Speaker 1: Hey, ever you wanted, it's me Josh, And for this
Speaker 1: week's s Y s K Selecta, I've chosen How Fossils Work,
Speaker 1: which actually is one of the most scientifically interesting, amazing,
Speaker 1: mind bending episodes that we've ever done. And I just
Speaker 1: listened to it and it still holds up. So I
Speaker 1: hope that you enjoy it. And as they say on
Speaker 1: with the show, welcome to Stuff you should Know from
Speaker 1: house Stuff Works dot com. Hey, and welcome to the podcast.
Speaker 1: I'm Josh Clark with me as always as the intrepid
Speaker 1: paleontologist Charles W. Chuck Bryant. It's terrible' no I like it. Okay,
Speaker 1: I wish I was a paleontologist. Let your new nickname
Speaker 1: or intrepid at least, let's just go with paleontologists. That'd
Speaker 1: be great. Okay, we're talking fossils today, Dude, this isn't
Speaker 1: really interesting stuff. It really is. And um, you can
Speaker 1: tell that Tracy Wilson are esteemed head of the writing editor.
Speaker 1: I think she's site director director, right. Um you can
Speaker 1: tell that she was very, very excited. She took her
Speaker 1: time and really doled this one out. I think um
Speaker 1: savor is the right word. You can feel it her
Speaker 1: smiling through the keyboard. Yeah, she's very happy to write
Speaker 1: how fossils work. And um, we're happy to do it
Speaker 1: because it's one of those very comprehensive articles on the
Speaker 1: site that you just has everything you need. Sedimentary rock,
Speaker 1: flat bones versus round bones, leaf impressions, has it all.
Speaker 1: Unless you're an intrepid paleontologist. Then we'll get an email
Speaker 1: saying it actually wasn't very comprehensive. You guys royally screwed
Speaker 1: this up. We just wait until we get into punctuated
Speaker 1: versus gradual evolution. Chuck. Um, you've heard of Lucy right,
Speaker 1: the Australia Kiss. Yeah, okay, Well, um, she was I
Speaker 1: think three point two million years old. That's one old lady.
Speaker 1: It really is the earliest hominid we've found as far
Speaker 1: as I know. Um. But there is a part of
Speaker 1: her foot missing. It's always been missing that we've never
Speaker 1: found before. So this thing, this bone, was so essential
Speaker 1: and we couldn't tell how she walked until recently. Why
Speaker 1: because the missing bone, we couldn't tell how she walked exactly.
Speaker 1: We we we can tell so much from bones that
Speaker 1: when we don't have the right bones we can't tell anything.
Speaker 1: So she may have been in a knuckle dragger, she
Speaker 1: may have hopped. We didn't know. Well. Recently, UM, some
Speaker 1: people from the University of Missouri or Missouri, depending on
Speaker 1: whether or not you live in the state. UM found
Speaker 1: the Uh, the group of foot bones needed to show
Speaker 1: what kind of walker Lucy was. And she walked up right?
Speaker 1: How was her gate? Upright? Upright? Just like a human.
Speaker 1: She had a hitch and her get along, she had
Speaker 1: a pepper and her step. Possibly she knew she'd be
Speaker 1: famous one day. She was loved with duc But but
Speaker 1: consider this, right, Okay, three point two million year old
Speaker 1: footbones were found, and we could tell from them how
Speaker 1: she walked. This is the state of the field that
Speaker 1: you remember paleontology. Pretty cool. This is how advanced it is.
Speaker 1: And yet it's really just kind of using common sense
Speaker 1: to figure out what old bones mean. Common sense and science.
Speaker 1: Fossils go, let's talk about it, Chuck, what are some
Speaker 1: of the different kinds of fossils. Uh, well, one of
Speaker 1: my favorite kinds of trace fossil. Yeah, that's actually one
Speaker 1: of my favorites too. It's like, um, that Jesus footprint thing.
Speaker 1: Footprints in the sand. Yeah, sort of is josh um.
Speaker 1: That is when it's actually not part of the organism
Speaker 1: at all, but it's um like tooth marks in a
Speaker 1: chunk of wood from a saber tooth tiger. Or footprints
Speaker 1: or footprints or track ways as Tracy calls them. Yes,
Speaker 1: footprints tracks. It's just unnecessary, but it has a pleasant tone,
Speaker 1: you know science. Yeah, like they're not footprints, they're track ways.
Speaker 1: I'm bored in Ethiopia, let's call him track ways. So
Speaker 1: trace fossils is one. Of course, there's bone fossils, right,
Speaker 1: the most famous fossils. Yeah, those are great too. They
Speaker 1: got nothing on trace fossils. So actually, bone fossils, that's
Speaker 1: that's what you really want. If you're going to reconstruct
Speaker 1: the dinosaur for your museum. You can't deal it with footprints, No,
Speaker 1: you can't. You need the bones, you do. And the
Speaker 1: bones are of course the most famous ones in the dinosaur.
Speaker 1: Bones are the most famous of all the bone types. Right.
Speaker 1: So there's something that I think um is often missed
Speaker 1: by lay people such as myself, um and in that
Speaker 1: when you find a bone, right, so you find like
Speaker 1: a big old dinosaur bone, it's really geologically speaking, it's
Speaker 1: not a bone any longer. It's not like you find
Speaker 1: a bone buried in your yard that was an animal
Speaker 1: from like, you know, thirty five years ago, But that's
Speaker 1: not a fossil. We'll not still bone. A fossil is
Speaker 1: a bone or a piece of um once living organic
Speaker 1: material that's undergone a transition from uh, an organic state
Speaker 1: to an inorganic state. That's what a fossil is. It's
Speaker 1: gone through the process of fossilization. And most of these fossils,
Speaker 1: the vast majority of fossils, are found in sedimentary rock.
Speaker 1: Before we're go any further, we should probably do a
Speaker 1: little brief primerun sedimentary rock, right, which is awesome. Yeah,
Speaker 1: it's pretty easy to Uh. We've talked about the Earth's
Speaker 1: core um and layers. When I think we talked about
Speaker 1: earthquakes and maybe some other stuff. We all know that
Speaker 1: there's the intercore, outer core. We got the crust. Crust
Speaker 1: is the thinnest layer, and that's where the fossils are.
Speaker 1: That's where the goods are. And uh, most of the
Speaker 1: rocks in the crust are sedimentary rocks that you've been
Speaker 1: talking about off and on for the past eight minutes, right,
Speaker 1: and that's like silty sandy stuff that hardened over the years, right,
Speaker 1: I mean, but the the Earth. Remember we talked about, oh,
Speaker 1: what was it, clouds. I can't remember what podcast it was,
Speaker 1: but we talked about how much sand is transferred from
Speaker 1: Africa to South America annually. Yeah, it wouldn't clouds, but yeah,
Speaker 1: if you you remember the one I'm talking about. Okay, So,
Speaker 1: the Earth's geo biogeochemical processes equal a lot of movement
Speaker 1: of particulate matter. Right. The Earth is dynamic, baby, it is.
Speaker 1: It's also very fluid. To write, a lot of that
Speaker 1: matter is at at one point as suspended particles in
Speaker 1: water that's moving around, right. Yeah. So um, as this
Speaker 1: as the water leaves and the sediment is deposited, it
Speaker 1: builds up and up and up. Over time, it hardens
Speaker 1: into rock and eventually we have sedimentary rock, yeah, which
Speaker 1: is below our feet. We don't normally see it unless say,
Speaker 1: the Colorado River um winds over it for you know,
Speaker 1: millions and millions and millions of years, revealing the sedimentary
Speaker 1: rock that's in the Earth's crust. Grand Canyon exactly. So
Speaker 1: you're talking about, Yeah, I forgot the Grand Canyon Park
Speaker 1: So you know how I said the Earth was dynamic, baby, Yeah, Uh,
Speaker 1: that's important. I didn't just throw that in there as
Speaker 1: a factoid. It's important because when these plates shift around,
Speaker 1: that's how fossils are. On Earth. Things can be moved
Speaker 1: great distances and pushed to the surface eventually or close
Speaker 1: enough to where a dig can unearth it. And it's like,
Speaker 1: just because it's fossilized doesn't mean it's stuck in that
Speaker 1: one spot forever, because Earth is always moving. So the
Speaker 1: point of all this is is sedimentary rock um is,
Speaker 1: like you said, dynamic. It moves around. Sometimes fossils pop
Speaker 1: up or it becomes exposed all of the Colorado River um,
Speaker 1: and that is where fossils are, right Chuck. Yes, So
Speaker 1: let's say that at some point in time there was
Speaker 1: a dinosaur or a sabertooth tiger or a cyanobacteria woly
Speaker 1: mammoth wooly mammoth, sure um, and it's um hanging out
Speaker 1: around a riverbed and it has a massive heart attack
Speaker 1: and falls over in the river bed and very quickly
Speaker 1: it becomes covered with sediment and silt, right Yeah, And
Speaker 1: that's important because once it starts getting covered up with stuff,
Speaker 1: it's sort of being protected from like all of fossil.
Speaker 1: Let's just break the news. All of fossil means is
Speaker 1: that something has been protected from the natural decomposition process.
Speaker 1: Otherwise we just decompose like everything else, and you wouldn't
Speaker 1: see it anymore. You've just totally betrayed Tracy in the
Speaker 1: tone she lent to this, that the whole drama drawing
Speaker 1: out suspense. But that's true. So what you said was right.
Speaker 1: So you'd fall over in a riverbed, you start getting
Speaker 1: covered up with the sediment and silt, and it's it's
Speaker 1: immediately starting to protect you in a way. Um, not you,
Speaker 1: but whatever, the wooly mammoth, the wooly mammoth. Um. The
Speaker 1: thing is the in this sediment, in this silt, you
Speaker 1: can't really hide from macrobacteria, uh and other forms of
Speaker 1: life that are basically dedicated to breaking down organic matter,
Speaker 1: soft tissue, hair, eyeballs, um, genitalia, all that kind of stuff.
Speaker 1: It eventually becomes broken down and what's left is the
Speaker 1: hard stuff the bone, right, But the bone also has
Speaker 1: organic material within it as well. Yeah, and that'll break down.
Speaker 1: We're talking blood cells, collagen, fat, that's going to break
Speaker 1: down to the key here is the inorganic parts of
Speaker 1: the bone remain intact. And it's the other keyword here's porous. Yeah.
Speaker 1: You take calcium, I imagine for your hips. Yeah, sure, glucosamine, calcium. Sure.
Speaker 1: So what you're doing is, um, you're fortifying the calcium
Speaker 1: that's already in your hips, supposedly, um, because the bone
Speaker 1: is made in large part of calcium, which is a mineral,
Speaker 1: which is inorganic. So it's all the organic stuff dies out.
Speaker 1: What's left is, like you said, the inorganic like calcium, whatever, minerals,
Speaker 1: and that holds the shape, right, Yeah, the initial structure
Speaker 1: is kept intact. Right, But like you said, this bone
Speaker 1: is also porous. That's the key. And over time, um,
Speaker 1: other mineral sediment kind of um, it enters into these
Speaker 1: these microscopic pores iron right, carbonate yea and fortifies this,
Speaker 1: ultimately turning this but what was once an organic bone
Speaker 1: into an inorganic rock in the shape of the bone.
Speaker 1: But for all intensive purposes, it's still the bone. It
Speaker 1: still has that original calcium. It's still the same thing.
Speaker 1: It's not like a replica of it. It's just become fossilized. Yeah,
Speaker 1: and Tracy in the article uses a pretty good example.
Speaker 1: I thought, it's like filling a sponge with glue. The
Speaker 1: sponge is gonna keep the shape, but the glue is
Speaker 1: gonna ooze through all the spots that it can ouze harden,
Speaker 1: and there you go. You've got a hard sponge, hard sponge,
Speaker 1: which is basically what a fossil is. And this takes
Speaker 1: place Josh over the course of millions of years, the
Speaker 1: sediment reinforcing the bones eventually becoming rock. It's not the
Speaker 1: kind of thing that happens willy nilly over thousands of years.
Speaker 1: It's a long time, and it's just this isn't just
Speaker 1: um happening by itself. All of the surrounding area UM
Speaker 1: is being deposited with sediment as well. It's also turning
Speaker 1: into rock um. And then the ultimate test of time
Speaker 1: for a fossil is that it can withstand the pressure
Speaker 1: of the that's mounted by the hardening rock sedimentary rock
Speaker 1: that's growing around it, so it can be crushed. Is
Speaker 1: that how A lot of fossils are definitely crushed, crushed
Speaker 1: the death poor guys um. But if it survives and
Speaker 1: you can find this, you will eventually be able to
Speaker 1: get to it. And then you remove the rock from
Speaker 1: around the fossil, and there's your bone that you can
Speaker 1: take to the Natural History Museum and get at least
Speaker 1: five dollars for when you were a kid, Josh, let
Speaker 1: me ask you this. Did you ever go into the
Speaker 1: woods on a little nature course from like a science center,
Speaker 1: let's say, and do a cast plaster cast of a
Speaker 1: animal footprint? Did you ever do that? No? Really, really,
Speaker 1: I did that. We went and found like deer hoof prints,
Speaker 1: you fill it with plaster, and there was some way
Speaker 1: of doing it where you an inverse plaster cast of
Speaker 1: a deer hoof print. That can happen actually in a
Speaker 1: way that with trace fossils, so you can you know,
Speaker 1: sediment can act the same way. And one of these,
Speaker 1: let's say, uh, the wooly mammoth makes a footprint in
Speaker 1: some loose but sturdy soil that fills up with sediment
Speaker 1: and creates basically a mold, just like I did as
Speaker 1: a kid with the plaster cast. Yeah, as long as
Speaker 1: the sediment that fills it in is lighter or thinner, yeah,
Speaker 1: than the soil that the impression is made in, then yeah,
Speaker 1: it would it would, it would preserve that track. Yeah,
Speaker 1: and plants can do the same thing. It's not just
Speaker 1: bones we're talking about. Um. It can also fill in
Speaker 1: in a different way, I guess the opposite way to
Speaker 1: where it makes a basically a cast of the foot
Speaker 1: that made the track. Oh yeah. And then so it's
Speaker 1: like a kind of like a fossil of a ghost
Speaker 1: foot that's not really there, but it makes the foot.
Speaker 1: It's like an inverse cast. Okay, yeah, of not the track,
Speaker 1: but the foot that made the track. Yeah. Yeah, got cool.
Speaker 1: You know what other another my favorite trace fossil is
Speaker 1: it's not a track way, it's copper light. I changed
Speaker 1: my mind. That is a good one. That's dunge. It's poop,
Speaker 1: fossilized poop. That's right. I can tell you a lot
Speaker 1: about an animal. It can tell you about its fiber intake.
Speaker 1: It can tell you about what size it's poop was, um, chuck.
Speaker 1: You know. In the eighties, the CIA found out much
Speaker 1: about Gorbachof and his health. They found out he had
Speaker 1: like cancer or some sort of chronic illness um by
Speaker 1: stealing his poop when he was when he came on
Speaker 1: a state visit to the US. They took his poop
Speaker 1: and analyzed it, and when they he was in the US,
Speaker 1: they des grabbed it from the toilet. Did he not flush?
Speaker 1: I just want more specifics. You probably don't have. As
Speaker 1: far as I understand, they probably it's hotel room or
Speaker 1: wherever he was staying. They were prepared to do this.
Speaker 1: This was like toilet rigged. Probably, yes, But wherever Reagan went,
Speaker 1: they had a portable toilet that he used. It was
Speaker 1: the only one he was allowed to use. I'm not kidding,
Speaker 1: so no one could steal his poop. Talk about paranoid. Yeah, seriously,
Speaker 1: when you point one finger, there's three pointing back at you.
Speaker 1: You know what I mean? Yeah? Yeah? Uh so, Josh,
Speaker 1: that is sedimentary rock and that's to me one of
Speaker 1: the cooler ways you can get a fossil. Uh petrified
Speaker 1: would too? Don't leave that one out. Oh yes, it's
Speaker 1: basically the same thing that we just described for bone,
Speaker 1: but for wood. Yeah, hard as a rock because it
Speaker 1: is a rock. Here you go, alright, So, like I
Speaker 1: just said, um, that was sedimentary rock and that's kind
Speaker 1: of fun. But you can also uh get a fossil.
Speaker 1: Has that funny because one dies in a cave that's
Speaker 1: really dry. Yeah, desiccation. Yeah, desiccation is basically, uh, sort
Speaker 1: of a mummification, but it's not like we think of
Speaker 1: with mummification with the Egyptian tombs or anything like that. Well,
Speaker 1: that's because there's no reservation techniques that have been undertaken.
Speaker 1: It's natural. Basically, it dries out. It's like throwing an
Speaker 1: orange in a dehydrator. So when it's really dry, there's
Speaker 1: not gonna be any place for bacteria to thrive. That's
Speaker 1: the reason beef jerky is not um refrigerated. If you
Speaker 1: refrigerate your beef jerky, you're you're doing something wrong. Yeah,
Speaker 1: that's true. Well, if you have beef jerky long enough
Speaker 1: to need refrigeration, then you're doing something wrong or something
Speaker 1: really really right. Uh. So desiccation actually works so well
Speaker 1: sometimes that it can preserve the skin and soft tissues
Speaker 1: as well, which is something that sedimentary rock cannot do.
Speaker 1: Have you been to the Smithsonian I have they have
Speaker 1: um a very cool I guess a prehistoric cow or
Speaker 1: a musk ox I can't remember, but it's the thing's head, um,
Speaker 1: much of its back, I guess, the cape, two of
Speaker 1: its legs, and the skin is still there. It's just
Speaker 1: right there. Probably it's tens of thousands of years old
Speaker 1: and it's just sitting right there. Did they could they
Speaker 1: read build it or just put the parts up? It's
Speaker 1: just the parts, but it's laid out so that like
Speaker 1: it gives you the impression of what you're looking at,
Speaker 1: but its face is still there. It's very cool. Uh.
Speaker 1: My favorite kind of fossil, though, Josh, is I'm gonna
Speaker 1: say that, like every five minutes is a frozen fossil,
Speaker 1: because if you get trapped, let's say your wooly mammoth
Speaker 1: trapped in ice, not only is that going to keep
Speaker 1: other like vultures and things from picking up your bones
Speaker 1: and skin, but it's also going to keep it from
Speaker 1: breaking down and you can get hair fully preserved sometimes
Speaker 1: if you're in skin and like a big mammoth. Have
Speaker 1: you seen pictures of Liuba? Now? Liuba is a baby
Speaker 1: wooly mammoth that was found um by a reindeer herder
Speaker 1: in Siberia and um it was pounds or something like that,
Speaker 1: but it would have gotten up to several tons. It
Speaker 1: is adorable because it is a fully preserved wooly mammoth
Speaker 1: baby with the wrinkles in the skin and everything. Yet
Speaker 1: it spent forty five years in the permafros, but it's
Speaker 1: like completely intact. It's very cute. That's why it's my favorite.
Speaker 1: It's one of the cutest dead things you'll ever see.
Speaker 1: Another couple of ways you can get a fossil josh,
Speaker 1: which are not my favorite aur tar librea tar pits,
Speaker 1: although that is one of my favorites, which librea tar
Speaker 1: pit is actually redundant because Librea means the tar, so
Speaker 1: it's calling it the tar tar pit and not the tartar.
Speaker 1: Did I ever tell you about when I shot a
Speaker 1: commercial there? Have you? Did you go by there in
Speaker 1: l A? No? I want to. I forgot about it
Speaker 1: when we're there last Well, for those of you haven't been,
Speaker 1: it's right in the middle of Los Angeles, like south
Speaker 1: of Hollywood on Wilson Boulevard, and it's um. The main
Speaker 1: tar pit is uh. Tar pits are fenced off, obviously,
Speaker 1: and they have little recreations. It's it's actually the saddest
Speaker 1: thing you'll ever see. The recreation they have in there
Speaker 1: is of a like I guess it's a mother wooly
Speaker 1: mammoth trapped in the tar trying to get out and
Speaker 1: the father and the baby on shore like howling at her.
Speaker 1: It's awful, but it's still active, like all the tars
Speaker 1: bubbling up and everything. And shot a commercial there once
Speaker 1: and I was on the other side of the property,
Speaker 1: far away from the main pit, and I looked down
Speaker 1: and there was a little mini tar pit, a little
Speaker 1: tar puddle about a foot wide, bubbling right beneath my feet.
Speaker 1: I could have scooped it up with my finger if
Speaker 1: I had been so inclined. Yeah, instead, you're like, that stinks. Well,
Speaker 1: it's just crazy to think that that's still like it's happening. Apparently,
Speaker 1: Um I looked it up. There's um there's like you said,
Speaker 1: main pits that are chained off and that are still
Speaker 1: being excavated. But they have them like in neighborhoods all
Speaker 1: around the area and parks. They're just kind of all
Speaker 1: over the place around there. That's like parts of stone
Speaker 1: Mountain popping up all over the place. We used to
Speaker 1: have We had a big chunk of stone mountain in
Speaker 1: our backyard growing up, all right. For those of you
Speaker 1: don't know, Stone Mountain is the world's largest exposed piece
Speaker 1: of granite, and it is right here in our home state,
Speaker 1: and it takes like thirty minutes to hike, but you
Speaker 1: still get to get to the top and be like
Speaker 1: I just hiked a mountain, which I have, Josh. You
Speaker 1: can also get a pete mossy pete can preserve life forms,
Speaker 1: including human beings like Tolin Man was. It was that
Speaker 1: Toland Man. I don't know about him. How do you
Speaker 1: know all these people people? The first the first um
Speaker 1: multi syllable word I could spell was archaeology. Really, I've
Speaker 1: always been interested in that. I could see that, Yeah,
Speaker 1: Tolin Man. Also, it doesn't you can hate archaeology like
Speaker 1: some people hate art, and you'll still be interested in
Speaker 1: Totland man Um he was. He's found in Denmark. He
Speaker 1: lived years ago and he was murdered, uh sacrificially, they think,
Speaker 1: and cast into the peat bog, which pete is just
Speaker 1: decomposing moss and lots of it, but it has a tendency.
Speaker 1: I think it's anaerobic, so um tissue is preserved really well.
Speaker 1: But it's this guy that they dug up, and he's
Speaker 1: so well preserved that when they found him in the
Speaker 1: nineteen fifties, they called the cops because they thought they'd
Speaker 1: found a murder victim really like a recent one. He
Speaker 1: looks kind of funny, but he's got his whiskers are preserved.
Speaker 1: He's wearing a cap. He still has this the garrett
Speaker 1: around his neck. Um, it's really awesome. So what is
Speaker 1: he dated at? Like three four hundred BC? Is the
Speaker 1: one who was killed and he's wearing a hat yeah, sheepskin,
Speaker 1: leather cap. Yeah, no last chance garage for him? No?
Speaker 1: Well uh? And then my favorite way, Josh, that you
Speaker 1: can get a fossil is uh, you're joking? Did you
Speaker 1: say it again? I did? Is amber? They just keep
Speaker 1: getting better and better, like the movie Jurassic Park. Yeah,
Speaker 1: that's how we get dinosaurs again. Yeah, dino d n A.
Speaker 1: So you found something on on whether or not that's feasible, right, yeah,
Speaker 1: because I always wondered. You know, when you see Jurassic Park,
Speaker 1: you see the little video they made it clearly to
Speaker 1: explain to the movie going audience how this is done.
Speaker 1: It's better than Ellen Page running around. What was that
Speaker 1: movie inception? Um, so the mosquito flies in tree residentry
Speaker 1: resident eventually becomes hard as copal, than it eventually becomes
Speaker 1: inert as amber. You get the little mosquito in there.
Speaker 1: They extracted the dino DNA from the blood of the mosquito,
Speaker 1: filled in the gaps with I think frog DNA, and
Speaker 1: that was all there was to it. And at the
Speaker 1: time I thought boom. But being bon Jovi, yeah, at
Speaker 1: the time, I thought that seems plausible, and it sort
Speaker 1: of is. But I did look up today and there
Speaker 1: was a researcher that was interviewed at the or closer
Speaker 1: to that time. I think that basically debunked it and said,
Speaker 1: we could potentially maybe get some DNA, even though it's
Speaker 1: really fragile and loses his signature really quickly. Even if
Speaker 1: you could get the DNA, he said that you couldn't
Speaker 1: construct a dinosaurs just you can't fill in the blanks
Speaker 1: like that. There's way too many blanks. You have a
Speaker 1: giant frog, yeah, with little tiny arms forearms that Steven
Speaker 1: Spielberg made us belief when you saw those dinosaurs walk
Speaker 1: across that field. That guy can make me believe in anything.
Speaker 1: That aliens came to the American Southwest, that there was
Speaker 1: a World War two, that um each phone home. Yeah,
Speaker 1: good stuff. Though, where are we here, chuck it. We're
Speaker 1: kind of painting this picture where if like you just
Speaker 1: stick a shovel anywhere on the Earth, you're gonna yield
Speaker 1: like all sorts of bones and fossils. Note no, it's
Speaker 1: not um First of all, a mere fraction that I
Speaker 1: don't think could possibly be calculated, because we rely on
Speaker 1: the fossil record to show us what existed back when,
Speaker 1: and it's incomplete. Therefore we've entered to catch twenty two.
Speaker 1: But there's just a mere fraction of all of the
Speaker 1: species and organisms that's ever lived that become fossilized um Like. Basically,
Speaker 1: a perfect storm of chance has to occur for a
Speaker 1: fossil to be created. As we've seen, even when it
Speaker 1: is created, it can still be crushed into oblivion. Um.
Speaker 1: And so there are few and far between. To begin with,
Speaker 1: what we have to figure out where to find them.
Speaker 1: While then you got to find it. That's the other problem.
Speaker 1: And the way we find it is by identifying rock
Speaker 1: that will likely have the type of fossil that we're
Speaker 1: looking for. Yeah, so you want something that from that year.
Speaker 1: So if you know that this animal from yeah, if
Speaker 1: you if you know this this animal lived, you know,
Speaker 1: thirty million years ago, you're gonna go find rock that
Speaker 1: you know is thirty million years old and start poking
Speaker 1: around and you know, looking this sort of a very
Speaker 1: chance thing, and we know that, um, we know, like
Speaker 1: say a layer of rock or strata of rock is
Speaker 1: thirty million years old because of a technique we have
Speaker 1: called radiocarbon dating. Right, yeah, you want to do this one? Well? Sure,
Speaker 1: Carbon fourteen dating is what a lot of people toss
Speaker 1: around because it's probably the most well known, But that
Speaker 1: can only take you back sixty thousand years. We're talking
Speaker 1: millions and billions of years. So they need to uh
Speaker 1: study isotopes like potassium forty and uranian two thirty eight
Speaker 1: because that goes back millions of years. Evidently. The half
Speaker 1: life yeah, and the half life is where an atom
Speaker 1: loses half of its life isotopes to decay. Yeah, okay,
Speaker 1: and these the this um radioactive decay takes place at
Speaker 1: a predictable rate depending on the atom, the type of atom. Right, Yeah,
Speaker 1: that's how I understand it. So if we find a
Speaker 1: type of atom missing x number of isotopes, we can say, well,
Speaker 1: this is roughly thirty million to thirty one million years old,
Speaker 1: or thirty million to thirty million and three hundred years old.
Speaker 1: I'm not sure what window we can date it to, right,
Speaker 1: but I think it's enough so that you know, we
Speaker 1: have a rough estimate of of you know, when this
Speaker 1: fossil lived in the sediment was buried around it. So, Josh,
Speaker 1: let's say that you're lucky enough and skilled enough as
Speaker 1: an intrepid paleontologist to come across your fossil. What do
Speaker 1: you do? Well, as I said, you dig it up
Speaker 1: and take it to the museum and sell it for
Speaker 1: five Smolan Well, I don't know about that, but you
Speaker 1: should call a museum. Even if you think you know
Speaker 1: what you're doing, Uh, you're probably gonna need some help
Speaker 1: if it's something major. I think you should probably go
Speaker 1: on the assumption that you don't know what you're doing
Speaker 1: unless you're a trained paleontologist. Um. Part of the problem
Speaker 1: is is we assume that these fossils, being rocks, are sturdy.
Speaker 1: That's not always the case. So there's a lot of
Speaker 1: danger of damage um in a just an average joe
Speaker 1: trying to excavate him. Also, if you just pull a
Speaker 1: bone up and walk away with it, Uh, it immediately
Speaker 1: loses context. Yeah, it's like removing a piece of evidence
Speaker 1: from a crime scene almost exactly. I can't do that. Well,
Speaker 1: you're not supposed to. Uh. So you know, they have
Speaker 1: these huge cranes and uh digging tools where they can
Speaker 1: remove huge slabs of earth, which is a really good
Speaker 1: way to do it. And sometimes if they're you know,
Speaker 1: if it's something that could be fragile, they will remove
Speaker 1: the entire slab, cast it in plaster and just go
Speaker 1: ahead and ship that thing off to a facility to
Speaker 1: handle it from there. And the cool thing is is,
Speaker 1: even though rock has formed around this bone, yeah, that's
Speaker 1: key right up right, all up on it, all up
Speaker 1: in it. If you um flake it away properly, if
Speaker 1: you flake the surrounding sedimentary rock away, um, you're going
Speaker 1: to find that there's what's called the plane of weakness,
Speaker 1: which is where the bone and the rock are still
Speaker 1: on this very microscopic level. They're not fused together. You're
Speaker 1: gonna hit that and the rock should chip right away,
Speaker 1: right and and leave the bone. Yeah, And I think
Speaker 1: sometimes they missed it with water too, to soften it
Speaker 1: up and help the whole process. Another thing too, if
Speaker 1: they find that is really brittle, they can actually reinforce
Speaker 1: the bone with resin and thin glue. But you need
Speaker 1: to be careful there too, which is pretty much helping
Speaker 1: along the fossilization process. Yeah, I would think so. I
Speaker 1: mean it's the same thing. It's like artificial forcing it
Speaker 1: with something sturdy. Well, and then you can date it
Speaker 1: using your little mass spectrometer that's in your pocket, and
Speaker 1: or a cat scan sometimes they use cat scans computer
Speaker 1: imaging stuff like that. Yeah, I didn't I didn't get
Speaker 1: how they were dating it from cat scan. I don't
Speaker 1: know if they're dating it with a cat scan or
Speaker 1: just sussen the whole thing out. Gotcha. I don't think
Speaker 1: it's a dating situation. Tracy was just throwing out some
Speaker 1: extra tools of the trade. Huh Yeah, exactly, gotcha. So, um, chuck,
Speaker 1: what is all this worth? I mean, we we have
Speaker 1: a thirst for knowledge. Obviously people think bones are very cool,
Speaker 1: But ultimately, what's the pursuit of paleontology to to put
Speaker 1: together the piece of the puzzle of how we got here? Right?
Speaker 1: I mean that's what I think. Yeah, that's my understanding
Speaker 1: as well. Yeah, you can learn a lot by not
Speaker 1: only finding the fossil, but finding what was with the
Speaker 1: fossil in that same strata. Ah, I can tell you, like, hey,
Speaker 1: this is a t rex bone and there's also a
Speaker 1: bit of pine tree, so we know pine trees were around,
Speaker 1: and they may have eaten pine trees while not the
Speaker 1: t rex because they were carnivores, right, Um, yeah, they
Speaker 1: were herbivore. Let's say, you know what I mean, Abronosaurus. Sure. Um.
Speaker 1: And ultimately all of these fossils come together, plant and well,
Speaker 1: everything that we can get our hands on to form
Speaker 1: what is called the fossil record, right, and this is
Speaker 1: basically the record of life on Earth. Uh. It's also
Speaker 1: used to support evolution big time. And uh it's here
Speaker 1: that paleontology gets most contentious, right yeah, sure, because there's, um,
Speaker 1: the the idea that beings evolved if you go far
Speaker 1: enough back from a single common ancestor, right. And so
Speaker 1: if we can put together a complete fossil record, we
Speaker 1: would be able to see how everything alive today evolve
Speaker 1: from this common ancestor or common ancestors. Right. Yeah. The
Speaker 1: problem is fossil records incomplete, and one of the really
Speaker 1: key parts that it's often missing are called transitional fossils. Right.
Speaker 1: My favorite kind of fossil, Josh is a transitional fossil.
Speaker 1: And one example Tracy used was the baleen whale. Uh.
Speaker 1: There there's a picture of one actually in the article
Speaker 1: twenty five million year old fossil of of the baleen
Speaker 1: whale with sharp teeth. Um. Today's bailing whales don't have
Speaker 1: sharp teeth, but we know that once before this had
Speaker 1: sharp teeth and legs. So this is a transitional fossil
Speaker 1: that shows, well, they used to have legs and sharp teeth,
Speaker 1: then they just had sharp teeth, and now they don't
Speaker 1: have legs or sharp teeth. They're defenseless, which is why
Speaker 1: they're baling whales, right and not sharks or megalodon's right. Um.
Speaker 1: And so a transitional fossil is one that that pops
Speaker 1: up between old and new, and it makes sense. Our
Speaker 1: understanding of evolution is that it takes a little while,
Speaker 1: and um, something like teeth aren't just gonna go away
Speaker 1: in one generation. It's gonna take more and more and more,
Speaker 1: and then um, we should be able to find them
Speaker 1: along the way where maybe the teeth gets smaller. There's
Speaker 1: fewer and fewer um baling whale teeth in the average
Speaker 1: baling whale mouth, and you're putting together the puzzle exactly. UM. Again,
Speaker 1: the fossil records a little incomplete, and there aren't as
Speaker 1: many transitional fossils as I think people would like to.
Speaker 1: UM have tied all together, right, UM, and then some
Speaker 1: of the UH. Some of the explanations are Probably the
Speaker 1: most famous explanation for this is that UM evolution isn't gradual.
Speaker 1: I think it's Stephen J. Gould came up with the
Speaker 1: idea of punctuated equilibrium, and that is basically that UM
Speaker 1: evolution takes place suddenly in these huge quick fits and starts,
Speaker 1: which would explain why there's not like teeth don't go
Speaker 1: away in a generation, but they go away a lot
Speaker 1: faster than we used to suspect. And that's why these
Speaker 1: UM fossils UM, accompanied with the idea that not every
Speaker 1: animal that's ever died has become fossilized, explained why there's
Speaker 1: huge gaps in the fossil record, which will inevitably always
Speaker 1: be incomplete. Is that a hypothesis at this point? I
Speaker 1: guess it is not a theory yet I don't. I
Speaker 1: don't think so. I think it is a hypothesis. I
Speaker 1: got one more thing, Okay, I'd like to finish with
Speaker 1: my favorite kind of fossil, and that is a living fossil.
Speaker 1: And that, Josh, is when you've got a plant or
Speaker 1: animal that looks so much like ancient fossils that they
Speaker 1: consider a living fossil. Allah, the horseshoe crab. Right, apparently
Speaker 1: the horseshoe crab has not changed. Didn't need too. It's perfect.
Speaker 1: I look at it, it's gorgeous. What else, oh, Genko
Speaker 1: baloba plants. And then a word that I don't know,
Speaker 1: the Cela cant. What is that? Uh, it's this horrid
Speaker 1: looking fish that they remember that VW commercial where he's
Speaker 1: like it's like the Ceila camp and the guys like
Speaker 1: what they're looking in the trunk and he's like a
Speaker 1: full size spare tire. He's like, it's like a Ceila cant.
Speaker 1: They used to think it was extinct. There was a fish,
Speaker 1: and then they found it like in the nineteen thirties again.
Speaker 1: But it's this dinosaur looking fish. Oh, I think I've
Speaker 1: seen him that they thought was extinct for millions of
Speaker 1: years and they called him and I think in South America,
Speaker 1: off the coast of South America, and they're still around.
Speaker 1: And the horseshoe Crab and Stephen J. Gould in the
Speaker 1: Genko Baloba. Well, it's it for fossils, right, that's all
Speaker 1: I have. I think we've got the point across. It's
Speaker 1: an overview. A fossil is a rock. Just remember that,
Speaker 1: Okay if you want to learn more about fossils. Um Seriously,
Speaker 1: this is one of the better articles on the site.
Speaker 1: Tracy did a great job with it. Type fossils into
Speaker 1: the search bar, the handy search bar, and how stuff
Speaker 1: works dot com, which means it's time for listener mail. Josh,
Speaker 1: we made a young girl cry. That's what I'm gonna
Speaker 1: call this one. Okay, It's probably happened more than once.
Speaker 1: Uh I, guys and Jerry. My name is Ali. I'm
Speaker 1: from Indiana. I was in the I S s M,
Speaker 1: a band contest, playing a difficult marimba solo today. I
Speaker 1: was pretty nervous, but being first chair and the only
Speaker 1: female percussionist in my school really brought up my confidence.
Speaker 1: I went in, I choked, and I stumbled through my piece.
Speaker 1: You could get a gold, silver bronze, or a participation metal.
Speaker 1: Got the bronze, which is equivalent to a score of
Speaker 1: an F. I was really upset. Wait, what is participating?
Speaker 1: That's sub f I didn't even know they made medals.
Speaker 1: I thought it was just a ribbon. It's probably a ribbon.
Speaker 1: I was really upset. I got home. I was trying
Speaker 1: to cheer myself up by listening to your podcast on
Speaker 1: What's the Deal with Stinkholes. I really love the show,
Speaker 1: and I've listened almost everyone, But in the beginning, you
Speaker 1: guys talked about how much the Bronze medals suck. Remember that.
Speaker 1: Oh yeah, so we didn't lift spirits very much, Josh
Speaker 1: and Chuck. I just want to let you know that
Speaker 1: the two of you made me cry then from Ali
Speaker 1: and I have since written Alie back and apologized, and
Speaker 1: she said that she's feeling much better now and uh,
Speaker 1: it wasn't our fault. And I told her that I've
Speaker 1: choked under pressure many times in my life and it happens,
Speaker 1: and it will happen again, and it doesn't mean you
Speaker 1: don't have the goods with your solo every single time. Yeah,
Speaker 1: but you know you pick yourself up. It sounds like
Speaker 1: you gave her some good advice to choke. I think
Speaker 1: so she's getting receptive to it. It's like a sweet girl.
Speaker 1: I think that's an excellent lead in. If you have
Speaker 1: a story about choking, not physically choking, but you there's
Speaker 1: something you're good at and you didn't do it. Well,
Speaker 1: say you're a television reporter in Los Angeles and you're
Speaker 1: supposed to report on the Grammys like that. So you're
Speaker 1: a podcaster and you have to do a show about
Speaker 1: the sun to give one too, but we want to
Speaker 1: hear about it. You can send it to us via email.
Speaker 1: Just type in where it says to stuff podcast at
Speaker 1: how stuff works dot com. For more on this and
Speaker 1: thousands of other topics, does it how stuff works dot com.
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