1
00:00:08,560 --> 00:00:11,080
Speaker 1: Hey, Daniel, are your kids as tall as you are yet?

2
00:00:11,200 --> 00:00:13,680
Speaker 2: Oh? Not yet. I've still got an inch on my

3
00:00:13,800 --> 00:00:16,800
Speaker 2: fifteen year old, but he's already past my wife. How

4
00:00:16,800 --> 00:00:18,480
Speaker 2: about you. Are your kids taller than you are?

5
00:00:18,960 --> 00:00:22,040
Speaker 1: Not yet, but my son is taller than my wife. No,

6
00:00:22,360 --> 00:00:23,040
Speaker 1: by a lot.

7
00:00:23,200 --> 00:00:26,159
Speaker 2: It's amazing that you never see them actually grow, and

8
00:00:26,239 --> 00:00:28,520
Speaker 2: yet one day they're going to look down on us.

9
00:00:28,640 --> 00:00:32,159
Speaker 1: You mean physically, not figuratively. That's been happening for years

10
00:00:32,159 --> 00:00:34,320
Speaker 1: for me. But at this rate they'll be there. Should

11
00:00:34,320 --> 00:00:36,880
Speaker 1: be twice our height in about five years, right.

12
00:00:38,120 --> 00:00:40,440
Speaker 2: There definitely be twice as smart as we are. I

13
00:00:40,479 --> 00:00:43,680
Speaker 2: mean I'm already forgetting things faster than they're learning them.

14
00:00:44,280 --> 00:00:46,479
Speaker 1: I think my son is already smarter than me. Does

15
00:00:46,520 --> 00:00:49,199
Speaker 1: that mean you've peaked in terms of your brain and

16
00:00:49,240 --> 00:00:49,640
Speaker 1: your height?

17
00:00:49,800 --> 00:00:51,879
Speaker 2: Yeah? I think it's just downhill from here, and I'm

18
00:00:51,920 --> 00:00:54,560
Speaker 2: really not looking forward to incontinental drift.

19
00:00:54,640 --> 00:00:56,360
Speaker 1: Wait, do you mean continental drift?

20
00:00:56,480 --> 00:00:59,000
Speaker 2: No, I mean the inevitable drift into incontinents.

21
00:00:59,320 --> 00:01:17,480
Speaker 1: That would be earth shaking. Hi Am Hoham cartoonists and

22
00:01:17,520 --> 00:01:20,039
Speaker 1: the author of Oliver's Great Big Universe.

23
00:01:20,280 --> 00:01:23,240
Speaker 2: Hi, I'm Daniel. I'm a particle. Physicist and a professor

24
00:01:23,280 --> 00:01:26,080
Speaker 2: at UC Irvine. And I've eaten astronaut ice cream, but

25
00:01:26,120 --> 00:01:28,080
Speaker 2: I've never worn astronaut underwear.

26
00:01:28,240 --> 00:01:31,000
Speaker 1: Why not haven't we all? Wait? Are you talking about

27
00:01:31,080 --> 00:01:34,839
Speaker 1: used Austronauts underwear or brand new Austronauts underwear?

28
00:01:34,959 --> 00:01:36,840
Speaker 2: No, I'm talking about the kind that lets you drive

29
00:01:36,920 --> 00:01:39,199
Speaker 2: cross country without having to stop for a rest break.

30
00:01:39,280 --> 00:01:43,160
Speaker 1: Oh you mean diapers. Wait, why are you bringing up

31
00:01:43,240 --> 00:01:45,640
Speaker 1: astronaut underwear? Is that the topic of today's podcast?

32
00:01:45,800 --> 00:01:49,840
Speaker 2: No, today, we're not talking about incontinents. We're talking about continents, which,

33
00:01:49,880 --> 00:01:52,000
Speaker 2: weirdly are not the opposite of incontinence.

34
00:01:52,360 --> 00:01:54,920
Speaker 1: Yeah, that's the grammar for you, I guess. But anyways,

35
00:01:54,920 --> 00:01:57,520
Speaker 1: welcome to our podcast Daniel and Jorge Explain the Universe,

36
00:01:57,600 --> 00:01:59,680
Speaker 1: a production of iHeartRadio.

37
00:01:59,200 --> 00:02:01,960
Speaker 2: Where we dig in the crazy motions of everything in

38
00:02:02,000 --> 00:02:06,280
Speaker 2: the universe, things swirling around black holes, stuff flowing inside

39
00:02:06,280 --> 00:02:09,800
Speaker 2: our own planet, and the particles moving between our toes.

40
00:02:09,880 --> 00:02:13,120
Speaker 2: Physics in the end is about understanding the movement of things,

41
00:02:13,160 --> 00:02:15,639
Speaker 2: why they move, how they move, where they are going

42
00:02:15,680 --> 00:02:18,560
Speaker 2: to move to, and we want to understand all of it.

43
00:02:18,840 --> 00:02:21,280
Speaker 1: Yeah, it is a motion filled universe full of things

44
00:02:21,280 --> 00:02:23,400
Speaker 1: that are moving fast and things that are moving slow,

45
00:02:23,480 --> 00:02:26,120
Speaker 1: which are all moving nonethe less, and it's up to

46
00:02:26,240 --> 00:02:29,480
Speaker 1: us to try to catch those patterns and see why

47
00:02:29,520 --> 00:02:31,160
Speaker 1: things are doing the things that they are doing.

48
00:02:31,320 --> 00:02:33,000
Speaker 2: And because we live a certain amount of time and

49
00:02:33,040 --> 00:02:35,480
Speaker 2: our life happens at a certain speed, we tend to

50
00:02:35,520 --> 00:02:38,880
Speaker 2: notice things that happen on our time scales, things that

51
00:02:38,960 --> 00:02:42,160
Speaker 2: happen in seconds or days or maybe even years. But

52
00:02:42,200 --> 00:02:44,120
Speaker 2: there's lots of things in the universe that happen on

53
00:02:44,240 --> 00:02:49,280
Speaker 2: much shorter and much faster time scales. Quantum particles operated

54
00:02:49,320 --> 00:02:52,359
Speaker 2: like ten to the negative twenty three seconds, and galaxy

55
00:02:52,400 --> 00:02:56,160
Speaker 2: spend over hundreds of millions of years. So it's easy

56
00:02:56,200 --> 00:03:00,359
Speaker 2: to overlook these very slow moving but very important processes,

57
00:03:00,560 --> 00:03:02,720
Speaker 2: even though they literally shape our world.

58
00:03:02,919 --> 00:03:05,000
Speaker 1: Yeah. I guess we're used to like a certain rhythm

59
00:03:05,160 --> 00:03:08,480
Speaker 1: of time, right, kind of like our brains maybe have

60
00:03:08,560 --> 00:03:09,840
Speaker 1: a certain clock to them.

61
00:03:09,960 --> 00:03:13,840
Speaker 2: Yeah. Probably. And until recently, most humans lives were very

62
00:03:13,880 --> 00:03:16,560
Speaker 2: similar to the lives of their parents and grandparents and

63
00:03:16,639 --> 00:03:20,840
Speaker 2: great grandparents. Right, Culture and technology moved so slowly that,

64
00:03:20,919 --> 00:03:23,000
Speaker 2: you know, five thousand years ago, you could be pretty

65
00:03:23,040 --> 00:03:25,040
Speaker 2: sure that your kid's life was going to be basically

66
00:03:25,080 --> 00:03:27,720
Speaker 2: the same as yours, and you could imagine that life

67
00:03:27,720 --> 00:03:31,800
Speaker 2: had been like this forever, that fast changes had never occurred,

68
00:03:31,840 --> 00:03:33,880
Speaker 2: that the universe was basically static.

69
00:03:34,080 --> 00:03:36,440
Speaker 1: Yeah, it's amazing how fastings changed. I feel like within

70
00:03:36,560 --> 00:03:39,760
Speaker 1: our lifetime the world has changed several times now. Like

71
00:03:40,080 --> 00:03:41,880
Speaker 1: when I was growing up, we didn't even have email

72
00:03:42,880 --> 00:03:43,480
Speaker 1: or cell phones.

73
00:03:43,600 --> 00:03:46,080
Speaker 2: Is that why you never got used to answering email? Yeah?

74
00:03:46,080 --> 00:03:48,400
Speaker 1: I haven't. I haven't picked up with that yet. See,

75
00:03:48,440 --> 00:03:50,560
Speaker 1: I I worked that fine. Some things you don't have

76
00:03:50,600 --> 00:03:50,960
Speaker 1: to learn.

77
00:03:51,160 --> 00:03:53,200
Speaker 2: We do live in a really fascinating era where we

78
00:03:53,280 --> 00:03:55,720
Speaker 2: know that our kids' lives will be different from our

79
00:03:55,800 --> 00:03:59,040
Speaker 2: lives and fundamental ways that we can't really anticipate. That's

80
00:03:59,080 --> 00:04:01,960
Speaker 2: pretty exciting, but I think it also narrows our view

81
00:04:02,000 --> 00:04:05,080
Speaker 2: and makes us focus on rapid changes in our environment.

82
00:04:05,240 --> 00:04:08,200
Speaker 2: It makes it harder even to see the slow moving,

83
00:04:08,320 --> 00:04:10,960
Speaker 2: big changes that frame everything around us.

84
00:04:11,280 --> 00:04:14,000
Speaker 1: Yeah, we live almost in like this giant clockward of

85
00:04:14,040 --> 00:04:18,560
Speaker 1: a universe, right with galaxy spinning and galaxy clusters churning

86
00:04:18,600 --> 00:04:22,000
Speaker 1: and turning and planets spinning out there. It's kind of

87
00:04:22,240 --> 00:04:24,440
Speaker 1: hard to notice that all of these things are happening,

88
00:04:24,480 --> 00:04:26,560
Speaker 1: But they are happening, and there's a lot happening.

89
00:04:26,720 --> 00:04:28,960
Speaker 2: Yeah, and we tend to think about things out there

90
00:04:29,000 --> 00:04:32,960
Speaker 2: in space happening sort of slowly on unstately time scales.

91
00:04:33,400 --> 00:04:35,520
Speaker 2: But that's just because we're not used to thinking about

92
00:04:35,560 --> 00:04:38,600
Speaker 2: things in terms of millions and millions of years. If

93
00:04:38,640 --> 00:04:40,960
Speaker 2: you looked at a time lapse of the universe over

94
00:04:41,000 --> 00:04:43,880
Speaker 2: billions of years, it would seem very chaotic, very dramatic

95
00:04:43,920 --> 00:04:46,240
Speaker 2: to you. It would be turbulent, it'd be violent, it

96
00:04:46,240 --> 00:04:49,039
Speaker 2: would be really impressive to watch. And the same thing

97
00:04:49,080 --> 00:04:51,279
Speaker 2: happens not just out there in the universe, but also

98
00:04:51,440 --> 00:04:52,239
Speaker 2: under our feet.

99
00:04:52,400 --> 00:04:54,479
Speaker 1: Yeah, I kind of have trouble thinking in terms of

100
00:04:54,520 --> 00:04:57,760
Speaker 1: weeks or months. I'm more of a live by the

101
00:04:57,839 --> 00:05:00,240
Speaker 1: day kind of person, live in the moment. What are

102
00:05:00,240 --> 00:05:01,000
Speaker 1: you talking about again?

103
00:05:02,839 --> 00:05:05,400
Speaker 2: But as we piece together the story of how our

104
00:05:05,440 --> 00:05:07,960
Speaker 2: planet got here, how our solar system formed, how the

105
00:05:08,000 --> 00:05:11,240
Speaker 2: planets did their dance to end up in this configuration,

106
00:05:11,560 --> 00:05:14,200
Speaker 2: we also see signs on Earth that there is a

107
00:05:14,279 --> 00:05:17,240
Speaker 2: larger story to tell, that things have not always looked

108
00:05:17,400 --> 00:05:18,520
Speaker 2: the way that they do now.

109
00:05:18,720 --> 00:05:21,160
Speaker 1: Yeah, our planet is pretty big, at least compared to us,

110
00:05:21,160 --> 00:05:24,239
Speaker 1: and it moves in pretty slow ways, and in earth

111
00:05:24,360 --> 00:05:25,360
Speaker 1: moving ways.

112
00:05:25,160 --> 00:05:27,400
Speaker 2: And by understanding how that works. We can hope to

113
00:05:27,440 --> 00:05:30,640
Speaker 2: gain some understanding for whether it happens on other planets,

114
00:05:30,640 --> 00:05:34,320
Speaker 2: and whether aliens out there also feel their Earth moving

115
00:05:34,440 --> 00:05:35,720
Speaker 2: beneath their feet.

116
00:05:35,920 --> 00:05:37,880
Speaker 1: Yeah, and whether they live in the moment or if

117
00:05:37,880 --> 00:05:39,960
Speaker 1: they think in terms of eons.

118
00:05:39,760 --> 00:05:42,360
Speaker 2: And whether they'll ever answer our email so to be.

119
00:05:42,440 --> 00:05:50,040
Speaker 1: On the podcast, we'll be asking the question what drives

120
00:05:50,120 --> 00:05:52,560
Speaker 1: the movement of Earth's continents?

121
00:05:53,040 --> 00:05:57,080
Speaker 2: It's not geographers or geologists.

122
00:05:56,480 --> 00:05:58,800
Speaker 1: And I guess we're talking about the actual movement of

123
00:05:58,880 --> 00:06:02,000
Speaker 1: earth continents, not like the people redrawing the lines of

124
00:06:02,040 --> 00:06:03,359
Speaker 1: them or renaming them.

125
00:06:03,440 --> 00:06:05,960
Speaker 2: I'm pretty sure the maps follow the continents rather than

126
00:06:05,960 --> 00:06:08,480
Speaker 2: the other way around. I don't think Earth checks our

127
00:06:08,480 --> 00:06:11,320
Speaker 2: maps to decide where Asia is going to slide over to.

128
00:06:11,760 --> 00:06:14,240
Speaker 1: Oh yeah. Is there a clear line between Asia and

129
00:06:14,279 --> 00:06:16,000
Speaker 1: Europe or is it political?

130
00:06:16,080 --> 00:06:18,279
Speaker 2: I think there actually is a division in the techtonic

131
00:06:18,360 --> 00:06:19,200
Speaker 2: plates between them.

132
00:06:19,400 --> 00:06:22,200
Speaker 1: Hmmm. Does that mean that there are countries that are

133
00:06:22,200 --> 00:06:25,520
Speaker 1: in both continents? Clearly this is not a geography podcast.

134
00:06:25,880 --> 00:06:28,919
Speaker 2: There's a massive Eurasian plate that most of Europe and

135
00:06:28,960 --> 00:06:31,880
Speaker 2: most of Asia is on. But like Saudi Arabia, for example,

136
00:06:31,920 --> 00:06:34,600
Speaker 2: which is considered to be part of Asia is on

137
00:06:34,640 --> 00:06:37,200
Speaker 2: its own plate, and India is on its own plate

138
00:06:37,279 --> 00:06:37,800
Speaker 2: as well.

139
00:06:37,920 --> 00:06:40,400
Speaker 1: So you're saying it is sort of like a subjective

140
00:06:40,520 --> 00:06:42,599
Speaker 1: kind of or at least for some continents.

141
00:06:42,720 --> 00:06:45,000
Speaker 2: I think the definition of a continent is a little

142
00:06:45,000 --> 00:06:47,840
Speaker 2: bit subjective. Yeah, but the definition of a continental plate,

143
00:06:48,200 --> 00:06:51,080
Speaker 2: these things are scientific and geological, Like we can see

144
00:06:51,080 --> 00:06:53,960
Speaker 2: where the edges are of these cracks in the crust.

145
00:06:54,240 --> 00:06:56,520
Speaker 1: You mean it's kind of leaky or definition, it's a

146
00:06:56,520 --> 00:06:57,880
Speaker 1: little incontinent.

147
00:06:58,040 --> 00:07:00,320
Speaker 2: A little incontinent, exactly, all right.

148
00:07:00,320 --> 00:07:02,240
Speaker 1: Well, as usual, we're wondering how many people out there

149
00:07:02,240 --> 00:07:04,679
Speaker 1: had thought about the question of what drives the movement

150
00:07:04,800 --> 00:07:08,120
Speaker 1: of earth technic plates and continents, And so this time

151
00:07:08,200 --> 00:07:10,680
Speaker 1: Daniel went out there into the wild of the UC

152
00:07:10,800 --> 00:07:13,040
Speaker 1: Irvine campus to ask people this question.

153
00:07:13,200 --> 00:07:16,440
Speaker 2: That's right, And today's episode is dedicated to TJ, a

154
00:07:16,600 --> 00:07:19,360
Speaker 2: listener out there in recovery from a stroke who requested

155
00:07:19,680 --> 00:07:23,080
Speaker 2: this topic specifically. So thanks very much everybody who answers

156
00:07:23,080 --> 00:07:25,119
Speaker 2: these questions, and thanks to everybody in the USA irun

157
00:07:25,200 --> 00:07:27,600
Speaker 2: campus who put up with a weird physicist with a

158
00:07:27,680 --> 00:07:28,440
Speaker 2: phone in their face.

159
00:07:28,720 --> 00:07:30,120
Speaker 1: So think about it for a second, what do you

160
00:07:30,160 --> 00:07:33,600
Speaker 1: think drives the movement of Earth's continents. Here's what people

161
00:07:33,600 --> 00:07:34,040
Speaker 1: have to say.

162
00:07:34,280 --> 00:07:36,520
Speaker 2: Do you know what makes the continents move, of the

163
00:07:36,680 --> 00:07:38,440
Speaker 2: ocean continents drift?

164
00:07:38,760 --> 00:07:43,640
Speaker 3: Yeah, probably because we have this plates, geological plates that

165
00:07:43,760 --> 00:07:45,200
Speaker 3: are constantly moving.

166
00:07:45,600 --> 00:07:47,720
Speaker 1: But I'm not a geologist, so actually, to be honest,

167
00:07:47,760 --> 00:07:48,280
Speaker 1: I don't know.

168
00:07:48,440 --> 00:07:50,520
Speaker 3: It's not like because like the liquid and the Earth,

169
00:07:50,560 --> 00:07:52,840
Speaker 3: like the Earth center is still liquid and therefore, like

170
00:07:52,880 --> 00:07:55,560
Speaker 3: the plates on top are like moving along because there's

171
00:07:55,600 --> 00:07:57,480
Speaker 3: I'm not sure if there are currens going on and

172
00:07:57,560 --> 00:07:59,280
Speaker 3: that's why we are like plates are moving.

173
00:08:00,240 --> 00:08:02,720
Speaker 2: I'm not sure what it makes the continents move. Do

174
00:08:02,800 --> 00:08:04,760
Speaker 2: I know what causes the continents to drift?

175
00:08:05,400 --> 00:08:07,960
Speaker 3: I mean, they call it continental drift, but I don't

176
00:08:07,960 --> 00:08:08,960
Speaker 3: know what started them moving.

177
00:08:09,400 --> 00:08:13,680
Speaker 1: Uh yeah, So I understand that that is caused because

178
00:08:13,880 --> 00:08:16,280
Speaker 1: the plates are sitting pretty much on malten rock, so

179
00:08:16,640 --> 00:08:20,360
Speaker 1: one one across the other, they're kind of like crumpling,

180
00:08:20,840 --> 00:08:22,280
Speaker 1: So that's what's moving.

181
00:08:22,440 --> 00:08:23,680
Speaker 2: The stuff that's on top right.

182
00:08:23,760 --> 00:08:25,440
Speaker 1: Well, I just I know that the malten rock is

183
00:08:25,480 --> 00:08:27,800
Speaker 1: like revolving right inside the core.

184
00:08:27,840 --> 00:08:29,080
Speaker 2: But that's about what I know.

185
00:08:29,160 --> 00:08:32,679
Speaker 1: I don't understand that tectonic plates.

186
00:08:32,160 --> 00:08:34,120
Speaker 2: For those are the plates, why do they move? The

187
00:08:34,240 --> 00:08:36,800
Speaker 2: Magma movement, anybody else.

188
00:08:37,679 --> 00:08:42,800
Speaker 1: I have no idea. All right, it kind of seems

189
00:08:42,840 --> 00:08:45,440
Speaker 1: like you took a lot of people by surprise. They're like,

190
00:08:45,480 --> 00:08:48,920
Speaker 1: what are you doing? Why are you putting a microphone

191
00:08:48,960 --> 00:08:50,920
Speaker 1: in my face? How do you approach people by the way?

192
00:08:50,920 --> 00:08:52,440
Speaker 1: Do you just walk up to them or do you

193
00:08:52,480 --> 00:08:53,760
Speaker 1: bring out the microphone later?

194
00:08:55,000 --> 00:08:56,800
Speaker 2: You know. The very first time I did it, I

195
00:08:56,920 --> 00:08:58,920
Speaker 2: brought my kids with me so I would seem less

196
00:08:58,960 --> 00:09:01,680
Speaker 2: weird and threatening, because I was expecting most people say no.

197
00:09:02,240 --> 00:09:04,760
Speaker 2: But what I discovered is that most people say yes,

198
00:09:04,840 --> 00:09:07,160
Speaker 2: no matter what. And so I walk up to them

199
00:09:07,160 --> 00:09:09,559
Speaker 2: and I say, I'm a professor interested in what people

200
00:09:09,600 --> 00:09:11,920
Speaker 2: know about some questions in science. Can I ask you

201
00:09:11,960 --> 00:09:15,440
Speaker 2: a random science question? And I think ninety nine percent

202
00:09:15,480 --> 00:09:17,360
Speaker 2: of the time people say, sure, no problem.

203
00:09:17,720 --> 00:09:17,960
Speaker 1: Hmm.

204
00:09:18,240 --> 00:09:18,600
Speaker 2: Interesting.

205
00:09:18,640 --> 00:09:21,400
Speaker 1: I wonder if they think you're doing it for scientific purposes.

206
00:09:21,160 --> 00:09:23,160
Speaker 2: Aren't we isn't this part of science?

207
00:09:23,840 --> 00:09:26,640
Speaker 1: Or like, I mean, like you're running an experiment? Like

208
00:09:26,679 --> 00:09:28,959
Speaker 1: anytime you open like, hi, I'm a professor, I'm interested

209
00:09:28,960 --> 00:09:31,520
Speaker 1: in They're probably thinking you're running an experiment.

210
00:09:31,600 --> 00:09:34,240
Speaker 2: Maybe I am. Maybe this whole podcast project is actually

211
00:09:34,280 --> 00:09:36,880
Speaker 2: just an experiment. I'm writing up the paper right now,

212
00:09:37,080 --> 00:09:40,400
Speaker 2: what's your hypothesis a physicist and a cartoonist can actually

213
00:09:40,440 --> 00:09:42,680
Speaker 2: talk about science for five hundred episodes.

214
00:09:43,960 --> 00:09:50,439
Speaker 1: Sounds like a more of a there than an experiment there. Implausible,

215
00:09:50,520 --> 00:09:53,440
Speaker 1: I know, But anyways, it's an interesting question what drives

216
00:09:53,440 --> 00:09:56,319
Speaker 1: a movement of Earth's continents? Because, first of all, I

217
00:09:56,320 --> 00:09:58,840
Speaker 1: guess Earth's continents are moving. Maybe a lot of people

218
00:09:58,880 --> 00:09:59,720
Speaker 1: don't know that they're moving.

219
00:10:00,040 --> 00:10:03,880
Speaker 2: Yeah, they are moving very very slowly, so slowly that

220
00:10:03,920 --> 00:10:06,079
Speaker 2: it took us a long time to figure it out.

221
00:10:06,280 --> 00:10:08,520
Speaker 2: And even once we had the idea, it took decades

222
00:10:08,600 --> 00:10:10,920
Speaker 2: before people believed it because it seems like such a

223
00:10:11,000 --> 00:10:11,720
Speaker 2: crazy notion.

224
00:10:12,000 --> 00:10:14,560
Speaker 1: Yeah, it's pretty wild that a whole continent can move,

225
00:10:15,000 --> 00:10:18,160
Speaker 1: and I guess it happens slower than anyone can notice

226
00:10:18,200 --> 00:10:19,560
Speaker 1: in their lifetime, right.

227
00:10:19,400 --> 00:10:21,440
Speaker 2: You would think so. But actually the motion of the

228
00:10:21,480 --> 00:10:25,360
Speaker 2: continents is pretty dramatic. I mean they move like centimeters

229
00:10:25,440 --> 00:10:28,240
Speaker 2: per year, which is definitely something that you could measure.

230
00:10:28,280 --> 00:10:30,160
Speaker 2: I think it just took a long time for people

231
00:10:30,200 --> 00:10:32,640
Speaker 2: to wrap their minds around the idea that an entire

232
00:10:32,840 --> 00:10:36,360
Speaker 2: continent could be floating on an ocean of liquid magma

233
00:10:36,520 --> 00:10:38,680
Speaker 2: and sliding around the surface of the Earth is just

234
00:10:38,800 --> 00:10:41,760
Speaker 2: so far from what anybody conceived of that the data

235
00:10:41,840 --> 00:10:43,760
Speaker 2: really had to be screaming at us in our face

236
00:10:43,800 --> 00:10:44,840
Speaker 2: before we figured it out.

237
00:10:45,720 --> 00:10:48,080
Speaker 1: Well, let's maybe one of you take us back into

238
00:10:48,160 --> 00:10:50,920
Speaker 1: the history of this idea. How do we actually know

239
00:10:51,080 --> 00:10:53,360
Speaker 1: that the continents are moving? And when do we notice?

240
00:10:53,480 --> 00:10:56,160
Speaker 2: So around the turn of last century, like nineteen hundred,

241
00:10:56,480 --> 00:10:59,720
Speaker 2: there were a bunch of unexplained phenomena, things people couldn't

242
00:10:59,760 --> 00:11:01,880
Speaker 2: figure out. They didn't have a story to tell that

243
00:11:02,000 --> 00:11:05,040
Speaker 2: explained the stuff that they saw. And looking back, it

244
00:11:05,080 --> 00:11:07,200
Speaker 2: seems sort of obvious because we know the answer. But

245
00:11:07,240 --> 00:11:10,320
Speaker 2: remember that, you know, science is always running up against

246
00:11:10,440 --> 00:11:13,560
Speaker 2: the boundary of our ignorance, and there's always lots of random,

247
00:11:13,559 --> 00:11:16,199
Speaker 2: weird ideas and pass not taken. So it's very easy

248
00:11:16,240 --> 00:11:18,199
Speaker 2: to look back and see how the story came together.

249
00:11:18,200 --> 00:11:20,679
Speaker 2: It's much harder when you're standing at the forefront of

250
00:11:20,760 --> 00:11:23,240
Speaker 2: human ignorance to figure out what the clear path is.

251
00:11:23,400 --> 00:11:25,800
Speaker 2: But basically, about one hundred years ago, we saw all

252
00:11:25,840 --> 00:11:30,920
Speaker 2: these continuities between the continents, like connections between the continents

253
00:11:31,120 --> 00:11:34,559
Speaker 2: that you couldn't explain if the continents really were separate

254
00:11:34,559 --> 00:11:38,080
Speaker 2: and had always been separate. The most famous example is

255
00:11:38,120 --> 00:11:40,840
Speaker 2: how the shapes of the continents are similar. You know,

256
00:11:41,000 --> 00:11:44,320
Speaker 2: like the tip of South America the east coast matches

257
00:11:44,440 --> 00:11:47,920
Speaker 2: pretty well Africa's west coast, Like you could just imagine

258
00:11:47,960 --> 00:11:50,280
Speaker 2: sliding them together and they would like click together like

259
00:11:50,360 --> 00:11:53,160
Speaker 2: puzzle pieces. There's lots of examples of that in many

260
00:11:53,280 --> 00:11:54,360
Speaker 2: areas of research.

261
00:11:55,320 --> 00:11:58,120
Speaker 1: I mean, they're sort of like jigs or puzzle pieces

262
00:11:58,840 --> 00:11:59,839
Speaker 1: that seemed to fit together.

263
00:12:00,120 --> 00:12:03,560
Speaker 2: So there's geographic continuities where the continents can fit together.

264
00:12:03,880 --> 00:12:06,120
Speaker 2: And it's not just South America and Africa, Like it's

265
00:12:06,160 --> 00:12:09,360
Speaker 2: not too hard to imagine India and Antarctica and Australia

266
00:12:09,440 --> 00:12:12,160
Speaker 2: like clicking together. But also if you look at the

267
00:12:12,280 --> 00:12:16,679
Speaker 2: rocks on the shores of those continents, you see continuities,

268
00:12:16,760 --> 00:12:18,640
Speaker 2: Like there are layers of rock you can see in

269
00:12:18,640 --> 00:12:21,280
Speaker 2: Scotland and Ireland, and then you go to like Newfoundland

270
00:12:21,280 --> 00:12:24,240
Speaker 2: across the Atlantic and you see the same layers of rock.

271
00:12:24,640 --> 00:12:26,760
Speaker 2: It really looks like somebody, you know, cut a cake

272
00:12:27,000 --> 00:12:28,600
Speaker 2: and slid the two halves apart.

273
00:12:29,200 --> 00:12:31,480
Speaker 1: But I wonder if that's only a weird mystery if

274
00:12:31,520 --> 00:12:33,760
Speaker 1: you don't look underwater, like it's only weird if you

275
00:12:33,800 --> 00:12:37,640
Speaker 1: don't imagine that maybe that continuity continues onto the seafloor,

276
00:12:38,240 --> 00:12:39,920
Speaker 1: Like did they check for that or did they just

277
00:12:40,640 --> 00:12:41,800
Speaker 1: notice that it was the same.

278
00:12:41,920 --> 00:12:44,040
Speaker 2: The rocks under the sea floor definitely do not contain

279
00:12:44,120 --> 00:12:46,920
Speaker 2: all those same layers, And the sea floor is mostly basalt,

280
00:12:47,240 --> 00:12:49,960
Speaker 2: different kind of rock, whereas on the continent it's mostly granite.

281
00:12:50,000 --> 00:12:52,720
Speaker 2: So it's like different kinds of rock and deffinitely different layers,

282
00:12:53,200 --> 00:12:55,320
Speaker 2: and you can really fit them together, like they find

283
00:12:55,360 --> 00:12:58,240
Speaker 2: these layers on one continent and you can sign the

284
00:12:58,280 --> 00:13:01,840
Speaker 2: same kind of rocks the other side of the Atlantic.

285
00:13:02,200 --> 00:13:05,040
Speaker 2: It really is very clear that these things clicked together

286
00:13:05,520 --> 00:13:06,000
Speaker 2: in that.

287
00:13:05,880 --> 00:13:08,280
Speaker 1: Way, like in the way that they also match as

288
00:13:08,400 --> 00:13:09,520
Speaker 1: jigsaw puzzle.

289
00:13:09,280 --> 00:13:11,680
Speaker 2: Pieces, like the rocks in South America on the coast

290
00:13:11,920 --> 00:13:15,080
Speaker 2: match the rocks on the coast of Africa the west coast.

291
00:13:15,200 --> 00:13:18,760
Speaker 2: And there's other weird continuities, like there are fossils of

292
00:13:18,880 --> 00:13:23,400
Speaker 2: animals that appear in South America and in Africa, and

293
00:13:23,440 --> 00:13:26,840
Speaker 2: it's like very clearly the same animal that was one community,

294
00:13:26,920 --> 00:13:30,720
Speaker 2: you find them across the Atlantic. So either you had

295
00:13:30,760 --> 00:13:34,199
Speaker 2: like exactly the same animals evolve totally independently because the

296
00:13:34,240 --> 00:13:37,560
Speaker 2: contents were always separate or they used to be together,

297
00:13:37,679 --> 00:13:40,360
Speaker 2: the animals died a long time ago and then the

298
00:13:40,360 --> 00:13:41,680
Speaker 2: continents split.

299
00:13:41,760 --> 00:13:44,600
Speaker 1: Or maybe there was a lost continent of a planets

300
00:13:44,600 --> 00:13:47,719
Speaker 1: in the middle it was full of this animal. I mean,

301
00:13:47,760 --> 00:13:49,000
Speaker 1: I just brainstorm you here.

302
00:13:49,520 --> 00:13:52,520
Speaker 2: Right right, Maybe its ancient aliens.

303
00:13:52,000 --> 00:13:55,240
Speaker 1: Right, yeah, there you go. No, but that's what I mean,

304
00:13:55,280 --> 00:13:57,000
Speaker 1: Like I'm just trying to put my head in those

305
00:13:57,080 --> 00:13:59,120
Speaker 1: in that time, Like could that have been a possibility

306
00:13:59,120 --> 00:14:01,079
Speaker 1: for there to have been a bridge or something or

307
00:14:01,080 --> 00:14:02,520
Speaker 1: a continent in the middle of the tank.

308
00:14:02,760 --> 00:14:05,360
Speaker 2: Perhaps, But there's lots of different examples. It's not just

309
00:14:05,480 --> 00:14:08,720
Speaker 2: like South America to Africa, Like this fossil evidence of

310
00:14:08,760 --> 00:14:13,360
Speaker 2: this land reptile called Listrosaurus, which you see in Antarctica

311
00:14:13,440 --> 00:14:16,640
Speaker 2: and in India and in Africa because those pieces used

312
00:14:16,640 --> 00:14:19,160
Speaker 2: to click together. And then there's like fossils of this

313
00:14:19,280 --> 00:14:23,080
Speaker 2: fern called Glysopteris, which is found in all the southern

314
00:14:23,120 --> 00:14:25,360
Speaker 2: continents to show that they were once joined. And then

315
00:14:25,360 --> 00:14:28,640
Speaker 2: there's this like fresh water reptile to Mesosaurus, which is

316
00:14:28,680 --> 00:14:30,960
Speaker 2: connected from the south of Africa to the south of

317
00:14:30,960 --> 00:14:33,880
Speaker 2: South America. So like one single bridge wouldn't do it.

318
00:14:33,920 --> 00:14:36,040
Speaker 2: You need like a lot of bridges or you just

319
00:14:36,040 --> 00:14:37,480
Speaker 2: got to stick the continents together.

320
00:14:37,880 --> 00:14:40,200
Speaker 1: Hmmm. All right, So those were some clues. What were

321
00:14:40,240 --> 00:14:41,000
Speaker 1: some other clues.

322
00:14:41,080 --> 00:14:45,160
Speaker 2: Another really fascinating clue was looking underwater. They did study

323
00:14:45,160 --> 00:14:48,240
Speaker 2: the rocks on the seafloor, and what they found were

324
00:14:48,280 --> 00:14:52,240
Speaker 2: these weird stripes of magnetism. Like the rocks on the

325
00:14:52,240 --> 00:14:55,160
Speaker 2: sea floor sometimes contain this stuff called magnetite, which is

326
00:14:55,320 --> 00:14:59,360
Speaker 2: very magnetic material and it's influenced by the magnetic field

327
00:14:59,400 --> 00:15:02,240
Speaker 2: of the Earth. And they looked to the magnetic field

328
00:15:02,480 --> 00:15:05,320
Speaker 2: of these rocks and they found this weird zebra striping,

329
00:15:05,640 --> 00:15:08,400
Speaker 2: Like there's a stripe that's pointing one way, and then

330
00:15:08,400 --> 00:15:10,960
Speaker 2: another stripe that's pointing the opposite way, and then another

331
00:15:10,960 --> 00:15:13,680
Speaker 2: stripe that's pointing back the first way. So it's like

332
00:15:13,720 --> 00:15:17,200
Speaker 2: the rocks have these alternating stripes of magnetic field sort

333
00:15:17,200 --> 00:15:18,440
Speaker 2: of frozen into them.

334
00:15:18,680 --> 00:15:22,080
Speaker 1: They have like a pattern the writ in the magnetism.

335
00:15:22,160 --> 00:15:24,600
Speaker 2: Yeah, they're like these zebra stripes, you know, like a

336
00:15:24,720 --> 00:15:26,760
Speaker 2: stripe pointing towards the north pole, and then a stripe

337
00:15:26,760 --> 00:15:29,000
Speaker 2: pouring towards a south pole, and then stripe pointing towards

338
00:15:29,000 --> 00:15:31,200
Speaker 2: the north pole. So there are all these weird things

339
00:15:31,200 --> 00:15:34,160
Speaker 2: that nobody could explain all these weird clues that, like,

340
00:15:34,160 --> 00:15:36,600
Speaker 2: you know, we couldn't tell a story that made sense

341
00:15:36,680 --> 00:15:40,600
Speaker 2: of what we were seeing. The geographic clues, the geological cues,

342
00:15:40,640 --> 00:15:43,880
Speaker 2: the biographic clues, the magnetic field clues, all of these

343
00:15:43,880 --> 00:15:45,000
Speaker 2: things didn't make sense.

344
00:15:45,400 --> 00:15:48,560
Speaker 1: How wide were these stripes? Like are they huven size

345
00:15:48,640 --> 00:15:50,240
Speaker 1: or are they like miles wide?

346
00:15:50,320 --> 00:15:53,280
Speaker 2: These things are not tiny, you know, they're like kilometers

347
00:15:53,280 --> 00:15:56,240
Speaker 2: wide in some cases, but they show weird patterns. They're

348
00:15:56,240 --> 00:15:59,240
Speaker 2: like not like exactly perfect stripes. They show some ridges

349
00:15:59,280 --> 00:16:02,200
Speaker 2: and some twists, which we'll talk about later, but they're

350
00:16:02,240 --> 00:16:03,800
Speaker 2: pretty big, m I see.

351
00:16:03,840 --> 00:16:06,320
Speaker 1: So it was really kind of like there were all

352
00:16:06,360 --> 00:16:09,000
Speaker 1: these puzzle pieces lying around in the table, and like,

353
00:16:09,080 --> 00:16:11,400
Speaker 1: if you thought about it, you start to figure out

354
00:16:11,440 --> 00:16:13,480
Speaker 1: that not just the shapes can fit, but like maybe

355
00:16:13,600 --> 00:16:16,440
Speaker 1: like the picture of the pattern in the puzzle pieces

356
00:16:16,880 --> 00:16:19,280
Speaker 1: seemed to make sense if you spect them together.

357
00:16:19,520 --> 00:16:23,240
Speaker 2: Yeah, exactly. And it was nineteen twelve when a guy

358
00:16:23,320 --> 00:16:25,880
Speaker 2: named Weggner first proposed this idea. He's like, I can

359
00:16:25,960 --> 00:16:28,720
Speaker 2: explain all of these things with the simple idea that

360
00:16:28,760 --> 00:16:32,840
Speaker 2: the continents were once all together, that they drifted apart.

361
00:16:33,440 --> 00:16:36,440
Speaker 2: So he proposed this concept of Pangaea that a couple

362
00:16:36,480 --> 00:16:39,240
Speaker 2: of one hundred million years ago, all the continents we know

363
00:16:39,360 --> 00:16:43,360
Speaker 2: now were actually congealed into one big super continent and

364
00:16:43,400 --> 00:16:45,760
Speaker 2: they've drifted apart over those years.

365
00:16:46,280 --> 00:16:49,000
Speaker 1: M like they were once part of a super band,

366
00:16:49,200 --> 00:16:51,600
Speaker 1: but then they disbanded and they of course they played

367
00:16:51,680 --> 00:16:53,360
Speaker 1: rock music right exactly.

368
00:16:53,600 --> 00:16:55,680
Speaker 2: And now we know actually that that's only the most

369
00:16:55,760 --> 00:16:59,040
Speaker 2: recent example. Like Pangea existed around two hundred and fifty

370
00:16:59,120 --> 00:17:02,800
Speaker 2: million years ago, but we reconstructed even further back into

371
00:17:02,880 --> 00:17:05,280
Speaker 2: the past. There were super continents like a billion years

372
00:17:05,320 --> 00:17:08,440
Speaker 2: ago and two billion years ago. It's really a crazy

373
00:17:08,560 --> 00:17:14,160
Speaker 2: chaotic story. Pangaea is only the most recent super continent. Whoa.

374
00:17:14,240 --> 00:17:16,840
Speaker 2: But at the time people were like, what your bonkers?

375
00:17:17,040 --> 00:17:20,200
Speaker 2: How could the continents move? They're like these huge piles

376
00:17:20,200 --> 00:17:22,719
Speaker 2: of rock. There's no way to like slide them around.

377
00:17:23,119 --> 00:17:24,879
Speaker 2: You know, when you're doing a puzzle on a table,

378
00:17:25,160 --> 00:17:27,359
Speaker 2: you have gaps between the pieces so you can slide

379
00:17:27,400 --> 00:17:30,600
Speaker 2: them around. If all the pieces were like already stuck together,

380
00:17:30,600 --> 00:17:33,320
Speaker 2: it'd be pretty hard to move them around to adjust

381
00:17:33,320 --> 00:17:34,080
Speaker 2: their locations.

382
00:17:34,280 --> 00:17:37,560
Speaker 1: Yeah, I guess like the mechanism for how those continents

383
00:17:37,640 --> 00:17:40,119
Speaker 1: are moving is kind of hard to fathom right, because

384
00:17:40,119 --> 00:17:43,960
Speaker 1: the Earth we at least at the time, No, it's

385
00:17:44,000 --> 00:17:46,040
Speaker 1: all made out of rock, right, even under the ocean

386
00:17:46,040 --> 00:17:48,240
Speaker 1: it's rock, And so like, how do you move dying

387
00:17:48,320 --> 00:17:49,720
Speaker 1: mountains exactly?

388
00:17:49,720 --> 00:17:52,199
Speaker 2: People knew that the Earth's crust was solid, and like

389
00:17:52,280 --> 00:17:54,600
Speaker 2: fifty or so years ago, people had figured out that

390
00:17:54,640 --> 00:17:57,399
Speaker 2: the Earth was solid underneath. It was very dense and

391
00:17:57,400 --> 00:17:59,840
Speaker 2: there's probably a liquid core. Were actually talked about that

392
00:18:00,119 --> 00:18:03,199
Speaker 2: our episode about how to measure the gravitational constant. In

393
00:18:03,280 --> 00:18:04,879
Speaker 2: order to do that, we basically had to measure the

394
00:18:04,920 --> 00:18:07,359
Speaker 2: density of the Earth and understand that it was not

395
00:18:07,440 --> 00:18:10,000
Speaker 2: like hollow, it was actually filled with rock. But yeah,

396
00:18:10,000 --> 00:18:12,760
Speaker 2: the basic question is if you have a solid crust,

397
00:18:12,800 --> 00:18:15,240
Speaker 2: even if it's liquid underneath, how do the pieces of

398
00:18:15,280 --> 00:18:18,240
Speaker 2: the solid crust slide right, like you have a balloon

399
00:18:18,359 --> 00:18:20,879
Speaker 2: it's filled with liquid, doesn't mean that like the surface

400
00:18:20,920 --> 00:18:23,600
Speaker 2: of the balloon can slide around and rearrange the pieces, right,

401
00:18:23,680 --> 00:18:26,639
Speaker 2: There's no like room for things to move. So there

402
00:18:26,680 --> 00:18:28,600
Speaker 2: was a lot of skepticism about this idea.

403
00:18:29,080 --> 00:18:30,399
Speaker 1: M They thought it was crazy.

404
00:18:30,560 --> 00:18:32,560
Speaker 2: Yeah, and at the time that had an even more

405
00:18:32,640 --> 00:18:36,120
Speaker 2: bonder sounding idea for like how mountains formed right now

406
00:18:36,119 --> 00:18:39,320
Speaker 2: of course, we understand mountains form often when plates smash

407
00:18:39,400 --> 00:18:42,720
Speaker 2: into each other, like the Himalayas are from India slamming

408
00:18:42,760 --> 00:18:45,560
Speaker 2: into the Eurasian plate. At the time, they thought that

409
00:18:45,640 --> 00:18:49,480
Speaker 2: mountains formed vertically as the planet was cooling. It was

410
00:18:49,560 --> 00:18:53,400
Speaker 2: like shrinking as it was cooling, and things like bubbled up.

411
00:18:53,640 --> 00:18:56,880
Speaker 1: Hmmm, sort of like shrink rab what was left after

412
00:18:56,960 --> 00:18:57,840
Speaker 1: U shrink wrap something?

413
00:18:57,920 --> 00:19:00,720
Speaker 2: Yeah, exactly, that it wasn't that mountain and so rising,

414
00:19:00,760 --> 00:19:02,399
Speaker 2: but that the rest of the surface was sort of

415
00:19:02,440 --> 00:19:06,320
Speaker 2: like shrinking as the planet cooled, revealing these mountains.

416
00:19:06,840 --> 00:19:08,960
Speaker 1: Well, it sounds like today we know a little bit better,

417
00:19:09,119 --> 00:19:12,200
Speaker 1: and so let's get into how these continents are actually

418
00:19:12,320 --> 00:19:15,720
Speaker 1: able to move around the planet and what is powering

419
00:19:15,960 --> 00:19:32,000
Speaker 1: this movement. But first let's take a quick break. All right,

420
00:19:32,040 --> 00:19:35,800
Speaker 1: we're asking the question what drives the movement of Earth's continents,

421
00:19:35,840 --> 00:19:37,680
Speaker 1: and we talked about how they are moving and how

422
00:19:37,720 --> 00:19:39,480
Speaker 1: we sort of figured that out because they are sort

423
00:19:39,480 --> 00:19:42,800
Speaker 1: of like puzzle pieces. The continents, the shape of them

424
00:19:42,840 --> 00:19:44,919
Speaker 1: and also the rocks and the patterns on top of

425
00:19:44,920 --> 00:19:48,040
Speaker 1: them are like a giant jigsaw puzzle, which I guess

426
00:19:48,320 --> 00:19:50,840
Speaker 1: makes me ask the question, which is the corner piece

427
00:19:50,920 --> 00:19:54,120
Speaker 1: Daniel in a spherical puzzle, how do you even get

428
00:19:54,119 --> 00:19:55,639
Speaker 1: started if you don't have corner pieces?

429
00:19:55,720 --> 00:19:58,119
Speaker 2: Antarctica? Always start with Antarctica.

430
00:19:58,200 --> 00:20:01,440
Speaker 1: But it's all white and it looks the same as

431
00:20:01,440 --> 00:20:02,760
Speaker 1: the pieces in the North Pole.

432
00:20:04,760 --> 00:20:06,920
Speaker 2: Yeah, that's true. It's a puzzle, but.

433
00:20:06,840 --> 00:20:08,439
Speaker 1: It sounds that we sort of figured it out. So

434
00:20:08,480 --> 00:20:11,159
Speaker 1: we know that the continents are moving, and they have

435
00:20:11,240 --> 00:20:14,440
Speaker 1: been moving, and before only about two hundred and something

436
00:20:14,520 --> 00:20:17,159
Speaker 1: million years ago, all the continents that we know today

437
00:20:17,240 --> 00:20:19,880
Speaker 1: were all crushed together into one super continent.

438
00:20:20,040 --> 00:20:23,000
Speaker 2: Yeah, around two hundred and fifty million years ago, And

439
00:20:23,119 --> 00:20:26,240
Speaker 2: this was a really revolutionary idea at the time. You know,

440
00:20:26,280 --> 00:20:29,520
Speaker 2: this is an example science historians talk about a scientific

441
00:20:29,560 --> 00:20:34,359
Speaker 2: revolution where a concept is intuitive and ingrained and widely

442
00:20:34,400 --> 00:20:38,879
Speaker 2: accepted and then eventually overthrown by the data. You know

443
00:20:38,920 --> 00:20:42,240
Speaker 2: that we're confronted with the facts and forced to change

444
00:20:42,280 --> 00:20:44,439
Speaker 2: the way we think about the universe. And you know,

445
00:20:44,440 --> 00:20:47,479
Speaker 2: people who talk about like science conspiracies and all this stuff.

446
00:20:47,720 --> 00:20:50,080
Speaker 2: This is a great example of how science really does

447
00:20:50,320 --> 00:20:52,880
Speaker 2: change when faced with the data. It takes a while,

448
00:20:52,920 --> 00:20:54,960
Speaker 2: and it takes a lot of data. But scientists like

449
00:20:55,040 --> 00:20:57,879
Speaker 2: to be right. They like to explain what we are seeing.

450
00:20:57,960 --> 00:21:00,439
Speaker 2: A don't likes to cover things up or gauge in

451
00:21:00,480 --> 00:21:03,880
Speaker 2: planet wide conspiracies. Everybody wants to be Wagoner, the guy

452
00:21:03,920 --> 00:21:06,920
Speaker 2: who came up with a revolutionary idea that changed the

453
00:21:06,960 --> 00:21:09,600
Speaker 2: way we think about the entire history of our planet.

454
00:21:09,800 --> 00:21:12,119
Speaker 1: Yeah. I think it's more like a Scientists like to

455
00:21:12,160 --> 00:21:13,440
Speaker 1: prove others wrong. Yo.

456
00:21:13,560 --> 00:21:18,159
Speaker 2: Yeah. Scientists are people, which means they are motivated by

457
00:21:18,160 --> 00:21:21,240
Speaker 2: the same things people are motivated by, sometimes pettiness and

458
00:21:21,280 --> 00:21:22,480
Speaker 2: sometimes glamor. Yeah.

459
00:21:22,480 --> 00:21:24,040
Speaker 1: And I think in this case you're saying like their

460
00:21:24,080 --> 00:21:26,920
Speaker 1: motivation sort of aligns with the idea of finding out

461
00:21:26,920 --> 00:21:28,200
Speaker 1: what the truth is exactly.

462
00:21:28,320 --> 00:21:29,520
Speaker 2: Scientists want to be right.

463
00:21:29,840 --> 00:21:32,840
Speaker 1: Yeah, they gained nothing by a worldwide conspiracy.

464
00:21:33,040 --> 00:21:35,119
Speaker 2: I mean, maybe we gain like cool robes and a

465
00:21:35,160 --> 00:21:37,720
Speaker 2: secret handshake, but that doesn't seem to be worth it. Yeah.

466
00:21:38,400 --> 00:21:39,960
Speaker 1: Secret handshakes, Yeah, like.

467
00:21:40,119 --> 00:21:43,080
Speaker 2: Pales in comparison to discovering the truth about the universe.

468
00:21:43,240 --> 00:21:44,439
Speaker 1: You just want to be part of the club.

469
00:21:45,359 --> 00:21:47,040
Speaker 2: I don't actually care about being part of the club.

470
00:21:47,080 --> 00:21:48,119
Speaker 2: I just want to know the truth.

471
00:21:48,280 --> 00:21:49,600
Speaker 1: You just want to prove others wrong.

472
00:21:50,560 --> 00:21:53,000
Speaker 2: But in this case, it took like fifty years for

473
00:21:53,119 --> 00:21:56,360
Speaker 2: people to really come around to this idea because there

474
00:21:56,359 --> 00:21:58,600
Speaker 2: were a lot of puzzles before people figured out how

475
00:21:58,640 --> 00:22:00,520
Speaker 2: it all worked. There were a few more piece of

476
00:22:00,880 --> 00:22:04,600
Speaker 2: evidence that started to sway people towards the direction of

477
00:22:04,640 --> 00:22:07,880
Speaker 2: this idea. More things we learned about what was happening

478
00:22:08,080 --> 00:22:10,159
Speaker 2: on the surface of the Earth that made the continental

479
00:22:10,240 --> 00:22:11,879
Speaker 2: drift theory make more sense.

480
00:22:12,240 --> 00:22:13,960
Speaker 1: Yeah, And I guess it's not something that you can

481
00:22:14,080 --> 00:22:17,840
Speaker 1: like test right or make a prediction about, right, It's

482
00:22:17,840 --> 00:22:19,879
Speaker 1: somebody you can see, Like, I think the continents are moving,

483
00:22:19,920 --> 00:22:22,040
Speaker 1: and in a hundred million years, this is what the

484
00:22:22,119 --> 00:22:24,440
Speaker 1: Earth is going to look like, and you'll see I'll

485
00:22:24,440 --> 00:22:27,600
Speaker 1: be right. You just kind of have to like look

486
00:22:27,640 --> 00:22:30,160
Speaker 1: at the data and be convinced by the data, right, Yeah.

487
00:22:30,200 --> 00:22:32,480
Speaker 2: Actually, I think there is a prediction for what the

488
00:22:32,520 --> 00:22:34,560
Speaker 2: continents are going to look like, and they put it

489
00:22:34,640 --> 00:22:37,440
Speaker 2: up on a satellite orbiting the Earth. The idea being

490
00:22:37,480 --> 00:22:40,320
Speaker 2: that if humans all die out and aliens come to

491
00:22:40,600 --> 00:22:44,080
Speaker 2: visit in a hundred million years and find this satellite,

492
00:22:44,240 --> 00:22:46,160
Speaker 2: it would be like evidence that we knew what we

493
00:22:46,160 --> 00:22:47,199
Speaker 2: were doing or not.

494
00:22:48,400 --> 00:22:50,760
Speaker 1: I feel like that it's pretty risky. We could be

495
00:22:50,800 --> 00:22:53,720
Speaker 1: totally off and then we'll be known throughout the trinity

496
00:22:53,720 --> 00:22:56,120
Speaker 1: in the cosmic community. How wrong we were.

497
00:22:57,080 --> 00:22:59,320
Speaker 2: Yeah, that's why they died out because they failed to

498
00:22:59,359 --> 00:23:01,360
Speaker 2: predict the coal drift right.

499
00:23:01,480 --> 00:23:04,399
Speaker 1: Yeah, they couldn't even get that right, something as small

500
00:23:04,400 --> 00:23:05,400
Speaker 1: as continent's moving.

501
00:23:05,600 --> 00:23:07,600
Speaker 2: Well, it's a really fun story because along the way

502
00:23:07,640 --> 00:23:11,000
Speaker 2: we learned so much about our planet. One mental obstacle

503
00:23:11,040 --> 00:23:13,639
Speaker 2: people had to accepting the idea of a continental drift

504
00:23:14,040 --> 00:23:15,960
Speaker 2: was the idea of the age of the Earth. People

505
00:23:16,000 --> 00:23:18,760
Speaker 2: had this concept that the Earth was pretty old, but

506
00:23:18,840 --> 00:23:20,680
Speaker 2: the current thinking of the time was like the Earth

507
00:23:20,800 --> 00:23:23,720
Speaker 2: was only around maybe ten million years old or so.

508
00:23:24,040 --> 00:23:26,560
Speaker 2: They did this calculation to estimate how long it would

509
00:23:26,560 --> 00:23:29,200
Speaker 2: take the Earth to cool from a ball of hot

510
00:23:29,280 --> 00:23:32,960
Speaker 2: magma to its current temperature. And if you just think

511
00:23:33,000 --> 00:23:36,520
Speaker 2: about like radiating heat out into space, then it only

512
00:23:36,600 --> 00:23:39,199
Speaker 2: takes like a few tens of millions of years to

513
00:23:39,320 --> 00:23:41,600
Speaker 2: cool the Earth down to where it is today. So

514
00:23:41,640 --> 00:23:44,600
Speaker 2: the continental drift theory required a much older Earth, and

515
00:23:44,640 --> 00:23:46,520
Speaker 2: that was hard to jibe with this idea that the

516
00:23:46,560 --> 00:23:49,000
Speaker 2: Earth only takes a few tens of millions of years

517
00:23:49,000 --> 00:23:49,440
Speaker 2: to cool.

518
00:23:50,359 --> 00:23:52,720
Speaker 1: Well, I guess maybe it depends on your theory or

519
00:23:52,720 --> 00:23:55,679
Speaker 1: what you know about how the Earth started, Like did

520
00:23:55,720 --> 00:23:58,960
Speaker 1: the Earth start with a bunch of molten rock or

521
00:23:59,119 --> 00:24:01,719
Speaker 1: did it start with like free floating rocks that then

522
00:24:01,840 --> 00:24:02,879
Speaker 1: gathered and melted.

523
00:24:03,080 --> 00:24:05,520
Speaker 2: It started from pebbles and gas and dust and all

524
00:24:05,560 --> 00:24:08,360
Speaker 2: this stuff in the very early solar system, which then

525
00:24:08,480 --> 00:24:11,719
Speaker 2: formed gravitationally. But the gravitational pressure was pretty intense. I mean,

526
00:24:11,720 --> 00:24:14,800
Speaker 2: it's intense enough to like spark fusion at the center

527
00:24:14,840 --> 00:24:17,560
Speaker 2: of the Sun. It's not hot enough to get fusion

528
00:24:17,600 --> 00:24:19,200
Speaker 2: going at the center of the Earth, but it's definitely

529
00:24:19,240 --> 00:24:20,959
Speaker 2: hot enough to melt those rocks.

530
00:24:21,440 --> 00:24:23,639
Speaker 1: And so you're saying, like, that's how you assume. And

531
00:24:23,880 --> 00:24:26,440
Speaker 1: if that's the only thing you assumed that was happening

532
00:24:26,440 --> 00:24:28,920
Speaker 1: with a giant rock floating in space, then the Earth

533
00:24:28,960 --> 00:24:31,679
Speaker 1: by now should have been you know, kind of stone

534
00:24:31,680 --> 00:24:32,439
Speaker 1: cold exactly.

535
00:24:32,520 --> 00:24:35,040
Speaker 2: But around that same time, like the very end of

536
00:24:35,080 --> 00:24:37,879
Speaker 2: the eighteen hundreds, very beginning of the nineteen hundreds, we

537
00:24:37,960 --> 00:24:42,720
Speaker 2: discovered radioactivity like beckerel left blob uranium on a photographic plate,

538
00:24:42,800 --> 00:24:45,639
Speaker 2: came back after the weekend, saw it was fogged. The

539
00:24:45,760 --> 00:24:49,240
Speaker 2: cures studied radioactivity was right around that time we understood it.

540
00:24:49,280 --> 00:24:52,400
Speaker 2: So then people realized that radioactive decay inside the Earth

541
00:24:52,520 --> 00:24:55,760
Speaker 2: was also keeping the Earth warm. The Earth is like

542
00:24:55,800 --> 00:25:00,320
Speaker 2: a giant nuclear battery where these nuclear decays are heating

543
00:25:00,400 --> 00:25:03,199
Speaker 2: up the Earth and keeping it toasty. So actually the

544
00:25:03,280 --> 00:25:05,600
Speaker 2: Earth had to be much much older than just a

545
00:25:05,640 --> 00:25:08,719
Speaker 2: few tens of millions of years to have cool this much.

546
00:25:09,560 --> 00:25:12,200
Speaker 1: Well, let's talk about the continental driss then, I guess,

547
00:25:12,240 --> 00:25:14,960
Speaker 1: how is it that the continents can move? Like what's

548
00:25:15,000 --> 00:25:17,600
Speaker 1: going on there? Are they not fixed in place? And

549
00:25:17,920 --> 00:25:19,280
Speaker 1: what are they moving on top of?

550
00:25:19,520 --> 00:25:22,040
Speaker 2: So there's a lot of action happening at the edges

551
00:25:22,080 --> 00:25:24,679
Speaker 2: of these continental plates. So like the Earth has a

552
00:25:24,720 --> 00:25:27,280
Speaker 2: surface which is a crust. We call it the lithosphere,

553
00:25:27,320 --> 00:25:29,720
Speaker 2: and it's solid, but it's cracked into pieces, and at

554
00:25:29,760 --> 00:25:32,359
Speaker 2: the edges stuff can happen. There's some places at the

555
00:25:32,440 --> 00:25:35,120
Speaker 2: edges where they're being pushed apart. The plates are being

556
00:25:35,160 --> 00:25:37,879
Speaker 2: pushed further apart, and this is for example, in the

557
00:25:37,920 --> 00:25:41,040
Speaker 2: middle of the Atlantic Ocean. There's this ridge that was

558
00:25:41,080 --> 00:25:44,440
Speaker 2: discovered in the nineteen forties where magma is bubbling up

559
00:25:44,440 --> 00:25:47,440
Speaker 2: from within the Earth and pushing these two plates apart

560
00:25:47,480 --> 00:25:50,760
Speaker 2: from each other, So the Atlantic Ocean is growing. That's

561
00:25:50,800 --> 00:25:52,679
Speaker 2: one example of how we get like motion at the

562
00:25:52,760 --> 00:25:53,720
Speaker 2: edges of these plates.

563
00:25:54,240 --> 00:25:55,879
Speaker 1: I think you're saying that, like the Earth, it's a

564
00:25:55,920 --> 00:25:59,040
Speaker 1: little bit maybe like an egg right where it's like

565
00:25:59,119 --> 00:26:02,879
Speaker 1: it's circulars but the inside, the outside is kind of

566
00:26:02,880 --> 00:26:06,240
Speaker 1: hard and crusty like a shell, and the inside is

567
00:26:06,280 --> 00:26:09,040
Speaker 1: sort of soft and liquid in a way.

568
00:26:09,160 --> 00:26:12,399
Speaker 2: The inside is definitely hotter and softer. Just below the

569
00:26:12,440 --> 00:26:15,080
Speaker 2: crust is the mantle, and the upper mantle is like

570
00:26:15,200 --> 00:26:18,360
Speaker 2: technically a solid, but because it's under such great pressure,

571
00:26:18,400 --> 00:26:21,320
Speaker 2: it can actually very slowly flow, and as you go

572
00:26:21,400 --> 00:26:23,359
Speaker 2: further and further down, it gets to be more and

573
00:26:23,400 --> 00:26:26,720
Speaker 2: more liquid. So yeah, things can slide and squish underneath

574
00:26:26,760 --> 00:26:28,320
Speaker 2: the surface of the Earth. But one of the big

575
00:26:28,400 --> 00:26:31,080
Speaker 2: questions was, you know, even if things are liquid, how

576
00:26:31,080 --> 00:26:33,440
Speaker 2: do you get room to move? Right, Like, if the

577
00:26:33,480 --> 00:26:36,280
Speaker 2: pieces are fixed in shape, then how do they move?

578
00:26:36,320 --> 00:26:38,280
Speaker 2: And the answer is they're not fixed in shape. The

579
00:26:38,320 --> 00:26:41,399
Speaker 2: plates both grow and shrink, so they grow on sides

580
00:26:41,440 --> 00:26:45,480
Speaker 2: where there's like creation of new surface, like when you're

581
00:26:45,520 --> 00:26:48,480
Speaker 2: creating new earth underneath the ocean, it's like magma is

582
00:26:48,520 --> 00:26:51,679
Speaker 2: bubbling up and becoming new surface. That's like extending the

583
00:26:51,720 --> 00:26:54,359
Speaker 2: size of those plates. And then on the other side

584
00:26:54,400 --> 00:26:58,040
Speaker 2: you actually have destruction of the plates, Like the plates

585
00:26:58,040 --> 00:27:01,320
Speaker 2: are going underneath each other cyclic back into the earth.

586
00:27:01,720 --> 00:27:04,760
Speaker 2: So it's sort of like very slow moving conveyor belt

587
00:27:05,119 --> 00:27:07,960
Speaker 2: where you're destroying a plate on one side and creating

588
00:27:08,000 --> 00:27:09,440
Speaker 2: more plate on the other side.

589
00:27:10,400 --> 00:27:13,040
Speaker 1: So, going back to our egg analogy, I think what

590
00:27:13,080 --> 00:27:15,200
Speaker 1: you're saying is that, like the crust of the earth

591
00:27:15,520 --> 00:27:18,960
Speaker 1: is not one whole piece like an eggshell. It's actually

592
00:27:19,000 --> 00:27:21,000
Speaker 1: cracked in a lot of places. But then even if

593
00:27:21,040 --> 00:27:24,680
Speaker 1: you crack it in break it the shell into several pieces,

594
00:27:24,960 --> 00:27:27,800
Speaker 1: you still have to wonder like how those pieces can

595
00:27:27,880 --> 00:27:30,360
Speaker 1: move about. The reason is that they're sort of floating

596
00:27:30,400 --> 00:27:34,560
Speaker 1: on semi liquid mantle right on rock that is fluid.

597
00:27:34,720 --> 00:27:37,120
Speaker 1: And also they're not just doing that, but they're also

598
00:27:37,160 --> 00:27:40,520
Speaker 1: sort of like being created and destroyed at the same time.

599
00:27:40,600 --> 00:27:41,760
Speaker 1: These giant plates.

600
00:27:41,560 --> 00:27:44,919
Speaker 2: Exactly, each plate is like flowing in some direction on

601
00:27:45,000 --> 00:27:47,360
Speaker 2: top of liquid, and where it hits another plate, it's

602
00:27:47,400 --> 00:27:51,240
Speaker 2: being subducted. It's like getting pushed down back into the earth.

603
00:27:51,800 --> 00:27:54,720
Speaker 2: Those are like the deep trenches in the ocean, like

604
00:27:54,760 --> 00:27:58,040
Speaker 2: the Baryanas Trench. In other places, on the west coast

605
00:27:58,080 --> 00:28:01,520
Speaker 2: of South America and on the east coast of Asia,

606
00:28:01,600 --> 00:28:03,720
Speaker 2: there are these deep trenches where the ocean floor is

607
00:28:03,760 --> 00:28:07,960
Speaker 2: getting pushed down into the earth, and on the other side,

608
00:28:08,320 --> 00:28:11,080
Speaker 2: new plate is being created, like the mid Atlantic Ridge

609
00:28:11,080 --> 00:28:14,080
Speaker 2: is creating new plates. So that's why, like the Atlantic

610
00:28:14,119 --> 00:28:16,920
Speaker 2: Ocean is growing and the Pacific Ocean is shrinking.

611
00:28:17,320 --> 00:28:19,280
Speaker 1: Right, So like if you have one of these plates

612
00:28:19,760 --> 00:28:21,480
Speaker 1: that let's say like you live in an island on

613
00:28:21,520 --> 00:28:23,280
Speaker 1: top of one of these plates, and let's say the

614
00:28:23,280 --> 00:28:26,760
Speaker 1: whole plate is flowing to the right, that means that

615
00:28:26,840 --> 00:28:30,080
Speaker 1: like on the left side of your plate, there's more

616
00:28:30,160 --> 00:28:33,160
Speaker 1: plate growing. Right, there's like more more of it coming

617
00:28:33,240 --> 00:28:36,280
Speaker 1: up from the ground being created, pushing the whole plate

618
00:28:36,320 --> 00:28:38,000
Speaker 1: to the right. But then on the right side of

619
00:28:38,000 --> 00:28:40,520
Speaker 1: the plate it's running into another plate and so then

620
00:28:40,560 --> 00:28:43,200
Speaker 1: it's getting destroyed there or maybe it might not be right.

621
00:28:43,280 --> 00:28:45,360
Speaker 1: It's usually like one of them goes under.

622
00:28:45,400 --> 00:28:48,640
Speaker 2: Yeah, the subduction, so one of them goes under. Exactly

623
00:28:48,960 --> 00:28:51,640
Speaker 2: where they meet, and we can tell where the edge

624
00:28:51,680 --> 00:28:53,400
Speaker 2: of these plates are, where the cracks are on the

625
00:28:53,400 --> 00:28:57,160
Speaker 2: Earth's surface because we can measure the seismic activity. Basically

626
00:28:57,200 --> 00:29:00,719
Speaker 2: there's earthquakes where these plates meet because they're grinding and

627
00:29:00,760 --> 00:29:03,080
Speaker 2: sliding away from each other, or one is going under

628
00:29:03,120 --> 00:29:07,760
Speaker 2: the other one, or there's like huge volcanoes underground creating

629
00:29:08,040 --> 00:29:10,120
Speaker 2: new surface. And so if you look at like this

630
00:29:10,280 --> 00:29:13,120
Speaker 2: seismic activity pattern, you just ask like where are all

631
00:29:13,240 --> 00:29:16,760
Speaker 2: micro earthquakes on the Earth. Then they don't just happen

632
00:29:16,840 --> 00:29:19,840
Speaker 2: randomly all over the Earth to happen in these lines.

633
00:29:20,000 --> 00:29:22,080
Speaker 2: If you put a dot on the Earth wherever there's

634
00:29:22,080 --> 00:29:25,239
Speaker 2: an earthquake, they come out to make these patterns that

635
00:29:25,320 --> 00:29:28,040
Speaker 2: show you the edges of the plates, like the cracks

636
00:29:28,040 --> 00:29:28,720
Speaker 2: in the eggshell.

637
00:29:29,280 --> 00:29:31,000
Speaker 1: You can hear the continents crunching.

638
00:29:31,160 --> 00:29:34,040
Speaker 2: Kind of Yeah, it's actually interesting bit of history. In

639
00:29:34,080 --> 00:29:37,600
Speaker 2: like the nineteen sixties, the US and the USSR, we're

640
00:29:37,640 --> 00:29:41,040
Speaker 2: doing underground testing of nuclear weapons and one of the

641
00:29:41,080 --> 00:29:43,680
Speaker 2: best ways to detect underground testing is to build a

642
00:29:43,760 --> 00:29:48,680
Speaker 2: worldwise network of seismographs to see when testing is happening.

643
00:29:48,760 --> 00:29:51,080
Speaker 2: And so that's why the US invested in a huge

644
00:29:51,080 --> 00:29:53,720
Speaker 2: network of these seismographs, and that's one of the ways

645
00:29:53,720 --> 00:29:56,640
Speaker 2: that we learned about all of these micro earthquakes that

646
00:29:56,680 --> 00:29:58,800
Speaker 2: showed us where the plates were mmmmm.

647
00:30:00,440 --> 00:30:01,800
Speaker 1: But then we use that for sign.

648
00:30:03,600 --> 00:30:06,600
Speaker 2: Well. As usual, the science budget is a tiny, tiny

649
00:30:06,680 --> 00:30:10,200
Speaker 2: fraction of like the military budget or the intelligence budget,

650
00:30:10,360 --> 00:30:13,800
Speaker 2: or even like the consumer electronics budget. So we're always

651
00:30:13,840 --> 00:30:16,720
Speaker 2: trying to be clever in ways to like leverage the

652
00:30:16,840 --> 00:30:20,240
Speaker 2: huge resources of other sectors the economy for the benefit

653
00:30:20,280 --> 00:30:20,760
Speaker 2: of science.

654
00:30:20,880 --> 00:30:22,880
Speaker 1: I think you can also tell where these plates meet

655
00:30:22,960 --> 00:30:26,400
Speaker 1: by looking at more volcanoes, right, Like most volcanoes are

656
00:30:26,560 --> 00:30:28,440
Speaker 1: where two plates intersect.

657
00:30:28,080 --> 00:30:31,360
Speaker 2: Exactly earthquakes and volcanoes. And if you look underwater at

658
00:30:31,400 --> 00:30:34,200
Speaker 2: the Atlantic you can see this huge ridge which is

659
00:30:34,240 --> 00:30:38,360
Speaker 2: basically a line of volcanoes where the Earth is cracked

660
00:30:38,400 --> 00:30:41,480
Speaker 2: and it's seeping up and that magma then becomes new

661
00:30:41,600 --> 00:30:45,160
Speaker 2: surface of the ocean. And that actually explains what's going

662
00:30:45,200 --> 00:30:48,440
Speaker 2: on with the magnetic striping, because this new rock is

663
00:30:48,520 --> 00:30:51,920
Speaker 2: forming and cooling, but it's happening over time, and so

664
00:30:52,360 --> 00:30:54,640
Speaker 2: as you get further from this mid Atlantic ridge, the

665
00:30:54,760 --> 00:30:57,360
Speaker 2: rock gets older and older. So what the rocks are

666
00:30:57,400 --> 00:31:02,560
Speaker 2: doing are tracking the Earth's magnetic over time. I remember,

667
00:31:02,560 --> 00:31:05,040
Speaker 2: the Earth's magnetic field is not constant. The North Pole

668
00:31:05,080 --> 00:31:07,320
Speaker 2: today is not where the North Pole has always been,

669
00:31:07,880 --> 00:31:10,560
Speaker 2: and over the last millions of years it has flipped

670
00:31:10,600 --> 00:31:13,880
Speaker 2: a bunch of times. So basically this magnetic striping is

671
00:31:13,920 --> 00:31:17,680
Speaker 2: a record of the flipping of Earth's magnetic field because

672
00:31:17,680 --> 00:31:20,080
Speaker 2: it's like influenced by the magnetic field and locks in

673
00:31:20,120 --> 00:31:22,760
Speaker 2: whatever it was at the time, and then it doesn't change.

674
00:31:23,120 --> 00:31:26,160
Speaker 1: Hmmm. It's like the Earth's magnet field paints on these

675
00:31:26,240 --> 00:31:28,720
Speaker 1: rocks sort of right, and so as new rocks for

676
00:31:28,800 --> 00:31:31,160
Speaker 1: coming up to get painted differently, and it logs how

677
00:31:31,200 --> 00:31:33,320
Speaker 1: many times Santa Claus had to move over the years,

678
00:31:34,240 --> 00:31:36,640
Speaker 1: which is probably a big pain for him and Missus claws.

679
00:31:36,880 --> 00:31:39,800
Speaker 2: Yeah, but it's a silver fascinating like measurement of the

680
00:31:39,840 --> 00:31:42,680
Speaker 2: history of the Earth. It's like rings on a tree, right,

681
00:31:42,720 --> 00:31:45,000
Speaker 2: It like tells you how many times this has happened.

682
00:31:45,440 --> 00:31:48,200
Speaker 2: And because these things are not perfect stripes, you can

683
00:31:48,280 --> 00:31:52,200
Speaker 2: use them to reconstruct how the ocean floor has grown, right,

684
00:31:52,240 --> 00:31:54,640
Speaker 2: it tells you like where it's grown faster and where

685
00:31:54,640 --> 00:31:57,880
Speaker 2: it's grown slower. You should totally google a picture of

686
00:31:57,920 --> 00:32:01,800
Speaker 2: the magnetic field striping of the It's really fascinating. They've

687
00:32:01,880 --> 00:32:04,920
Speaker 2: used this to reconstruct like the super continents a billion

688
00:32:04,960 --> 00:32:07,600
Speaker 2: years ago and two billion years ago. It tells you

689
00:32:07,640 --> 00:32:11,640
Speaker 2: the whole history, the dramatic, violent history of the continents

690
00:32:11,680 --> 00:32:12,280
Speaker 2: on the surface.

691
00:32:13,120 --> 00:32:15,120
Speaker 1: Yeah, it's pretty dramatic. I guess if you look at

692
00:32:15,120 --> 00:32:18,120
Speaker 1: it from a long term point of view, right, Like

693
00:32:18,160 --> 00:32:19,760
Speaker 1: if you were to take a movie of the Earth

694
00:32:20,120 --> 00:32:22,240
Speaker 1: and fast forward it, you know, by millions of years,

695
00:32:22,440 --> 00:32:25,680
Speaker 1: you would see these giant continents like crashing to each

696
00:32:25,720 --> 00:32:26,640
Speaker 1: other and split apart.

697
00:32:26,840 --> 00:32:28,760
Speaker 2: Yeah, but the surprising thing to me is that it's

698
00:32:28,800 --> 00:32:33,120
Speaker 2: not that slow. It moves in centimeters per year. In

699
00:32:33,160 --> 00:32:37,080
Speaker 2: some places, it's like eleven centimeters per year of subduction.

700
00:32:37,280 --> 00:32:39,280
Speaker 2: I mean, that's not so tiny. Like if your neighbor's

701
00:32:39,280 --> 00:32:41,960
Speaker 2: house moved closer to your house by centimeters per year,

702
00:32:42,120 --> 00:32:43,720
Speaker 2: it wouldn't take very many years.

703
00:32:43,600 --> 00:32:46,800
Speaker 1: Before you noticed, unless you really like your neighbors and

704
00:32:47,000 --> 00:32:49,440
Speaker 1: are considered moving in with them. But I think the

705
00:32:49,520 --> 00:32:53,520
Speaker 1: question that was posted originally was what drives the movement

706
00:32:53,600 --> 00:32:56,120
Speaker 1: of these continents? And so like the question is like

707
00:32:56,240 --> 00:32:58,600
Speaker 1: why are they moving? Anyways? Like we know how they're moving.

708
00:32:58,680 --> 00:33:01,160
Speaker 1: We talked about the mechanism makes a move, but like

709
00:33:01,360 --> 00:33:03,720
Speaker 1: why are they moving? Is maybe the question? And so

710
00:33:03,840 --> 00:33:07,360
Speaker 1: let's get into that big question what drives these continental

711
00:33:07,400 --> 00:33:10,840
Speaker 1: shifts and drifts? But first let's take another quick break.

712
00:33:23,360 --> 00:33:26,840
Speaker 1: All right, we're asking the question what is making Earth's

713
00:33:26,880 --> 00:33:30,880
Speaker 1: continents move? Because they're moving, and they're moving none as

714
00:33:31,320 --> 00:33:34,760
Speaker 1: insignificant rate a few centimeters a year, which doesn't seem

715
00:33:34,840 --> 00:33:36,760
Speaker 1: like a lot, but over millions of years, it can

716
00:33:36,840 --> 00:33:40,720
Speaker 1: make continents split apart, crash into each other, make new continents.

717
00:33:40,960 --> 00:33:44,040
Speaker 1: Pretty dramatic and juicy history there that the Earth has.

718
00:33:44,120 --> 00:33:46,880
Speaker 1: And so now we're asking the question, what is making

719
00:33:47,080 --> 00:33:51,280
Speaker 1: these big continental motions, what is powering it? And why

720
00:33:51,320 --> 00:33:53,240
Speaker 1: isn't the Earth just staying the same.

721
00:33:53,360 --> 00:33:55,800
Speaker 2: Yeah, it's really amazing how the surface of the Earth

722
00:33:55,920 --> 00:33:59,880
Speaker 2: reveals what's going on underneath. Beneath the hard crust, this

723
00:34:00,080 --> 00:34:03,480
Speaker 2: cracked eggshell of a surface of the Earth is a

724
00:34:03,600 --> 00:34:07,520
Speaker 2: crazy amount of energy of heat and motion of the mantle.

725
00:34:07,600 --> 00:34:10,080
Speaker 2: So we have the outer mantle, which is pretty solid

726
00:34:10,120 --> 00:34:13,200
Speaker 2: but actually does flow, but below that things get liquid.

727
00:34:13,440 --> 00:34:16,960
Speaker 2: And what's happening there is convection, like things heat up

728
00:34:17,000 --> 00:34:19,600
Speaker 2: and so they rise, things cool down and so they sink.

729
00:34:19,640 --> 00:34:21,960
Speaker 2: It's sort of like a big bubbling pot of tomato

730
00:34:22,000 --> 00:34:24,200
Speaker 2: sauce where you have like bubbles coming up and things

731
00:34:24,280 --> 00:34:26,919
Speaker 2: sinking and things are mixing. Right when you have soup

732
00:34:27,000 --> 00:34:29,360
Speaker 2: bubbling on the stove, it doesn't just sit there like

733
00:34:29,520 --> 00:34:33,280
Speaker 2: mixes itself, because things rise, they get hot and sink

734
00:34:33,320 --> 00:34:36,160
Speaker 2: as they cool, and that same thing is happening inside

735
00:34:36,160 --> 00:34:40,400
Speaker 2: the Earth, creating these convection cells, which are basically huge

736
00:34:40,600 --> 00:34:44,319
Speaker 2: spinning currents of magma underneath the Earth that drive the

737
00:34:44,360 --> 00:34:45,960
Speaker 2: conveyor belt on the surface.

738
00:34:46,200 --> 00:34:48,560
Speaker 1: I guess it pushes like it creates, like let's say,

739
00:34:48,600 --> 00:34:51,440
Speaker 1: a giant flow forms or giant bubble forms in the

740
00:34:51,480 --> 00:34:54,440
Speaker 1: Earth center. That's going to put pressure on the mantle,

741
00:34:54,640 --> 00:34:58,239
Speaker 1: which is then creating pressure on the eggshell crust. Right.

742
00:34:58,320 --> 00:35:00,960
Speaker 2: So imagine beneath the center of the plantic for example,

743
00:35:01,200 --> 00:35:04,840
Speaker 2: there's a hot spot, and so magma gets extra heated

744
00:35:04,880 --> 00:35:07,200
Speaker 2: there and what happens, Well, it's going to rise, and

745
00:35:07,239 --> 00:35:09,319
Speaker 2: it's going to bubble up, and there's a crack there

746
00:35:09,360 --> 00:35:11,920
Speaker 2: between the tectonic plates, so it's going to come out,

747
00:35:12,080 --> 00:35:14,840
Speaker 2: and so it's pushing those plates apart. And on the

748
00:35:14,920 --> 00:35:17,400
Speaker 2: other side the subduction where the plates are meeting and

749
00:35:17,440 --> 00:35:20,960
Speaker 2: banging into each other and getting pushed below, those are cooler, right,

750
00:35:21,000 --> 00:35:24,560
Speaker 2: and so as that cooler surface gets pushed into the magma,

751
00:35:24,960 --> 00:35:28,959
Speaker 2: it falls, it sinks, right. Because it's cooler, cold things

752
00:35:29,000 --> 00:35:31,520
Speaker 2: sink and hot things rise. So now you get this

753
00:35:31,600 --> 00:35:34,600
Speaker 2: circular pattern cold things sinking on the edge of it

754
00:35:34,840 --> 00:35:36,200
Speaker 2: hot things rising in.

755
00:35:36,160 --> 00:35:39,480
Speaker 1: The middle, So then all of that energy that's moving

756
00:35:39,480 --> 00:35:43,399
Speaker 1: the continent comes from the energy kind of boiling under

757
00:35:43,400 --> 00:35:44,920
Speaker 1: the surface of the earth exactly.

758
00:35:44,920 --> 00:35:46,920
Speaker 2: And there's lots of really interesting questions there, Like for

759
00:35:46,960 --> 00:35:50,000
Speaker 2: a long time, people thought that the dominant force was

760
00:35:50,040 --> 00:35:53,280
Speaker 2: the seafloor spreading, that this bubbling up of the heat

761
00:35:53,520 --> 00:35:55,440
Speaker 2: was really driving it, and it was like pushing the

762
00:35:55,480 --> 00:35:58,080
Speaker 2: plates and it was crunching them together, and the subduction

763
00:35:58,280 --> 00:36:01,239
Speaker 2: was really just like the plates getting slammed together ultimately

764
00:36:01,280 --> 00:36:04,760
Speaker 2: from the seafloor spreading. That was like the dominant idea

765
00:36:04,840 --> 00:36:07,319
Speaker 2: for the first few decades after the whole concept of

766
00:36:07,320 --> 00:36:10,080
Speaker 2: plate technonics was accepted, But more recently people have been

767
00:36:10,120 --> 00:36:13,360
Speaker 2: convinced of the opposite, that it's the subduction that's actually dominant,

768
00:36:13,400 --> 00:36:16,200
Speaker 2: that it's the crunching of plates and pulling them underneath

769
00:36:16,440 --> 00:36:18,960
Speaker 2: that's really making it happen. That it's more of a

770
00:36:19,000 --> 00:36:20,840
Speaker 2: pull than a push.

771
00:36:21,440 --> 00:36:24,279
Speaker 1: Like people thought that what was driving the movement was

772
00:36:24,560 --> 00:36:27,640
Speaker 1: the new land being created pushing the plates outwards. But

773
00:36:27,880 --> 00:36:30,760
Speaker 1: you're saying it's more like maybe it's where they're dipping

774
00:36:31,080 --> 00:36:34,240
Speaker 1: underneath the surface that's actually pulling the whole continent away

775
00:36:35,120 --> 00:36:38,240
Speaker 1: and then where there's a crack left, then new ground

776
00:36:38,280 --> 00:36:39,000
Speaker 1: gets formed there.

777
00:36:39,080 --> 00:36:41,439
Speaker 2: Yeah, exactly, And that sort of makes more sense because

778
00:36:41,480 --> 00:36:43,799
Speaker 2: the surface is not that solid, so like what it's

779
00:36:43,840 --> 00:36:46,040
Speaker 2: easier to do to pull a carpet or to push

780
00:36:46,080 --> 00:36:48,799
Speaker 2: on a carpet, So pulling like at the edges of

781
00:36:48,800 --> 00:36:50,520
Speaker 2: the plates sort of makes a little bit more sense

782
00:36:50,520 --> 00:36:52,240
Speaker 2: to me. But it's really a question of like energy

783
00:36:52,280 --> 00:36:56,200
Speaker 2: dynamics and force balancing. Where is this really happening? And

784
00:36:56,239 --> 00:36:58,919
Speaker 2: you know, one of the deepest questions is like why

785
00:36:58,960 --> 00:37:01,680
Speaker 2: do you get these convicts the cells in the first place,

786
00:37:01,920 --> 00:37:04,960
Speaker 2: How do these cells get started? How many are there,

787
00:37:05,280 --> 00:37:08,200
Speaker 2: what is their structure. It's like we'd like to understand

788
00:37:08,320 --> 00:37:11,680
Speaker 2: the boiling tomato soup that's underneath the surface of the Earth.

789
00:37:11,800 --> 00:37:13,680
Speaker 1: And I think some of this boiling is also what

790
00:37:13,800 --> 00:37:16,319
Speaker 1: makes the Earth's magnetic field too, isn't it.

791
00:37:16,360 --> 00:37:19,160
Speaker 2: The Earth's magnetic field is definitely connected to the flow

792
00:37:19,360 --> 00:37:22,400
Speaker 2: of all this stuff inside the Earth. We don't understand

793
00:37:22,400 --> 00:37:24,600
Speaker 2: how much is connected to like the mantle or the

794
00:37:24,640 --> 00:37:26,759
Speaker 2: outer core, which is a little bit more metallic, but

795
00:37:26,880 --> 00:37:29,880
Speaker 2: definitely we need flow inside the Earth to generate the

796
00:37:29,920 --> 00:37:32,520
Speaker 2: magnetic field and It's an interesting connection, right, because the

797
00:37:32,520 --> 00:37:36,000
Speaker 2: magnetic field also flips, and that leaves a pattern on

798
00:37:36,120 --> 00:37:38,880
Speaker 2: the seafloor. So the whole thing is like a big, complicated,

799
00:37:38,920 --> 00:37:39,760
Speaker 2: beautiful dance.

800
00:37:40,280 --> 00:37:43,399
Speaker 1: Hmmm, the earth shuffle. But then I guess a question

801
00:37:43,480 --> 00:37:45,040
Speaker 1: that you can ask is like how long is that

802
00:37:45,080 --> 00:37:46,960
Speaker 1: going to keep going? Like is the Earth going to

803
00:37:47,040 --> 00:37:49,200
Speaker 1: run out of you know, inner boil? Is it going

804
00:37:49,239 --> 00:37:51,600
Speaker 1: to run out of energy inside? And then everything's going

805
00:37:51,680 --> 00:37:52,880
Speaker 1: to just stay still?

806
00:37:53,120 --> 00:37:55,560
Speaker 2: The Earth will eventually cool, right. This depends on the

807
00:37:55,600 --> 00:37:59,520
Speaker 2: Earth maintaining its temperature. And while the radioactive decay inside

808
00:37:59,560 --> 00:38:02,320
Speaker 2: the Earth is keeping us warm like a nice battery,

809
00:38:02,800 --> 00:38:05,600
Speaker 2: it's not enough. We are radiating more heat out into

810
00:38:05,640 --> 00:38:09,000
Speaker 2: space than it's being generated by those decays. So they think,

811
00:38:09,080 --> 00:38:11,920
Speaker 2: like in about a billion and a half years, the

812
00:38:11,960 --> 00:38:14,400
Speaker 2: temperature of the mantle won't be high enough anymore for

813
00:38:14,560 --> 00:38:17,200
Speaker 2: this kind of flow, and we think the place tectonics

814
00:38:17,200 --> 00:38:19,560
Speaker 2: will cease. So we got like another billion and a

815
00:38:19,600 --> 00:38:20,560
Speaker 2: half years.

816
00:38:20,480 --> 00:38:23,279
Speaker 1: A billion and a half years before the crust kind

817
00:38:23,280 --> 00:38:26,359
Speaker 1: of freezes in place. Right, Whatever we look like then

818
00:38:26,440 --> 00:38:28,000
Speaker 1: is how we're going to look like until the end

819
00:38:28,040 --> 00:38:29,799
Speaker 1: of time, or at least until the sun eats us up.

820
00:38:29,880 --> 00:38:32,160
Speaker 2: It's like another billion years of musical chairs and then

821
00:38:32,160 --> 00:38:34,240
Speaker 2: eventually the music just stops.

822
00:38:34,640 --> 00:38:38,640
Speaker 1: Now, is that heat from the center of the Earth significant, Like,

823
00:38:38,880 --> 00:38:41,319
Speaker 1: are we going to freeze or does? Right now? A

824
00:38:41,320 --> 00:38:42,839
Speaker 1: lot of our heat comes from the Sun.

825
00:38:43,040 --> 00:38:45,000
Speaker 2: The temperature of the surface of the Earth is not

826
00:38:45,120 --> 00:38:48,120
Speaker 2: too affected by what's going on inside the Earth. That's

827
00:38:48,160 --> 00:38:50,480
Speaker 2: more dominated by the Sun and the atmosphere and those

828
00:38:50,560 --> 00:38:53,400
Speaker 2: kind of effects. So even if the Earth's continents do

829
00:38:53,520 --> 00:38:55,680
Speaker 2: freeze in place, we can stay warm from the Sun.

830
00:38:55,840 --> 00:38:56,720
Speaker 2: That's not an issue.

831
00:38:56,800 --> 00:38:58,600
Speaker 1: Maybe a bigger issue by then will be that we

832
00:38:58,640 --> 00:38:59,960
Speaker 1: won't have a magnetic field.

833
00:39:01,239 --> 00:39:03,160
Speaker 2: Yeah, where the Sun is getting brighter and brighter, so

834
00:39:03,160 --> 00:39:05,440
Speaker 2: we're probably just going to overheat. In a billion years,

835
00:39:05,440 --> 00:39:07,880
Speaker 2: the Sun is going to be significantly brighter than it

836
00:39:07,920 --> 00:39:08,400
Speaker 2: is today.

837
00:39:08,560 --> 00:39:10,640
Speaker 1: And we've seen this kind of thing happen in other

838
00:39:10,680 --> 00:39:11,520
Speaker 1: planets too, right.

839
00:39:11,560 --> 00:39:13,920
Speaker 2: Well, Earth is the only planet in the Solar System

840
00:39:14,040 --> 00:39:17,400
Speaker 2: with active tectonic plates. We think there's evidence that the

841
00:39:17,440 --> 00:39:21,080
Speaker 2: Moon and Mars both once had tectonic activity, though they

842
00:39:21,080 --> 00:39:23,799
Speaker 2: are smaller than the Earth and they cool faster, and

843
00:39:23,880 --> 00:39:26,680
Speaker 2: so both of them are basically already frozen in place.

844
00:39:26,960 --> 00:39:29,520
Speaker 1: Well, there aren't that many rocky planets to begin with.

845
00:39:29,600 --> 00:39:30,720
Speaker 1: There's like three or four.

846
00:39:30,640 --> 00:39:34,319
Speaker 2: Right, Yeah, but they're also rocky moons, right, like Ganymede

847
00:39:34,360 --> 00:39:37,680
Speaker 2: and Io. These are planets, they're geologically active, but we

848
00:39:37,719 --> 00:39:40,680
Speaker 2: don't see tectonic plates on them either. You need like

849
00:39:40,840 --> 00:39:43,839
Speaker 2: just the right mix of temperature and also water. Like

850
00:39:44,000 --> 00:39:46,560
Speaker 2: water is really crucial to making this happen because it

851
00:39:46,640 --> 00:39:49,719
Speaker 2: weakens the crust. When the rocks are cooling, if there's

852
00:39:49,800 --> 00:39:53,600
Speaker 2: water around, it changes the chemical composition of it, which

853
00:39:53,640 --> 00:39:55,799
Speaker 2: makes the crust a little weaker, which allows for this

854
00:39:55,840 --> 00:39:59,200
Speaker 2: sort of like conveyor belt destruction and subduction. For example,

855
00:39:59,320 --> 00:40:02,040
Speaker 2: Venus is still internally hot. We think there's like oceans

856
00:40:02,040 --> 00:40:05,319
Speaker 2: of magma inside, but doesn't have tectonic plates the same

857
00:40:05,320 --> 00:40:08,440
Speaker 2: way Earth does, and we think that probably it's because

858
00:40:08,480 --> 00:40:11,400
Speaker 2: it lacks water. It doesn't have any surface oceans to

859
00:40:11,440 --> 00:40:12,080
Speaker 2: make this happen.

860
00:40:12,160 --> 00:40:14,640
Speaker 1: Yeah, it's just reaen about this. Water actually makes rock

861
00:40:14,800 --> 00:40:16,760
Speaker 1: melt at a lower temperature.

862
00:40:16,360 --> 00:40:18,920
Speaker 2: Right, yeah, So it encourages the flow, right. Essentially, it

863
00:40:18,960 --> 00:40:21,680
Speaker 2: weakens the rock and makes it more liquid. So the

864
00:40:21,719 --> 00:40:24,080
Speaker 2: fact that we have oceans and tectonic plates is not

865
00:40:24,160 --> 00:40:27,040
Speaker 2: a coincidence. You need really both of those things to happen.

866
00:40:27,239 --> 00:40:29,880
Speaker 2: Venus is a crazy planet anyway. They think like a

867
00:40:29,920 --> 00:40:34,560
Speaker 2: billion years ago there was a complete volcanic resurfacing, meaning

868
00:40:34,640 --> 00:40:38,440
Speaker 2: volcanoes completely created a new surface of the planet basically

869
00:40:38,440 --> 00:40:41,160
Speaker 2: just by spewing magma everywhere. But we don't think there

870
00:40:41,160 --> 00:40:43,480
Speaker 2: are plate tectonics on Venus.

871
00:40:43,600 --> 00:40:47,680
Speaker 1: Hmmm, weird. Interesting now, And you said this happens in

872
00:40:47,960 --> 00:40:50,480
Speaker 1: moons like our moon, but then also other moons in

873
00:40:50,560 --> 00:40:51,160
Speaker 1: other planets.

874
00:40:51,320 --> 00:40:53,799
Speaker 2: Yeah, so the our moon probably had plate tectonics in

875
00:40:53,800 --> 00:40:57,359
Speaker 2: the past, but now it's cooled. Io, which is one

876
00:40:57,360 --> 00:40:59,160
Speaker 2: of the moons of Jupiter, and it's about the same

877
00:40:59,280 --> 00:41:02,799
Speaker 2: size as our our moon is still actively volcanic, Like

878
00:41:02,880 --> 00:41:06,560
Speaker 2: the voyager saw several volcanic plumes rising like hundreds of

879
00:41:06,600 --> 00:41:10,000
Speaker 2: kilometers above the surface. So there's definitely stuff going on

880
00:41:10,120 --> 00:41:12,960
Speaker 2: inside there, and it's probably mostly due to like thermal

881
00:41:13,160 --> 00:41:16,960
Speaker 2: energy from tidal forces from Jupiter, which produces like convection

882
00:41:17,040 --> 00:41:19,360
Speaker 2: in the interior of Io. It's like getting squeezed by

883
00:41:19,440 --> 00:41:23,719
Speaker 2: Jupiter's gravity. But we haven't actually seen plate tectonics on

884
00:41:23,800 --> 00:41:26,040
Speaker 2: Io as well, though, you know, Io has not been

885
00:41:26,040 --> 00:41:27,560
Speaker 2: studied in great depth yet.

886
00:41:28,120 --> 00:41:30,160
Speaker 1: So it seems like, it's kind of rare to have

887
00:41:30,320 --> 00:41:33,000
Speaker 1: plate tectonics or is it just that the other planets

888
00:41:33,000 --> 00:41:34,280
Speaker 1: had it but then they stop?

889
00:41:34,360 --> 00:41:36,320
Speaker 2: It might be both. It might not be an automatic

890
00:41:36,440 --> 00:41:38,040
Speaker 2: thing for every planet to have it. You need the

891
00:41:38,080 --> 00:41:42,200
Speaker 2: right combination of temperature and convection underneath the surface and

892
00:41:42,400 --> 00:41:44,880
Speaker 2: water on the surface to weaken the crust. So it

893
00:41:44,880 --> 00:41:47,200
Speaker 2: doesn't happen all the time. But you know, if it

894
00:41:47,239 --> 00:41:50,040
Speaker 2: happened on the Moon and on Mars and on Earth,

895
00:41:50,040 --> 00:41:53,120
Speaker 2: that means it's not super duper rare. Another question is like, well,

896
00:41:53,160 --> 00:41:55,640
Speaker 2: how important is it? Does it really matter if you

897
00:41:55,680 --> 00:41:58,239
Speaker 2: have plate tectonics. It's kind of fascinating on Earth that

898
00:41:58,280 --> 00:42:02,239
Speaker 2: the continent's drifting apart changes the evolution of animals because

899
00:42:02,280 --> 00:42:04,480
Speaker 2: if like a community gets split in half, now you

900
00:42:04,520 --> 00:42:07,120
Speaker 2: have two of them isolated and they can evolve in

901
00:42:07,160 --> 00:42:09,919
Speaker 2: separate directions. We don't know what would have been the

902
00:42:09,960 --> 00:42:13,520
Speaker 2: history of life on Earth if we didn't have plate tectonics.

903
00:42:13,560 --> 00:42:15,640
Speaker 2: It might be very very different. Hmm.

904
00:42:16,239 --> 00:42:19,000
Speaker 1: We wouldn't have kangaroos.

905
00:42:18,920 --> 00:42:22,719
Speaker 2: For example. Right, Sometimes it's important to have an isolated

906
00:42:22,719 --> 00:42:25,719
Speaker 2: community so they have times develop some new capacity before

907
00:42:25,719 --> 00:42:27,960
Speaker 2: they have to compete with the mainland. This is called

908
00:42:28,000 --> 00:42:31,840
Speaker 2: like biogeographic islands and communities. It's a whole field of

909
00:42:31,960 --> 00:42:36,040
Speaker 2: study and it's actually replicated and really interestingly in artificial intelligence,

910
00:42:36,120 --> 00:42:39,160
Speaker 2: sometimes when you're training neural networks and you give them

911
00:42:39,160 --> 00:42:41,880
Speaker 2: a hard new task, you create like a subpool of

912
00:42:41,880 --> 00:42:44,400
Speaker 2: these neural networks, so they train on this hard new

913
00:42:44,440 --> 00:42:46,520
Speaker 2: task in isolation before they have to come back and

914
00:42:46,680 --> 00:42:49,880
Speaker 2: compete with the other neural networks on the mainland. So

915
00:42:49,960 --> 00:42:52,600
Speaker 2: you know, having islands and having divisions between these things

916
00:42:52,640 --> 00:42:56,480
Speaker 2: can be really helpful for creating diversity and weirdness in

917
00:42:56,520 --> 00:42:57,200
Speaker 2: life on Earth.

918
00:42:58,640 --> 00:43:02,000
Speaker 1: I guess it can affect life. Is it necessary to life?

919
00:43:02,160 --> 00:43:04,480
Speaker 2: Fascinating question I wish we knew the answer to. The

920
00:43:04,480 --> 00:43:06,600
Speaker 2: only way to really figure that out is to see

921
00:43:06,600 --> 00:43:09,359
Speaker 2: a bunch of other planets. So we're not there yet,

922
00:43:09,400 --> 00:43:11,799
Speaker 2: but people are hoping that eventually we'll be able to

923
00:43:11,840 --> 00:43:16,000
Speaker 2: study the surface of exo planets planets in other solar systems,

924
00:43:16,280 --> 00:43:18,319
Speaker 2: so we get more data and we could see like, oh, look,

925
00:43:18,360 --> 00:43:20,480
Speaker 2: there happens to be life only on planets that once

926
00:43:20,520 --> 00:43:23,640
Speaker 2: had plate tectonics. Maybe there's a connection there. We don't know,

927
00:43:24,000 --> 00:43:26,080
Speaker 2: but it's something we might figure out in the future

928
00:43:26,440 --> 00:43:28,759
Speaker 2: if we can see and study other planets.

929
00:43:29,160 --> 00:43:32,040
Speaker 1: M But I guess there's no mechanism for how it

930
00:43:32,120 --> 00:43:34,839
Speaker 1: might help life that we know about. Or maybe being

931
00:43:34,880 --> 00:43:37,000
Speaker 1: in a super continent helps or I don't know. Do

932
00:43:37,000 --> 00:43:39,360
Speaker 1: we have any ideas how that might affect the formation

933
00:43:39,440 --> 00:43:40,160
Speaker 1: of life, the.

934
00:43:40,040 --> 00:43:43,879
Speaker 2: Formation of life, the actual genesis of life from non

935
00:43:43,960 --> 00:43:46,680
Speaker 2: living materials. No, I don't think the continants can really

936
00:43:46,680 --> 00:43:50,200
Speaker 2: play a role. But it might help develop more complex life.

937
00:43:50,280 --> 00:43:53,040
Speaker 2: It might give life an opportunity to develop in weird

938
00:43:53,080 --> 00:43:57,720
Speaker 2: new directions. Maybe it's crucial for civilization and intelligence. Who knows.

939
00:43:58,000 --> 00:44:00,120
Speaker 2: We're really just speculating.

940
00:44:00,360 --> 00:44:03,520
Speaker 1: I see, just arguing about what counts as a continent

941
00:44:04,360 --> 00:44:07,279
Speaker 1: or not. You're saying might have the driven evolution for

942
00:44:07,400 --> 00:44:08,560
Speaker 1: us to be better arguers.

943
00:44:09,040 --> 00:44:11,360
Speaker 2: Probably started a bunch of wars. You know, wars have

944
00:44:11,400 --> 00:44:13,279
Speaker 2: definitely been fought over dumber stuff than that.

945
00:44:13,520 --> 00:44:15,400
Speaker 1: Wars and podcast episodes.

946
00:44:16,520 --> 00:44:18,560
Speaker 2: Wars on podcast episodes.

947
00:44:18,200 --> 00:44:20,239
Speaker 1: Crucial on the way to enlightenment.

948
00:44:20,280 --> 00:44:22,480
Speaker 2: As a speak, well, you know, the culmination of all

949
00:44:22,480 --> 00:44:25,280
Speaker 2: of evolution of life on Earth? Is this podcast? So yes?

950
00:44:25,320 --> 00:44:27,720
Speaker 1: Absolutely, yeah, of course we're here to explain the universe.

951
00:44:27,760 --> 00:44:30,440
Speaker 1: I mean, how much more evolved?

952
00:44:30,440 --> 00:44:32,600
Speaker 2: Can it get Before we explain the universe, we got

953
00:44:32,600 --> 00:44:34,920
Speaker 2: to explain the Earth. You know, it's fastened into me.

954
00:44:35,040 --> 00:44:38,880
Speaker 2: How much we still don't understand and how recent any

955
00:44:38,920 --> 00:44:41,880
Speaker 2: of this understanding is. As of just one hundred years ago,

956
00:44:42,120 --> 00:44:45,000
Speaker 2: nobody believed this continental drift theory, and now it's an

957
00:44:45,160 --> 00:44:50,439
Speaker 2: essential part of modern geology and geography and biology. It's

958
00:44:50,480 --> 00:44:52,680
Speaker 2: like the theory of evolution. You know, once you see it,

959
00:44:52,760 --> 00:44:55,520
Speaker 2: you can't unsee it. It's just so obvious. But it

960
00:44:55,520 --> 00:44:58,520
Speaker 2: takes a while to absorb these crazy new ideas. But

961
00:44:58,520 --> 00:45:00,520
Speaker 2: those are the best moments in science, right when we

962
00:45:00,600 --> 00:45:03,360
Speaker 2: have to pivot to something totally bonkers and new, because

963
00:45:03,360 --> 00:45:04,880
Speaker 2: that's just the way the data is.

964
00:45:05,360 --> 00:45:07,239
Speaker 1: Yeah, and it sounds like there are still a lot

965
00:45:07,239 --> 00:45:10,120
Speaker 1: of mysteries left to answer about how the Earth moves

966
00:45:10,160 --> 00:45:12,440
Speaker 1: around and what it's doing under the surface, which means

967
00:45:12,440 --> 00:45:15,520
Speaker 1: that we may be wrong right now, right and who

968
00:45:15,560 --> 00:45:17,640
Speaker 1: knows what we're going to discover about the future.

969
00:45:17,440 --> 00:45:20,000
Speaker 2: Exactly, not just the future, but also the past. They've

970
00:45:20,040 --> 00:45:23,600
Speaker 2: done these reconstructions of these super continents from two billion

971
00:45:23,640 --> 00:45:26,280
Speaker 2: years ago, one of them is called Nuna, and another

972
00:45:26,320 --> 00:45:29,680
Speaker 2: super continent from a billion years ago called Rhodinia, but

973
00:45:29,880 --> 00:45:32,200
Speaker 2: that whole history could also be wrong. We may need

974
00:45:32,239 --> 00:45:36,720
Speaker 2: to rewrite the entire history of life and continents on Earth.

975
00:45:37,160 --> 00:45:39,640
Speaker 2: It's going to be fascinating to see what people figure out.

976
00:45:39,920 --> 00:45:42,120
Speaker 1: Yeah, maybe the continents just looked like a giant smiley

977
00:45:42,120 --> 00:45:45,160
Speaker 1: face before and the Earth was hoping that it would

978
00:45:45,160 --> 00:45:50,240
Speaker 1: freeze out with smiling. But then you know, the universe

979
00:45:50,280 --> 00:45:51,160
Speaker 1: took too long to take.

980
00:45:51,000 --> 00:45:53,320
Speaker 2: The picture like a giant continent until selfie.

981
00:45:53,680 --> 00:45:57,400
Speaker 1: All right, Well again, an interesting dive into our own planet,

982
00:45:57,560 --> 00:45:59,920
Speaker 1: this thing we're all standing on, and how it's moving

983
00:46:00,280 --> 00:46:03,040
Speaker 1: underneath our feet, and how there are still deep mysteries

984
00:46:03,280 --> 00:46:05,759
Speaker 1: as deep as the center of the Earth going on

985
00:46:06,080 --> 00:46:07,000
Speaker 1: right under.

986
00:46:06,880 --> 00:46:08,759
Speaker 2: Us, and how long it can take to figure out

987
00:46:08,760 --> 00:46:10,720
Speaker 2: the story of our very own planet.

988
00:46:10,920 --> 00:46:13,719
Speaker 1: We hope you enjoyed that. Thanks for joining us, See

989
00:46:13,760 --> 00:46:14,239
Speaker 1: you next night.

990
00:46:22,280 --> 00:46:25,080
Speaker 2: Thanks for listening, and remember that Daniel and Jorge Explain

991
00:46:25,160 --> 00:46:29,160
Speaker 2: the Universe is a production of iHeartRadio. For more podcasts

992
00:46:29,160 --> 00:46:33,800
Speaker 2: from iHeartRadio, visit the iHeartRadio app, Apple Podcasts, or wherever

993
00:46:33,880 --> 00:46:35,600
Speaker 2: you listen to your favorite shows.