they found growing in one of
Speaker 2: the abandoned chernobyl reactors. Again should not be aware because
Speaker 2: of the radioactivity. But these things still conform to the
Speaker 2: basic principles of life as we know it. The point is, though,
Speaker 2: is you just keep thinking in more and more extremes,
Speaker 2: and you know, maybe we'll find it like the upper
Speaker 2: atmosphere is the one that suggested because no life's supposed
Speaker 2: to be able to live up there because of the
Speaker 2: cosmic rays and the temperature and all that stuff. It's
Speaker 2: just not a pleasant place to live from what I understand.
Speaker 2: And then other people are like, Okay, if we keep
Speaker 2: looking and in these more extreme environments and we're just
Speaker 2: finding life as we know it, maybe we should look
Speaker 2: around and see if we find anything weird in places
Speaker 2: like right under our very noses. And one of the
Speaker 2: big ones that has been touted is desert varnish. And
Speaker 2: this one, from what I can tell, is still the
Speaker 2: jury's out whether it's a shadow bio organism.
Speaker 1: Yeah or not or not. You're hanging out there like
Speaker 1: a chad. So yeah, if you've ever been out to
Speaker 1: the desert in the United States, if you've ever driven
Speaker 1: around like Utah or Arizona, maybe even Colorado, maybe New Mexico,
Speaker 1: you might have been driving along and seeing like a
Speaker 1: very sheer sort of cliff face, and within that cliff
Speaker 1: face you might be like, oh, that's just weird, sort
Speaker 1: of shiny, dark area of it. There are always really
Speaker 1: arid environments. Indigenous peoples used to create petroglyphs, so instead
Speaker 1: of like you know, writing on something, they would scrape
Speaker 1: away that varnish to make their art for the original
Speaker 1: lighter colored earth underneath it. But I mean, I've seen
Speaker 1: these things in person. I've driven by it, and I
Speaker 1: didn't know what it was. I just figured it was
Speaker 1: dark rock or something. But it's called desert varnish, and
Speaker 1: scientists have been fascinated for a long long time. One
Speaker 1: reason is because it grows about the pace of a
Speaker 1: width of the human hair every millennium, and because that
Speaker 1: happens so slowly, they were like, well, this is just
Speaker 1: a geological process that's going on, maybe the sun hitting it,
Speaker 1: some sort of chemical reaction takes place. But they found
Speaker 1: that that's it's actually a living thing, right.
Speaker 2: They don't know there's no geochemical process that accounts for it.
Speaker 2: There's no biological process that accounts for it. They just
Speaker 2: don't know. It's largely manganese in nature. But the problem
Speaker 2: is it's not drawing manganese out of the rock, like
Speaker 2: a lot of these rocks don't have any manganese or
Speaker 2: have such trace amounts that it certainly wouldn't account for
Speaker 2: this desert varnished. So they just don't know how this
Speaker 2: stuff is growing or what it is. But it's probably
Speaker 2: the greatest contender right now for a shadow organism from
Speaker 2: what I can tell. Like they're like, well, then it
Speaker 2: must be a geochemical process. We just don't understand. And
Speaker 2: it's like, maybe what you're calling geochemical is actually life
Speaker 2: in a different manner.
Speaker 1: Yeah, I guess there's just said the theory that it's
Speaker 1: alive that is biochemical.
Speaker 2: Yeah. There was also one that was like we founded everybody,
Speaker 2: we found the shadow organism and it went downhill from
Speaker 2: there back in twenty ten.
Speaker 1: Yeah, that was gfag dash one that is a bacterium
Speaker 1: that was found in Mono Lake, California, And they were like, well,
Speaker 1: this bacterium is really weird because it doesn't it's not
Speaker 1: sort of playing by the rules that we understand. Because
Speaker 1: if you're going to be a living thing to make
Speaker 1: DNA and RNA, you need phosphorus, and it doesn't look
Speaker 1: like this thing is using phosphorus. It looks like it's
Speaker 1: using arsenic, which would be a huge, huge mind And
Speaker 1: so they thought GFA j dash one, you're you're the dude,
Speaker 1: And everyone was really hot on this idea, and then
Speaker 1: they did follow up experiments and very sadly found out
Speaker 1: that it used very very very small amounts of phosphorus
Speaker 1: and it just wasn't instantly evident. So they're like, all right,
Speaker 1: just another extremophile. That's that we understand.
Speaker 2: Yeah, now we know.
Speaker 1: So cool.
Speaker 2: That's another benefit of it, Like we're finding stuff because
Speaker 2: we're out looking for shadow life. We're finding other life
Speaker 2: still too, So that's I mean, it's not like they're like, oh,
Speaker 2: another extra file. It's never been seen in the history
Speaker 2: of humanity.
Speaker 1: Just juke it.
Speaker 2: That's an interesting way that you pronounced that. I've been
Speaker 2: in my head pronouncing it gufage, you know. So okay,
Speaker 2: let's move on. Let's move on to life with the
Speaker 2: y chuck, because I think that that's a good next
Speaker 2: place to start.
Speaker 1: Yeah, there's a guy. Well here's the idea, is that, like, hey,
Speaker 1: maybe there is just we should just accept the idea
Speaker 1: that l i f E isn't all we think it is,
Speaker 1: and maybe it's broader than that and maybe or maybe
Speaker 1: we just need another definition l y f E. And
Speaker 1: I think that was put forward by an astrobiologist named
Speaker 1: Stuart Barleot not Bartlett, just Barlatch, And he said, well,
Speaker 1: maybe that is the l y f E definition is
Speaker 1: just any system and this is a quote any system
Speaker 1: that fulfills all four processes of the living state, namely dissipation,
Speaker 1: auto catalysis, catalysis either one, catalysis, homeostasis, and learning.
Speaker 2: Yeah, so just to get into it real quick, dissipation
Speaker 2: means that it dissipates energy or something like waste brought
Speaker 2: byproducts like heat. That's a big one. Or else it'll
Speaker 2: overheat and die, or it will never poop out its
Speaker 2: food and will die from that. That's it's just a
Speaker 2: really easily overlooked component of something organism that can keep going. Also,
Speaker 2: it needs to be able to make more copies of itself.
Speaker 2: That's that auto calysis, catalysis, auto catalysis, Sure, that's that's
Speaker 2: important because what it's doing is it's creating a process
Speaker 2: that creates another version of itself and also a product
Speaker 2: that triggers that process over again, so it can just
Speaker 2: keep going. It also has to be able to maintain homeostasis,
Speaker 2: so it can't just go totally haywire anytime you know,
Speaker 2: somebody nearby coughs. And then lastly, it's got to be
Speaker 2: able to record information about the environment like this is
Speaker 2: how you keep from going haywire when somebody coughs, and
Speaker 2: it can be encoded in some way, shape or form,
Speaker 2: so it can be passed on to the replicants of itself. Yeah,
Speaker 2: that's life with a why. And I think that's exactly
Speaker 2: the kind of broadened definition that we need. And the
Speaker 2: other thing about life with a why, that includes life
Speaker 2: with an eye, like life as we know it, and
Speaker 2: just saying life with an eye is so much less
Speaker 2: clunky than life as we know it, and it falls
Speaker 2: under a larger umbrella. So it's a broader definition that
Speaker 2: includes life as we know it, but also potentially includes
Speaker 2: members of the shadow biosphere as well.
Speaker 1: Yeah, and what this potentially means is if there is
Speaker 1: life with a why here or elsewhere, that means that
Speaker 1: kind of anything is possible. It doesn't mean that, hey,
Speaker 1: there's intelligent life out there, but it doesn't mean there's not.
Speaker 1: I mean it would certainly kind of interest toward that idea.
Speaker 1: In a very real way, we found that there is
Speaker 1: a different kind of life we just never understood before
Speaker 1: here or elsewhere. There's an astrophysicist named Paul Davies really
Speaker 1: smart guy obviously who has done a lot of scholarship
Speaker 1: work about intelligent life elsewhere, and he talks about timing
Speaker 1: a lot, like, you know, Earth happened the way it did,
Speaker 1: and it's kind of like what we touched on earlier.
Speaker 1: Earth happened the way it did because of the timing
Speaker 1: of it all. We've been around for about four and
Speaker 1: a half billion years, and we won't be around in
Speaker 1: about a billion years, Like the Earth will be scorched
Speaker 1: basically by the Sun, and it was just sort of
Speaker 1: cosmic luck that everything evolves when it did as it did,
Speaker 1: because there's a kind of a short window in the
Speaker 1: grand scheme of things between when something starts happening and
Speaker 1: being able to get to the point where you have
Speaker 1: like intelligent life like human beings and the planet being
Speaker 1: scorched or being blasted away by a large Yeah.
Speaker 2: So Paul Davies's argument kind of suggests that life is
Speaker 2: probably pretty rare, if not singular, like the only we
Speaker 2: do know that life emerged once in the entire universe
Speaker 2: that led to us in all life as we know it,
Speaker 2: but that's it. We don't know that life emerged anywhere
Speaker 2: else any other time, including on Earth. And that's one
Speaker 2: of the things that would make detecting a shadow biosphere
Speaker 2: so amazing, is it would it would essentially immediately say
Speaker 2: the universe is teeming with life. If life developed two
Speaker 2: different ways on the same planet. That strongly suggests that
Speaker 2: not only is there life elsewhere in the universe, but
Speaker 2: that biology is as immutable a cosmic or universal law
Speaker 2: as physics or chemistry. Right that if you have even
Speaker 2: just a few components put together that that gives rise
Speaker 2: to life, biology is going to take over and life will.
Speaker 2: That's ultimately the most exciting thing that gets scientists jazzed
Speaker 2: about looking for the shadow biospheres. What the implications that
Speaker 2: we'll have about us sharing life elsewhere in the universe.
Speaker 1: Yeah, totally pretty cool stuff.
Speaker 2: Huh Yeah, I like it, Chuck, I'm glad that we
Speaker 2: did this. Thanks for doing it with me.
Speaker 1: It was fun. We got through it.
Speaker 2: Yeah, we did well. Since we got through it, everybody,
Speaker 2: that means it's time for listener. Mayo.
Speaker 1: I'm gonna just read this one from Joel because it's
Speaker 1: kind of just a fun little little ditty. Hey, guys,
Speaker 1: I guess it's not a diddy. It's a story. First off.
Speaker 1: I want to say thanks for all the work you
Speaker 1: do to create an enjoyable and informative listening experience. I've
Speaker 1: been a casual listener since twenty eighteen, and your show
Speaker 1: has positively redirected the course of my day or staved
Speaker 1: off boredom through long winter nights. Because I live on
Speaker 1: Salt Spring Island, BC, off the coast of Vancouver Island
Speaker 1: and work at a golf course there. Today I was
Speaker 1: mowing the fairways on a wet and dreary morning. I
Speaker 1: put on the Manson Murders podcast and relax into my work.
Speaker 1: Part Way through, Dennis Wilson came into the story and
Speaker 1: Chuck mentioned his solo album. I think it's called Pacific
Speaker 1: Ocean Blue.
Speaker 2: Maybe I don't know.
Speaker 1: I think so great record. Feeling a little low, I
Speaker 1: decided to pause the podcast and listen to the full album.
Speaker 1: I listened to all the songs as I continued my
Speaker 1: mo lines. Truly a wonderfully enjoyable album. Thank you for
Speaker 1: that excursion into the music. Once the album finished, I
Speaker 1: listened to the mower for a few minutes and then
Speaker 1: resumed the podcast. And the first words I hear are
Speaker 1: Chuck saying Eventually they leave Dennis Wilson's house and I
Speaker 1: chuckled as I genuinely felt I had just been in
Speaker 1: his house myself.
Speaker 2: Nate.
Speaker 1: Anyway, short little story for me. Thank you for the
Speaker 1: years of entertainment. Keep up the great work that is
Speaker 1: from Joel. And Joel sent a picture of that fairway
Speaker 1: mode while listening to Pacific Ocean Blue and Joel as
Speaker 1: a beautiful golf course and I would love to play
Speaker 1: it one day.
Speaker 2: Oh, very nice. Yeah you're a golfer. I forget that
Speaker 2: sometimes I am.
Speaker 1: I'm not very good, but I enjoy putting the phone
Speaker 1: away for five hours and walking around with my buddies
Speaker 1: in the sunshine.
Speaker 2: Very nice. Well, thanks a lot, Joel, much appreciated. We
Speaker 2: love stories like that, And if you want to be
Speaker 2: like Joel, send us an email. Send it off to
Speaker 2: stuff podcast at iHeartRadio dot com.
Speaker 1: Stuff you Should Know is a production of iHeartRadio. For
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