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  • On April 15th, 1912, anUnsinkable shipnamed the Titanic hit an iceberg and came

    一九一二年四月十五日,名叫鐵達尼號,被稱作為「永不沉沒的船」撞上了冰山,

  • to rest nearly 4 kilometers beneath the surface.

    沈入四公里深的海底深處。

  • Light?

    有光線嗎?

  • None.

    沒有。

  • The temperature?

    溫度多少?

  • Two degrees Celsius.

    攝氏兩度。

  • Pressures?

    氣壓多少?

  • 5000 pounds per square inch.

    5000 磅每平方英寸。

  • But more than 100 years later, this watery graveyard is somehow teeming with life.

    但是過了一百年以後,這個水裡的墳場不知怎麼地充滿了生命。

  • Those strange icicle shapes covering the Titanic are full of microscopic organisms that thrive

    覆蓋在鐵達尼號上的那些奇怪冰柱狀上長滿了微生物,

  • in one of Earth's most inhospitable environments.

    這些微生物正在地球上最惡劣的環境下茁壯生長。

  • They can literally *eat metal* and someday soon, they'll leave nothing but a rusty

    它們真的可以吃金屬,而在將來的某一天,它們只會在原本船的地方留下

  • pile of powder where the ship once was.

    一堆生鏽的粉末。

  • These deep-sea microbes are extremophiles, one of countless organisms living hidden in

    這些深海微生物是嗜極生物,它們是居住在世界最極端的

  • Earth's most extreme habitats, adapted to conditions where, until recently, we figured

    棲息地裡無數個生命中的其中之一,它們適應了原本我們以為

  • life couldn't exist.

    不會有生命的環境。

  • Extremophiles have changed how we view life's possibilities on Earth.

    嗜極生物改變了我們對於生命的可能性的看法。

  • They hold clues to how life may have taken hold on this planet, and also give us hints

    它們身上有生命如何在這個星球上扎根的線索,也可以提示我們

  • about life's possibilities deep in space.

    關於生命在太空深處的可能。

  • Off the Galapagos islands, 2 kilometers underwater, Earth's mantle and the ocean directly meet,

    在加拉帕戈斯島下兩公里的深海處,地函和海交接的地方

  • creating strange, smoking vents with temperatures above 100˚C… yet home to ecosystems as

    會產生奇怪和會冒煙的熱泉噴口,它們的溫度超過一百度,但是它們和熱帶雨林一樣

  • rich as any rainforest.

    是非常多生態系的家。

  • At the base of this deep-sea food chain is a weird kind of single-celled life.

    在深海食物鏈的底層有一個奇怪的單細胞生物。

  • Archaea.

    古菌。

  • When it was discovered by Carl Woese, it completely redrew the tree of life.

    當它被 Carl Woese 發現的時候,生命之樹完全被重畫。

  • They look a lot like bacteriaprokaryotesbut Archaea have unique internal machinery.

    它們看起來很像單核細菌,但是古菌有獨特的生理系統。

  • And in Earth's most extreme habitats, we find them more often than any other life form.

    而且相較於其他生物,我們發現在地球上最極端的棲息地裡古菌最常被找到。

  • Organisms adapted to high temperatures, can grow above 120˚C, hot enough to disintegrate

    適應高溫的生物可以在高於一百二十度的環境下生長,這個溫度足夠分解

  • most cells' machinery.

    絕大多數細胞的機能。

  • The microbes at these deep sea vents have unique adaptations like specially wound DNA,

    生長在深海的微生物有特殊的適應,像是纏繞成不同形狀的 DNA

  • and putting extra bonds in their proteins to keep everything from melting.

    和在蛋白質上增加多餘的鍵以防止所有的東西融化。

  • And it's not just single-celled life.

    而且不止單細胞生物。

  • Larger organisms like tube worms and hairy crabs thrive in these super-hot ecosystems

    比較大的生物像是管蠕蟲和毛蟹也生長在這些超級熱的

  • too.

    生態系統裡。

  • This is a place completely devoid of light, where energy must instead be harvested from

    這個地方完全沒有陽光,所以能量必須從地殼噴口所產生的

  • hydrogen and sulfur gases bubbling from the tectonic vents.

    氫氣和硫磺中收集。

  • Not unlike conditions we expect to find on Jupiter's moon Europa, where the geologically

    不像是我們預期在木星的衛星「木衛二」上看到的那個樣子,活躍的

  • active interior creates pitch black oceans of liquid water beneath its icy surface.

    地質內部會在冰的底下製造黑色的液態水。

  • When it comes to pressure, we don't know what life's limits might be.

    以壓力來說,我們並不知道生命的極限在哪裡。

  • The deepest places probed on Earth, like the Mariana trench, are home to microbial life

    地球上偵測到最深的位置像是馬裏亞納群島是一些可以承受高壓的

  • able to withstand pressures more than a thousand times higher than we feel at Earth's surface.

    微生物的家,它們可以承受的氣壓是我們在地球表面上的幾千倍。

  • And when scientists exposed other microbes to *low* atmospheric pressures like those

    而且當科學家把其他的微生物也暴露在像是火星的那種低氣壓下,

  • on, say, Mars, many were likeno problem, this is fine”.

    很多微生物都覺得沒有大礙。

  • But there ARE a couple things it seems life can't do without.

    但是有幾個東西對生命來說是不可或缺的。

  • The universal needs for life are good ol' carbon and water.

    宇宙的萬物都需要好的氧氣和水。

  • Life is basically organized chemistry.

    生命基本上就是有組織的化學。

  • Inside every cell on Earth, the making and breaking of bonds, building cellular machinery,

    在地球上所有的細胞裡,鍵結的形成和破壞、細胞結構的建立、

  • copying DNA, even the membranes that keep a cell from spilling its gutsall depend

    DNA 的複製、甚至是防止胞器跑出細胞的細胞膜都仰賴

  • on liquid H2O.

    液態水。

  • But salty environments, frozen environments, or low-pressure atmospheres lack usable H2O,

    但是鹹的、冰凍的或是低氣壓的環境缺乏可以使用的水,

  • they're essentially as dry as deserts.

    它們基本上跟沙漠一樣乾。

  • Yet, in places like super-dry Antarctica, and deep in hidden caves, we find microbes,

    不過,我們在像是南極一樣很乾燥的地方和洞穴的底部都有找到微生物,

  • tucked away *inside* rocks and crystals, where they've carved out tiny water-filled pocket little

    它們隱藏在石頭和水晶裡面,它們會雕出細小的洞,這些洞裡充滿著水,像是

  • microscopic oases in deserts made of stone and salt.

    沙漠裡由石頭和鹽所製造出的小綠洲。

  • In places like Chile's Atacama desert, one of the driest places on Earth, microbes pluck

    在像是智利的阿塔卡馬沙漠,地球上其中一個最乾燥的地方裡,微生物會直接拿

  • water molecules right from the air, and make their own liquid shells.

    空氣中的水分子來製作一個液態外殼。

  • On a planet like Venus, where it's just too darn hot for water to remain liquid at

    在像是金星的星球上,當表面溫度已經太熱,水不可能維持液態的時候,

  • the surface--microbial life could be suspended in tiny droplets of water in the upper atmosphere.

    微生物可以懸浮在地表上層空氣中的小水滴中。

  • One of the biggest risks to life anywhere is dangerous radiation: UV, gamma rays, and

    不論在哪裡,生命其中一個最大的威脅是危險的輻射,例如紫外線、伽瑪射線和

  • X-rays, which can damage cells and mutate DNA.

    X 光,它們可以摧毀細胞和造成 DNA 突變。

  • We don't worry about it much here because our magnetic field protects us, but elsewhere

    因為磁場會保護我們所以我們不太擔心這些,但是在其他的地方

  • life would either be forced to shield itself underground or else figure out how to put

    生命會被迫於躲到地底下或是尋找一個

  • up with a daily dose of mutation.

    可以每天承受突變的方法。

  • Microbes seem to have this figured out too.

    微生物似乎已經找到了方法。

  • In places like Chernobyl, we've found bacteria that can withstand huge doses of radiation.

    在像是切爾諾貝利的地方,我們找到了可以經得住大量輻射的細菌。

  • Even cockroaches can handle at least 100 times more ionizing radiation than humans can, although

    甚至是蟑螂可以承受的游離輻射量都至少是人類的一百倍,儘管

  • this is surprising to no one.

    這已經不值得驚訝。

  • If these extremes seem harsh, it's probably because animals like us have a very narrow

    如果這些極端的環境在我們看來很嚴苛,這可能是因為像我們一樣的動物有著非常狹窄的

  • window of survival.

    生存區間。

  • Life has existed on Earth for more than 3 billion years, and it's flip-flopped from

    生命已經生活在地球上超過 30 億年了,而且地球已經在

  • super scorching to super snowball many times.

    極度炎熱和冰冷之間變換過無數次。

  • Our extremes may have been normal to Earth's earliest inhabitants.

    我們所認為惡劣的環境也許對早期棲居在地球的生物來說是正常的。

  • Even our oxygen-rich atmosphere would be considered extreme to some life forms.

    高氧的空氣甚至對某些生物來說也是惡劣的環境。

  • There's a good chance the first lifeforms were similar to what Woese discovered at those

    有很大的可能初始的生命跟 Woose 在加拉帕戈斯底下

  • boiling black smokers beneath the Galapagos.

    的深海熱泉中找到的很相似。

  • Understanding how life survives our extremes broadens our horizons for where we think life

    了解生命如何在惡劣的環境中生存會幫助我們更加了解生命

  • can exist--and tells us where to look beyond Earth.

    可以存在的地方,並告訴我們在地球以外可以關注的地方。

  • So far, we've only found life in one place, but if the odds of sharing this galaxy with

    目前為止,我們只在一個地方找到生命,但是如果與另一個星球分享這個銀河系

  • another living planet ever seem too extreme, just remember that life, uh, finds a way.

    的可能性似乎過於極端,你只要記得生命會自己找到出路。

  • Stay curious.

    保持好奇。

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