B1 中级 English 8:41 1,329 单词 Science & Tech

This Island Might Help Us Understand The Origins of Life

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Learning Stats

B1

CEFR 等级

1,329

Total Words

614

Unique Words

5/10

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Vocabulary Diversity 46%

字幕 (125 segments)

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00:00

Early in the morning on November 14th, 1963,  sailors on a fishing boat off Iceland's southern  

00:06

coast were enjoying a cup of hot coffee when  they caught a whiff of something weird.

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Sulfur.

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They couldn't figure out where  the smell was coming from.

00:15

The cook wasn't making eggs.

00:17

The ship's motor wasn't malfunctioning.

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And Magnus hadn’t eaten beans that night.

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It wasn't until dawn broke when  they saw the source of the smell.

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Off in the distance, an ominous column  of smoke billowed from the seasurface.

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Turns out, it wasn't really smoke,  but a volcanic plume of ash and  

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gas—including sulfur—that emanated from  a volcano erupting on the seafloor.

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It took less than a day for the puffs of sulfurous  smoke to rapidly grow 10 meters above the water,  

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creating the brand new island that the  Iceland Naming Committee called Surtsey.

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While it didn’t look like much then, that island  has turned out to be a Godsend for scientists.

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It has given them a rare opportunity to study  

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everything from how ecosystems evolve  on new land to the origins of life.

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And they're still learning  new things about it today.

01:11

[♪ INTRO]

01:14

For starters, a volcanic eruption off the  coast of Iceland isn’t exactly shocking,  

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because the whole country sits along a  feature called the mid-Atlantic ridge.

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This is where tectonic plates  pull apart from one another,  

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causing hot rocks to rush upward,  and sparking volcanic eruptions.

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When hot lava meets water,  the results are explosive.

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Water flashes to steam and  blasts apart the volcanic rock,  

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and the eruption itself flings  out material called tephra.

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The smallest bits of tephra are volcanic ash,  

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and the largest chunks are  called volcanic blocks or bombs.

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When Iceland's submarine volcano erupted,  

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tephra and lava rock quickly piled up on the  seafloor, about 130 meters below the surface.

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The debris built up rapidly  and created the island Surtsey.

02:03

And this type of explosive volcanic  

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eruption under shallow water is called a  surtseyan eruption after, well, Surtsey.

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The geologic infant grew to a stunning 174  meters above sea level in just three months!

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Like moths to a flame, scientists  flocked to Surtsey to study this  

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new land, for a very specific reason.

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Lava is so hot that when it first  cools to stone, it's sterile.

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So islands like Surtsey are a  rare chance to understand how  

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waves of critters inhabit new land and how  ecosystems evolve in harsh remote areas.

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This made Surtsey a kind of giant terrarium  for watching an ecosystem develop in real time.

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And it all starts with the first  arrivals, called pioneer species.

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For lava flows on land, the first living  things to appear are often lichens and mosses,  

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which can attach to bare rock  and don't need soil to thrive.

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But Surtsey dared to be different.

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Instead of the flat, sometimes frilly, lichens,  

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one of the island's earliest pioneers  was a flowering plant called a searocket.

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It washed onto the shores in the  Spring after the island's birth,  

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before the volcano had even stopped erupting.

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While slightly late to the party, mosses  and lichens took hold a few years later,  

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their spores likely lofted by winds to the island.

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They mostly grew on steep lava rocks where steam  from the crater was keeping the walls moist.

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One reason mosses and lichens were such late pioneers was  

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because shifting beaches of volcanic  tephra made up much of the island.

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And many areas that were solid rock still rapidly  changed as waves battered the freshly cooled lava.

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While beachfront property is scenic, it's tough  to build a home on a crumbling foundation!

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In fact, some parts of Surtsey weren't  

03:52

stable enough for lichens to  colonize until decades later.

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Winds also carried larger life,  like grasses and small willows.

04:00

But despite these leafy pioneers,  Surtsey remained largely animal-free  

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until the first arrivals came  down from the skies - birds!

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Gulls established colonies in 1985,  which rapidly transformed the landscape.

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They brought seeds and vegetation from  nearby islands and, most importantly,  

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they did what birds do best.

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They pooped everywhere.

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Their droppings fertilized the land helping create  

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nutrient-rich soil in which  other plants can take root.

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The earliest avian residents  relied on the sea for food.

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And their activity on the island, from  eating to pooping and everything else,  

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all helped the development of soils on the island.

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That’s harder than it sounds, because  soil is kind of a living thing,  

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chock full microorganisms of all kingdoms.

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Soil allowed insect life to settle in, and from  there, ecosystem evolution was off to the races.

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All that makes it sound like Surtsey is a  great place to take a nature-focused vacation.

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Sadly, that’s not in the cards for the vast  majority of people, as Surtsey was declared  

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a nature reserve in 1965, prohibiting tourist  traffic in order to preserve this ecosystem.

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Scientists have done all they could to  protect the land from human invaders.

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But they’ve had a few unintentional impacts.

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In the summer of 1969, scientists  stumbled across a surprisingly familiar plant,  

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one you might even have in  your backyard: a tomato!

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What was this heat-loving crop  doing on Surtsey's chilly shores?

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Specialist Ágúst Bjarnason was  called in to find the answer.

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He cleared the rocks covering the plant's base  to reveal what he called a "peculiar pile."

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He poked at it and then it dawned on him:  

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Some person must have eaten a tomato and  then done their business on the island's  

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shores without properly removing the waste,  which gave life to this leafy intruder.

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The scientists swiftly removed the  plant, but its appearance was a  

06:01

lesson in how much impact we can have on  the land, even when we're not trying to.

06:07

But before we drop more peculiar  piles of information on this island,  

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all science needs funding, and so do we.

06:14

So here’s a quick ad.

06:16

Thanks for watching this SciShow video!

06:18

When you and your friends watch our shows,  

06:19

it helps us continue to make free  educational stuff that you love.

06:23

But that’s not the only way to  show your support for SciShow.

06:25

We have a whole merch store, too!

06:27

At Complexly.store, you can get SciShow  T-shirts through the end of the year,  

06:30

plus stickers, mugs, and  coloring books until we run out.

06:34

They make great gifts for the  lifelong learner on your list.

06:36

Just be sure to order your T-shirts before  November 21 if you’re outside the US and  

06:41

before December 8 within the US if  you want to gift them for Christmas.

06:44

Thanks for your support!

06:45

We couldn’t do all of this without you.

06:47

Apart from learning the importance of  proper waste management, the island of  

06:51

Surtsey also gave scientists a model for  understanding the origins of life itself.

06:57

The earliest glimmers of life on  Earth probably appeared when land  

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around the world looked a lot like  Surtsey: burbling volcanic islands  

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poking up as isolated landmasses in a  vast ocean that blanketed the world.

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By studying the volcanic gasses and  compounds belched up during the eruption,  

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researchers gathered clues about the possible  ingredients of our planet's primordial soup.

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The eruption also hinted at what energy  source drove those first sparks of life— 

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volcanic lightning, which dramatically  filled the skies during Surtsey's eruption.

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Lightning drives chemical reactions,  

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perhaps concentrating important compounds,  including the raw materials for life.

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While studying Surtsey's early chemistry,  scientists were excited to find traces  

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of amino acids, the building blocks of  proteins, which are the basis for life.

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But there's no way to tell whether  the amino acids formed abiotically,  

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or without help from microbes, as would  have been the case on infant Earth.

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There's still a lot to learn from  Surtsey, which is why scientists  

07:59

return to the island each year to continue  studying the evolution of life there.

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But Surtsey's time is running out.

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While scientists estimate it'll remain  above the seasurface for centuries,  

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the island is now shrinking.

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However, it's only a matter of time  before Earth belches up another island,  

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and another remarkable opportunity for scientists  to study the development of life in action.

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But hopefully next time, the researchers won’t  poop out any plant seeds when they get there.

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[♪ OUTRO]

Key Vocabulary (50)

to A1 preposition

toward

"Go to school."

of A1 preposition

belonging

"Cup of tea."

and A1 conjunction

also

"You and me."

in A1 preposition

inside

"In the house."

that A1 determiner

specific

"That book."

it A1 pronoun

A third-person singular pronoun used to refer to an object, animal, or situation that has already been mentioned or is clear from context. It is also frequently used as a dummy subject to talk about time, weather, or distance.

for A1 preposition

Used to show who is intended to have or use something, or to explain the purpose or reason for an action. It is also frequently used to indicate a specific duration of time.

on A1 preposition

A preposition used to indicate that something is in a position above and supported by a surface. It is also used to indicate a specific day or date, or to show that a device is functioning.

you A1 pronoun

Used to refer to the person or people that the speaker is addressing. It is the second-person pronoun used for both singular and plural subjects and objects.

this A1 pronoun

Used to identify a specific person, thing, or idea that is physically close to the speaker or has just been mentioned. It can also refer to the present time or a situation that is currently happening.

but A1 conjunction

A coordinating conjunction used to connect two statements that contrast with each other. It is used to introduce an added statement that is different from what has already been mentioned.

from A1 preposition

Used to indicate the starting point, source, or origin of something. It can describe a physical location, a point in time, or the person who sent or gave an item.

they A1 pronoun

A third-person plural pronoun used to refer to two or more people, animals, or things previously mentioned. It is also commonly used as a singular pronoun to refer to a person whose gender is unknown or to someone who identifies as non-binary.

we A1 pronoun

The word 'we' is a first-person plural pronoun used to refer to the speaker and one or more other people collectively. It is used as the subject of a sentence or clause.

all A1 determiner

Used to refer to the whole quantity or amount of something, or to every member of a group. It indicates that nothing has been left out from the total being discussed.

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Go to https://Complexly.store to support Complexly this holiday season! The island of Surtsey off the coast of Iceland popped up basically in a week, and it's been a perfect natural experiment...

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