I'd like to introduce you to a tiny microorganism that you've probably never heard of:
我想向你们介绍一种小小的微生物，你们可能从没有听说过：
its name is Prochlorococcus, and it's really an amazing little being.
它叫原绿球藻，是一种非常神奇的微生物。
For one thing, its ancestors changed the earth in ways that made it possible for us to evolve,
一方面，它的祖先改变了地球环境，使其适合人类的演化，
and hidden in its genetic code is a blueprint that may inspire ways to reduce our dependency on fossil fuel.
而隐藏在其遗传密码中的是一个蓝图，可以启发我们找到减少对化石燃料依赖的方法。
But the most amazing thing is that there are three billion billion billion of these tiny cells on the planet,
但最让人惊奇的是地球上拥有3乘10的27次方之多的这种微生物，
and we didn't know they existed until 35 years ago.
而我们直至35年前才知道它们的存在。
So to tell you their story, I need to first take you way back,
要给你们讲它们的故事，我需要首先带你们回到过去，
four billion years ago, when the earth might have looked something like this.
40亿年前的地球可能长这样。
There was no life on the planet, there was no oxygen in the atmosphere.
毫无生息，大气层中没有一点氧气。
So what happened to change that planet into the one we enjoy today, teeming with life, teeming with plants and animals?
是什么让地球变得像今天这样宜居，充满生命，到处是植物和动物？
Well, in a word, photosynthesis. About two and a half billion years ago,
一个词，光合作用。在大约25亿年前，
some of these ancient ancestors of Prochlorococcus evolved
原绿球藻的部分远古祖先发生了进化，
so that they could use solar energy and absorb it and split water into its component parts of oxygen and hydrogen.
这样它们就可以使用太阳能，吸收这些能量，并利用其将水分解成氧和氢。
And they used the chemical energy produced to draw CO2, carbon dioxide, out of the atmosphere
它们使用产生的化学能把二氧化碳从大气中抽取出来，
and use it to build sugars and proteins and amino acids, all the things that life is made of.
并用于制造糖分、蛋白质和氨基酸，所有这些组成生命的元素。
And as they evolved and grew more and more over millions and millions of years, that oxygen accumulated in the atmosphere.
随着它们不断演化，数量日渐增加，历经数百万年之后，大气中的氧气慢慢积累起来。
Until about 500 million years ago, there was enough in the atmosphere that larger organisms could evolve.
直到大约5亿前，大气中的氧气足够多到让更大的生物可以进化。
There was an explosion of life-forms, and, ultimately, we appeared on the scene.
迎来了生命形态的大爆发，最终，人类出现在了历史舞台上。
While that was going on, some of those ancient photosynthesizers died and were compressed and buried,
在这一切发生的过程中，部分这些远古的光合作用系统死去，被压缩和埋葬，
and became fossil fuel with sunlight buried in their carbon bonds.
变成了用碳键储存太阳能量的化石燃料。
They're basically buried sunlight in the form of coal and oil.
它们基本上是用煤炭和石油的形式储存太阳能的。
Today's photosynthesizers, their engines are descended from those ancient microbes, and they feed basically all of life on earth.
今天的光合作用系统，它们的引擎是那些古老微生物的后代，它们基本上养育了地球上所有的生物。
Your heart is beating using the solar energy that some plant processed for you,
你心脏的跳动使用的是来自植物为你加工的太阳能，
and the stuff your body is made out of is made out of CO2 that some plant processed for you.
你的身体部件是由植物为你加工的二氧化碳制造而成。
Basically, we're all made out of sunlight and carbon dioxide. Fundamentally, we're just hot air.
总的来说，我们都由阳光和二氧化碳所造。说白了，我们只是热空气罢了。
So as terrestrial beings, we're very familiar with the plants on land: the trees, the grasses, the pastures, the crops.
作为陆地生物，我们对地上的植物很熟悉：树木，草，牧场，庄稼。
But the oceans are filled with billions of tons of animals.
但海洋里充满了数十亿吨的动物。
Do you ever wonder what's feeding them?
你们有没有好奇它们都吃些什么？
Well there's an invisible pasture of microscopic photosynthesizers called phytoplankton
海洋里面有一片看不见的牧场，由一种叫做浮游植物的微型光合成器组成，
that fill the upper 200 meters of the ocean, and they feed the entire open ocean ecosystem.
填满了海洋顶层的200米，它们为整个海洋生态系统提供食物。
Some of the animals live among them and eat them, and others swim up to feed on them at night,
有些动物生活于其中，以它们为食，另一些晚上游过来吞食它们，
while others sit in the deep and wait for them to die and settle down and then they chow down on them.
还有一些静坐海洋深处，等待它们死亡，沉降，从而享受美餐。
So these tiny phytoplankton, collectively, weigh less than one percent of all the plants on land,
这些微小的浮游植物加在一起，只占地球植物重量不到1/100，
but annually they photosynthesize as much as all of the plants on land,
但每年它们的光合作用总量不亚于陆地上的所有植物，
including the Amazon rainforest that we consider the lungs of the planet.
包括亚马逊雨林在内，这个我们视为地球之肺的雨林。
Every year, they fix 50 billion tons of carbon in the form of carbon dioxide into their bodies that feeds the ocean ecosystem.
每一年，它们以二氧化碳的形式在体内固定500亿吨的碳，从而为整个海洋系统提供食物。
How does this tiny amount of biomass produce as much as all the plants on land?
这些微小的生物是如何产生跟地上的植物一样多的氧气的呢？
Well, they don't have trunks and stems and flowers and fruits and all that to maintain.
它们并没有树干和茎，鲜花和果实这些维持生命的东西。
All they have to do is grow and divide and grow and divide.
它们所要做的无非是重复地成长和分裂。
They're really lean little photosynthesis machines. They really crank.
它们是非常小的光合作用机器。真是全力以赴地在工作。
So there are thousands of different species of phytoplankton,
有成千上万种不同种类的浮游植物，
come in all different shapes and sizes, all roughly less than the width of a human hair.
有不同的形状和大小，它们的尺寸都小于人类的头发宽度。
Here, I'm showing you some of the more beautiful ones, the textbook versions.
这里，我给大家展示其中最漂亮的一些，几乎是教科书版本。
I call them the charismatic species of phytoplankton.
我称它们为魅力非凡的浮游植物。
And here is Prochlorococcus. I know, it just looks like a bunch of schmutz on a microscope slide.
这就是原绿球藻。我知道，这看起来就像是显微玻璃片上的脏东西。
But they're in there, and I'm going to reveal them to you in a minute.
但它们就在其中，我马上就会展示给你们看。
But first I want to tell you how they were discovered.
但首先，我想告诉大家它们是如何被发现的。
About 38 years ago, we were playing around with a technology in my lab called flow cytometry
在大约38年前，我们在实验室里时兴玩一项叫做流式细胞术的技术，
that was developed for biomedical research for studying cells like cancer cells,
该技术是为研究癌细胞等生物医学研究而开发的，
but it turns out we were using it for this off-label purpose which was to study phytoplankton,
但结果，我们用它来实现这个标示外的目的，用于研究浮游植物，
and it was beautifully suited to do that. And here's how it works:
也是非常适合的。这是它工作的原理：
so you inject a sample in this tiny little capillary tube, and the cells go single file by a laser,
你把样本注入到这个微小的毛细管中，细胞在激光照射下一个个通过，
and as they do, they scatter light according to their size and they emit light according to whatever pigments they might have,
在这过程中，它们根据不同的大小散射光线，并根据它们可能含有的色素发出光，
whether they're natural or whether you stain them.
不管是天然的还是后天被染色的。
And the chlorophyl of phytoplankton, which is green, emits red light when you shine blue light on it.
浮游植物的叶绿素是绿色的，当你把蓝光照射在上面时，就发出红光。
And so we used this instrument for several years to study our phytoplankton cultures,
所以我们使用这种仪器好些年去研究我们的浮游植物培养群，
species like those charismatic ones that I showed you, just studying their basic cell biology.
这种我给你们看的有魅力的物种，只是研究它们基本的细胞生物学。
But all that time, we thought, well wouldn't it be really cool if we could take an instrument like this out on a ship
但在这段时间里，我们想，假如我们把这种仪器带到船上，
and just squirt seawater through it and see what all those diversity of phytoplankton would look like.
用它来喷洒海水，看看多样性的浮游植物会是什么样子，这不是很酷吗？
So I managed to get my hands on what we call a big rig in flow cytometry,
所以我设法得到了我们称之为流式细胞仪中的大钻机，
a large, powerful laser with a money-back guarantee from the company that if it didn't work on a ship, they would take it back.
一个大型、强大的激光器，并得到了卖方假如无法在船上工作，可以退货退款的保证。
And so a young scientist that I was working with at the time, Rob Olson,
于是一个我一直在合作的年轻科学家，罗伯·奥尔森，
was able to take this thing apart, put it on a ship, put it back together and take it off to sea.
把这东西拆开，运到船上，再重新组装好，带到海里去。
And it worked like a charm. We didn't think it would,
它的效果出人意料的好。我们没想到效果这么好，
because we thought the ship's vibrations would get in the way of the focusing of the laser, but it really worked like a charm.
因为我们以为船的晃动会阻碍激光的聚焦，但它的效果真的十分惊艳。
And so we mapped the phytoplankton distributions across the ocean.
于是，我们绘制了整个海洋的浮游植物分布图。
For the first time, you could look at them one cell at a time in real time and see what was going on -- that was very exciting.
这是首次可以实时地看一个细胞单元，看看发生了什么--这实在非常令人兴奋。
But one day, Rob noticed some faint signals coming out of the instrument
有一天，罗伯注意到机器中有一些微弱的信号，
that we dismissed as electronic noise for probably a year before we realized that it wasn't really behaving like noise.
这些信号一年来一直被我们当做电子噪音，直至我们意识到它们并不是噪音。
It had some regular patterns to it. To make a long story short, it was tiny, tiny little cells,
它的信号表现出了一些固定的模式。长话短说，它是非常非常微小的细胞，
less than one-one hundredth the width of a human hair that contain chlorophyl. That was Prochlorococcus.
不到人类头发宽度的百分之一，它含有叶绿素。这就是原绿球藻。
So remember this slide that I showed you?
还记得刚才展示过的这张幻灯片吗？
If you shine blue light on that same sample, this is what you see: two tiny little red light-emitting cells.
如果你用蓝光照射这些样本，就会看到这样一幕：两个微小的红色发光细胞。
Those are Prochlorococcus. They are the smallest and most abundant photosynthetic cell on the planet.
这些都是原绿球藻。它们是地球上最小，但数量最多的光合细胞。
At first, we didn't know what they were, so we called the "little greens."
一开始，我们不知道它们是什么，所以叫它们“小绿”。
It was a very affectionate name for them.
这是一个非常亲切的称呼。
Ultimately, we knew enough about them to give them the name Prochlorococcus, which means "primitive green berry."
最后，我们对它们有了深入的了解，就把它取名叫原绿球藻，意思是“原始的绿色浆果”。
And it was about that time that I became so smitten by these little cells
大概是在那个时候我就被这些小细胞迷住了，
that I redirected my entire lab to study them and nothing else, and my loyalty to them has really paid off.
我把我整个实验室的研究方向都转到了它们身上，而我对它们的忠诚也得到了丰厚的回报。
They've given me a tremendous amount, including bringing me here.
它们带给了我很多，也让我今天能够站在这里。

So over the years, we and others, many others, have studied Prochlorococcus across the oceans
过去那些年，我和很多其他人，穿越了各个海域研究原绿球藻，
and found that they're very abundant over wide, wide ranges in the open ocean ecosystem.
发现它们在开放的海洋生态中的数量十分庞大，且分布广阔。
They're particularly abundant in what are called the open ocean gyres.
它们在公海环流中尤其丰富。
These are sometimes referred to as the deserts of the oceans, but they're not deserts at all.
这些区域有时被称为海洋的沙漠，但它们其实根本不是沙漠。
Their deep blue water is teeming with a hundred million Prochlorococcus cells per liter.
深蓝色的海水每升富含1亿个原绿球藻。
If you crowd them together like we do in our cultures, you can see their beautiful green chlorophyl.
如果把它们按处理培养群那样聚在一起，就可以看到它们美丽的绿色叶绿素。
One of those test tubes has a billion Prochlorococcus in it,
其中一个试管中有10亿个原绿球菌，
and as I told you earlier, there are three billion billion billion of them on the planet.
正如我刚才提到的，地球上有3乘10的27次方的原绿球藻。
That's three octillion, if you care to convert.
相当于3倍的10亿的3次方，如果你想转换的话。
And collectively, they weigh more than the human population and they photosynthesize as much as all of the crops on land.
它们的重量加起来超过了人类总人口的重量，光合作用程度跟地球上所有作物一样多。
They're incredibly important in the global ocean.
它们对全球海洋来说非常重要。
So over the years, as we were studying them and found how abundant they were, we thought, hmm, this is really strange.
这些年来，随着研究的不断推进，我们发现它们的含量如此丰富，不禁感到很奇怪。
How can a single species be so abundant across so many different habitats?
一个物种如何能在如此多的不同栖息地都如此丰富？
And as we isolated more into culture, we learned that they are different ecotypes.
当我们把更多的原绿球藻隔离在培养液中，我们了解到它们是不同的生态类型。
There are some that are adapted to the high-light intensities in the surface water,
有一些适应高光强度的表层水，
and there are some that are adapted to the low light in the deep ocean.
另一些则适应深海的低光环境。
In fact, those cells that live in the bottom of the sunlit zone are the most efficient photosynthesizers of any known cell.
事实上，那些生活在阳光照射区底部的细胞，是所有已知细胞中最有效的光合成器。
And then we learned that there are some strains that grow optimally along the equator, where there are higher temperatures,
然后我们了解到有一些菌株在赤道上生长得最好，那里温度更高，
and some that do better at the cooler temperatures as you go north and south.
有一些则在更低温度中表现更好，沿着经线考察就会发现。
So as we studied these more and more and kept finding more and more diversity,
所以当我们更深入地研究这些问题时，就会不断发现更多的多样性，
we thought, oh my God, how diverse are these things?
我们不禁感叹，老天，这些东西到底有多少种？
And about that time, it became possible to sequence their genomes and really look under the hood and look at their genetic makeup.
大约在那个时候，技术已经发展到可以对它们的基因组进行测序了，可以仔细看看它们的基因组成。
And we've been able to sequence the genomes of cultures that we have,
我们已经能够对所拥有的培养物的基因组进行测序，
but also recently, using flow cytometry, we can isolate individual cells from the wild and sequence their individual genomes,
但也在最近，使用流式细胞术，我们可以将单个细胞从野生环境中分离出来，并对它们的个体基因组进行测序，
and now we've sequenced hundreds of Prochlorococcus.
现在我们已经对数百种原球菌进行了测序。
And although each cell has roughly 2,000 genes -- that's one tenth the size of the human genome -- as you sequence more and more,
尽管每个细胞大约只有2000个基因--是人类基因组的1/10--但随着测序越来越多，
you find that they only have a thousand of those in common
你会发现它们之间有上千种基因是相似的，
and the other thousand for each individual strain is drawn from an enormous gene pool,
而每个个体的另外一千个基因都是从一个巨大的基因库中提取出来的，
and it reflects the particular environment that the cell might have thrived in,
它反映了细胞可能在其中生长的特殊环境，
not just high or low light or high or low temperature,
不只是在光照强度和温度上有差别，
but whether there are nutrients that limit them like nitrogen, phosphorus or iron.
还包括是否有营养物质限制了它们，比如氮、磷或铁。
It reflects the habitat that they come from.
同时也反映了它们的栖息地。
Think of it this way. If each cell is a smartphone and the apps are the genes,
可以这样想。如果每个细胞是部智能手机，应用是基因，
when you get your smartphone, it comes with these built-in apps.
当你拿到智能手机时，它已经预装了一些应用。
Those are the ones that you can't delete if you're an iPhone person.
如果你用的是iPhone，这些预装应用你是无法删除的。
You press on them and they don't jiggle and they don't have x's.
你按下它们，它们不会抖动，不会出现删除标记。
Even if you don't want them, you can't get rid of them.
即便你不喜欢它们，也别想清除掉它们。
Those are like the core genes of Prochlorococcus. They're the essence of the phone.
这些是原绿球藻的核心基因。它们就像手机的核心。
But you have a huge pool of apps to draw upon to make your phone custom-designed for your particular lifestyle and habitat.
但你也有一个巨大的应用库，可以根据你的生活方式和习惯来对你的手机进行个性化设置。
If you travel a lot, you'll have a lot of travel apps,
如果你到处旅行，就会有很多旅行应用，
if you're into financial things, you might have a lot of financial apps,
如果你是搞金融的，可能就有很多财经应用，
or if you're like me, you probably have a lot of weather apps, hoping one of them will tell you what you want to hear.
或者如果你像我一样，你可能会有一大堆天气应用，希望里面起码有一个预测能让你心花怒放。
And I've learned the last couple days in Vancouver that you don't need a weather app -- you just need an umbrella. So...
我在温哥华最后几天学到的是你未必需要天气应用，你只需要一把伞。所以...
So just as your smartphone tells us something about how you live your life, your lifestyle,
所以正如你的智能手机能够告诉我们一些你的生活，你的生活方式那样，
reading the genome of a Prochlorococcus cell tells us what the pressures are in its environment.
阅读原绿球藻细胞的基因能够告诉我们原绿球藻所生活的环境，比如压力强度。
It's like reading its diary, not only telling us how it got through its day or its week, but even its evolutionary history.
就如同阅读它的日记，不仅告诉我们它的一天，或一周如何度过，甚至还包括它们的演化历史。
As we studied -- I said we've sequenced hundreds of these cells,
随着进一步的研究，我们已经测序了几百种这些细胞，
and we can now project what is the total genetic size -- gene pool -- of the Prochlorococcus federation, as we call it.
我们现在已经可以预估整个基因集合的大小--基因库--原绿球藻的基因联邦，我们是这样称呼它的。
It's like a superorganism. And it turns out that projections are that the collective has 80,000 genes.
这就像一个超级有机体。预测的结果是整个集合共有8万个基因。
That's four times the size of the human genome.
相当于人类基因组的4倍。
And it's that diversity of gene pools that makes it possible for them to dominate these large regions of the oceans
正是这多样化的基因库让它们可以统治这广阔的海域，
and maintain their stability year in and year out.
一年接一年地维持它们的稳定性。
So when I daydream about Prochlorococcus, which I probably do more than is healthy...
当我畅想着原绿球藻的的时候，我做这个可不仅是为了健康...
I imagine them floating out there, doing their job, maintaining the planet, feeding the animals.
我想象它们漂来漂去，做着本职工作，维持地球的运转，喂饱动物。
But also I inevitably end up thinking about what a masterpiece they are, finely tuned by millions of years of evolution.
但同时也不可避免想到它们真是大自然的鬼斧神工，历经了数百万年精细的进化。
With 2,000 genes, they can do what all of our human ingenuity has not figured out how to do yet.
只有2000个基因，它们就做到了我们人类还没有搞明白怎么做的事情。
They can take solar energy, CO2 and turn it into chemical energy in the form of organic carbon,
它们可以把太阳能，CO2以有机碳的方式变成化学能，
locking that sunlight in those carbon bonds.
把阳光锁在那些碳键中。
If we could figure out exactly how they do this,
如果我们能够弄明白它们是如何做到的，
it could inspire designs that could reduce our dependency on fossil fuels, which brings my story full circle.
就可以激发我们设计一些方法来减少对化学燃料的依赖，这也就让我的故事圆满了。
The fossil fuels that are buried that we're burning took millions of years for the earth to bury those,
我们用来燃烧的埋葬在地下的化石燃料，需要地球花费长达数百万年的时间去积累，
including those ancestors of Prochlorococcus, and we're burning that now in the blink of an eye on geological timescales.
包括这些原绿球藻的远古祖先，而我们眨眼之间就把它们燃烧了，从地质时间的尺度来看就是一瞬间。
Carbon dioxide is increasing in the atmosphere. It's a greenhouse gas.
二氧化碳在大气中积累。这是一种温室气体。
The oceans are starting to warm. So the question is, what is that going to do for my Prochlorococcus?
海洋开始变得温暖。所以问题是，我的原绿球藻接下来会怎样？
And I'm sure you're expecting me to say that my beloved microbes are doomed, but in fact they're not.
我确定你们会觉得我想说，我心爱的微生物要遭受灭顶之灾了，但事实并非如此。
Projections are that their populations will expand as the ocean warms to 30 percent larger by the year 2100.
我们的预测是，随着海水温度上升，它们的数量会在2100年增加30%。
Does that make me happy? Well, it makes me happy for Prochlorococcus of course -- but not for the planet.
这让我们开心了吗？当然，这让我为原绿球藻感到高兴--但对地球可就不是这么回事儿了。
There are winners and losers in this global experiment that we've undertaken,
在这场我们正在进行的全球实验中，难免会有输家和赢家，
and it's projected that among the losers will be some of those larger phytoplankton,
而根据预计，输家是那些更大一些的浮游植物，
those charismatic ones which are expected to be reduced in numbers,
那些有魅力的预期数量会大为减少，
and they're the ones that feed the zooplankton that feed the fish that we like to harvest.
它们是为人类喜欢捕捞的鱼类提供食物的浮游植物。
So Prochlorococcus has been my muse for the past 35 years,
在过去35年中，原绿球藻就是我的命运女神，
but there are legions of other microbes out there maintaining our planet for us.
但还有很多其他的微生物在帮我们维持地球的环境平衡。
They're out there ready and waiting for us to find them so they can tell their stories, too. Thank you.
它们就在那儿，准备就绪，等待着我们去寻找它们并传颂它们的故事。谢谢。