f we just take the time to observe it, nature provides us with a fascinating spectacle. Earth is the planet of life.
如果我們肯花時間去觀察，會發現大自然為我們提供了一個迷人的奇觀。地球是一個滿是生命的星球。
Running, crawling or flying, life abounds everywhere. But for all this beautiful diversity to have proliferated, Earth has had to provide a favourable environment for around four billion years.
奔跑著的、爬行著的或飛翔著的，到處都是生命。但是，為了讓這些美麗的多樣性得以增殖，地球必須在大約40億年的時間裡一直為它們提供一個有利的環境。
What, then, were the conditions which enabled the blooming of life on Earth? And could these conditions be present elsewhere, resulting in alternative ecosystems?
那麼，使地球上生命繁盛的條件是什麼呢？這些條件會不會出現在其他地方，導致一種另類的生態系統呢？
In an attempt to answer these questions, scientists scour the cosmos for signs of life. They've built giant telescopes with which to probe the universe and listen to the whispering of the stars.
為了回答這些問題，科學家在宇宙中尋找著生命的跡象。他們建造了巨大的望遠鏡，用它來探測宇宙，聆聽星星的低語。
But space has remained resolutely silent. Scientists have sent probes to the very edges of our Solar System.
但太空一直堅決地保持著沉默。科學家們已經向太陽系的邊緣發射了探測器。
But all they have sent back have been images of planets inimical to life. Over the last 25 years, however, astronomers have discovered thousands of incredibly diverse planets, in our galaxy alone.
但他們發回的都是與對生命有害的行星的圖像。然而，在過去的25年裡，天文學家僅在我們的星系中就發現了成千上萬種不同的行星。
So many strange worlds, with no sign of life. Not one other planet similar to our own.
有那麼多奇怪的世界，卻沒有生命的跡象。沒有任何一個星球與我們的地球相似。
So could it be that Earth really is unique? All living things on Earth are made of the same building blocks, long carbon-based molecules.
所以地球真的是獨一無二的嗎？地球上所有的生物都有著相同的組成成分，即長碳基分子。
Scientists now think that a large proportion of these molecules came from outside planet Earth. Comets and asteroids could be the missing links of a long chain.
科學家們現在認為，這些分子中有很大一部分來自地球以外的星球。彗星和小行星可能是生命的長鏈中缺失的環節。
The chain began with the simple molecules found in the early cloud dusts, and culminated with the building blocks of life from which life on Earth first sprang. The chain leading to life.
這條鏈條從早期雲塵中發現的簡單分子開始，到形成生命的基石，地球上的生命就是從這些基石開始萌芽的。一條生命之鏈。
But this carbonaceous material that ended up in Earth's oceans had been through a whole series of changes, particular temperatures, particular events, a particular star, very particular radiation from our own Sun.?
This organic matter was constantly altered on its long journey towards our planet, its final composition the product of a singular history which scientists are now attempting to reconstruct.
但是這些最終進入地球海洋的碳質物質經歷了一系列的變化，特定的溫度、特定的事件、特定的恆星、來自太陽的特定量的輻射。這些有機物質在向我們的星球行進的過程中不斷地被改變，它的最終組成是一段奇特歷史的產物，科學家們現在正試圖重建這段歷史。
To understand what happened to these comets during their transformation and journey through the Solar System, Louis d'Hendecourt and Grégoire Danger have taken an original approach, which doesn't require long and costly interplanetary travel. More a trip in a test-tube.
為了了解這些彗星在太陽系的轉變和旅行過程中發生了什麼，路易斯·亨德古和格雷瓜爾·丹吉爾採取了一種獨創的方法，不需要長時間和昂貴的行星際旅行。更像是在時光裡旅行。
There's the idea of a journey, which is quite poetic, but it's framed in a very scientific context. Here in their laboratory in Marseille, the scientists simulate the formation of a comet and its journey to Earth.
有一個關於旅行的很有詩意的想法，但它是在一個非常科學的背景下形成的。在馬賽的實驗室裡，科學家們模擬了一顆彗星的形成和它的地球之旅。
So, how do we do this? Comets are made of ice and dust.
那麼，我們該怎麼做呢？彗星是由冰和塵埃構成的。
We make some ice. We chose three molecules likely to be in such ice, water, methanol and ammonia.
我們做了一些冰。我們選擇了三種可能存在於冰中的分子，水，甲醇和氨。
The water first? Yeah. Tell me when.
先是水嗎？是的，告訴我什麼時候加。
Then I'll add the methanol. Yeah, okay.
然後我會加入甲醇。好。
This icy material is similar to that of which the newly formed comets were composed. Next, the artificial comet's long journey is simulated in fast-forward.
這種冰物質與新形成的彗星組成的冰物質相似。接下來，以快進的方式模擬人造彗星的長途旅行。
We know that a week in the lab represents a million years. Tell me when you switch it on.
我們知道在實驗室裡一個星期代表了一百萬年。打開開關時告訴我。
Then I'll do the compressed air. The experiment begins.
然後我來壓縮空氣。實驗開始了。
In the chemical reactor there's a vacuum very close to that of interstellar space. And the temperature is minus 200° Celsius.
在化學反應堆中有一個非常接近星際空間的真空空間。溫度是- 200攝氏度。
We made the ice, we can see a bit here, a sort of growth on the edge of the window. The ice is bathed in ultra-violet light, simulating solar radiation, which breaks up the molecules.
我們製作了冰，我們可以看到，在窗戶的邊緣生長著一種東西。冰沐浴在紫外線中，模擬太陽輻射分解分子。
This first stage produces simple molecules, which can then recombine to make more complex molecules if this astonishing experiment is successful. What we're going to do now is warm the system a little to see what the ice does.
第一步產生簡單的分子，如果這個驚人的實驗成功的話，這些簡單的分子就可以重新組合成更複雜的分子。我們現在要做的是加熱一點這個系統，看看冰會怎麼樣。
Then begins the second part of the experiment. The comet leaves the outer region of the Solar System and approaches the warmer zone where Earth is.
然後開始實驗的第二部分。彗星離開太陽系的外部區域，接近地球所在的溫暖地帶。
You can see the ice disappearing. After a moment, you can see bubbles forming.
你可以看到冰正在消失。過一會兒，你可以看到氣泡形成。
So we're approaching a phase where the water is close to leaving the ice. Once we lose the water, we see a whitish film on the surface.
所以我們正在接近一個水將要脫離冰的階段。一旦失去水，我們就會在表面看到一層白色的薄膜。
That's new molecules that have formed. At the end, we have tiny droplets on the surface of the window which are quite visible to the eye.
這是新形成的分子。最後，我們在窗戶表面看到了肉眼可見的小水滴。
And they constitute the organic matter that's been formed from the initial ice which was irradiated, then warmed. The temperature in the reactor is now around 20°Celsius.
它們構成了由最初的冰形成的有機物，這些冰先是被輻射，然後被加熱。反應堆的溫度現在大約是20攝氏度。
The artificial comet has finished its transformative journey. At the end, we get thousands of different kinds of molecules.
人造彗星已經完成了它的變革性旅程。最後，我們得到了成千上萬種不同的分子。
We start with just three molecules water, methanol and ammonia. We apply energy to them, and we form thousands of other molecules.
一開始只有3分子水、甲醇和氨。我們對它們施加能量，就形成了成千上萬的其他分子。
The experiment was a success. In the small chemical reactor, there are now simple organic molecules, similar to the building blocks from which life sprang forth.
實驗成功了。在這個小的化學反應器中，現在有了簡單的有機分子，類似於生命起源的基礎。
Among these molecules, harbingers of life, there are amino acids, the base of all proteins found in every living creature. Also in these droplets there are sugars, essential for the construction of DNA.
在這些孕育生命的分子中有胺基酸，它是每種生物體內所有蛋白質的基礎。在這些液滴中還有糖，它對 DNA 的構建至關重要。
So molecules like this ended up on Earth. In fact, what we call meteorites are pieces broken away from comets and asteroids that came in our atmosphere and left their extra-terrestrial organic matter on the surface of primitive Earth.
這樣的分子最終來到了地球上。事實上，我們所說的隕石是來自彗星和小行星的碎片，它們進入了我們的大氣層，把其地外有機物質留在了原始地球的表面。
Having travelled from the outer reaches of our Solar System, this organic matter ended its journey in the oceans of primitive Earth. Now we need to know what the environmental parameters were which allowed this matter to keep reassembling until it formed living organisms.
這些有機物從太陽系的外圍到達地球，在原始地球的海洋中結束了它們的旅程。現在我們需要知道是什麼環境參數使得這些物質能夠不斷重組直到形成生命體。
This is the next step of this ground-breaking experiment. The organic matter produced by the artificial comet is placed in an environment close to that of primitive Earth.
這是這項開創性實驗的下一步。人造彗星產生的有機物被放置在接近原始地球的環境中。
With this experimental approach, we can change the environmental conditions. We can change, for example, the water temperature, we can change the wavelength of the imaginary sun that we're using…
通過這種實驗方法，我們可以改變環境條件。例如，我們可以改變水溫，我們可以改變我們正在使用的假想太陽的波長。
That's very important for determining the various parameters. Are they limited or not?
這對於確定各種參數是非常重要的。它們是有限的嗎？
Are they unique to Earth or could there be other environments, elsewhere in our Solar System or on exoplanets, for example? Organic molecules are present throughout the universe.
它們是地球獨有的嗎，還是可能也存在於其他環境之中，比如在太陽系的其他地方或者系外行星上？有機分子遍布整個宇宙。
But the presence of the basic ingredients of life may not in itself be enough for life to exist. To go from the inert to the living may require a very specific combination of environmental conditions that we're only just starting to piece together.
但是，生命基本成分的存在本身可能並不足以讓生命存在。從惰性到有生命存在可能需要一種非常特殊的環境條件組合，而我們只是剛剛開始進行拼湊。
Our planet clearly provided the conditions necessary for life to arise very early on. Liquid water has been present on Earth for 4.4 billion years.
我們的星球很早就為生命的誕生提供了必要的條件。液態水在地球上存在了44億年。
And the most ancient traces of life date from 3.8 billion years ago. On a geological timescale, life appeared very quickly.
最古老的生命痕跡可以追溯到38億年前。在地質時間尺度上，生命出現得非常快。
What then was this particular medium which allowed the first living organisms to appear so quickly? Biologist Purificación López-García here in Mexico, is studying the amazing adaptability of life in environments very similar to those of primitive Earth.
那麼，是什麼特殊的媒介使第一批生物如此迅速地出現呢？墨西哥的生物學家 Purificación López-García 正在研究生命在與原始地球環境非常相似的環境中驚人的適應性。
Wow, it's great! I thought the lake would be smaller. But it's pretty big.
哇哦，這太棒了！我原以為這個湖會小一些。但它相當大。
And deep. It's going to be hard to get down. Lovely!
而且很深。要下去會很困難。真不錯！
And it smells of sulphur. I love it! Shall we go?
它聞起來有硫磺的味道。我喜歡！我們走嗎？
Yes. Purificación and David Moreira are exploring the crater of the volcano El Chichón in Mexico.
好的。Purificación 和 David Moreira 正在探索墨西哥 El Chichon 火山的火山口。
Fumaroles, boiling cauldrons, hot mud and springs — the geothermal activity is evident everywhere here. Gas rising from the bowels of the Earth bubbles up through the acid lake.
火山噴氣孔、沸騰的汽鍋、熱泥漿和溫泉——地熱活動在這裡隨處可見。氣體從地球內部穿過酸湖冒出來。
The two biologists' first task is to measure the parameters of this extreme environment, before looking for signs of life. Is it hot?
這兩位生物學家的第一個任務是在尋找生命跡象之前，測量這種極端環境的參數。它熱嗎？
Really hot, yes. There we're up to 90,92… It's still going up. 94,95…96.7 degrees where it comes out.
是的，非常燙。現在是 90、92，還在上升……94、95、96.7度。
It must be seriously hot inside. If you ignore the plants at the edge of the craters, this is like some environments of primitive Earth, with lots of volcanic activity and hydrothermal activity.
裡面一定很熱。如果你忽略隕石坑邊緣的植物，這就像一些原始地球的環境，有很多火山活動和熱液活動。
Hydrothermal activity was a constant on primitive Earth. The same?
在原始地球上，熱液活動是恆定的。一樣的嗎？
Yes, 96.6. Shall we take a sample?
是的，96.6度。我們要不要取個樣？
A bit of sulphur. This hydrothermal environment is very similar to that in which life first appeared.
一點點硫磺。這種熱液環境與生命最初出現的環境非常相似。
And it doesn't take the two biologists long to find organisms which appear to thrive here. Beautiful! Great! We'll take a sample here too.
這兩位生物學家很快就找到了在這裡茁壯成長的生物。漂亮！太棒了！我們也要在這裡取個樣。
Despite these conditions which to us seem extreme, there's abundant microbial life here. The two scientists find and observe many varieties of bacteria organised in communities.
儘管這些條件在我們看來很極端，但這裡有豐富的微生物生命。這兩位科學家發現到並觀察了許多不同種類的細菌群落。
These organisms aren't primitive organisms. Yet, from the microbial diversity we find here and in other ecosystems, we can deduce the characteristics of the first living organisms.
這些生物不是原始生物。然而，從我們在這裡和其他生態系統中發現的微生物多樣性，我們可以推斷出最早的生物的特徵。
Studying environments like this volcanic crater, scientists can easily imagine the types of environments which were favourable to the formation of life on Earth. There's a lot of hot water vapour.
通過研究這樣的火山坑，科學家們可以很容易地想像出有利於地球上生命形成的環境類型。有很多熱水蒸汽。
We can hear the water but we can't see it. Shall we go to the lake?
我們能聽到水的聲音，但看不見它。我們去湖邊好嗎？
We'll get down over there. Four billion years ago, the chemistry of life may well have begun in small puddles swept by a backwash.
我們到那邊去。40億年前，生命的化學組成很可能開始於被反衝衝刷過的小水窪。
Many hypotheses about the origins of life suggest this, that there were tides leaving little lakes, small ponds, which let the organic molecules come together to maybe kick-start life. Maybe we needed both land and sea.
許多關於生命起源的假設都表明，潮汐會留下小湖泊、小池塘，讓有機分子聚在一起，那也許是生命開始的地方。也許我們需要陸地和海洋。
The big danger would have been too much water. With just a little bit more water, we'd have had deeper oceans, maybe tens of thousands of metres deeper, and we'd have had no land, just one big ocean, but no surface, no interaction, no possibility of environments favourable to life.
最大的危險是水太多了。只要再多一點點水，我們就會有更深的海洋，也許有幾萬米深，我們就不會有陸地，只有一個大海洋，但是沒有地面，沒有相互作用，沒有適合生命生存的環境的可能性。
We can wonder if the fact that Earth had just the right amount of water to have 70% oceans, continents, and an interaction was what made life possible. The ponds of hydrothermal springs provide an ideal environment in which the chemistry of life can get started: water, heat, and chemical elements rising from under the surface.
我們想知道，地球上有足夠數量的水，有70%的海洋和大陸以及相互作用，是否就是這些使生命成為可能。溫泉池為生命的化學反應提供了理想的環境：水、熱和化學元素從地表下上升。
Primitive Earth was definitely a chemistry lab, a "dirty" chemistry lab, with lots of components all mixed up, with a lot of changing of parameters and conditions. For several hundreds of millions of years, the molecules mixed together, rearranging themselves in all possible combinations, becoming ever more complex.
原始的地球無疑是一個化學實驗室，一個「骯髒的」化學實驗室，有很多成分都混合在一起，有很多參數和條件的變化。在數億年的時間裡，這些分子混合在一起，以各種可能的方式重新組合，變得越來越複雜。
For this chemistry to finally produce life, the chemical elements needed to be able to assemble in isolation from the outside environment. The cell membrane needed inventing.
要使這種化學物質最終產生生命，化學元素必須能夠在與外界環境隔絕的情況下進行組裝。細胞膜需要嘗試創新。
If at one point a bubble of grease enveloped these elements, then that was the first individual. And if it split into two, that was the first population.
如果在某一時刻有一團油脂包裹著這些元素，那麼這就是第一個個體。如果它一分為二，那就是第一個種群。
Life began. Having only just come into existence, the first lifeforms were still fragile, their only protection from the outside environment a thin membrane.
生命就此開始。最初的生命形式剛剛出現，仍然很脆弱，將它們與外部環境隔絕的唯一保護只有一層薄膜。
Yet they succeeded in developing their metabolism and specialising. Life could now diversify, trying out multiple forms.
然而，它們成功地發展出了自己的新陳代謝和專業化功能。生命現在可以多樣化發展，嘗試多種形式。
Life has diversified enormously, but from a single common ancestor. Maybe early on there were several hesitant beginnings of life, but only one survived.
生命已經非常多樣化了，但都來自同一個祖先。也許在生命的早期有過幾次在不同發展方向上的猶豫，但只有一個是最終選擇。
We know this because, despite the incredible diversity of living things, animals, plants, and the enormous variety and diversity of micro-organisms, we all have characteristics that we share. The same biochemical base, the same DNA as genetic material, and we're all based on the same proteins.
我們知道這一點是因為，儘管生物、動物、植物和微生物的多樣性令人難以置信，但我們都有共同的特徵。我們有同樣的生化基礎，有同樣的 DNA 作為遺傳物質，我們都依賴同樣的蛋白質而生存。
Everything that's in bacteria, fungus, birds, whales or plants is the same stuff. We're all related, from bacteria to the most beautiful giraffe.
細菌、真菌、鳥類、鯨魚或植物中的一切都是一樣的東西。從細菌到最漂亮的長頸鹿，我們都是親戚。
All inhabitants on Earth carry within them the traces of this shared ancient history. For we're all constructed from a limited number of identical basic ingredients.
地球上的所有居民都攜帶著這種共享的古代歷史的痕跡。因為我們都是由有限數量相同的基本成分構成的。
And yet, four billion years ago, other building blocks were available on primitive Earth. Meteorites came from bodies which broke up billions of years ago.
然而，40億年前，在原始的地球上也有其他的「建築材料」。隕石來自於數十億年前解體的天體。
And in these meteorites there were from 60 to 80 amino acids. We only use 20!
在這些隕石中有60到80個胺基酸。我們只用20個！
The first lifeforms chose these 20 amino acids. Why those?
最初的生命形式選擇了這20種胺基酸。為什麼是這些呢？
It's probably just a question of chance. You can very well imagine a world in which living creatures are made up of 28 amino acids, but not the same ones as us.
這可能只是個機會問題。你完全可以想像一個生物由28種胺基酸組成的世界，但這些胺基酸和我們不同。
It wouldn't produce the same lifeforms. They'd be very different.
它不會產生相同的生命形式。它們會非常不同。
Scientists come up against a serious problem when trying to work out how life first came into being. Four billion years of plate tectonics have obliterated any trace of the first organisms.
科學家在試圖弄清生命最初是如何形成的時候，遇到了一個嚴重的問題。40億年的板塊構造抹去了最初生物的任何痕跡。
So they have to look elsewhere, on a planet where conditions favourable to life did once exist, and where traces of this distant past may still remain. There's no plate tectonics on the surface of Mars, or at least it stopped very early there, which means that, at certain sites, its entire history has been preserved going back a very long time, up to 4 billion years.
因此，他們不得不尋找其他地方，尋找一個曾經存在有利生命條件的星球，那裡可能仍然保留著遠古時代的痕跡。火星表面沒有板塊構造，或者至少在很早的時候就停止了，這意味著，在某些地點，它的整個歷史被保存了很長一段時間，長達40億年。
There was certainly time for life to occur on Mars, before the planet lost its atmosphere, and any record of these beginnings could have very well been preserved under the surface. Mars had a youth very similar to Earth's, with liquid water, comets raining down, organic matter and so on, just like on Earth.
在火星失去大氣層之前，火星上肯定有生命存在的時間，而關於這些生命起源的任何記錄都可能很好地保存在火星表面之下。火星的年輕時期和地球非常相似，有液態水，彗星落下，有機物等等，和地球一樣。
With the same ingredients from space, there might have been the same beginnings of chemical changes which on Earth produced life. Maybe on Mars there were these first stages too, like making membranes, structures like that.
有了來自太空的相同成分，地球上產生生命的化學變化可能也有相同的開端。也許在火星上也有這樣的第一步，比如製造膜，這樣的結構。
We've studied the planet a lot, and we've realised that 3.5 to 4 billion years ago Mars had the conditions that could have supported the beginnings of life. We've found, with the Curiosity rover, which has been on Mars for 7 years now and is still investigating, that the crater it touched down in, which is 160 kilometres across, used to be a lake of fresh water, filled with fresh water.
我們對火星做了很多研究，發現35億到40億年前，火星具備了生命起源的條件。「好奇號」探測器已經在火星上呆了7年，目前仍在調查中，我們發現它著陸的隕石坑，直徑160公裡，曾經是一個淡水湖，充滿了淡水。
This water was present for hundreds of millions of years. So it's possible that life appeared in that crater.
這些水存在了數億年。所以隕石坑中可能有生命出現。
Exploring the former lakes of Mars, these scientists are hoping to answer one of the major questions of astronomy and biology. Is life a pretty ordinary phenomenon in the universe, popping up wherever conditions are favourable, or is it really a one-off phenomenon that we have practically no hope of finding anywhere else but on Earth?
這些科學家在探索火星的湖泊時，希望能回答一個天文學和生物學的主要問題。生命在宇宙中是一種非常普通的現象，只要有條件就會突然出現，還是只是一種我們除了在地球上幾乎沒有希望在其他地方找到的一次性現象？
This is the crucial question which the next missions to explore the red planet's arid surface will attempt to answer. Even though for the last forty years the history of the search for life on Mars has been one long series of disappointments.
這是下一個探索這顆紅色星球乾旱表面的任務將試圖回答的關鍵問題。儘管在過去的四十年裡，在火星上尋找生命的歷史一直是一連串的失望。
Almost every two years we hear "We've found evidence of life!" But we haven't, on Mars!
幾乎每兩年我們就會聽到「我們發現了生命的證據！」這種話。但在火星上我們並沒有發現什麼！
These disappointments began with Mariner 4 in 1965. As the probe got close to Mars, it sent back the first photographs of the surface… to the consternation of the scientific community.
這些失望始於1965年的「水手4號」。當探測器接近火星時，它發回了第一張火星表面的照片，使科學界大為震驚。
The photos showed a dry and desert-like planet. Then it was the Viking missions, the first time scientific probes actually touched down on Martian soil.
這些照片顯示出了一個乾燥的、類似沙漠的星球。之後是海盜號任務，這是第一次科學探測器真正登陸火星的土壤。
In 1976, the Viking probes looked for life with biological experiments, looking for life on the surface of Mars. The results were negatives.
1976年，海盜號探測器通過生物實驗尋找生命，在火星表面尋找生命。結果是否定的。
The Viking experiments were actually looking for life on Mars that'd be the same as on Earth. That's a total illusion.
維京人的實驗實際上是在火星上尋找和地球上一樣的生命。這完全是幻覺。
And it didn't work, it got nowhere. It was a huge disappointment.
但這沒有成功，沒有任何進展。這是一個巨大的失望。
As the 1980s dawned, not just the general public but scientists too were in thrall to the then dominant idea in both cinema and literature that life abounded beyond our planet. That was the first big shock, shaking the dominant paradigm of that time, which said that there was life everywhere, including on Mars.
隨著20世紀80年代的到來，不僅僅是普通大眾，科學家們也被當時在電影和文學中佔主導地位的觀點所束縛，即在我們的星球之外，生命也豐富多彩。這是第一次巨大的震動，動搖了當時的主流範式，即生命無處不在，包括火星上也是如此。
The failure of the Viking missions called for a total rethink of how we should tackle the question of extra-terrestrial life. Since mankind had been convinced for several centuries that there was life all over the universe and the Solar System, people seriously thought that Mars was the most likely to be favourable to life.
海盜號任務的失敗呼籲我們重新思考如何解決外星生命的問題。幾個世紀以來，人類一直確信整個宇宙和太陽系都有生命存在，所以人們很認真地認為火星是最適合生命存在的地方。
It took several setbacks in those experiments before people realised that this idea that there was life everywhere had run its course. It's only recently that space missions have showed that we should have a different approach in our missions to the planet Mars.
在那些實驗中經歷了幾次挫折之後，人們才意識到生命無處不在的觀點已經到了盡頭。直到最近，太空任務才表明，我們在火星任務中應該採用不同的方法。
The next exploratory missions to Mars won't be looking for life now, but rather the trace of life in the past. This is the objective of the ambitious European ExoMars mission with its mobile laboratory.
下一次火星探測任務將不是尋找現在的存在生命，而是尋找過去生命的蹤跡。這是雄心勃勃的歐洲 ExoMars 任務及其移動實驗室的目標。
We know Mars well enough now to look specifically for things that have been preserved, in the right context, in zones favourable to life. It is here in Turin that the gigantic 3D jigsaw puzzle of the European ExoMars is being assembled.
我們現在對火星非常了解，可以專門尋找那些在適宜的環境下、在適宜生命存在的地帶被保存下來的東西。在都靈，巨大的歐洲 ExoMars 3D 拼圖正在組裝之中。
It's a worthy challenge for the scientific community. From the control centre in Turin, Caroline Freyssinet will monitor the analyses of the Martian soil carried out by the automatic laboratory in the rover.
對科學界來說，這是一個有價值的挑戰。在都靈的控制中心，卡洛琳·弗雷西內(Caroline Freyssinet)將監測探測器上的自動實驗室對火星土壤的分析。
It's the first time a mission will be capable of analysing samples from beneath the surface of Mars. The surface is bombarded by radiation which destroys the material we're looking for, organic matter, which would be the possible residue of a lifeform.
這是第一次有能力分析火星表面下的樣本的任務。地表受到輻射的衝擊，破壞了我們正在尋找的物質——有機物，即可能是生命形式的殘留物。
Mars' atmosphere became too feeble to filter the solar radiation that is so harmful to life. By drilling down two metres, we can get to much better preserved environments, where it is more likely that the molecules we're looking for would be preserved.
火星的大氣層變得太脆弱，無法過濾對生命如此有害的太陽輻射。通過向下鑽兩米深，我們可以到達保存得更好的環境，在那裡我們尋找的分子更有可能被保存下來。
Looking for life on Mars is, in effect, looking for our own origins. On Earth we don't know how we went from chemistry to biology.
在火星上尋找生命，實際上就是尋找我們自己的起源。在地球上，我們不知道我們是如何從化學過渡到生物學的。
It's the missing link of exobiology, that passage from chemistry to biology. If, on Mars, through these experiments, we find organic matter, we can say that we're retracing the first stages of how life emerged on Earth.
這是外太空生物學中缺失的一環，從化學到生物學的過渡。如果在火星上，通過這些實驗，我們找到了有機物，我們就可以說我們在追溯地球上生命起源的最初階段。
Earth fortunately underwent a very different history from that of Mars. Our planet was able to hold on to its atmosphere and liquid water.
幸運的是，地球經歷了一段與火星非常不同的歷史。我們的星球能夠留住大氣層和液態水。
Life continued to evolve, inventing new forms. This white rock is testimony to an upheaval that occurred 2.5 billion years ago in the oceans, a development which changed the entire history of life on Earth, a planet-scale revolution brought about by micro-organisms.
生命繼續進化，創造新的形式。這塊白色的巖石是發生在25億年前海洋劇變的證據，這一變化改變了整個地球生命的歷史，是由微生物帶來的一場行星級別的革命。
It's beautiful. To me, this rock is the history of Earth, the history of biology.
它很美。對我來說，這塊巖石就是地球的歷史，生物的歷史。
It's evolution. It's the amazing ability to transform matter and energy.
是進化。是一種轉化物質和能量的神奇能力。
It's fantastic. We're the children of this type of micro-organism.
非常絕妙。我們是這種微生物的後代。
This is our parent, in a way. These aren't just any rocks that biologist Purificación López-García and her team are here to study.
在某種程度上，這就是我們的父母。生物學家 Purificacion Lopez-Garcia 和她的團隊來這裡研究的不僅僅是巖石。
These calcareous structures — the result of what was a brand-new process, using solar radiation as a source of energy — are stromatolites, constructed by complex microbial communities, in particular cyanobacteria. I'm surrounded by fossil stromatolites.
這些鈣質結構是疊層石，由複雜的微生物群落構成，特別是藍藻細菌。這是一個全新的過程，利用太陽輻射作為能量來源。我周圍都是疊層石化石。
This is a piece of a living stromatolite, that I've just chopped. You can see the colonies of green cyanobacteria.
這是一塊活的疊層石，我剛剛把它切碎。你可以看到綠色藍藻的菌落。
It's the typical colour of chlorophyll, the pigment essential for photosynthesis. This great innovation by cyanobacteria was their ability to manufacture their own food, sugars, from the three most abundant elements on primitive Earth; water, carbon dioxide and sunlight.
它是葉綠素的典型顏色，是光合作用所必需的色素。藍藻的這個偉大創新是他們能夠從原始地球上最豐富的三種元素中製造自己的食物和糖，這三種元素即水、二氧化碳和陽光。
This process, photosynthesis, also produces a calcareous deposit which surrounds and protects the cyanobacteria, allowing them to form colonies. Look.
這個過程，也就是光合作用，也會產生一種包圍和保護藍藻的鈣質沉積物，讓它們形成菌落。看。
A lovely piece! It's growing really…
很可愛！它成長得非常……
Really, really fast. We have at least… at least 100 micrometres of growth per year.
非常非常快。我們每年至少有100微米的增長。
Maybe even 200 to 250. That's wonderful.
甚至可能是200到250人。這很美妙。
We were happy this morning because we found colonisation systems we placed here five years ago now colonised by microbial communities which produce these minerals. Very quick growth.
今天早上我們很高興，因為我們發現了五年前我們放置在這裡的繁殖系統現在被生產這些礦物質的微生物群落佔據了。它們生長得非常快。
It's about a millimetre per year, which is huge. 2.4 billion years ago, cyanobacteria benefited from an unexpected asset to help them colonise and dominate Earth's ecosystem.
大約每年一毫米，這是個巨大的增長量。24億年前，藍藻從一項意想不到的資產中獲益，幫助它們在地球生態系統中殖民和統治。
Photosynthesis produced a waste product, oxygen, which was poisonous to the first organisms on Earth. This oxygen, released in great quantities into the atmosphere wreaked havoc on other primitive organisms, leaving the field clear for the cyanobacteria.
光合作用產生了一種「廢物」——氧氣，它對地球上最初的生物體來說是有毒的。這種大量釋放到大氣中的氧氣對其他原始生物體造成了破壞，為藍藻細菌留下了廣闊的繁殖空間。
As oxygen was toxic for many other organisms, they imposed themselves in certain niches. First they learnt to resist this toxic oxygen, and then they colonised this new, oxygen-filled environment, in the sunlight, everywhere, from oceans to lakes, to all sorts of surfaces on land.
由於氧氣對許多其他生物體是有毒的，它們就把自己強加在某些生態位上。首先它們學會了抵抗這種有毒的氧氣，然後它們就在這個充滿氧氣的新環境中繁殖，在陽光下，各處，從海洋到湖泊，到陸地上的各種地表。
The cyanobacteria became the most abundant organisms on Earth, and their massive presence changed our planet. The atmosphere now contained oxygen.
藍藻成為地球上最豐富的生物，它們的大量存在改變了我們的星球。大氣中現在是含有氧氣的。
And oxygen also provided life on Earth with a new protective barrier. High up in the atmosphere, ultraviolet radiation transformed oxygen into ozone and gave Earth a vital shield — the ozone layer.
氧氣也為地球上的生命提供了新的保護屏障。在大氣層的高處，紫外線輻射將氧氣轉化為臭氧，為地球提供了一個至關重要的屏障——臭氧層。
Earth's surface was now protected from harmful ultraviolet radiation, and new forms of life were free to evolve in the open air. When you see a picture of Earth, such as from a space station, you see how incredibly thin the protective atmosphere is, this thin film which was made by life itself over time.
地球表面現在已經免受有害的紫外線輻射，新的生命形式可以在露天環境下自由地進化。當你從太空站看到地球的照片時，你會看到保護氣層是多麼的薄，這種薄膜是由生命本身隨著時間的推移而形成的。
And you realise to what extent all these particularities were essential, not just for Earth, but for the life to which it is home. Thanks to the cyanobacteria, a fascinating self-perpetuating circle came into being.
你會意識到，所有這些特質無論在多大程度上都是至關重要的，不僅僅是對地球而言，對作為地球家園的生命而言也是如此。感謝藍藻，一個迷人的自我永恆的循環就此形成。
At first Earth helped foster the evolution of life, but then, with oxygen, it was life that changed Earth, making Earth increasingly welcoming to the evolution of life. Our planet started to look different, becoming a green planet, a planet the colour of chlorophyll.
起初，地球促進了生命的進化，但後來，有了氧氣，是生命改變了地球，使地球越來越歡迎生命的進化。我們的星球開始看起來不一樣了，變成了一個綠色的星球，一個像葉綠素一樣顏色的星球。
With oxygen's role in releasing energy, enabling the release of lots of energy through chemical reaction, it's more useful for animals, and probably led to the evolution of multicellular organisms. Multicellular organisms, then larger animals, could now evolve thanks to this new element, essential for keeping these increasingly complex biological machines running.
由於氧氣在釋放能量方面的作用，使其能夠通過化學反應釋放大量的能量，所以它對動物更有用，可能還導致了多細胞生物的進化。多虧了這個新元素，多細胞生物和更大的動物才得以進化，這個元素對維持這些日益複雜的生物機器運轉至關重要。
New features requiring a greater energy input, like muscles, a liver or a brain, could now form. Evolution shaped our planet and its diversity.
需要更多能量輸入的新特徵，如肌肉、肝臟或大腦，現在就可以形成了。進化塑造了我們的星球和它的多樣性。
Evolution and life on Earth are indissociable. I'm stunned by biological diversity.
進化和地球上的生命是不可分割的。我對生物的多樣性感到震驚。
Life is constantly evolving, producing not just the parrot but all these forms of animals and plants that we see here in this primary forest. But I also realise how hard this world can be.
生命在不斷進化，不僅產生了鸚鵡，還產生了我們在這片原始森林中看到的各種動植物。但我也意識到這個世界是多麼的艱難。
It's beautiful, but it's a world full of struggles between different types of organisms. I can see how Darwin came up with his theory of natural selection, having come to places like this, where you can see these selection mechanisms working all the time.
這是個美麗的世界，但也是一個充滿不同類型生物之間鬥爭的世界。我可以理解達爾文是如何提出他的自然選擇理論的，在這樣的地方，你可以看到這些選擇機制一直在運作。
Our ecosystem is the culmination of a long dialogue between life and the environment, a dialogue orchestrated by the rules of evolution. When individuals are almost identical, they'll be in varied circumstances, and in the population of these individuals, some will have a small particularity.
我們的生態系統是生命與環境長期對話的頂點，是由進化規則精心安排的對話。當個體幾乎完全相同時，他們會處在不同的環境中，在這些個體的群體中，有些會有一點特殊性。
And this particularity may give them a competitive advantage for getting food or reproducing. They'll reproduce faster and gradually supplant those that don't have the particularity.
這種特殊性可能會給它們在獲取食物或繁殖方面帶來競爭優勢。它們會繁殖得更快，逐漸取代那些沒有這種特殊性的物種。
It's the environment that has selected the individuals best adapted to the current circumstances. The environment itself was now modified by the biological activity of these individuals.
是環境選擇了最能適應當前環境的個體。環境本身現在被這些個體的生物活動所改變。
Evolution, in fact, is a constant back and forth between the environment and its inhabitants. There's no purposeful direction.
事實上，進化是環境和其居住者之間的一種不斷往復的過程。沒有明確的方向。
It's not a straight line making evolution progress from bacteria to human beings. It does go from bacteria to us, but also from bacteria to bacteria.
從細菌進化到人類並不是一條直線。確實是從細菌傳播到我們，但也從細菌傳播到細菌。
Evolution is a sort of fan going in every possible direction. Evolution explores what is biologically possible.
進化是向著所有可能方向呈扇形展開的。進化探索著生物上的可能。
We're in constant movement. And this is what has created something absolutely unique.
我們在不停地運動。這就是創造出絕對獨特的東西的原因。
This is the rich dynamic that has been driving Earth since its origins. Stimulated by the diversity of its environments and climates, life is permanently inventing new solutions.
這是豐富的動力，地球自地球起源開始就一直驅動著它。在環境和氣候多樣性的刺激下，生命不斷地創造新的解決方案。
From one continent to another, species evolve differently, coming up with new strategies. If we relaunched evolution since the origin of life, would we get the same result?
從一個大陸到另一個大陸，物種進化不同，有了新的策略。如果我們從生命起源開始重新開始進化，我們會得到同樣的結果嗎？
Probably not. They say history repeats itself, but it doesn't really.
可能不會。人們說歷史會重演，但事實並非如此。
Some things are repeated, but history is always different. It's the same with life.
有些事情是重複的，但歷史總是不同的。生命也是如此。
If we threw the dice again, it's unlikely we'd get the same animals and plants that we have today. Evolution on Earth is a coming together of the adaptations of genetics and the environment, an environment which is itself the result of a long succession of chance events.
如果我們再來一次，我們不可能得到和今天一樣的動物和植物。地球上的進化是基因和環境的適應結合在一起的產物，而環境本身就是一連串偶然事件的結果。
Chance multiplied by chance. It's all this chance which has made Earth unique.
機遇與機遇相疊加。正是這些機遇讓地球變得獨一無二。
And the ecosystems in which we find ourselves, snow, desert, sand or sea… we won't find them anywhere else. Earth's ecosystem is the result of a random process.
而我們所處的生態系統，雪、沙漠、沙子或海洋，我們在任何其他地方都找不到。地球的生態系統是一個隨機過程的結果。
The probability of evolution producing a similar result on another planet seems very weak. And yet, for the last 25 years, astronomers have discovered countless planets in our galaxy.
進化在另一個星球上產生類似結果的可能性似乎很低。然而，在過去的25年裡，天文學家在我們的星系中發現了無數的行星。
They are now quite certain that around most stars there are planets. The actual number of planets in the universe must be beyond our imagination.
他們現在相當確定，在大多數恆星的周圍都有行星。宇宙中行星的實際數目肯定超出了我們的想像。
This is the argument brought up to challenge this change of paradigm. There are billions of galaxies, all with billions of planets.
這是為挑戰這種範式的變化而提出的論點。即，有數十億個星系，所有星系都有數十億個行星。
That's true. But billions of billions isn't infinity.
這是真的。但數十億又數十億也並不是無限的。
There are billions of people, but we're all different. It's not about there being billions of galaxies, it's that, in probability terms, billions of billions may not be a big enough number for us to find an identical case.
世界上有幾十億人，但我們都是不同的。並不是說有幾十億個星系，而是說，從概率的角度來說，幾十億個星系也可能不足以讓我們找到一個和我們相同的情況。
In any case, if we do discover another lifeform, it'll be surprising and fundamentally different from life on Earth. I wouldn't expect to find a tree on another planet, or an ecosystem identical to this one.
無論如何，如果我們真的發現了另一種生命形式，那將是令人十分驚訝的，它與地球上的生命有著根本的不同。我不會指望在另一個星球上找到一棵樹，或一個與這個星球相同的生態系統。
If life has occurred on other planets, based on a similar chemistry, I'm not even sure there'd be animals and plants. Don't imagine we could find our environment on another planet.
如果其他行星上也有生命，基於類似的化學反應，我甚至不確定是否會有動物和植物。不要想像我們能在另一個星球上找到如我們現在所處的環境。
It's a complete illusion. Could there be a planet B?
這完全是一種幻覺。會有第二個這樣的行星嗎？
My answer is very harsh. There is no planet B.
我的答案很刺耳。沒有了。
And it's criminal to say there is. There's only one spaceship with Earth's ecosystem, and that's Earth.
而且說有是大錯特錯。有地球這般生態系統的宇宙飛船只有一艘，那就是地球。
There'll be no other. For around four billion years, Earth has been home to life of increasing diversity, constantly inventing new strategies to survive cataclysms or changes in the environment.
再沒有別的了。在大約40億年的時間裡，地球一直是生物多樣性不斷增加的家園，不斷發明新的策略來在大災難或環境變化中生存。
Life always seems to be on the front foot, as though determined to survive in one form or another. Yet today it seems that this beautiful machine, Earth's ecosystem, could well be stalling as a result of the depredations done to it by our own species.
生命似乎總是處於領先地位，似乎決心要以這樣或那樣的形式生存下去。然而今天，這個美麗的機器——地球的生態系統，似乎很可能因為我們人類對它的破壞而停止運轉。
We are part of this same biodiversity, this ecosystem. If we destroy it, then that's all part of this ecology, in a deep way, and we'll probably go extinct.
我們也是這個生物多樣性、這個生態系統的一部分。如果我們破壞了它，那麼就會破壞這整個生態系統，說得更重一點，我們可能會滅絕。
But we won't be the last to go. We'll go a long time before the bacteria.
但我們不會是最後一個離開的。我們的消失會比細菌早很久。
We're just a leaf at the end of a branch which is billions of years old, the same as all the bacteria, all the trees, all the plants and all the micro-organisms on the planet. We're just one more part of this biodiversity.
我們只是一個樹枝末端的葉子，它已經有幾十億年的歷史了，和地球上所有的細菌、所有的樹、所有的植物和所有的微生物一樣。我們只是這個生物多樣性的一部分。
Nothing more than that.
僅此而已。