Latest / Stuff You Should Know / Selects: How Extinction Works

Transcript

Selects: How Extinction Works · Stuff You Should Know

0:00
Speaker 1: Hello friends, It's Josh and I'm back with the Select
0:04
Speaker 1: and this week I've selected our twenty fourteen episode on extinction.
0:09
Speaker 1: In this episode, we go over all the big extinctions
0:12
Speaker 1: and what probably caused them, including the one we're most
0:16
Speaker 1: likely in right now, which was probably caused by humans.
0:20
Speaker 1: And if you pay attention, you can start to notice
0:22
Speaker 1: a little glimmers, a little beginnings of what would become
0:25
Speaker 1: my side podcast, The End of the World with Josh Clark.
0:29
Speaker 1: And although we don't talk about any movies, I'm betting
0:31
Speaker 1: there's some glimmers of Chuck's long running side podcast movie
0:35
Speaker 1: Crush in here too. Hope you enjoy this episode. It's
0:39
Speaker 1: a good one.
0:44
Speaker 2: Welcome to Stuff you should know, a production of iHeartRadio.
0:54
Speaker 1: Hey, and welcome to the podcast. I'm Josh Clark, There's
0:57
Speaker 1: Charles W. Chuckers Bryant. Jerry is over there. I'mosa said
1:01
Speaker 1: your last name, Jerry, how weird. And then today we
1:04
Speaker 1: have a fourth character in the in the studio with
1:07
Speaker 1: this Chuck. This a cent, yeah, scent coming together to
1:13
Speaker 1: make like a tangible human being. So you are wearing Petuli,
1:18
Speaker 1: uh not wearing well, you have Petulia on you as
1:21
Speaker 1: a result of one of Emily's sugar scrubs right from Mama. Yeah,
1:26
Speaker 1: and it's love Yourmama dot Com. Yeah, okay, and then
1:29
Speaker 1: Jerry is contributing to that with an enchilada. So all
1:35
Speaker 1: of them combined, I would say, there's like there's an
1:38
Speaker 1: extra person in the seat right here. Uh, what kind
1:41
Speaker 1: of person is that? Just another person? Okay, a viable
1:44
Speaker 1: living organism, one that when we leave the studio will
1:51
Speaker 1: probably become extinct. That's a good one. Did you like that? Yeah,
1:56
Speaker 1: I've had that plan since probably two weeks ago. Nice.
2:01
Speaker 1: How are you doing, man, I'm good.
2:04
Speaker 2: I've been thinking of Buster Rhymes all day.
2:06
Speaker 1: Why did he have a song about extinction?
2:08
Speaker 2: He had an album called Extinction Level Event. Oh yeah, yeah,
2:12
Speaker 2: and that was in one of the songs.
2:14
Speaker 1: That sounds super nineties.
2:16
Speaker 2: Well it's Buster Rhymes, it has to be nineties.
2:18
Speaker 1: But I mean even those words extinction level Event. People
2:22
Speaker 1: were worried about stuff because of like the Turn of
2:24
Speaker 1: the Millennium, you remember, is a huge hit. Sure, Deep
2:29
Speaker 1: Impact and Armageddon came out like on the same day basically,
2:34
Speaker 1: and both were hits. Like people were just nervous. Yeah,
2:38
Speaker 1: And as a result, Buster Rhymes was very popular. That's right.
2:43
Speaker 2: Although he's not anymore, he's still good though he hadn't
2:47
Speaker 2: been doing much.
2:49
Speaker 1: No, but his body of work is oh for sure. Yeah,
2:52
Speaker 1: leaders in the New School and his early work with
2:56
Speaker 1: Trip Call Quest.
2:57
Speaker 2: Oh yeah, he guessed it on one of my favorite songs.
2:59
Speaker 1: Yeah, what's the scenario? Was that the one? I think? So?
3:04
Speaker 1: I mean, it was definitely on that one. Yeah, but
3:06
Speaker 1: they that was the one also where I think, Yeah,
3:10
Speaker 1: he makes fun of people with saggy pants because it
3:13
Speaker 1: was so new. Apparently Buster Rhymes wasn't down with it yet, yeah,
3:17
Speaker 1: which is pretty ironic because he got hardcore into that.
3:20
Speaker 2: That was like a dungeon dragon, right right, right, that's
3:24
Speaker 2: pretty awesome.
3:24
Speaker 1: It's a good song. Yeah. So extinction is clearly what
3:28
Speaker 1: we're talking about today. Uh and uh, I guess we
3:33
Speaker 1: should probably give a shout out to some of the
3:34
Speaker 1: extra reading material. Yeah, man, we picked up on There's
3:38
Speaker 1: a woman named Elizabeth Colbert or Colbert depending on what
3:45
Speaker 1: if you watch The Colbert Apoor and she is basically
3:50
Speaker 1: a leading expert as far as journalists go on extinction.
3:55
Speaker 1: She wrote a book called The Sixth Extinction. That's it's
3:57
Speaker 1: a good article. Yeah, and like they she wrote an
4:00
Speaker 1: article in the New York or she's a New Yorker
4:02
Speaker 1: journalist that was basically the predecessor to the book, you
4:05
Speaker 1: know how they do. Sure, They're like, oh, I need
4:06
Speaker 1: an extra twenty grand, so I'll just write a synopsis
4:09
Speaker 1: of the book I'm writing. Yeah, And it's a good article,
4:12
Speaker 1: and we work from that. There's another one from the
4:15
Speaker 1: New York Review of Books called They're taking Over about
4:18
Speaker 1: the explosion of jellyfish. On How Stuff Works, there's one
4:22
Speaker 1: that I wrote years back called will We Soon Be Extinct?
4:26
Speaker 1: And there's another House Stuff Works one that we've done
4:28
Speaker 1: an episode on called why is Biodiversity Important? Yeah?
4:32
Speaker 2: And I found one in an Io nine h huh
4:35
Speaker 2: for animals that we thought were extinct but miraculously pop.
4:40
Speaker 1: Back up nice. Which it's always a good story. Oh yeah,
4:44
Speaker 1: it's a heartwarming story of triumph of diversity and coming
4:49
Speaker 1: back when everybody thought you were down.
4:51
Speaker 2: Yeah, some of them like basically rocky, hundreds of millions
4:53
Speaker 2: of years later. Even Yeah, it's crazy, like the silicamt
4:58
Speaker 2: I think that's when it was at the Big Fish. Yeah,
5:02
Speaker 2: they just caught that thing one day. Yeah, and said, hey,
5:06
Speaker 2: wait a minute, Yeah, this thing's extinct.
5:09
Speaker 1: It's supposed to be, and we'll talk about how and
5:12
Speaker 1: why things fall off. But things do fall off, and
5:17
Speaker 1: it seems that there is a that the whole thing
5:21
Speaker 1: is a very natural process. Extinction is. But for a
5:25
Speaker 1: very long time, I guess, scientists believe that the God
5:33
Speaker 1: created all of the animals yeah on Earth, and that
5:38
Speaker 1: his will was too perfect, his creation was too divine
5:41
Speaker 1: to even allow for extinction. So because they were aware
5:45
Speaker 1: of the fossil record, they rationalized these huge bones of
5:49
Speaker 1: animals they didn't see anywhere as we just haven't found
5:51
Speaker 1: them yet.
5:52
Speaker 2: Well yeah, and this was all the way up and
5:54
Speaker 2: you know, into the nineteenth century, and some really smart
5:56
Speaker 2: people like Thomas Jefferson thought, for instance, when he sent
6:00
Speaker 2: Lewis and Clark out west, that they might come across
6:03
Speaker 2: the great Mastodon. Right, He's like, it's found to be
6:06
Speaker 2: out there somewhere, guys, to be careful. But there were
6:09
Speaker 2: some other smarter people like George Cuvier in eighteen twelve,
6:14
Speaker 2: he was pretty ahead of his time. In fact, in
6:16
Speaker 2: eighteen twelve he was way ahead of his time because
6:19
Speaker 2: he published an essay called revolutions on the surface of
6:22
Speaker 2: the globe, and he kind of asserted that now things
6:26
Speaker 2: can go extinct, and he called them a species perduce
6:31
Speaker 2: lost species and basically hypothesize that there have been cataclysmic
6:37
Speaker 2: events that have caused extinctions.
6:40
Speaker 1: Right. In so many words, this is basically flew in
6:43
Speaker 1: the face of this that not only was their extinction,
6:46
Speaker 1: but there were huge events that caused it. And so
6:50
Speaker 1: the religious thinkers of the day said, okay, wait, wait, wait,
6:52
Speaker 1: we can work with this, because buddy, what you're talking
6:55
Speaker 1: about is like Noah's flood. So you, my friend, just
7:00
Speaker 1: the Bible correct using science.
7:02
Speaker 2: Yeah, Darwin wasn't on board though, although he did believe
7:05
Speaker 2: in extinction, he thought it was the only way it
7:07
Speaker 2: could happen is the gradual extinction.
7:10
Speaker 1: Right, That is also true, and we'll talk about that
7:12
Speaker 1: as well. And of course Darwin is this huge hero
7:14
Speaker 1: of biology, so everybody's like, well, Darwin's right about just
7:18
Speaker 1: about everything. So literally, until the nineteen nineties, Darwin's view
7:25
Speaker 1: that extinction happens extremely slowly, slower than speciation events, so
7:30
Speaker 1: ultimately you should always have more species new species coming
7:35
Speaker 1: up than you have going extinct. Until the nineteen nineties.
7:39
Speaker 1: That's the way that it was, That's the way it seemed. Yeah,
7:42
Speaker 1: So Chuck, like I said, all of this stayed around
7:46
Speaker 1: until nineteen ninety one. Yeah, and it was a result
7:49
Speaker 1: of like, think about it, think about how you think
7:51
Speaker 1: of mass extinctions. Now, you think of an asteroid hitting Earth,
7:57
Speaker 1: destroying everything. And it wasn't until nineteen ninety one that
8:01
Speaker 1: that view became widely accepted. And it was because of
8:05
Speaker 1: this dude named Alvarez. He was a geologist, I believe,
8:10
Speaker 1: Walter Alvarez, and in the seventies he started studying this
8:13
Speaker 1: clay layer that was basically in the fossil record right
8:18
Speaker 1: at the time the dinosaur suddenly died out right, and
8:21
Speaker 1: no one could quite explain what was going on here.
8:23
Speaker 1: They just knew that this must have happened gradually, so
8:27
Speaker 1: it must be a problem with the actual fossil record,
8:30
Speaker 1: not our way of thinking.
8:31
Speaker 2: Yeah, and there are plenty of problems with the fossil record,
8:33
Speaker 2: which we'll get into as.
8:34
Speaker 1: Well, right, But Walter Alvarez said, let me look at
8:38
Speaker 1: this in a little more detail, and he looked at
8:40
Speaker 1: the iridium and found that the iridium levels were off
8:43
Speaker 1: the charts. Which shouldn't be because it's very very rare,
8:46
Speaker 1: and we associate iridium on Earth as being brought here by, say,
8:49
Speaker 1: like an asteroid or whatever.
8:51
Speaker 2: Yeah, it's superabundant asteroids.
8:53
Speaker 1: So all of a sudden, this guy goes, oh, wait
8:55
Speaker 1: a minute, maybe we can explain this dying out of
9:00
Speaker 1: dinosaurs where the dinosaurs went sixty five million years ago
9:03
Speaker 1: by an asteroid. And that was in nineteen eighty that
9:06
Speaker 1: they proposed a hypothesis, and they ran into a lot
9:09
Speaker 1: of resistance, and then finally in nineteen ninety one, a
9:15
Speaker 1: year after a crater was discovered under the Yucatan Peninsula
9:19
Speaker 1: in Mexico, they dated it and said, yeah, it just
9:24
Speaker 1: so happens that this crater was formed just at the
9:27
Speaker 1: moment the dinosaurs died out. So yeah, the Alvarez hypothesis
9:30
Speaker 1: is probably right, and extinction can happen on a mass
9:34
Speaker 1: sudden scale, just as it can also happen on a
9:37
Speaker 1: very long term scale too.
9:39
Speaker 2: Yeah, that crater was one hundred and twelve miles wide,
9:41
Speaker 2: so it fit the profile and basically ended the Cretaceous
9:46
Speaker 2: period in the Mesozoic era, and for a while they
9:49
Speaker 2: called it the Cretaceous Tertiary event. But now they call
9:53
Speaker 2: it the Cretaceous Paleogene event.
9:56
Speaker 1: And did you notice that thing KPg right, they noticed that.
10:00
Speaker 1: Did you notice the Cretaceous, which is spelled with the
10:03
Speaker 1: sea is denoted with a K? Yeah? Did you see why?
10:07
Speaker 1: It's just German? It's just a German translation for it.
10:10
Speaker 1: I figured it was something like that. Yeah, it was
10:13
Speaker 1: just bugging me.
10:14
Speaker 2: So now we now believe an asteroid brought us into
10:17
Speaker 2: the Cinazoic era that we that we enjoyed today.
10:21
Speaker 1: Love the Sinazoic. It's pretty good, pretty awesome. It's a
10:23
Speaker 1: good era. I mean, it's our era. Yeah, you gotta
10:26
Speaker 1: love it. You gotta love it. So Chuck, like I said,
10:31
Speaker 1: the extinction, extinction can happen, and it does happen, and
10:35
Speaker 1: it's a natural process. If you talk to people about
10:39
Speaker 1: extinction today, though, they say, yeah, we're kind of in
10:44
Speaker 1: a huge extinction event.
10:47
Speaker 2: Yeah, and it makes sense. I mean when you look
10:48
Speaker 2: at our past. They estimate maybe up to five billion
10:53
Speaker 2: species have lived on Earth, and more than ninety nine
10:56
Speaker 2: percent of those are gone.
10:57
Speaker 1: And I love how the New Yorker put it.
10:59
Speaker 2: I think that there's an old joke that all of
11:02
Speaker 2: life on Earth today could be accounted for with a
11:04
Speaker 2: simple rounding error.
11:05
Speaker 1: Yeah, like everything we know.
11:09
Speaker 2: So, yeah, we've lost ninety nine percent of things that
11:11
Speaker 2: have ever lived on this planet due to extinction.
11:14
Speaker 1: Right, which again is like it has such a terrible
11:17
Speaker 1: connotation these days, extinction, extinction, but it happens naturally. Apparently.
11:22
Speaker 1: What they've found from looking at the fossil record from
11:25
Speaker 1: studying life on Earth is that a species tends to
11:29
Speaker 1: have about a ten million year lifespan, and the a
11:33
Speaker 1: speciation event occurs where it branches off from one specie
11:37
Speaker 1: and produces an entirely new species, and that species on
11:40
Speaker 1: average will stick around for about ten million years and
11:43
Speaker 1: then something happens and it dies out and other species
11:48
Speaker 1: take its place. This is the natural course of life
11:51
Speaker 1: from what we can tell. The thing is, it normally
11:54
Speaker 1: happens on a very slow time scale, like when it's
12:00
Speaker 1: so what it's called background extinction, right.
12:02
Speaker 2: Yeah, the background rate is supposed to be between one
12:05
Speaker 2: and five species per year, but they think that now
12:08
Speaker 2: it could be like one hundred times that.
12:10
Speaker 1: I've seen up to a thousand times the normal rate,
12:14
Speaker 1: And I saw another study from twenty fourteen, so it's
12:17
Speaker 1: fresh and it said that they these researchers calculated the
12:22
Speaker 1: normal rates and they found that there's between point zero
12:25
Speaker 1: two to three and point one three five extinct species
12:29
Speaker 1: per million species per year. That doesn't really mean much.
12:35
Speaker 1: It means so much that it boggles the mind. Yeah,
12:37
Speaker 1: you know, like that's a really strange way of putting it.
12:40
Speaker 1: But basically they're saying, like, for every million species on
12:43
Speaker 1: Earth at any given point in time during a year,
12:47
Speaker 1: as low as point zero two three species will die out.
12:52
Speaker 1: So in a year you shouldn't necessarily have that main
12:54
Speaker 1: species in current times though, like you said, between a
13:00
Speaker 1: one hundred and a thousand times that rate is what
13:02
Speaker 1: we're seeing right now, which is you could say, alarming.
13:06
Speaker 1: It is alarming.
13:07
Speaker 2: The reason they don't have hard numbers on this stuff
13:09
Speaker 2: is because, like we said, it's a tough thing to study,
13:12
Speaker 2: because the fossil record is well, there's a lot of problems.
13:16
Speaker 2: One is it's incomplete. We don't really know how many
13:20
Speaker 2: fossor species have been on Earth since the beginning of Earth.
13:25
Speaker 2: It's just impossible to tell fossil's forum under really specific conditions.
13:30
Speaker 2: So you may think something is gone because it has
13:34
Speaker 2: disappeared from the fossil record. But all that means is
13:37
Speaker 2: there wasn't a fossil. It doesn't necessarily mean it's gone right,
13:40
Speaker 2: So that's why things will pop back up that they'll think, hey,
13:43
Speaker 2: we haven't seen a fossil of this guy in two
13:45
Speaker 2: thousand years, but here it is all of a sudden.
13:47
Speaker 1: And even if it has gone extinct, just where it
13:51
Speaker 1: stopped showing up in the fossil record doesn't mean, like
13:54
Speaker 1: you said, that's when it went extinct, right, then it
13:57
Speaker 1: could have been millions of years later.
13:59
Speaker 2: Well, because then you're supposed that the last thing of
14:01
Speaker 2: that species happened to make a fossil.
14:03
Speaker 1: Yes, which is just silly. Yeah, and also it makes
14:06
Speaker 1: you wonder how many species have lived and died on
14:08
Speaker 1: Earth that just never showed up in the fossil record. Yeah,
14:12
Speaker 1: just weren't fossils at all. Right.
14:13
Speaker 2: Yeah, Well, if it never crawled into amber or you know,
14:17
Speaker 2: was buried by ash or something, that's luck.
14:21
Speaker 1: Or got trapped in Bronosaurus poop. I don't know if
14:24
Speaker 1: that's good luck or bad luck. It's just it is
14:27
Speaker 1: what it is. It's nature.
14:29
Speaker 2: So because of all these gaps in the fossil record,
14:33
Speaker 2: these Researchers that love this topic tend to do a
14:36
Speaker 2: lot of math, right, and a lot of speculating with
14:39
Speaker 2: algorithms and mathematical formulas.
14:42
Speaker 1: They love this stuff out, sure, and that's.
14:44
Speaker 2: The only way to do it, really, to speculate with numbers.
14:48
Speaker 2: It also helps them define things like the minimum viable population,
14:51
Speaker 2: which if you go below that, then it's bad news
14:54
Speaker 2: for the species. It's the minimum amount you can have
14:58
Speaker 2: to still be considered to have a bright future.
15:02
Speaker 1: Right as a thing, or to just survive as a species.
15:05
Speaker 2: Right, Yeah, that's what I mean. Yeah, dim future if
15:09
Speaker 2: you're not surviving.
15:10
Speaker 1: Yeah, math is pretty grim. It can be in this
15:13
Speaker 1: case for sure. So we'll talk about exactly what makes
15:17
Speaker 1: an extinction and then what makes up mass extinctions. But
15:21
Speaker 1: first let's do a little breakage. Huh okay, So, Chuck,
15:38
Speaker 1: you've been talking about animals, animal species going extinct and
15:44
Speaker 1: then showing up again like the Sela cant Yeah, or
15:46
Speaker 1: at least disappearing right from the record, But we as
15:49
Speaker 1: humans assumed they were extinct. Like again, the Sela cant
15:52
Speaker 1: is this fish that they caught off the coast of
15:55
Speaker 1: South Africa. When did we talk about it? Was it
15:57
Speaker 1: end of this day in history. I don't remember. We
15:59
Speaker 1: definitely hit on that though. I think it was because
16:01
Speaker 1: it's huge, right, Yeah, it's a big, ugly fish. Yeah,
16:05
Speaker 1: and it looks like an old dinosaur. But they thought
16:07
Speaker 1: it had died out like like fifty sixty million years ago.
16:12
Speaker 2: Actually way longer. They thought it disappeared four hundred million
16:15
Speaker 2: years ago.
16:16
Speaker 1: Even more impressive. Yeah. So then they caught one off
16:18
Speaker 1: the coast of South Africa in the thirties. Then they
16:21
Speaker 1: caught another one a couple decades later in Madagascar or
16:25
Speaker 1: Mauritius or something, and that made the selacanth a Lazarus species,
16:32
Speaker 1: even though it hadn't really gone anywhere. We just thought
16:35
Speaker 1: it did. So we humans having the most important perspective
16:38
Speaker 1: on the entire planet, possibly in the entire universe. Yeah,
16:41
Speaker 1: it was a Lazarus species to us.
16:43
Speaker 2: Yeah, Lazarus from the Bible, right, raised from the dead. Yeah,
16:46
Speaker 2: like the Seila cant.
16:47
Speaker 1: Again with the Biblical connotations with extinction. Yeah, there's a
16:51
Speaker 1: lot at stake here, that's true.
16:54
Speaker 2: Another way something might disappear and you might think it's
16:57
Speaker 2: gone is if it actually evolves into a new species.
17:00
Speaker 2: That's called pseudo extinction, and that's a great success story
17:04
Speaker 2: as well.
17:04
Speaker 1: It is, but it also I don't understand why that's
17:07
Speaker 1: not just a speciation event. I mean, why is that
17:11
Speaker 1: pseudo extinction? Why is that any different from regular extinction?
17:16
Speaker 2: Yeah, maybe just because it's didn't die out, it actually
17:21
Speaker 2: just changed and evolved.
17:23
Speaker 1: Those are two different things. Yeah, it seems like a
17:25
Speaker 1: gray area to me. Yeah. But for the most part,
17:29
Speaker 1: when an animal just disappears, and we should say, like
17:33
Speaker 1: even today, we're still finding things that we thought were extinct,
17:37
Speaker 1: so called Lazarus species, which goes to make the point
17:41
Speaker 1: we have no idea how many living species there are
17:45
Speaker 1: on the planet today, Yeah, or have been. It's all
17:48
Speaker 1: just a good guess it is using math, yeah, grim,
17:52
Speaker 1: grim math. But for the most part, we understand that
17:55
Speaker 1: when a species goes away, suddenly it went extinct. And
18:00
Speaker 1: as we've been saying again and again, extinction is kind
18:03
Speaker 1: of this natural process, or it is a very natural process,
18:08
Speaker 1: and it typically results from a change in the habitat yeah,
18:14
Speaker 1: of a species, and it's inability to adapt so it
18:18
Speaker 1: dies out.
18:19
Speaker 2: Yeah, competition with other species, hunting by humans, or perhaps
18:25
Speaker 2: the environment has been tainted by humans.
18:28
Speaker 1: Humans or a new bacteria or a new virus. The
18:32
Speaker 1: thing is, though, is so these these big factors, habitat loss,
18:35
Speaker 1: competition with new species, hunting, and contaminous in the environment.
18:40
Speaker 1: Those are the big four reasons that something goes extinct, right, Yeah,
18:43
Speaker 1: Humans can and are responsible for all four of those.
18:48
Speaker 2: Yeah, and the and these are This is the extinction
18:50
Speaker 2: that happens over time. Obviously not a big asteroid hit
18:53
Speaker 2: in the planet.
18:53
Speaker 1: No, but it can't happen pretty quickly. In this this
18:56
Speaker 1: is a Tracy Wilson joint and in the introduction she
19:01
Speaker 1: mentions the stellar sea cow, which was an Arctic resident.
19:06
Speaker 1: It was a big old manatee basically. Yeah, and they
19:09
Speaker 1: were first described by Arctic explorers in seventeen forty one.
19:14
Speaker 1: By seventeen sixty eight they were extinct. So it can't
19:17
Speaker 1: happen on a pretty rapid scale, Yeah, especially when you
19:24
Speaker 1: introduce humans.
19:25
Speaker 2: Yeah, and it you know, it has a domino effect too,
19:27
Speaker 2: because we talked about and everyone knows about the dangers
19:30
Speaker 2: of losing bees. It's not just like, oh, well they're
19:32
Speaker 2: no more bees. That's going to affect pollination and plants,
19:35
Speaker 2: and those plants are being fed on by other animals
19:39
Speaker 2: and it.
19:40
Speaker 1: Tends to have a snowball effect.
19:43
Speaker 2: Like for example, at the end of the last Ice age, mammals,
19:46
Speaker 2: small mammals started to go extinct and because of that,
19:49
Speaker 2: large animals started to go extinct because they like to
19:51
Speaker 2: eat the small animals exactly.
19:53
Speaker 1: Which is the answer to the question why is biodiversity important? Well,
19:57
Speaker 1: because ecosystems thrive and survive on a wide number of
20:01
Speaker 1: species that exist pretty much naturally in balance. Yeah. You know,
20:06
Speaker 1: a pretty good example of that stuff falling out of
20:10
Speaker 1: balance is the passenger pigeon. Are you familiar.
20:15
Speaker 2: Yeah, they're trying to de extinct that thing.
20:19
Speaker 1: Yeah, you want to talk about de extinction.
20:21
Speaker 2: Yeah, Well, the extinction is exactly what it sounds like.
20:24
Speaker 2: It is sort of Jurassic parky it is. In two
20:27
Speaker 2: thousand and three, some scientists revived the Bercardo Bucardo and
20:32
Speaker 2: that's a Spanish mountain goat, and they did it just
20:36
Speaker 2: sort of like Jurassic Park from DNA that was frozen
20:39
Speaker 2: in time. Unfortunately, although it did work initially, the DNA
20:45
Speaker 2: only survived a matter of minutes, but they did it
20:49
Speaker 2: did count as a de extinction.
20:51
Speaker 1: I think there was a live birth that survived a
20:54
Speaker 1: few minutes, wasn't it.
20:56
Speaker 2: Yeah, the animal itself only survived a few minutes.
20:58
Speaker 1: Though, right, It was like, I should not be.
21:03
Speaker 2: That's true, And I mean they basically said, it's happening now,
21:08
Speaker 2: and we have the capabilities, and we may not be
21:12
Speaker 2: able to bring the wooly mammoth back, but we might
21:14
Speaker 2: be able to bring back something.
21:15
Speaker 1: Kind of close, right. So, and that raises in this
21:18
Speaker 1: article that you sent, just this moral question, like should
21:22
Speaker 1: we be doing this just because we can? Does that
21:25
Speaker 1: mean we should? And so like, if you bring back
21:27
Speaker 1: an animal that has been extinct for so long that
21:30
Speaker 1: its habitat is now gone, you know where they gonna live,
21:33
Speaker 1: exactly where you're gonna put it a zoo, that doesn't
21:35
Speaker 1: seem like a good reason to bring an animal back.
21:37
Speaker 1: So we could put it in a zoo.
21:39
Speaker 2: Yeah, And just like maybe this is my opinion here,
21:44
Speaker 2: which we don't do a lot of, but it seems
21:45
Speaker 2: like concentrating on the problems we face now with the
21:48
Speaker 2: extinction rates is something that we should concentrate on, not
21:52
Speaker 2: bringing back the wily mammoth.
21:53
Speaker 1: Right, And that also kind of details of the point
21:56
Speaker 1: that if we have this ability and routinely exercise it.
22:02
Speaker 1: We may be less inclined to protect the stuff we
22:05
Speaker 1: have now for like, oh it's important enough, we'll just
22:08
Speaker 1: genetically re engineer it and bring it back later. Yeah.
22:10
Speaker 2: I think they in the CNN article they like in
22:13
Speaker 2: it to just thinking we have an undue.
22:14
Speaker 1: Button right on the world controls Z. Yeah, no, good, No,
22:19
Speaker 1: it's funny because the author doesn't realize that control Z
22:22
Speaker 1: works outside of Microsoft Word too. I don't know he
22:26
Speaker 1: specifically mentioned control Z and Microsoft word, oh word, specifically
22:32
Speaker 1: Microsoft word. He said, Yeah, that's a little weird. He
22:35
Speaker 1: could be a shill and he was just working it
22:37
Speaker 1: in maybe you know, well.
22:40
Speaker 2: On max though it's not control Maybe he just meant
22:43
Speaker 2: Microsoft and awkwardly put in word maybe, or maybe.
22:46
Speaker 1: That's the only program he knows. Maybe you know, how
22:50
Speaker 1: do I work this? So you were saying that they're
22:54
Speaker 1: trying to bring back the passenger pigeon, right, Yeah, so
22:58
Speaker 1: the passenger pigeon? Is this really neat example of what
23:01
Speaker 1: happens when you have a lack of biodiversity. There were
23:08
Speaker 1: when European settlers came to the New World. Apparently, like
23:13
Speaker 1: one out of every four birds in North America was
23:18
Speaker 1: a passenger pigeon. A quarter of the entire bird population
23:22
Speaker 1: was passenger pigeons. It's a lot of pigeons. There's a
23:24
Speaker 1: ton of pigeons. There are so many that you could
23:27
Speaker 1: just like shoot into like a flock, and you would
23:29
Speaker 1: kill a couple hundred. Literally, it was there were that many.
23:33
Speaker 1: The thing is is, if you read fourteen ninety three
23:37
Speaker 1: or fourteen ninety one, I can't remember which one it is,
23:39
Speaker 1: but both are excellent books by Charles C. Mann. He
23:41
Speaker 1: talks about the passenger pigeon and how they've recently realized
23:45
Speaker 1: that there were so many passenger pigeons because a century before,
23:51
Speaker 1: one of their great predators, the native American, had been
23:55
Speaker 1: wiped out by disease that had been introduced to the
23:57
Speaker 1: continent about a century before that. So by the time
24:01
Speaker 1: the Europeans got here and really started to settle an
24:03
Speaker 1: encounter the passenger pigeon, they're like, God, look at all
24:07
Speaker 1: these pigeons, and didn't realize that the pigeon population had
24:10
Speaker 1: exploded because their natural predator had died off right, and
24:14
Speaker 1: so we in turn hunted them into extinction. So because
24:18
Speaker 1: of one near extinction, another species was allowed to thrive
24:23
Speaker 1: and explode, and then that when they were faced with
24:28
Speaker 1: their their predator again, humans, they were eventually wiped out
24:32
Speaker 1: and went extinct.
24:33
Speaker 2: Yeah, the American Buffalo. We almost sunned them out of existence.
24:36
Speaker 1: Yeah, were it not for Ted Turner.
24:37
Speaker 2: Yeah, we tried our best too. They were just shooting
24:40
Speaker 2: those things for fun.
24:41
Speaker 1: Yeah at one point, man, that's disgusting. It is disgusting.
24:43
Speaker 2: You hear about the trains, Yeah, just going through the
24:46
Speaker 2: West and just shooting out the windows at the Buffalo
24:48
Speaker 2: for no reason.
24:49
Speaker 1: Yeah, and doing nothing, just leaving them there to rot. Unbelievable.
24:52
Speaker 1: Remember we did an episode on the Buffalo that was
24:55
Speaker 1: a good one.
24:55
Speaker 2: So sad, No, it was good. Well it was sad, dude.
25:00
Speaker 1: Okay.
25:00
Speaker 2: So if you want to talk about extinction level events,
25:05
Speaker 2: that's a whole different deal.
25:06
Speaker 1: You want to talk buster rhymes.
25:08
Speaker 2: That's not a slow gradual extinction. That is some big
25:14
Speaker 2: thing that happens that wipes out a lot of living
25:17
Speaker 2: things all at once. And they estimate there's been more
25:20
Speaker 2: than twenty of these in the history of the world, but.
25:25
Speaker 1: Five of them.
25:25
Speaker 2: They call them the Big Five, right for a reason,
25:28
Speaker 2: for good reason. And we'll just go through those kind
25:30
Speaker 2: of quickly. Now, the Ordo Vissian extinction. It's about four
25:35
Speaker 2: hundred and ninety million years ago, and that wiped out
25:39
Speaker 2: about half of all animal families.
25:41
Speaker 1: And the reason it wiped out about half was because
25:44
Speaker 1: at the time, most of the stuff on Earth still
25:46
Speaker 1: lived in the sea. Glaciers formed at this time, lowering
25:50
Speaker 1: sea levels, which meant that animals that lived in a
25:52
Speaker 1: certain depth of the sea, usually toward the surface, lost
25:56
Speaker 1: their habitat boiled yeah maybe yeah, or were brought down
26:01
Speaker 1: to the level where their predators like to hang out
26:03
Speaker 1: and we're eaten on mass. But that accounted for that extinction,
26:07
Speaker 1: which is kind of rare because, as you'll see when
26:10
Speaker 1: we're talking about the Big Five or mass extinctions in general,
26:13
Speaker 1: it's very difficult to pinpoint exactly what happened. So that's
26:16
Speaker 1: one of the rare ones that were like, pretty sure,
26:18
Speaker 1: this is why all these all this life went extinct
26:21
Speaker 1: all of a sudden. Yeah.
26:22
Speaker 2: And one reason it's difficult it is because it was
26:24
Speaker 2: almost five hundred million years ago.
26:25
Speaker 1: That's another reason it's kind of tough.
26:27
Speaker 2: Here in twenty fourteen, number two, I feel like Letterman
26:32
Speaker 2: number two on the top five extinction, the Late Devonian extinction.
26:37
Speaker 2: They're still debating about that, and about a quarter of
26:40
Speaker 2: the marine families. And by the way, we should mention
26:43
Speaker 2: when they research these things, they home in on family
26:46
Speaker 2: and genera in the big classification group.
26:51
Speaker 1: Right.
26:52
Speaker 2: They don't say, like, oh, look at these kingdoms that
26:54
Speaker 2: have disappeared or these phylum. They go down to the
26:57
Speaker 2: smaller levels.
26:58
Speaker 1: Right, and family and jena are just above species as
27:01
Speaker 1: far as the taxonomy is concerned, exactly.
27:05
Speaker 2: So what I say about half of the marine genera
27:09
Speaker 2: and that was three hundred and sixty million years.
27:11
Speaker 1: Ago, right, No idea what caused that one? No idea?
27:14
Speaker 1: At least you and I have no idea.
27:16
Speaker 2: Yeah, I don't think they care about that one too much.
27:19
Speaker 1: The Permian Triassic extinction, this is a This is a
27:23
Speaker 1: pretty big one. This is the biggest one ever. This
27:25
Speaker 1: is the one they call the great Dying, right, I
27:28
Speaker 1: think so. I've seen estimates of as much as ninety
27:31
Speaker 1: five to ninety six percent of all life that's crazy
27:35
Speaker 1: died off during this this extinction event. In this article,
27:40
Speaker 1: it says eighty five percent of marine genera and seventy
27:43
Speaker 1: percent of land species when extinct, And that was two
27:46
Speaker 1: hundred and fifty million years ago. There's a lot of
27:49
Speaker 1: people who have different ideas about what did it, but
27:53
Speaker 1: they think it's possible as volcanic activity creating acid rain. Yeah,
27:57
Speaker 1: that's a big one that possibly happened more than once.
28:00
Speaker 2: Was that the one where I don't know, I think
28:02
Speaker 2: that was the the KPg event was the one where
28:05
Speaker 2: they think they're not exactly how it happened, but they
28:08
Speaker 2: might have been.
28:09
Speaker 1: Just broiled and then awesome broiled on the face of
28:12
Speaker 1: the Earth. Yeah, which would have happened pretty quickly too, actually.
28:15
Speaker 2: And I think that one is if because they think
28:18
Speaker 2: it may have burst through the atmosphere, right, Yeah, so
28:21
Speaker 2: just rained hot debris everywhere.
28:22
Speaker 1: That's the one that got rid of the dinosaurs. Yeah,
28:24
Speaker 1: sixty five million years ago. What is it called the
28:27
Speaker 1: k hyphen PG.
28:29
Speaker 2: Yeah, the Cretaceous Paleogene event now.
28:31
Speaker 1: And that's the one where they are pretty sure that
28:34
Speaker 1: an asteroid hit Central America, Yeah, and sent all of
28:40
Speaker 1: this rock yeah, like basically vaporized rock with away from
28:45
Speaker 1: Earth with so much force that this stuff made it
28:48
Speaker 1: out of the atmosphere yeah, and then started to come
28:50
Speaker 1: back down and as it did, it generated thermal heat
28:54
Speaker 1: enough to bring the broil down on Earth.
28:58
Speaker 2: Yeah, and that's the one of two sub explanations. The
29:01
Speaker 2: other is that the old familiar ash basically kept photosynthesis
29:08
Speaker 2: from it, like it blacked out the sun.
29:09
Speaker 1: Yeah, like a nuclear winner. Yeah, yeah, pretty nuts. But
29:13
Speaker 1: we skipped number four. Yeah, for no good reason.
29:16
Speaker 2: The end Triassic extinction killed about twenty percent of marine families,
29:21
Speaker 2: about half of marine genera, and that was two hundred
29:24
Speaker 2: million years ago.
29:25
Speaker 1: Yeah. And again, like with a mass extinction, there's there's
29:29
Speaker 1: no real definition for it. I found I was looking
29:33
Speaker 1: to see, Okay, who's the body that says, like, okay,
29:36
Speaker 1: a mass extinction event took place. It's again, the fossil
29:41
Speaker 1: record is incomplete enough, and we're making guesses in mathematical guesses,
29:45
Speaker 1: but still guesses to the extent that we don't have
29:48
Speaker 1: a real definition for what constitutes a mass extinction. But
29:53
Speaker 1: those five were so massive, yeah, that there's virtually no
29:58
Speaker 1: debate whatsoever that those account for mass extinction events. Yeah,
30:05
Speaker 1: it's kind of like you know it when you see
30:07
Speaker 1: it kind of thing. But there's no agreement on how
30:10
Speaker 1: paragraphy pretty much, Yeah, there's no agreement on how fast
30:14
Speaker 1: it happened. It has to happen, or how widespread it
30:17
Speaker 1: has to happen. But typically it's like a large percentage
30:21
Speaker 1: of all of the animals alive. Yeah, something like twenty percent, say,
30:25
Speaker 1: of all living animal species, not just animals. Animal species
30:29
Speaker 1: just die off. Yeah, and it's worldwide. That's another that
30:33
Speaker 1: seems to be another factor in defining a massive stec.
30:37
Speaker 1: How widespread. Yeah, sure, so these events were pretty big. Yeah.
30:42
Speaker 2: And one of the I think one of the researchers
30:44
Speaker 2: in the article you sent made a pretty good point
30:46
Speaker 2: that the current mass extinct extinction that we're in now,
30:50
Speaker 2: which we're going to talk about in depth here in
30:52
Speaker 2: a minute, he said, these are way more dangerous because
30:56
Speaker 2: in the event of an asteroid, let's say, while it
30:59
Speaker 2: might really it's one bad event, and right afterward, the
31:04
Speaker 2: world starts to try and recoup. It may take a
31:07
Speaker 2: million years, but it tries its best to start reforming
31:10
Speaker 2: life and get going again. Where in now there's no
31:12
Speaker 2: stress relief, it's just a constant. There's no recuperation because
31:17
Speaker 2: it's not over.
31:18
Speaker 1: Right, or the recuperation will come, but we won't be
31:21
Speaker 1: around to see it, because the breaking point will be
31:25
Speaker 1: us wiping ourselves out. By wiping out the biodiversity, and
31:29
Speaker 1: there is a kind of this whole moralistic thing to
31:32
Speaker 1: the idea of extinction. There's this whole human guilt. But
31:36
Speaker 1: if you just kind of take a step back and
31:38
Speaker 1: look at mass extinction intellectually, it doesn't wipe out life.
31:45
Speaker 1: It just changes everything. Right, So for one species it
31:51
Speaker 1: might be a boom time. For everybody else it's a
31:55
Speaker 1: dying off time. But it's all in your perspective.
31:58
Speaker 2: Well, yeah, this beautiful Earth that we know and love
32:01
Speaker 2: now isn't anything like it was one hundred million years.
32:04
Speaker 1: Ago exactly, And there's not necessarily a set level that
32:08
Speaker 1: or a baseline that Earth is supposed to be at.
32:11
Speaker 2: Right, because nature doesn't care, right, and nature's not like,
32:15
Speaker 2: oh well, we got all these people here now and
32:18
Speaker 2: things seem pretty modern and they got smartphones, so maybe
32:21
Speaker 2: we should just protect this version.
32:24
Speaker 1: They're like, what, what's the cycle? Every what? Ten million
32:26
Speaker 1: years for a species? For species? Okay, it's a life
32:29
Speaker 1: span of a species on average.
32:31
Speaker 2: So basically every what ten thousand, ten million years? The
32:36
Speaker 2: Earth it just doesn't care.
32:38
Speaker 1: No, The point is is, for a species, it's lifespan
32:41
Speaker 1: is ten million years, and the Earth is not caring
32:43
Speaker 1: every day of that. Yeah, it doesn't care.
32:46
Speaker 2: It's just stumbling toward the next event, basically exactly that
32:50
Speaker 2: will one day probably happen.
32:52
Speaker 1: The thing is is all of this is not to
32:54
Speaker 1: say that humans are off the hook. All evidence that's
32:57
Speaker 1: coming in now is showing that we are doing a
33:00
Speaker 1: lot to speed up extinction events and create a mass extinction,
33:05
Speaker 1: so much so that the Big Five is possibly the
33:08
Speaker 1: Big six, and we may be in the very beginning
33:10
Speaker 1: stages of the sixth one. And we'll talk about that
33:14
Speaker 1: right after this. So, Chuckers, we've been talking about mass
33:29
Speaker 1: extinction events. There's a Big five, and a lot of
33:33
Speaker 1: people are saying, now there's six, and the six to
33:35
Speaker 1: one is human caused, so much so that geologists are
33:39
Speaker 1: proposing that we call our current epoch the anthropos scene,
33:45
Speaker 1: because humans are having such an impact on Earth that
33:48
Speaker 1: they imagine ten thousand years from now, geologists will be
33:52
Speaker 1: able to look and point to this layer and say,
33:54
Speaker 1: here's where humans started. Yeah, let's get in the way
33:58
Speaker 1: back machine. Oh yeah, let's crank this pace up. Does
34:00
Speaker 1: it have enough charisine?
34:01
Speaker 2: Oh, it's got enough kerosene, buddy, Because we're going back
34:04
Speaker 2: about fifty thousand years Well.
34:06
Speaker 1: You got okay, and we're bringing spiritual.
34:08
Speaker 2: And we're going to go to Australia even because it's
34:11
Speaker 2: just nice down there. And what I see around me
34:14
Speaker 2: are these huge wombat like things that are.
34:17
Speaker 1: As big as hippos. Huge.
34:18
Speaker 2: And I see a tortoise over there that's the size
34:21
Speaker 2: of a VW beetle, and this weird short faced kangaroo
34:27
Speaker 2: and it's ten feet tall.
34:28
Speaker 1: Ten foot tall kangaro. Look at the size of that thing.
34:30
Speaker 2: And everything is crazy. But let's just unpack here and
34:34
Speaker 2: let's start propagating you and me.
34:37
Speaker 1: Okay, I'm going to make a boy beer just for safety,
34:40
Speaker 1: all right, it sounds like I need to defend you
34:41
Speaker 1: off too.
34:42
Speaker 2: And you know what, it's weird. Things are starting to
34:46
Speaker 2: disappear around us as we grow and as we expand,
34:50
Speaker 2: and and scene.
34:53
Speaker 1: That was nice. Can we get out of here because
34:55
Speaker 1: that ten foot tall kangaroo's eyeing us, Well not anymore,
35:04
Speaker 1: but he's dead.
35:05
Speaker 2: Oh, because they'd believe a lot of people think that
35:09
Speaker 2: around fifty thousand years ago, when human started expanding their footprint,
35:15
Speaker 2: that it was a very inconvenient correlation with species dying
35:20
Speaker 2: out as we've spread about the Earth.
35:22
Speaker 1: Yeah, this sixth mass extinction. I apologize for not being
35:28
Speaker 1: able to say sixth correctly. That's right, But there's a
35:33
Speaker 1: huge debate and it's still it's not settled. Both sides
35:36
Speaker 1: are like, we're right, right, another one is like, we're right.
35:40
Speaker 1: The thing is both sides agree like, yeah, we're in
35:42
Speaker 1: the midst of a sixth extinction, and isn't that what matters?
35:46
Speaker 1: But is it human caused or is the result of
35:48
Speaker 1: climate change? And just because it's the result of climate
35:52
Speaker 1: change doesn't mean that if you take the trail back
35:54
Speaker 1: far enough, it isn't necessarily human cause. Yeah, but these
35:58
Speaker 1: are the two debates. So one is the theory of overkill,
36:01
Speaker 1: which is the one you were just describing.
36:03
Speaker 2: Yeah, and that was describing Australia fifty thousand years ago.
36:07
Speaker 2: If we want to get back in the way back
36:09
Speaker 2: machine and go to North America eleven thousand years ago,
36:12
Speaker 2: three quarters of our largest animals started to die out,
36:17
Speaker 2: like the mastodon and the wooly mammoth and the giant beaver,
36:20
Speaker 2: sabertooth tiger, and not coincidentally, probably that's right around the
36:24
Speaker 2: time where we first walked over the bearing land Bridge
36:27
Speaker 2: and set up shop here in North America.
36:29
Speaker 1: Yeah. The thing is is you can also say, well
36:31
Speaker 1: that kind of gives or takes a few thousand years,
36:34
Speaker 1: and yeah, you can. That's definitely stretchable, but it's just
36:37
Speaker 1: not been proven. So there is a huge correlation between
36:41
Speaker 1: the spread of humans and the death of what are
36:43
Speaker 1: called MegaFon a huge land animals. Yeah, and they say
36:47
Speaker 1: that that theory of overkill says that we came along
36:50
Speaker 1: with our smart little toolkits, which included like spearheads and
36:54
Speaker 1: arrows and axes and clubs and domesticated dogs after a
36:58
Speaker 1: certain point in time, sure, and over hunted either these
37:02
Speaker 1: huge like hippo sized marsupials, yeah, or we hunted things
37:09
Speaker 1: that were slightly smaller that the huge hippo sized marsupials. Eight.
37:14
Speaker 1: Either way, we contributed directly to their mass extinction. Yeah.
37:19
Speaker 2: And they think generally that overhunting isn't the very least,
37:23
Speaker 2: it's not the sole cause, because you probably just can't
37:26
Speaker 2: hunt enough. The amount of people that we had, especially
37:29
Speaker 2: in a place like Australia which wasn't super heavily founded.
37:34
Speaker 2: You know, it wasn't like ten million people moved to
37:36
Speaker 2: Australia overnight, you know, right, So they say overhunting is
37:40
Speaker 2: probably not the sole cause, but maybe a factor. But
37:43
Speaker 2: other things humans did, like maybe in Australia they started
37:47
Speaker 2: burning shrubs to clear land, and maybe those shrubs were
37:51
Speaker 2: eaten by a certain species, right, and then that caused
37:53
Speaker 2: that domino effect.
37:54
Speaker 1: Again. Another the other camp that basically says, no, it's
37:57
Speaker 1: climate change and it's fairly natural. Other people might say
38:02
Speaker 1: it's human caused climate change. But for the most part,
38:05
Speaker 1: if you are a climate change extinction proponent, you're probably
38:10
Speaker 1: just believe that this is a natural process that the
38:13
Speaker 1: Earth is undergoing and humans didn't have enough of an
38:16
Speaker 1: impact early on to account for the loss of a
38:19
Speaker 1: lot of these species. Yeah. This one study pointed to
38:23
Speaker 1: a place called Sahul, which was Australia, New Guinea and
38:27
Speaker 1: Tasmania all joined together in this mega continent. That was
38:31
Speaker 1: a crazy place. There was several tens of thousands of
38:34
Speaker 1: years ago, and they were saying that by the time
38:36
Speaker 1: humans arrived in Sahul or Australia, most of the megaphone
38:41
Speaker 1: was already gone. It was gone as a result of
38:43
Speaker 1: climate change, and there's no evidence that we had a
38:46
Speaker 1: toolkit capable of killing these animals, you know at this time. Yeah. True,
38:52
Speaker 1: So the debate still rages on.
38:54
Speaker 2: Yeah, and you know, there's been several ice ages that
38:57
Speaker 2: didn't make things go extinct, right, People point to that
39:01
Speaker 2: as maybe another counter argument. But the researchers you sent
39:04
Speaker 2: along did this pretty cool thing. They did the first
39:07
Speaker 2: global analysis of mapping large animals during this period one
39:14
Speaker 2: hundred and thirty two thousand to one thousand years ago,
39:17
Speaker 2: and it was the first time they were able to
39:18
Speaker 2: really get a fine point on this geographical variation and
39:22
Speaker 2: species loss. And they did find that one hundred and
39:25
Speaker 2: seventy seven species of large mammals disappeared during that period
39:29
Speaker 2: where we were starting to spread out as a species.
39:34
Speaker 1: Which apparently is, as it's put in this article, a
39:38
Speaker 1: massive loss. Yeah.
39:40
Speaker 2: And they said, you know, they expect these kind of
39:42
Speaker 2: things to happen on an island, like if you go
39:44
Speaker 2: to Hawaii or you know, any island. They say that
39:47
Speaker 2: survival is the exception when humans invade an island exactly,
39:51
Speaker 2: but to happen on like a continent, it's pretty it's
39:54
Speaker 2: pretty amazing to think about the human.
39:56
Speaker 1: Impact still an island. Well, yeah, I guess that's a
39:59
Speaker 1: good point. But the jury is still out though, and
40:03
Speaker 1: exactly what's causing this. Most scientists agree that we are
40:08
Speaker 1: in an mass extinction event, and it's happening pretty quickly.
40:15
Speaker 1: Something like I think a third of all coral reefs
40:18
Speaker 1: are in danger of extinction, a third of amphibians, I believe.
40:24
Speaker 2: Yeah, and a quarter of all mammals and an eighth
40:25
Speaker 2: of all birds are all classified as threatened with extinction.
40:29
Speaker 1: And this is happening around the world, So it's fitting
40:32
Speaker 1: the criteria for a mass extinction.
40:34
Speaker 2: Yeah, they're basically chalking up to the pace of human expansion.
40:38
Speaker 2: And you know, if you consider that farming and logging
40:42
Speaker 2: and building roads and buildings, and most of the world's
40:46
Speaker 2: waterways have been diverted or damned at this point or
40:48
Speaker 2: manipulated somehow. Only two percent of rivers in the United
40:53
Speaker 2: States run unimpeded. Two percent everything else has been altered
40:56
Speaker 2: in some way. Chemical plants affecting CO two in the atmosphere,
41:03
Speaker 2: it's having an effect.
41:04
Speaker 1: And that CO two actually in the atmosphere is having
41:07
Speaker 1: another effect called ocean acidification, which has been described as
41:12
Speaker 1: global warming's evil twin. As more and more CO two
41:16
Speaker 1: gets released in the atmosphere. The oceans scramble to keep
41:21
Speaker 1: up by absorbing more and more, and it stores some
41:24
Speaker 1: of that by turning some of it into acid, which
41:27
Speaker 1: lowers the pH of the ocean, which is making the
41:30
Speaker 1: ocean unfit for a lot of life. But as to
41:35
Speaker 1: kind of demonstrate how mass extinctions is bad for one
41:39
Speaker 1: species great for another, jellyfish populations are booming really so
41:45
Speaker 1: probably because they like the lower pH. Yeah, they like
41:48
Speaker 1: it more acidic, and they're like seriously starting to cause
41:50
Speaker 1: some real problems. And we're just seeing the beginning of this.
41:53
Speaker 1: So it's entirely possible that the next thousand years will
41:57
Speaker 1: see the rise of the jellyfishes the rest of the
41:59
Speaker 1: life on Earth starts to die off.
42:01
Speaker 2: Well, here's a staggering stat the drop in ocean pH
42:05
Speaker 2: levels that have occurred in the past fifty years. They
42:08
Speaker 2: think might exceed what has happened in the past previous
42:11
Speaker 2: fifty million years.
42:12
Speaker 1: Wow, So in the past fifty years.
42:14
Speaker 2: They've changed the basically changed the chemical makeup of the
42:17
Speaker 2: ocean more than the past fifty million.
42:19
Speaker 1: And speaking of fifty years, apparently in the next fifty
42:23
Speaker 1: years and estimated half half of all species on Earth
42:30
Speaker 1: could be extinct.
42:33
Speaker 2: Sucks, man, I want to see a sloth as big
42:34
Speaker 2: as an elephant.
42:35
Speaker 1: Hey, get into de extinction. Well here you just saw
42:40
Speaker 1: and we were in sahul Well yeah it was nice.
42:44
Speaker 2: But I want to, like, I want it to come
42:47
Speaker 2: in the way back machine and bring it to Atlanta.
42:49
Speaker 1: No, I don't think that's a good idea, man. That
42:52
Speaker 1: thing looked like it would go berserk.
42:54
Speaker 2: And finally, unless you have anything else.
42:57
Speaker 1: I don't think so. I'm looking at everything.
42:59
Speaker 2: We have a few highlights of extinct animals that have
43:03
Speaker 2: been rediscovered, which is not the same thing as.
43:05
Speaker 1: Being re engineered. What was this an io nine?
43:08
Speaker 2: Iine, And some of those are pretty good. The Bermuda
43:12
Speaker 2: petrel and disappeared. They fought in the sixteen hundreds, but
43:16
Speaker 2: rediscovered nineteen fifty one. There's about one hundred and eighty
43:19
Speaker 2: of those alive today. Let me see here what else
43:23
Speaker 2: is good? Well, we also we already talked about the
43:24
Speaker 2: Cela camp. The Cuban solan don Solenodon excuse me, discovered
43:30
Speaker 2: in eighteen sixty one, has only been caught thirty seven
43:35
Speaker 2: times in the history of the world. In nineteen seventy
43:39
Speaker 2: they thought it was extinct. It's like a weird rat
43:41
Speaker 2: like species. But then they found one in the seventies,
43:44
Speaker 2: and then another one in two thousand and three. Huh,
43:47
Speaker 2: So like welcome back Cuban Solenodon.
43:49
Speaker 1: So it was like caught during the seventies and then
43:52
Speaker 1: during the period of the seventies revival in the early
43:55
Speaker 1: two thousands.
43:56
Speaker 2: That's right, nice Gilbert's poach turu man.
44:00
Speaker 1: These have weird names. That's why they went extinct because
44:03
Speaker 1: you couldn't say, ye, sloth, you know that we should
44:06
Speaker 1: save the the what Gilbert, Yeah.
44:11
Speaker 2: In eighteen forty one, this is a rabbit size marsupial
44:14
Speaker 2: in Australia and it last appeared in eighteen seventy nine,
44:18
Speaker 2: and they thought, well, this thing's gone up until nineteen
44:20
Speaker 2: ninety four. Came back out and poked his head around
44:24
Speaker 2: and got caught in a few traps. But currently less
44:26
Speaker 2: than one hundred of those in the world. So those
44:29
Speaker 2: are just a few of the ten, and there's more
44:30
Speaker 2: than ten, obviously, But it's always a good story.
44:34
Speaker 1: Sure, it is heartwarming. We think this thing's dead. It's like, yeah,
44:38
Speaker 1: welcome back to the mass extinction exactly. So going on.
44:43
Speaker 1: If you want to know more about extinction, you should
44:45
Speaker 1: read each and every one of the articles we cited.
44:48
Speaker 1: And you can also read this article on HowStuffWorks dot
44:51
Speaker 1: com by typing extinction into the handy search bar. And
44:54
Speaker 1: since I said that it's time for a listener mail,
44:58
Speaker 1: I'm going to call this police interrogation follow up.
45:01
Speaker 2: Okay from Matt Pope a in Victoria, British Columbia. All right,
45:06
Speaker 2: thank you to Vancouver, by the way, for two great shows.
45:09
Speaker 2: Yeah after our great shows in Toronto.
45:12
Speaker 1: Yepkay in Toronto and Vancouver. Very supportive people.
45:16
Speaker 2: And boy that second crowd Vancouver was drunk and rowdy. Hey, guys,
45:21
Speaker 2: just listen to police interrogation. I thought i'd share a
45:24
Speaker 2: couple of quick personal stories that illustrate the pitfalls of
45:27
Speaker 2: relying on nonverbal cues to see if someone's guilty. I've
45:30
Speaker 2: never been in trouble with a law myself, but several
45:32
Speaker 2: years ago I witnessed a crime, called nine to one
45:34
Speaker 2: one to report it. The cop snabbed the perpetrator and
45:36
Speaker 2: a few days later asked me to come down to
45:39
Speaker 2: provide a witness statement. When I arrived, an officer led
45:42
Speaker 2: me into a tiny room that was every bit as
45:43
Speaker 2: bleak as the ones you see on TV. It was
45:45
Speaker 2: a weird experience, even though I wasn't accused of a
45:47
Speaker 2: crime and the cop was polite and is questioning. The
45:50
Speaker 2: interrogation room setting and the power differential between the uniform
45:53
Speaker 2: cop with a gun and my unarmed self made me
45:56
Speaker 2: feel really nervous. I started sweating, my voice shook, and
45:59
Speaker 2: if you been watching my body language through the one
46:01
Speaker 2: way mirror, you would have thought I was guilty.
46:03
Speaker 1: Wow, and he was just a witness. Yeah. The second
46:06
Speaker 1: story is very similar.
46:07
Speaker 2: Every year, our local courthouse as a public event where
46:09
Speaker 2: they give tours and put on a mock trial and
46:11
Speaker 2: actually hang someone.
46:14
Speaker 1: Kidding. I made up that part. That was pretty good.
46:17
Speaker 1: It's supposed to be educational and fun.
46:18
Speaker 2: My father is a lawyer and one year asked me
46:20
Speaker 2: I'd like to play the defendant in the trial. I'm
46:23
Speaker 2: no actor, but I said sure. My character was accused
46:26
Speaker 2: of a minor drug offense, and I went through the
46:28
Speaker 2: whole ordeal, being on trial and testifying my own defense.
46:31
Speaker 2: I'll spare you the details, but afterward my mom said, wow,
46:34
Speaker 2: you looked really guilty up there.
46:36
Speaker 1: I hope you never.
46:37
Speaker 2: Actually are on trial for anything, because they'll lock you
46:39
Speaker 2: up and throw away the key. I learned from these
46:42
Speaker 2: situations the very act of treating someone like a criminal
46:44
Speaker 2: and make him appear guilty. Yeah, reminds me of the
46:47
Speaker 2: Stanford prison study that we've talked about.
46:50
Speaker 1: And there's a Psychology's Nuts about that Psychology's Nuts video
46:54
Speaker 1: on our YouTube channel about the Stanford prison experiment. Yeah,
46:57
Speaker 1: that's a good one. You should check that out.
46:59
Speaker 2: I hope you guys never have to find out the
47:01
Speaker 2: hard way you'll react to police interrogation.
47:04
Speaker 1: If you do, I hope you find a good lawyer.
47:06
Speaker 2: That's from Matt Pope once again in Victoria, BC.
47:08
Speaker 1: H Well, thanks a lot, Matt. That's kooky about your
47:13
Speaker 1: town doing mock trials and stuff like that. Yeah, like
47:15
Speaker 1: hanging a guy, Yeah crazy, he said, it's fun. The
47:20
Speaker 1: only thing that's okay about is they make the guy
47:22
Speaker 1: look like Hitler, right, So it's like hanging Hitler every year,
47:25
Speaker 1: which everybody can get behind. Yeah, they call it the
47:27
Speaker 1: Hitler hang. If you want to send us an email
47:32
Speaker 1: that Chuck feels the need to make up stuff about
47:35
Speaker 1: you can send us an email to Stuff Podcast at
47:38
Speaker 1: iHeartRadio dot com Stuff you Should Know is a production
47:44
Speaker 1: of iHeartRadio.
47:46
Speaker 2: For more podcasts my heart Radio, visit the iHeartRadio app,
47:49
Speaker 2: Apple Podcasts, or wherever you listen to your favorite shows.