演讲MP3+双语文稿:生活在地球深处的神秘微生物如何帮助人类
听力课堂TED音频栏目主要包括TED演讲的音频MP3及中英双语文稿，供各位英语爱好者学习使用。本文主要内容为演讲MP3+双语文稿:生活在地球深处的神秘微生物如何帮助人类，希望你会喜欢！
【演讲者及介绍】Karen Lloyd
凯伦·劳埃德研究地球深层生物圈的新型微生物，从遥远的地方收集它们，比如北极峡湾、哥斯达黎加的火山，甚至是马里亚纳海沟附近的泥地深处。
【演讲主题】生活在地球深处的神秘微生物以及它们如何帮助人类
【中英文字幕】
翻译者 Jingdan Niu 校对者 Cissy Yun
00:13
It may seem like we're all standing onsolid earth right now, but we're not. The rocks and the dirt underneath us arecrisscrossed by tiny little fractures and empty spaces. And these empty spacesare filled with astronomical quantities of microbes, such as these ones. Thedeepest that we found microbes so far into the earth is five kilometers down.So like, if you pointed yourself at the ground and took off running into theground, you could run an entire 5K race and microbes would line your wholepath.
看起来我们现在都站在坚固的地球表面上，然而并不是。在我们脚下的石头和尘土里交叉分布着细小的断裂层和空隙。这些空隙中充满天文数量级的微生物，比如这些。目前我们可以找到微生物的最大深度是地下5000米。所以，如果你在地面上定一个点位，然后开始向地心跑，沿途5000米的路径上都能看到微生物。
00:45
So you may not have ever thought aboutthese microbes that are deep inside earth's crust, but you probably thoughtabout the microbes living in our guts. If you add up the gut microbiomes of allthe people and all the animals on the planet, collectively, this weighs about100,000 tons. This is a huge biome that we carry in our bellies every singleday. We should all be proud.
所以你可能从来没想到这些微生物还存在于地壳的深处，但是你可能会想到生活在我们内脏里的微生物。如果你将地球上所有生物的内脏微生物全部加在一起，它们的重量约有10万吨。每一天，这么庞大的生物群就生活在我们的肚子里。我们都应该感到非常骄傲。
01:08
(Laughter)
（笑声）
01:09
But it pales in comparison to the number ofmicrobes that are covering the entire surface of the earth, like in our soils,our rivers and our oceans. Collectively, these weigh about two billion tons.But it turns out that the majority of microbes on earth aren't even in oceansor our guts or sewage treatment plants. Most of them are actually inside theearth's crust. So collectively, these weigh 40 billion tons. This is one of thebiggest biomes on the planet, and we didn't even know it existed until a fewdecades ago. So the possibilities for what life is like down there, or what itmight do for humans, are limitless.
但是相对于可以覆盖整个地球表面的微生物，比如在土壤里、河里和海里的微生物，内脏里的微生物就显得相形见绌了。它们加起来约有20亿吨。但是事实说明大部分地球上的微生物并不是在我们的内脏或者污水处理厂里。实际上，它们大多数都在地壳里。所以这些加起来有400亿吨重。这是地球上最大的微生物群之一，而我们在几十年前才发现它们的存在。所以地球下的生活是什么样，或者它们对人类的影响无法估量。
02:15
So people sometimes say to me, "Yeah,there's a lot of microbes in the subsurface, but ... aren't they just kind ofdormant?" This is a good point. Relative to a ficus plant or the measlesor my kid's guinea pigs, these microbes probably aren't doing much of anythingat all. We know that they have to be slow, because there's so many of them. Ifthey all started dividing at the rate of E. coli, then they would double theentire weight of the earth, rocks included, over a single night. In fact, manyof them probably haven't even undergone a single cell division since the timeof ancient Egypt. Which is just crazy. Like, how do you wrap your head aroundthings that are so long-lived?
有时候有人跟我说，“没错，地表下有很多微生物，但是……它们不是在冬眠吗？”这是非常好的一个问题。当比无花果属植物或者麻疹，或者是我小孩养的那些豚鼠，这些微生物大概真的是什么事情都不做。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。如果它们按照大肠杆菌的速度开始分裂，仅仅一夜之间，它们就让整个地球，包括石头的重量翻倍。实际上，从古埃及时代以后，很多微生物大概甚至没有完成过一次细胞分裂。这真是太神奇了。我们到底该如何去看待这样长寿的东西？
03:00
But I thought of an analogy that I reallylove, but it's weird and it's complicated. So I hope that you can all go therewith me. Alright, let's try it. It's like trying to figure out the life cycleof a tree ... if you only lived for a day. So like if human life span was onlya day, and we lived in winter, then you would go your entire life without everseeing a tree with a leaf on it. And there would be so many human generationsthat would pass by within a single winter that you may not even have access toa history book that says anything other than the fact that trees are always lifelesssticks that don't do anything. Of course, this is ridiculous. We know thattrees are just waiting for summer so they can reactivate. But if the human lifespan were significantly shorter than that of trees, we might be completelyoblivious to this totally mundane fact.
但是我想到了一个我非常喜欢的类比，虽然它听起来会有些奇怪和复杂。我希望你们可以听听看。好的，让我们试试。这个类比就像是试图理解一棵树的生命周期……如果你只能活一天。所以假如人类的生命只有一天，并且是在冬天，那么你的整个人生，都不会在树上看到任何一片叶子。在仅仅一个冬天里，人类就会拥有非常多的后代子孙，以致于历史书上只会记载树木 是一个没有生命的棍子，没啥用处。当然，这种结论很荒唐。我们知道树木只是在等待夏天的到来，这样它们就可以恢复活力。但是假如人类的寿命明显比树木的寿命短，我们可能就完全不会察觉到这个非常平凡的事实。
03:49
So when we say that these deep subsurfacemicrobes are just dormant, are we like people who die after a day, trying tofigure out how trees work? What if these deep subsurface organisms are just waitingfor their version of summer, but our lives are too short for us to see it? Ifyou take E. coli and seal it up in a test tube, with no food or nutrients, andleave it there for months to years, most of the cells die off, of course,because they're starving. But a few of the cells survive. If you take these oldsurviving cells and compete them, also under starvation conditions, against anew, fast-growing culture of E. coli, the grizzled old tough guys beat out thesqueaky clean upstarts every single time. So this is evidence there's actuallyan evolutionary payoff to being extraordinarily slow. So it's possible thatmaybe we should not equate being slow with being unimportant. Maybe theseout-of-sight, out-of-mind microbes could actually be helpful to humanity.
所以当我们说这些深埋于地下的微生物只是在沉睡，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？这些地表下的微生物会不会只是在等待它们的“夏天”，而我们只是因为生命太短暂而无法看到？如果你将大肠杆菌封闭在一个试管里，没有食物或者营养剂给它，然后将它成年累月的放在那里不管，当然，大部分细胞都会饿死。但是很小一部分细胞会生存下来。如果你取下这些年老的存活下来的细胞，让它们在饥饿的条件下，和一些新的、快速成长的大肠杆菌竞争，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干净的新贵。所以，这证明了进化的格外缓慢 其实有好处。所以有可能，我们也许不应该将慢等同于不重要。也许这些看不见的，我们不放在心上的微生物实际上对人类是有帮助的。
04:56
OK, so as far as we know, there are twoways to do subsurface living. The first is to wait for food to trickle downfrom the surface world, like trying to eat the leftovers of a picnic thathappened 1,000 years ago. Which is a crazy way to live, but shockingly seems towork out for a lot of microbes in earth. The other possibility is for a microbeto just say, "Nah, I don't need the surface world. I'm good downhere." For microbes that go this route, they have to get everything thatthey need in order to survive from inside the earth. Some things are actuallyeasier for them to get. They're more abundant inside the earth, like water ornutrients, like nitrogen and iron and phosphorus, or places to live. These arethings that we literally kill each other to get ahold of up at the surfaceworld.
目前我们所知道的是，有两种方法让它们在地表下的生活。第一种是等待食物从地表向下滴流，这就好像尝试吃从一千年前的野餐上剩下来的食物。真是个疯狂的生活方式。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。另外一种方式是，微生物会觉得，“我不需要地表世界，我在这下面挺好的。”对于选择这条路的微生物来说，它们为了生存，不得不从地球内部来获取它们所需求的一切。实际上，有些东西对它们来说比较容易获得。这些东西在地球里面更加充足，比如水源或者营养，比如氮、铁和磷，或者可以居住的地方。这些是我们在地表世界上需要靠互相厮杀 来得到的东西。
05:44
But in the subsurface, the problem isfinding enough energy. Up at the surface, plants can chemically knit togethercarbon dioxide molecules into yummy sugars as fast as the sun's photons hittheir leaves. But in the subsurface, of course, there's no sunlight, so thisecosystem has to solve the problem of who is going to make the food foreverybody else. The subsurface needs something that's like a plant but itbreathes rocks. Luckily, such a thing exists, and it's called achemolithoautotroph.
但是在地表下，它们只需要担心是否有足够的能量。在地表上，当太阳光子照到植物的叶子上时，它们可以尽快地将二氧化碳分子转化成美味的糖分。但是在地表下，当然了，那里没有阳光，所以这个生态系统不得不解决这个问题：谁来给其它的微生物制造食物。地表下需要像植物那样的东西，但是呼吸的是石头。幸运的是，存在这么一个东西，叫做化能无机自养生物。
06:17
(Laughter)
（笑声）
06:18
Which is a microbe that uses chemicals --"chemo," from rocks -- "litho," to make food --"autotroph." And they can do this with a ton of different elements.They can do this with sulphur, iron, manganese, nitrogen, carbon, some of themcan use pure electrons, straight up. Like, if you cut the end off of an electricalcord, they could breathe it like a snorkel.
这个单词是由一个微生物利用化学物质——“chemo”从石头里——"litho"，生产食物——"autotroph"。它们可以用大量不同的元素。它们可以用硫磺、铁、镁、氮、碳，其中有些可以直接用纯电子。就像是，如果你切掉一个电线的尾部，它们可以用它呼吸，就像潜水通气管那样。
06:42
(Laughter)
（笑声）
06:43
These chemolithoautotrophs take the energythat they get from these processes and use it to make food, like plants do. Butwe know that plants do more than just make food. They also make a wasteproduct, oxygen, which we are 100 percent dependent upon. But the waste productthat these chemolithoautotrophs make is often in the form of minerals, likerust or pyrite, like fool's gold, or carminites, like limestone. So what wehave are microbes that are really, really slow, like rocks, that get theirenergy from rocks, that make as their waste product other rocks. So am Italking about biology, or am I talking about geology? This stuff really blursthe lines.
这些化能无机自养生物将这个过程中得到的能量用来制造食物，就像植物那样。但是我们知道植物并不仅仅只是制造食物。它们也可以制造一种多余的产物，氧气，这是我们百分之百赖以生存的东西。但是这些化能无机自养生物制造的多余的产物则是矿物，比如锈或者黄铁矿，包括愚人金，或者碳酸盐，包括石灰岩。我们的微生物，就像石头那样，变化非常非常慢，它们从石头里获取能量，来制造的多余的产物，还是石头。所以我是在讨论生物，还是在讨论地理？这个东西真的很难定义。
07:32
(Laughter)
（笑声）
07:33
So if I'm going to do this thing, and I'mgoing to be a biologist who studies microbes that kind of act like rocks, thenI should probably start studying geology. And what's the coolest part ofgeology? Volcanoes.
如果我要研究微生物，并且我将要作为一名生物学家来研究这种行为像石头一样的微生物，那么，我大概应该开始学习地理了。那么，地理最酷的部分是什么呢？火山。
07:49
(Laughter)
（笑声）
07:50
Many volcanoes on earth arise because anoceanic tectonic plate crashes into a continental plate. As this oceanic platesubducts or gets moved underneath this continental plate, things like water andcarbon dioxide and other materials get squeezed out of it, like ringing a wetwashcloth. So in this way, subduction zones are like portals into the deepearth, where materials are exchanged between the surface and the subsurfaceworld.
地球上许多火山是由于海洋地壳构造板块撞上大陆板块而出现的。当海洋板块下沉或移动到大陆板块下面时，像水和二氧化碳以及其它的物质就被挤压脱离了大陆板块，就像箍住了一块湿毛巾。这样一来，俯冲带就成了通往地壳的传送带，在这里，地表和地表下的物质得以相互交换。
08:18
So I was recently invited by some of mycolleagues in Costa Rica to come and work with them on some of the volcanoes.And of course I said yes, because, I mean, Costa Rica is beautiful, but alsobecause it sits on top of one of these subduction zones. We wanted to ask thevery specific question: Why is it that the carbon dioxide that comes out ofthis deeply buried oceanic tectonic plate is only coming out of the volcanoes?Why don't we see it distributed throughout the entire subduction zone? Do themicrobes have something to do with that?
最近我收受到一些在哥斯达黎加的同事邀请，和他们一起对一些火山进行研究。当然，我同意了，因为我觉得哥斯达黎加很漂亮，但是也是因为哥斯达黎加位于这其中一个俯冲带的上方。我们想问一个非常具体的问题：为什么从这个深埋的海洋板块中释放出来的二氧化碳只能来自火山呢？为什么它没有分部在整个俯冲带？这和微生物会不会有什么联系？
08:49
So this is a picture of me inside PoásVolcano, along with my colleague Donato Giovannelli. That lake that we'restanding next to is made of pure battery acid. I know this because we weremeasuring the pH when this picture was taken. And at some point while we wereworking inside the crater, I turned to my Costa Rican colleague Carlos Ramírezand I said, "Alright, if this thing starts erupting right now, what's ourexit strategy?" And he said, "Oh, yeah, great question, it's totallyeasy. Just turn around and enjoy the view."
这是我和我的同事多纳托·吉欧瓦内利在珀阿斯火山里的一张照片。在我们旁边的是一个由纯蓄电池酸液构成的湖泊，拍这张照片的时候我们正在测试pH值。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，“如果这个东西现在开始喷发，我们有什么逃生策略吗？”然后他说，“哦，当然了，好问题，这非常简单，转过身欣赏一下这个景象。”
09:22
(Laughter)
（笑声）
09:23
"Because it will be your last."
“因为这将是你最后看到的风景。”
09:25
(Laughter)
（笑声）
09:26
And it may sound like he was being overlydramatic, but 54 days after I was standing next to that lake, this happened.
这可能听起来是过于夸张了，但是在54天之后，这一幕发生了。
09:36
Audience: Oh!
观众：啊！
09:37
Freaking terrifying, right?
太吓人了，是吧？
09:39
(Laughs)
（笑声）
09:41
This was the biggest eruption this volcanohad had in 60-some-odd years, and not long after this video ends, the camerathat was taking the video is obliterated and the entire lake that we had beensampling vaporizes completely. But I also want to be clear that we were prettysure this was not going to happen on the day that we were actually in thevolcano, because Costa Rica monitors its volcanoes very carefully through theOVSICORI Institute, and we had scientists from that institute with us on thatday. But the fact that it erupted illustrates perfectly that if you want tolook for where carbon dioxide gas is coming out of this oceanic plate, then youshould look no further than the volcanoes themselves.
这是这个火山在60多年来发生的最大的一次喷发，并且在拍完这段视频之后，拍摄这个视频的摄像机就模糊了，并且我们曾经取样的整个湖泊完全蒸发了。但是我也想申明，在火山现场的那一天，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对火山进行了非常细致的观测，并且那一天也有研究所的科学家与我们同行。但是火山喷发完美的说明了如果你想找二氧化碳是从海洋板块的哪个位置产生的，没有比观察火山本身更好的机会了。
10:20
But if you go to Costa Rica, you may noticethat in addition to these volcanoes there are tons of cozy little hot springsall over the place. Some of the water in these hot springs is actually bubblingup from this deeply buried oceanic plate. And our hypothesis was that thereshould be carbon dioxide bubbling up with it, but something deep undergroundwas filtering it out.
但是如果你去哥斯达黎加，除了火山，你还应该注意到这里遍地都是舒适的温泉。这些温泉里的一些水源实际上就是深埋于海洋板块之下的气泡上升而成的。而我们的假设就是二氧化碳应该会和气泡一起上升，但是一些地下的东西将它过滤掉了。
10:42
So we spent two weeks driving all aroundCosta Rica, sampling every hot spring we could find -- it was awful, let metell you. And then we spent the next two years measuring and analyzing data.And if you're not a scientist, I'll just let you know that the big discoveriesdon't really happen when you're at a beautiful hot spring or on a public stage;they happen when you're hunched over a messy computer or you're troubleshootinga difficult instrument, or you're Skyping your colleagues because you are completelyconfused about your data. Scientific discoveries, kind of like deep subsurfacemicrobes, can be very, very slow.
所以我们用了两周的时间，在哥斯达黎加将我们可以找到的所有温泉都取样了——大家都疲惫不堪。然后我们花了接下来两年时间测量和分析数据。如果你不是一个科学家，我现在告诉你科研发现一般不会在一个漂亮的温泉里或者公共演讲台上发生；它们发生在你弓着腰坐在一个凌乱的电脑前的时候，或者你在排查一个复杂仪器的故障的时候，或者你在和你的同事视频的时候，因为你已经完全看不懂数据了。科研发现就像是深层地表下的微生物，这个过程是非常、非常慢的。
11:20
But in our case, this really paid off thisone time. We discovered that literally tons of carbon dioxide were coming outof this deeply buried oceanic plate. And the thing that was keeping themunderground and keeping it from being released out into the atmosphere was thatdeep underground, underneath all the adorable sloths and toucans of Costa Rica,were chemolithoautotrophs. These microbes and the chemical processes that werehappening around them were converting this carbon dioxide into carbonatemineral and locking it up underground.
但对我们来说，花这些时间是值得的。我们发现，表面上，大量的二氧化碳是来自于这个深埋的海洋板块。而让它们始终存在于地下并且让它们无法被释放到空气中的则是这个深藏于地下的，在哥斯达黎加所有可爱的树懒和巨嘴鸟下面的，化能无机自养生物。这些微生物和它们周围的化学过程将二氧化碳转化成碳酸盐矿物，并且将它们留在在地表之下。
11:52
Which makes you wonder: If these subsurfaceprocesses are so good at sucking up all the carbon dioxide coming from belowthem, could they also help us with a little carbon problem we've got going on upat the surface? Humans are releasing enough carbon dioxide into our atmospherethat we are decreasing the ability of our planet to support life as we know it.And scientists and engineers and entrepreneurs are working on methods to pullcarbon dioxide out of these point sources, so that they're not released intothe atmosphere. And they need to put it somewhere. So for this reason, we needto keep studying places where this carbon might be stored, possibly in thesubsurface, to know what's going to happen to it when it goes there.
这会让你们感到奇怪：如果这些地表下的过程如此重要，可以把地面下产生的二氧化碳全部吸收，那它们能不能针对我们地表上的二氧化碳问题帮上一点忙？我们知道，人类往空气中释放了太多的二氧化碳，以致于减弱了我们的地球维护生命的能力。科学家、工程师和企业家们正在致力于研究将二氧化碳赶出这些源头的方法，这样二氧化碳就不会被释放到空气中。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，我们一直在研究也许能够储存这些二氧化碳的地方，或许在地表下，需要了解当二氧化碳在那里时可能会发生的事情。
12:35
Will these deep subsurface microbes be aproblem because they're too slow to actually keep anything down there? Or willthey be helpful because they'll help convert this stuff to solid carbonateminerals? If we can make such a big breakthrough just from one study that wedid in Costa Rica, then imagine what else is waiting to be discovered downthere.
这些深埋于地表下的微生物是否会成为一个难题，它们行动非常缓慢，是否真的可以保存那下面的任何东西？或者，它们会很有用，因为它们可以把二氧化碳转化成固体的碳酸盐矿物？如果我们可以在哥斯达黎加的研究上取得重大的科学突破，想象一下，那下面还会有什么东西等待着我们去发现。
12:54
This new field of geo-bio-chemistry, ordeep subsurface biology, or whatever you want to call it, is going to have hugeimplications, not just for mitigating climate change, but possibly forunderstanding how life and earth have coevolved, or finding new products thatare useful for industrial or medical applications. Maybe even predictingearthquakes or finding life outside our planet. It could even help usunderstand the origin of life itself.
这个地理生物化学的新领域，或者深层地下生物学，或者任何你想称呼的名字，将会产生巨大的影响，并不仅仅是缓解气候变化，而可能是对生命和地球共同进化的理解，或者是寻找对工业和医学应用有效的新产品。或者甚至是预测地震或者寻找地球以外的生命。它可能甚至可以帮助我们理解生命的起源。
13:23
Fortunately, I don't have to do this bymyself. I have amazing colleagues all over the world who are cracking into themysteries of this deep subsurface world. And it may seem like life buried deepwithin the earth's crust is so far away from our daily experiences that it'skind of irrelevant. But the truth is that this weird, slow life may actuallyhave the answers to some of the greatest mysteries of life on earth.
幸运的是，在这件事上，我不是一个人。我在全世界都有着了不起的同事，他们闯入了这个深埋于地表下的世界的奥秘。看起来好像深埋于地壳的生命离我们的日常生活非常遥远，以致于和我们毫无关系。但是真相就是这个怪异而又缓慢的生命体可能实际上有着 我们地球上的生命中蕴含的 一些最大奥秘的答案。
13:52
Thank you.
谢谢大家。
13:54
(Applause)
（掌声）
