Shadowing Practice: When Siberia thaws, what emerges? - Learn English Speaking with Video
Creating lesson...
1
You may have heard there's something lurking in the Arctic.
2
In a remote part of Siberia.
3
Hidden deep within the permafrost.
4
A giant virus was unearthed.
5
Dideljegernches.
6
So-called zombie viruses.
7
Zombie.
8
Time-traveling.
9
Zombie viruses.
10
That have survived for thousands of years.
11
And scientists are worried.
12
They can unleash catastrophic consequences.
13
That doesn't sound great, and I noticed that a bunch of our comments also mention this threat.
14
So I decided to look into it.
15
How much should we be worried about a new pandemic emerging from the permafrost?
16
My research took me from mammoth meat to diamond mines to lost cities beneath the sea.
17
And what I eventually found entombed in the permafrost was more fascinating than frightening.
18
I'd like to share with you Adam's five steps for successful ancient zombie pandemic.
19
Successful for humans or successful for the zombie virus? the microbe.
20
So this is from the perspective of the microbe.
21
Oh, fun.
22
If you're an ancient bacteria or a virus and you want to make it big, your first step is to actually get preserved in the permafrost.
23
Next, you have to survive being thawed and then come into contact with a human host.
24
You need to successfully infect that human, but that's not enough.
25
To cause a pandemic, you have to be able to spread human to human through the population.
26
So I just want to go through each of these steps
27
and talk about how likely they each are so we can see how much danger there actually is.
28
Here is one of the earliest depictions of a woolly mammoth.
29
Do you notice anything missing?
30
The trunk!
31
The trunk!
32
It's missing a trunk!
33
It's missing a trunk.
34
This was not drawn by a scientist.
35
This was drawn by a merchant who just happened to see a mammoth carcass.
36
And it's actually not his fault that there is no trunk
37
because it turns out that whenever Whenever a mammoth is exposed like this, most of the time its fleshy bits are immediately gobbled up by arctic foxes and other carnivores.
38
In 1907 in Siberia, on the bank of this winding river, a mammoth was finally discovered with its trunk intact,
39
and they actually set guards to protect this carcass.
40
And I bring this up because I think it shows just how well preserved some of these finds are.
41
After tens of thousands of years, the meat is still sort of edible.
42
You can see their adorable fluffy little feet.
43
There's milk in the stomachs of some of these calves.
44
There's traces of blood.
45
Is this how they're going to de-extinct it?
46
Because they've got all of these good cells to work with.
47
Yeah, I mean the DNA is still there.
48
So much is so well preserved.
49
And that's all thanks to this incredible storage device that we call the permafrost.
50
Isn't permafrost just mud that's been frozen forever?
51
Yeah, it can be soil that's been frozen for a few years, up to 700,000 years.
52
It can be shallow or deep, and it covers this huge swath of the northern hemisphere.
53
Below it is actually unfrozen ground, so as you go deep enough, the heat of the earth is actually keeping things thawed out.
54
Oh, it's like a sandwich.
55
It's an ice cream sandwich.
56
And the top layer, which is freezing and thawing with the seasons, is called the active layer.
57
It can have forests and wetlands, and it was once home to mammoths and rhinos and prehistoric humans.
58
For thousands of years, a lot of those creatures somehow ended up getting stuck in the permafrost.
59
And they stayed there until...
60
Oooh.
61
It looks like something flesh-eating.
62
But this, I assume, is the top layer sort of caving in as the bottom layer also melts?
63
Yeah, this is caused by thawing permafrost.
64
I found this old, declassified spy run over Siberia from the 60s, and this chasm didn't even exist then.
65
But then it thawed and eroded over a few decades.
66
Wow, it's like a pretty clean cut.
67
It kind of just went straight down.
68
This leading edge, this little cliff, is still permafrost.
69
As this thing collapses, they found all kinds of animals.
70
They found mammoths, they found an ancient baby horse.
71
And so, if you're approaching this question, are microbes preserved in the permafrost?
72
Your hypothesis going in has got to be, of course, because it's preserving all these other things.
73
And sure enough, back in 1908, when a Russian scientist took that famous trunk, extracted a little bit of mammoth snot, and looked at it under the microscope,
74
he found the bodies of bacteria.
75
There was also bacteria in samples from the soil around that mammoth.
76
Now there's a chance this was contamination because sterilization protocols weren't standardized back then.
77
But since then, there's been a ton of studies that have found the remains of bacteria and viruses in the permafrost. Were they alive?
78
Well, that's the next question.
79
That's step two of Adam's five steps for a successful pandemic.
80
I want to put that question aside for a second and talk about a more personal one.
81
How do you find a fulfilling career?
82
Today's sponsor is unlike anything we've ever had.
83
They're not trying to get you to buy anything.
84
They're a nonprofit that wants to help you have a positive impact on the world.
85
They're called 80,000 Hours, which is about the amount of time in the average career.
86
And their mission, their entire reason for existing, is to help you find a satisfying job that will tackle some of the biggest problems facing humanity.
87
I've been poking around on their website and it's a pretty incredible resource.
88
They've got a curated job board that's constantly updated.
89
They've got email templates for reaching out to people you actually want to work for.
90
They've got a whole career guide that goes so far beyond the trite advice like follow your passion.
91
And what I really like is that advice is based on over a decade of research.
92
So I really encourage you to go to 80,000hours.org slash Howtown, you can click the link in our description,
93
to get their free career guide and start making a plan for your high-impact life.
94
Okay, now back to our pressing question.
95
Can the microbes that are preserved in the permafrost be brought back to life?
96
That is the same question this Russian scientist had.
97
He immediately took his snot sample, put it in a Petri dish, and bacteria grew.
98
Assuming there wasn't contamination, he showed that that bacteria came back to life and started growing.
99
Yeah, which is a pretty big assumption, but luckily there are more recent examples.
100
In 2015, scientists found a puppy buried in the permafrost.
101
It was about 14,000 years old and had a little bit of woolly rhino in its stomach.
102
When you said puppy, I thought it was going to be cute.
103
It's not cute.
104
No, it's pretty much a dirt clod, though it got slightly cuter once it got cleaned up.
105
Was there something growing inside of this creature?
106
Yes, they were able to extract and grow an ancient strain of a bacteria called Clostridium perfringens.
107
The next year, 2,000 reindeer in northwest Siberia came down with anthrax.
108
Anthrax is caused by bacteria, and they think that this came from a reindeer carcass that had sort of emerged from the permafrost.
109
One thing about both of these bacteria is that they're both able to form spores.
110
If the environmental conditions aren't ideal, they can create these little dehydrated, almost seeds with a tougher shell, and that helps them survive.
111
And that's like the the Mike and Ike shape?
112
Yes, exactly.
113
So we've got a couple of these spore formers that have come back to life, but there have been other types too, mostly sycrophiles.
114
Those are mostly non-threatening species that have adapted to cold soils.
115
So there have been a bunch of zombie bacteria.
116
But what about zombie viruses?
117
To answer that question, we have to take a little detour to Bradford, England in 1992, where scientists discovered something they couldn't explain.
118
They were looking for pathogens in a water sample when they came across these mysterious blobs.
119
And at first they said, these are so big, they've got to be bacteria.
120
Maybe this is a good time to do a little 101 on viruses and bacteria.
121
Yeah, meet the microbes.
122
Bacteria are these little, mostly single-celled organisms, but they're fairly complex.
123
A typical species has thousands of genes.
124
For comparison, here's a human cell, which has tens of thousands of genes.
125
Viruses are usually tiny, almost like simple machines.
126
Some have a couple hundred genes, but many have less than a dozen.
127
And viruses are, like, alive, not alive?
128
Is there a debate, or they're definitely not alive?
129
Well, they're in this gray area in that they can't replicate alone.
130
They have to sneak into cells of other species and trick their machinery into making more viruses.
131
One of the ways that you find viruses is you can put them through a really fine filter.
132
And basically, they're so small, they're the only things that make it through.
133
But those blobs from Bradford didn't make it through the filter.
134
And so the investigator thought, this is probably some weird little bacteria.
135
But he was very smart because he didn't throw away the sample.
136
He keep it in his fridge for more than 10 years.
137
And then he sent it to Jean-Michel.
138
My name is Jean-Michel John Michael Claverie from France.
139
That's why I have that strange accent.
140
I'm sorry about it.
141
We discovered that in fact this bacteria was a virus.
142
They called it the microbe mimicking virus or mimi virus.
143
The genome of that thing was also very big.
144
It had about a thousand genes.
145
So very weird.
146
Never been seen before.
147
I reorganized my laboratory totally at the time, looking everywhere to find out if we could find other viruses like that.
148
The next one they found, they called the mama virus because it was slightly bigger.
149
Cute.
150
They found a megavirus, Pandora virus, and then Pac-Man virus, Lost City.
151
That's its scientific name.
152
Oh, I see it.
153
But why Lost City?
154
Well, it came from a hydrothermal vent that's called the Lost City.
155
Okay.
156
So all of these giant viruses that they found attack amoeba.
157
So these scientists basically, they take the samples, they culture the sample with this amoeba, and they see what viruses grow.
158
One day I saw a paper by a Russian team.
159
This group in Russia found some seeds in an ancient Arctic ground squirrel burrow frozen in the permafrost.
160
and they were able to take that tissue and coax out these plants.
161
That's amazing.
162
And when I saw that paper, I said, well, if they can revive a plant, we should be able to revive viruses that are at least as old.
163
So they asked for a sample from this burrow, cultured it with an amoeba, and they got Pythovirus cybericum,
164
this giant virus bigger than anything they've ever seen.
165
And was this the first virus that was found in permafrost?
166
This is the first one that was resurrected.
167
Now they've found 15 of these giant viruses brought back from ancient times.
168
The oldest virus we were able to revive is 50,000 years old.
169
And what is the significance of them being giant?
170
Are they more hardy?
171
Well, this is one of the things.
172
Some of the extra genes these giant viruses have code for proteins that make really thick outer layers.
173
And maybe that's part of what's helping them survive.
174
Well, so far, you haven't convinced me not to worry about this.
175
Okay, yeah, well, we're only on step two, right?
176
It seems pretty easy for them to find some viruses and bring them back to life.
177
One big caveat to this, life outside the permafrost is pretty hard for a bacteria or a virus.
178
As soon as they get exposed to heat, to light, and to oxygen, they will start to degrade.
179
Some viruses are extremely fragile and will not survive more than a few minutes, up to a couple of hours.
180
And you need to be able to find a suitable host in that time.
181
The population of humans that lives on the permafrost is about 5 million.
182
So it's sort of like the size of your hometown, Phoenix, but spread over an area the size of North America.
183
So that lowers the odds that a microbe will encounter a human host.
184
But the worry is that that could change a little bit.
185
The Arctic has been warming about four times faster than the rest of the globe.
186
The real danger is that because of the global warming, It is now possible to have a lot of industrial development in the Arctic.
187
This is a giant open pit mine for diamonds.
188
They actually used jet engines to melt the permafrost to get through
189
that layer and down into the layer they wanted to mine.
190
These are multi-story buildings on this rim.
191
Wow.
192
You put 100,000 people in places where there was nobody there before.
193
All those little dots are just houses.
194
you're radically increasing the likelihood that you'll encounter some sort of virus or bacteria.
195
Yeah, they don't have to do much.
196
The people will come to them.
197
But it's not enough to just meet a human.
198
You have to be able to infect them.
199
And most bacteria in the permafrost can't infect us.
200
They just don't have the equipment to do so because they evolved to thrive in cold dirt.
201
And most viruses in the permafrost evolved to attack those bacteria, or in the case of the giant viruses, amoeba.
202
And that means they probably can't infect humans either.
203
Amoeba are extremely distant from us.
204
We diverged about 1 billion years ago from them.
205
And we only diverged from cats and dogs around 90 million years ago.
206
When your cat or if your dog got sick, you usually don't get the disease of your dog or your cat.
207
The chance that any virus capable of infecting an amoeba would be able to infect a human is extremely unlikely.
208
And the viruses that do infect people don't have those thick, tough shells.
209
Viruses that infect nice, warm-blooded hosts, they don't have any protective mechanisms.
210
Smallpox actually is a great test case because the smallpox virus is known for being extremely hardy.
211
They used to preserve smallpox scabs and use those to inoculate people with them
212
and they They would survive for a long time.
213
Right, right.
214
This is the original vaccine, right?
215
Yeah.
216
In 2004, researchers found the bodies of five 18th century smallpox victims buried deep in the permafrost.
217
The first question, of course, that people had was if there was any evidence of live virus.
218
And instead of trying to grow the virus, because that's dangerous for all sorts of reasons, what they used is DNA.
219
If they found big, long pieces of virus DNA, that would be evidence that viable virus, would still be there.
220
They were only able to find small, degraded viral bits, a few hundred A's, T's, C's and G's, which is really, really small.
221
People also tried to do this with the 1918 influenza virus.
222
There was an Alaskan village.
223
The pandemic raged through, killed 72 out of the 80 people in the village over the course of five days.
224
Wow.
225
They had gold miners come and bury the bodies deep into the permafrost.
226
Decades later, this scientist who was trying to understand the flu pandemic.
227
He got permission from the village elders and retrieved tissue that was really well intact.
228
Wasn't able to get any virus from them, though.
229
They tried for decades.
230
Eventually, with modern techniques, they were able to see that there were some scraps.
231
Very small RNA fragments.
232
No live virus at all.
233
This is kind of the ideal scenario.
234
If you're one of these viruses, you want to be frozen immediately after your host dies.
235
You're immediately put in this super protective place.
236
And then they only had to travel, in one case a few centuries, but in another case just decades into the future.
237
And even under those ideal conditions, they didn't survive.
238
And does the size of the flu virus and the smallpox, is the small size probably the reason why they didn't come back to life?
239
If you don't have very many genes and you don't have very many proteins to work with, you've just got like the basic, you know, the basic shell.
240
And that just isn't cutting it, it seems like, to keep you protected and make you survive.
241
When it comes to bacteria, we have seen some that could potentially infect people.
242
There was that anthrax outbreak in the reindeer, and some infected reindeer meat ended up sickening some people and even killing one boy.
243
And in the case of that ancient puppy bacteria, that species can cause gas gangrene, though there's never been a case that was linked back to the permafrost.
244
And we've never seen any evidence that the bacteria that cause big pandemics, the plague, tuberculosis, cholera, those bacteria that thrive in our warm,
245
wet bodies, there's no evidence that they could survive in the frozen permafrost.
246
In short, it's pretty hard for a human pathogen to even make it as far as step four.
247
The only time we think that happened was that one anthrax outbreak.
248
But even that wasn't enough to achieve a pandemic.
249
A pandemic requires not just that one person gets infected from the environment, but that that turns into transmission throughout an entire population.
250
So let's review our cast of microbes and see how many of the five steps each of them completed.
251
Some bacteria, like the one that causes plague, likely wouldn't survive past step two.
252
Most of the bacteria that do make it out of the permafrost don't infect humans, and the ones that can, like anthrax and clostridium, those aren't bacteria that you see being transmitted from person to person.
253
That's just not how those particular bacteria work.
254
The giant viruses from the permafrost don't infect humans, and we've seen that the smallpox and flu bugs were ripped to shreds before they could get that far.
255
To make it further, any pathogen would also have to contend with the human technologies that can slow or stop transmission.
256
Most antibiotics target these very foundational processes within bacteria that are conserved across the entire kingdom.
257
Antibiotics probably are going to be able to get rid of those old bacteria.
258
The same for viruses that we know about.
259
If smallpox come back, yes, there will be a couple of problems, but we have a vaccine for the smallpox.
260
So the big fear is of some unknown virus
261
that somehow is able to make it through every single one of these steps and then become transmissible.
262
Right, because it only takes one.
263
Every single virus is different from the next one.
264
So any single new virus poses its own problem.
265
And that's why I'm more worried about viruses.
266
And I'm more worried about viruses that we know nothing about, which are the old ones.
267
It would take us a while to develop a vaccine that would be for that specific virus, probably.
268
This is a real risk, but it's not any higher than the risk of some mysterious virus emerging from any ecosystem.
269
It can't be completely discounted, but it's not something that's high on my concern list.
270
There's unknown viruses in the ocean.
271
There's unknown viruses in every corner of the world.
272
And those corners of the world have a lot more living stuff in them.
273
And they're changing all the time.
274
And they're changing all the time.
275
They're evolving.
276
The permafrost is sort of like an archive of past pathogens, but the world is a living zoo of pathogens.
277
I think that the risk from thawing permafrost is about the same as from regular soils.
278
And if you look back to the history in the Arctic, for thousands and thousands of years, people have been using permafrost as food storage.
279
People have been exposed to permafrost microorganisms for millennia.
280
That's very comforting in a way.
281
The bad news is that if you are worried about diseases and climate change,
282
there's plenty to worry about because of warm weather microbes thriving and increasing their range as the temperatures increase, right?
283
Yeah, I think that it probably couldn't hurt to like monitor the Arctic to try
284
and make sure that we catch anything that comes out of it.
285
But I'm much more worried about what you just talked about.
286
Even within the existing range of an infectious disease, you know, something like warming temperatures can increase the time of the year when it can affect people.
287
And we're talking a lot of times about diseases that we already know how to prevent, but we don't for the poorest people in the world, the people who also happen to be the least responsible for global warming.
288
Even though I'm not going to lose any sleep over a permafrost pandemic, there's still plenty to worry about.
289
But I think the thing
290
that maybe you should think about as you're falling asleep instead is just how cool these giant viruses are
291
and how much they like this whole other world of what
292
it means to be a sort of living thing in the world that we don't really know much about.
293
I mean, these viruses have hundreds, sometimes thousands of genes.
294
That's a whole library of proteins that we don't didn't know about before
295
that maybe could be useful to us or maybe could tell us something more about how life evolved.
296
Well, I feel comforted because I do feel like there's a tendency to feel widespread doom about everything related to environmental change.
297
It just takes a little bit of effort, as you've shown, to really parse through what to worry about, what not to worry about, where to focus, the resources.
298
Sorry, there's a siren.
299
As the sirens start.
300
There's plenty to worry about in the world besides this.
301
There's plenty to worry about.
302
Zombie virus is like such a cool headline though.
303
If you'd like to see us make more independent science journalism, there's a few free things you can do to help us out.
304
One is of course subscribe, another is sign up for a free monthly newsletter on Patreon,
305
and the last is to visit 80,000 hours.org slash Howtown to get their free career guide.
📺 Same Channel
✨ Recommend Video
B23
155 sentences
Why Ancient Humans Were The Most TERRIFYING Animal Alive
IELTS PrepTOEFL Prep+2
B221
46 sentences
Reading Unit 10A
IELTS PrepTOEFL Prep+2
B22
222 sentences
The Mutated Animals of Chernobyl
IELTS PrepTOEFL Prep+2
B2100
14 sentences
Scientists Solve the Mystery Behind the Oumuamua 'Alien Spacecraft' Comet
IELTS PrepTOEFL Prep+2
B21
62 sentences
IELTS listening actual test Part 4: The preservation of fossils (answer+ transcript)
IELTS PrepTOEFL Prep+2
C1285 sentences
When Antarctica Was a Jungle
IELTS PrepTOEFL Prep+2
B21
211 sentences
The Biggest Problem No One Is Talking About
IELTS PrepTOEFL Prep+2
B25
45 sentences
RE3 Unit 3B
IELTS PrepTOEFL Prep+2
B22
120 sentences
What’s Ruining Our Ruins?
American Accent, en-USIELTS Prep+3
C14
34 sentences
Genetic Engineering and Diseases – Gene Drive & Malaria
IELTS PrepTOEFL Prep+2
C13
37 sentences
The Megatsunami That Struck the Entire Planet
IELTS PrepTOEFL Prep+2
B2291 sentences
Why did white men conquer the world?
IELTS PrepTOEFL Prep+2
About This Lesson
You're practicing English with "When Siberia thaws, what emerges?" using the Shadowing technique — a method originally developed for professional interpreter training.
Focus on sounding like the speaker — not just repeating words. With 15–30 minutes of daily practice, you'll build real-world speaking confidence.
What is the Shadowing Technique?
Shadowing is a science-backed language learning technique originally developed for professional interpreter training and popularized by polyglot Dr. Alexander Arguelles. The method is simple but powerful: you listen to native English audio and immediately repeat it out loud — like a shadow following the speaker with just a 1–2 second delay. Unlike passive listening or grammar drills, shadowing forces your brain and mouth muscles to simultaneously process and reproduce real speech patterns. Research shows it significantly improves pronunciation accuracy, intonation, rhythm, connected speech, listening comprehension, and speaking fluency — making it one of the most effective methods for IELTS Speaking preparation and real-world English communication.