The mysterious microbes living deep inside the earth -- and how they could help humanity | K. Lloyd

翻译人员: Jingdan Niu 校对人员: Cissy Yun

It may seem like we're all standing on solid earth right now,

看起来我们现在都站在 坚固的地球表面上，

but we're not.

然而并不是。

The rocks and the dirt underneath us are crisscrossed by tiny little fractures

在我们脚下的石头和尘土里 交叉分布着

and empty spaces.

细小的断裂层和空隙。

And these empty spaces are filled with astronomical quantities of microbes,

这些空隙中充满 天文数量级的微生物，

such as these ones.

比如这些。

The deepest that we found microbes so far into the earth

目前我们可以找到微生物的最大深度

is five kilometers down.

是地下5000米。

So like, if you pointed yourself at the ground

所以，如果你在地面上定一个点位，

and took off running into the ground,

然后开始向地心跑，

you could run an entire 5K race and microbes would line your whole path.

沿途5000米的路径上都能看到微生物。

So you may not have ever thought about these microbes

所以你可能从来没想到这些微生物

that are deep inside earth's crust,

还存在于地壳的深处，

but you probably thought about the microbes living in our guts.

但是你可能会想到生活 在我们内脏里的微生物。

If you add up the gut microbiomes

如果你将地球上所有生物的

of all the people and all the animals on the planet,

内脏微生物全部加在一起，

collectively, this weighs about 100,000 tons.

它们的重量约有10万吨。

This is a huge biome that we carry in our bellies every single day.

每一天，这么庞大的生物群 就生活在我们的肚子里。

We should all be proud.

我们都应该感到非常骄傲。

(Laughter)

（笑声）

But it pales in comparison to the number of microbes

但是相对于可以覆盖 整个地球表面的微生物，

that are covering the entire surface of the earth,

比如在土壤里、河里和海里的微生物，

like in our soils, our rivers and our oceans.

内脏里的微生物 就显得相形见绌了。

Collectively, these weigh about two billion tons.

它们加起来约有20亿吨。

But it turns out that the majority of microbes on earth

但是事实说明大部分地球上的微生物

aren't even in oceans or our guts or sewage treatment plants.

并不是在我们的内脏或者污水处理厂里。

Most of them are actually inside the earth's crust.

实际上，它们大多数都在地壳里。

So collectively, these weigh 40 billion tons.

所以这些加起来有400亿吨重。

This is one of the biggest biomes on the planet,

这是地球上最大的微生物群之一，

and we didn't even know it existed until a few decades ago.

而我们在几十年前才发现它们的存在。

So the possibilities for what life is like down there,

所以地球下的生活是什么样，

or what it might do for humans,

或者它们对人类的影响

are limitless.

无法估量。

This is a map showing a red dot

这个地图上的红点标记的每一个地方

for every place where we've gotten pretty good deep subsurface samples

都是我们通过现代微生物学手段

with modern microbiological methods,

获得的非常好的地表下层样本。

and you may be impressed

你可能想不到，

that we're getting a pretty good global coverage,

我们在全球各地都有取样。

but actually, if you remember that these are the only places

但是实际上，如果你发现 这些是我们仅有的几个采样地点，

that we have samples from, it looks a little worse.

情况看起来就没那么乐观了。

If we were all in an alien spaceship,

假如我们在一个外星人的飞船上，

trying to reconstruct a map of the globe from only these samples,

试图通过仅有的这些样本 来重新构建地球的地图，

那是绝对不可能做到的。

we'd never be able to do it.

So people sometimes say to me,

有时候有人跟我说，

"Yeah, there's a lot of microbes in the subsurface, but ...

“没错，地表下有很多微生物，但是……

aren't they just kind of dormant?"

它们不是在冬眠吗？”

This is a good point.

这是非常好的一个问题。

Relative to a ficus plant or the measles or my kid's guinea pigs,

当比无花果属植物或者麻疹， 或者是我小孩养的那些豚鼠，

these microbes probably aren't doing much of anything at all.

这些微生物大概真的是什么事情都不做。

We know that they have to be slow, because there's so many of them.

我们知道因为它们数量过于庞大， 它们不得不成长得很缓慢。

If they all started dividing at the rate of E. coli,

如果它们按照大肠杆菌的速度开始分裂，

then they would double the entire weight of the earth, rocks included,

仅仅一夜之间， 它们就让整个地球，包括石头的

over a single night.

重量翻倍。

In fact, many of them probably haven't even undergone a single cell division

实际上，从古埃及时代以后，

since the time of ancient Egypt.

很多微生物大概甚至没有 完成过一次细胞分裂。

Which is just crazy.

这真是太神奇了。

Like, how do you wrap your head around things that are so long-lived?

我们到底该如何去看待 这样长寿的东西？

But I thought of an analogy that I really love,

但是我想到了一个我非常喜欢的类比，

but it's weird and it's complicated.

虽然它听起来会有些奇怪和复杂。

So I hope that you can all go there with me.

我希望你们可以听听看。

Alright, let's try it.

好的，让我们试试。

It's like trying to figure out the life cycle of a tree ...

这个类比就像是试图理解 一棵树的生命周期……

if you only lived for a day.

如果你只能活一天。

So like if human life span was only a day, and we lived in winter,

所以假如人类的生命只有一天， 并且是在冬天 ，

then you would go your entire life

那么你的整个人生，

without ever seeing a tree with a leaf on it.

都不会在树上看到任何一片叶子。

And there would be so many human generations

在仅仅一个冬天里，

that would pass by within a single winter

人类就会拥有非常多的后代子孙，

that you may not even have access to a history book

以致于历史书上

that says anything other than the fact that trees are always lifeless sticks

只会记载树木 是一个没有生命的棍子，

that don't do anything.

没啥用处。

Of course, this is ridiculous.

当然，这种结论很荒唐。

We know that trees are just waiting for summer

我们知道树木 只是在等待夏天的到来，

so they can reactivate.

这样它们就可以恢复活力。

But if the human life span

但是假如人类的寿命

were significantly shorter than that of trees,

明显比树木的寿命短，

we might be completely oblivious to this totally mundane fact.

我们可能就完全不会察觉到 这个非常平凡的事实。

So when we say that these deep subsurface microbes are just dormant,

所以当我们说这些深埋于 地下的微生物只是在沉睡，

are we like people who die after a day, trying to figure out how trees work?

我们是不是就像那些寿命只有一天 却试图理解树木如何生存的人们？

What if these deep subsurface organisms

这些地表下的微生物

are just waiting for their version of summer,

会不会只是在等待它们的“夏天”，

but our lives are too short for us to see it?

而我们只是因为生命太短暂而无法看到？

If you take E. coli and seal it up in a test tube,

如果你将大肠杆菌封闭在一个试管里，

with no food or nutrients,

没有食物或者营养剂给它，

and leave it there for months to years,

然后将它成年累月的放在那里不管，

most of the cells die off, of course, because they're starving.

当然，大部分细胞都会饿死。

But a few of the cells survive.

但是很小一部分细胞会生存下来。

If you take these old surviving cells

如果你取下这些年老的 存活下来的细胞，

and compete them, also under starvation conditions,

让它们在饥饿的条件下，

against a new, fast-growing culture of E. coli,

和一些新的、快速成长的 大肠杆菌竞争，

the grizzled old tough guys beat out the squeaky clean upstarts

这些头发花白、吃苦耐劳的老年人 每一次都打败了吱吱作响的

every single time.

干净的新贵。

So this is evidence there's actually an evolutionary payoff

所以，这证明了 进化的格外缓慢

to being extraordinarily slow.

其实有好处。

So it's possible

所以有可能，

that maybe we should not equate being slow with being unimportant.

我们也许不应该将慢等同于不重要。

Maybe these out-of-sight, out-of-mind microbes

也许这些看不见的， 我们不放在心上的微生物

could actually be helpful to humanity.

实际上对人类是有帮助的。

OK, so as far as we know,

目前我们所知道的是，

there are two ways to do subsurface living.

有两种方法让它们在地表下的生活。

The first is to wait for food to trickle down from the surface world,

第一种是等待食物从地表向下滴流，

like trying to eat the leftovers of a picnic that happened 1,000 years ago.

这就好像尝试吃从一千年前的 野餐上剩下来的食物。

Which is a crazy way to live,

真是个疯狂的生活方式。

but shockingly seems to work out for a lot of microbes in earth.

令人吃惊的是，对于很多地球上的 微生物来说，这个方法是可行的。

The other possibility is for a microbe to just say,

另外一种方式是， 微生物会觉得，

"Nah, I don't need the surface world.

“我不需要地表世界，

I'm good down here."

我在这下面挺好的。”

For microbes that go this route,

对于选择这条路的微生物来说，

they have to get everything that they need in order to survive

它们为了生存，不得不从地球内部

from inside the earth.

来获取它们所需求的一切。

Some things are actually easier for them to get.

实际上，有些东西 对它们来说比较容易获得。

They're more abundant inside the earth,

这些东西在地球里面更加充足，

like water or nutrients, like nitrogen and iron and phosphorus,

比如水源或者营养， 比如氮、铁和磷，

or places to live.

或者可以居住的地方。

These are things that we literally kill each other to get ahold of

这些是我们在地表世界上 需要靠互相厮杀

up at the surface world.

来得到的东西。

但是在地表下，它们只需要担心 是否有足够的能量。

But in the subsurface, the problem is finding enough energy.

Up at the surface,

在地表上，

plants can chemically knit together carbon dioxide molecules into yummy sugars

当太阳光子照到植物的叶子上时，

as fast as the sun's photons hit their leaves.

它们可以尽快地 将二氧化碳分子转化成美味的糖分。

But in the subsurface, of course, there's no sunlight,

但是在地表下，当然了， 那里没有阳光，

so this ecosystem has to solve the problem

所以这个生态系统 不得不解决这个问题：

of who is going to make the food for everybody else.

谁来给其它的微生物制造食物。

The subsurface needs something that's like a plant

地表下需要像植物那样的东西，

but it breathes rocks.

但是呼吸的是石头。

Luckily, such a thing exists,

幸运的是，存在这么一个东西，

and it's called a chemolithoautotroph.

叫做化能无机自养生物。

(Laughter)

（笑声）

Which is a microbe that uses chemicals -- "chemo,"

这个单词是由一个微生物 利用化学物质——“chemo”

from rocks -- "litho,"

从石头里——"litho"，

to make food -- "autotroph."

生产食物——"autotroph"。

And they can do this with a ton of different elements.

它们可以用大量不同的元素。

They can do this with sulphur, iron, manganese, nitrogen, carbon,

它们可以用硫磺、铁、镁、氮、碳，

some of them can use pure electrons, straight up.

其中有些可以直接用纯电子。

Like, if you cut the end off of an electrical cord,

就像是，如果你切掉 一个电线的尾部，

they could breathe it like a snorkel.

它们可以用它呼吸， 就像潜水通气管那样。

(Laughter)

（笑声）

These chemolithoautotrophs

这些化能无机自养生物

take the energy that they get from these processes

将这个过程中得到的能量

and use it to make food, like plants do.

用来制造食物，就像植物那样。

But we know that plants do more than just make food.

但是我们知道植物 并不仅仅只是制造食物。

They also make a waste product, oxygen,

它们也可以制造 一种多余的产物，氧气，

which we are 100 percent dependent upon.

这是我们百分之百赖以生存的东西。

But the waste product that these chemolithoautotrophs make

但是这些化能无机自养生物 制造的多余的产物

is often in the form of minerals,

则是矿物，

like rust or pyrite, like fool's gold,

比如锈或者黄铁矿，包括愚人金，

or carminites, like limestone.

或者碳酸盐，包括石灰岩。

So what we have are microbes that are really, really slow, like rocks,

我们的微生物，就像石头那样， 变化非常非常慢，

that get their energy from rocks,

它们从石头里获取能量，

that make as their waste product other rocks.

来制造的多余的产物，还是石头。

So am I talking about biology, or am I talking about geology?

所以我是在讨论生物， 还是在讨论地理？

This stuff really blurs the lines.

这个东西真的很难定义。

(Laughter)

（笑声）

So if I'm going to do this thing,

如果我要研究微生物，

and I'm going to be a biologist who studies microbes

并且我将要作为一名生物学家

that kind of act like rocks,

来研究这种行为像石头一样的微生物，

then I should probably start studying geology.

那么，我大概应该开始学习地理了。

And what's the coolest part of geology?

那么，地理最酷的部分是什么呢？

Volcanoes.

火山。

(Laughter)

（笑声）

This is looking inside the crater of Poás Volcano in Costa Rica.

这是从哥斯达黎加的 珀阿斯火山口内部的景象。

Many volcanoes on earth arise because an oceanic tectonic plate

地球上许多火山 是由于海洋地壳构造板块

crashes into a continental plate.

撞上大陆板块而出现的。

As this oceanic plate subducts

当海洋板块下沉

or gets moved underneath this continental plate,

或移动到大陆板块下面时，

things like water and carbon dioxide and other materials

像水和二氧化碳以及其它的物质

get squeezed out of it,

就被挤压脱离了大陆板块，

like ringing a wet washcloth.

就像箍住了一块湿毛巾。

So in this way, subduction zones are like portals into the deep earth,

这样一来，俯冲带就成了 通往地壳的传送带，

where materials are exchanged between the surface and the subsurface world.

在这里，地表和地表下的物质 得以相互交换。

So I was recently invited by some of my colleagues in Costa Rica

最近我收受到一些 在哥斯达黎加的同事邀请，

to come and work with them on some of the volcanoes.

和他们一起对一些火山进行研究。

And of course I said yes, because, I mean, Costa Rica is beautiful,

当然，我同意了， 因为我觉得哥斯达黎加很漂亮，

but also because it sits on top of one of these subduction zones.

但是也是因为哥斯达黎加位于 这其中一个俯冲带的上方。

We wanted to ask the very specific question:

我们想问一个非常具体的问题：

Why is it that the carbon dioxide

为什么从这个深埋的海洋板块中

that comes out of this deeply buried oceanic tectonic plate

释放出来的二氧化碳

is only coming out of the volcanoes?

只能来自火山呢？

Why don't we see it distributed throughout the entire subduction zone?

为什么它没有分部在整个俯冲带？

Do the microbes have something to do with that?

这和微生物会不会有什么联系？

So this is a picture of me inside Poás Volcano,

这是我和我的同事 多纳托·吉欧瓦内利

along with my colleague Donato Giovannelli.

在珀阿斯火山里的一张照片。

That lake that we're standing next to is made of pure battery acid.

在我们旁边的是一个 由纯蓄电池酸液构成的湖泊，

I know this because we were measuring the pH when this picture was taken.

拍这张照片的时候 我们正在测试pH值。

And at some point while we were working inside the crater,

在某个时刻，

我转过身去对我哥斯达黎加的同事 卡洛斯·拉米雷斯说，

I turned to my Costa Rican colleague Carlos Ramírez and I said,

"Alright, if this thing starts erupting right now,

“如果这个东西现在开始喷发，

what's our exit strategy?"

我们有什么逃生策略吗？”

And he said, "Oh, yeah, great question, it's totally easy.

然后他说，“哦，当然了， 好问题，这非常简单，

Just turn around and enjoy the view."

转过身欣赏一下这个景象。”

(Laughter)

（笑声）

"Because it will be your last."

“因为这将是你最后看到的风景。”

(Laughter)

（笑声）

And it may sound like he was being overly dramatic,

这可能听起来是过于夸张了，

but 54 days after I was standing next to that lake,

但是在54天之后，

this happened.

这一幕发生了。

Audience: Oh!

观众：啊！

Freaking terrifying, right?

太吓人了，是吧？

(Laughs)

（笑声）

This was the biggest eruption this volcano had had in 60-some-odd years,

这是这个火山在60多年来 发生的最大的一次喷发，

and not long after this video ends,

并且在拍完这段视频之后，

the camera that was taking the video is obliterated

拍摄这个视频的摄像机就模糊了，

and the entire lake that we had been sampling

并且我们曾经取样的整个湖泊

vaporizes completely.

完全蒸发了。

But I also want to be clear

但是我也想申明，

that we were pretty sure this was not going to happen

在火山现场的那一天，

on the day that we were actually in the volcano,

我们是非常确定这种事是不会发生的，

因为哥斯达黎加通过 公立大学地震火山观测站

because Costa Rica monitors its volcanoes very carefully

through the OVSICORI Institute,

对火山进行了非常细致的观测，

and we had scientists from that institute with us on that day.

并且那一天也有研究所的 科学家与我们同行。

But the fact that it erupted illustrates perfectly

但是火山喷发完美的说明了

that if you want to look for where carbon dioxide gas

如果你想找二氧化碳

is coming out of this oceanic plate,

是从海洋板块的哪个位置产生的，

then you should look no further than the volcanoes themselves.

没有比观察火山本身更好的机会了。

But if you go to Costa Rica,

但是如果你去哥斯达黎加，

you may notice that in addition to these volcanoes

除了火山，你还应该注意到

there are tons of cozy little hot springs all over the place.

这里遍地都是舒适的温泉。

Some of the water in these hot springs is actually bubbling up

这些温泉里的一些水源实际上就是

from this deeply buried oceanic plate.

深埋于海洋板块之下的 气泡上升而成的。

And our hypothesis was that there should be carbon dioxide

而我们的假设就是二氧化碳应该

bubbling up with it,

会和气泡一起上升，

but something deep underground was filtering it out.

但是一些地下的东西将它过滤掉了。

So we spent two weeks driving all around Costa Rica,

所以我们用了两周的时间， 在哥斯达黎加

sampling every hot spring we could find --

将我们可以找到的 所有温泉都取样了——

it was awful, let me tell you.

大家都疲惫不堪。

And then we spent the next two years measuring and analyzing data.

然后我们花了接下来两年时间 测量和分析数据。

And if you're not a scientist, I'll just let you know that the big discoveries

如果你不是一个科学家， 我现在告诉你科研发现

don't really happen when you're at a beautiful hot spring

一般不会在一个漂亮的温泉里

或者公共演讲台上发生；

or on a public stage;

它们发生在你弓着腰 坐在一个凌乱的电脑前的时候，

they happen when you're hunched over a messy computer

or you're troubleshooting a difficult instrument,

或者你在排查一个 复杂仪器的故障的时候，

or you're Skyping your colleagues

或者你在和你的同事视频的时候，

because you are completely confused about your data.

因为你已经完全看不懂数据了。

Scientific discoveries, kind of like deep subsurface microbes,

科研发现就像是 深层地表下的微生物，

can be very, very slow.

这个过程是非常、非常慢的。

But in our case, this really paid off this one time.

但对我们来说， 花这些时间是值得的。

We discovered that literally tons of carbon dioxide

我们发现，表面上，大量的二氧化碳

were coming out of this deeply buried oceanic plate.

是来自于这个深埋的海洋板块。

And the thing that was keeping them underground

而让它们始终存在于地下

and keeping it from being released out into the atmosphere

并且让它们无法被释放到空气中的

was that deep underground,

则是这个深藏于地下的，

underneath all the adorable sloths and toucans of Costa Rica,

在哥斯达黎加所有可爱的树懒 和巨嘴鸟下面的，

were chemolithoautotrophs.

化能无机自养生物。

These microbes and the chemical processes that were happening around them

这些微生物和它们周围的化学过程

were converting this carbon dioxide into carbonate mineral

将二氧化碳转化成碳酸盐矿物，

and locking it up underground.

并且将它们留在在地表之下。

Which makes you wonder:

这会让你们感到奇怪：

If these subsurface processes are so good at sucking up

如果这些地表下的过程如此重要，

all the carbon dioxide coming from below them,

可以把地面下产生的 二氧化碳全部吸收，

could they also help us with a little carbon problem

那它们能不能针对我们地表上的

we've got going on up at the surface?

二氧化碳问题帮上一点忙？

Humans are releasing enough carbon dioxide into our atmosphere

我们知道，人类往空气中 释放了太多的二氧化碳，

that we are decreasing the ability of our planet

以致于减弱了我们的地球

to support life as we know it.

维护生命的能力。

And scientists and engineers and entrepreneurs

科学家、工程师和企业家们

are working on methods to pull carbon dioxide

正在致力于研究将二氧化碳

out of these point sources,

赶出这些源头的方法，

so that they're not released into the atmosphere.

这样二氧化碳就不会被释放到空气中。

And they need to put it somewhere.

他们还需要将这些二氧化碳 安置在别的地方。

因为这个原因，

So for this reason,

we need to keep studying places where this carbon might be stored,

我们一直在研究也许能够 储存这些二氧化碳的地方，

possibly in the subsurface,

或许在地表下，

to know what's going to happen to it when it goes there.

需要了解当二氧化碳 在那里时可能会发生的事情。

Will these deep subsurface microbes be a problem because they're too slow

这些深埋于地表下的微生物 是否会成为一个难题，

to actually keep anything down there?

它们行动非常缓慢，是否 真的可以保存那下面的任何东西？

Or will they be helpful

或者，它们会很有用，

because they'll help convert this stuff to solid carbonate minerals?

因为它们可以把二氧化碳 转化成固体的碳酸盐矿物？

If we can make such a big breakthrough

如果我们可以在哥斯达黎加的研究上

just from one study that we did in Costa Rica,

取得重大的科学突破，

then imagine what else is waiting to be discovered down there.

想象一下，那下面还会有 什么东西等待着我们去发现。

This new field of geo-bio-chemistry, or deep subsurface biology,

这个地理生物化学的新领域， 或者深层地下生物学，

or whatever you want to call it,

或者任何你想称呼的名字，

is going to have huge implications,

将会产生巨大的影响，

并不仅仅是缓解气候变化，

not just for mitigating climate change,

but possibly for understanding how life and earth have coevolved,

而可能是对生命和地球共同进化的理解，

or finding new products that are useful for industrial or medical applications.

或者是寻找对工业和 医学应用有效的新产品。

Maybe even predicting earthquakes

或者甚至是预测地震

or finding life outside our planet.

或者寻找地球以外的生命。

It could even help us understand the origin of life itself.

它可能甚至可以帮助 我们理解生命的起源。

Fortunately, I don't have to do this by myself.

幸运的是，在这件事上， 我不是一个人。

I have amazing colleagues all over the world

我在全世界都有着了不起的同事，

who are cracking into the mysteries of this deep subsurface world.

他们闯入了这个深埋于 地表下的世界的奥秘。

And it may seem like life buried deep within the earth's crust

看起来好像深埋于地壳的生命

is so far away from our daily experiences that it's kind of irrelevant.

离我们的日常生活非常遥远， 以致于和我们毫无关系。

But the truth is that this weird, slow life

但是真相就是这个 怪异而又缓慢的生命体

may actually have the answers to some of the greatest mysteries

可能实际上有着 我们地球上的生命中蕴含的

of life on earth.

一些最大奥秘的答案。

Thank you.

谢谢大家。

(Applause)

（掌声）