是的 这是我们的家 Yes, this is home.
地球 This is Earth.
很难找到我们熟悉的大陆是吗 Having trouble finding a familiar continent?
过去的地球是另外一个世界 The past is another planet.
地球曾是很多个不同世界 Actually, many.
我正站在大爆炸以后 I'm standing on the great expanse of time that has elapsed
广袤的时间长河中 为了看得清楚一点 since the Big Bang. In order to think about it,
我们把这一大段时间都压缩到了一年中 we've compressed it all into a single year.
按我们的宇宙年历来说 It's the early morning of December 23
现在是十二月二十三日的凌晨 on this Cosmic Calendar of ours,
也就是大约三亿五千年前 or about 350 million years ago,
我们的地球刚满四十亿岁 when our world was a mere four billion years old.
地球看上去如此不同 Earth looks so different.
你甚至可能都认不出这是地球 You might not even know the place.
恒星帮不了你 The stars wouldn't help you.
甚至当时的星座也与现在不同 Even the constellations would have been different back then.
再过一亿年 The dinosaurs were still
恐龙才会出现 more than 100 million years in the future.
没有鸟 没有花 There were no birds, no flowers.
甚至连空气也与现在不同 And the air was different, too.
地球大气中的氧气比任何时候都要多 The atmosphere had more oxygen than at any other time
不管是过去还是将来 in Earth's history, before or since.
这使得昆虫比现在长得更大 This allowed insects to grow much larger than they do today.
怎么会这样 How?
昆虫没有肺 Insects don't have lungs.
赋予生命的氧气通过气孔 Life-giving oxygen is taken in through openings
从它们的体外进入体内 in the outside of their bodies
并通过气管运输 and transported through a network of tubes.
如果昆虫太大 If an insect were too large,
在氧气到达内部器官以前 the outer reaches of these tubes would absorb all the oxygen
外层气管就会吸收掉所有氧气 before it could ever get to its internal organs.
但在石炭纪期间 But during the Carboniferous Period,
大气中的氧气几乎是现在的两倍 the atmosphere had almost twice the oxygen as today.
昆虫能长得更大 Insects could then grow much bigger
但却仍能吸入足够的氧气 and still get enough oxygen in their bodies.
这就是为什么这里的蜻蜓像老鹰一样大 That's why the dragonflies here are as big as eagles
千足虫跟鳄鱼一样大 and the millipedes the size of alligators.
所以 为什么那时有这么多氧气 So why was there so much oxygen back then?
是新生命产生了这么多氧气 It was produced by a new kind of life.
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宇宙
时空之旅
什么样的生命能让地球大气 What kind of life could've changed
产生如此剧烈的改变 the Earth's atmosphere so dramatically?
就是能通向天空的植物 Plants that could reach for the sky--
树 trees.
在它们争夺阳光的过程中 In their competition for sunlight,
树进化出了一种方式来抵抗重力 trees evolved a way to defy gravity.
在树出现以前 最高的植物 Before trees, the tallest vegetation was
只有齐腰高 only about waist-high.
然后奇妙的事发生了 And then something wonderful happened.
植物分子进化得更强壮而富有弹性 A plant molecule evolved that was both strong and flexible,
以支撑更重的重量 a material that could support a lot of weight,
并防止在风中被折断 yet bend in the wind without breaking.
木质素使这一切成为可能 Lignin made trees possible.
现在生命能够向上生长了 Now life could build upward.
这开启了一个全新的领域 And this opened a whole new territory,
高于地面的生命 a three-dimensional matrix
开启了一个三维空间 for communities far above the ground.
地球变成了树的海洋 Earth became the Planet of the Trees.
但是木质素也有缺点 But lignin had a downside:
它难以下咽 it was hard to swallow.
当自然的拆迁大队 真菌和细菌 When nature's demolition crew, the fungi and bacteria,
想要吞噬有木质素的植物时 tried to eat anything with lignin in it,
很不幸 它们消化不了 they got a really bad case of indigestion.
而白蚁在至少一亿年后 And termites wouldn't evolve
才会进化出来 for at least another 100 million years.
那些死去的树木怎么处理呢 What to do with all those dead trees?
真菌和细菌花了数百万年 It took the fungi and bacteria millions of years
才进化出生物化学方法来消耗它们 to evolve the biochemical means to consume them.
同时 树木持续生长 死亡 倒伏 Meanwhile, the trees just kept springing up, dying, falling over
它们被埋葬亿万年间积累的泥土中 and getting buried by the mud that built up over eons.
最终 几千亿棵树 Eventually, there were hundreds of billions of trees
被埋葬在了地球上 entombed in the Earth,
地球上到处都是被埋葬的树木 buried forests all over the Earth.
它们怎么可能带来危害呢 What possible harm could come from that?
新斯科舍的悬崖是另一种历法 This cliff in Nova Scotia is another kind of calendar.
它讲述了一个曾在这里繁荣昌盛的 It tells the story of that other world
另一个世界的故事 that once flourished right here.
这就是三亿年的树的 And this is the death mask
死亡面具 of that 300 million-year-old tree.
原来树木的细胞渐渐被矿物质替换 It was cast by minerals that replaced the original wood cell by cell
形成了化石 in other words, a fossil.
很久以前 树把它的有机分子 The tree surrendered its organic molecules
释放到了环境中 to the environment long ago,
释放碳和水 只有它的形状留存了下来 its carbon and water. Only its shape remains.
当树还活着的时候 它吸收二氧化碳 When this tree was alive, it took in carbon dioxide
和水 利用阳光 and water and used sunlight
把它们转化成充满能量的有机物 to turn them into energy-rich organic matter.
树把氧气作为废物排放出来 The tree gave off oxygen as a waste product.
树和其他的植物现在仍然如此 That's what trees and other plants still do.
植物死了会腐烂 When plants die, they decay,
腐烂反转了转化过程 and this reverses the transaction.
树的有机物与氧气结合 Their organic matter combines with oxygen
分解 and decomposes,
把二氧化碳又排放到空气中 putting carbon dioxide back into the air.
这个过程平衡了 This balances the books
地球大气中的化学物质 for the chemistry of Earth's atmosphere.
但是如果树木在它们腐烂以前被埋入地下 But if the trees are buried before they can decay,
会发生两件事 它们把碳 two things happen... they take the carbon
和太阳能储存起来 and stored solar energy with them
并将氧气释放 and leave the oxygen behind
在大气中逐渐积累 to build up in the atmosphere.
这就是大约三亿年前发生的事 That's what happened around 300 million years ago.
因为有氧气剩余 There was an oxygen surplus.
所以虫子才能长得这么大 That's how the bugs got so big.
那些被埋葬的碳发生了什么 And what became of all that buried carbon?
它们一直呆在那里 直到地球上发生了 It lay there for eons before dealing life on Earth
有史以来最具毁灭性的灾害 its most devastating blow of all time.
在这个行星有些地方 我们能走过时间 There are places on this planet where you can walk through time
阅读写在石头上的历史 and read the history written in the rocks.
新斯科舍的这个海滩就是其中一个 This beach in Nova Scotia is one of them.
每一层都是一页 Every layer is a page.
每一页都讲过洪水的故事 Each one tells the story of a flood,
在数百万年间 洪水发生了一次又一次 one after another, over millions of years.
一层层的洪水沉积物慢慢被埋葬 The layer cake of flood deposits was slowly buried
在高温高压作用下变成岩石 and turned into rock by heat and pressure.
形成山脉的作用力 The same forces that built mountains
又倾斜着抬起山脉 then tilted and uplifted them, along
带出了地下埋藏的化石群 with the entombed fossil forest.
新的岩层总是堆积在 The newer layers were always
旧的岩层上 deposited on top of the older ones.
每一页都按照正确的顺序 All the pages are in the correct order,
见证了在数百万年中 bearing witness to what happened here
这里发生了什么 over millions of years.
那边的岩层是更遥远的过去 Back that way lies the more distant past.
我每走一步 And with every step I take,
就是向现在移动了一千年 I move about 1,000 years closer to the present
离开三亿年前的世界 and away from the world of 300 million years ago.
五千万年以后在那里 50 million years later lies that way.
这是二叠纪结束的开始 This was the beginning of the end of the Permian world,
一场前所未有的屠杀 an event of unequalled carnage.
二叠纪是生命之树断枝纪念馆中 The Permian is the darkest corridor in this memorial
最黑暗的走廊 to the broken branches on the Tree of Life--
灭绝大厅 the Halls of Extinction.
死亡从未离得如此之近 Death has never come so close
在后来的两亿五千万年中 to reigning supreme on this world
主宰了这个世界 in the quarter billion years since.
在现在的西伯利亚 The eruptions, in what is now Siberia,
火山喷发持续了好多年 lasted for hundreds of thousands of years.
火山喷出的岩浆淹没了几百万平方千米 The lava flooded and buried more than a million square miles.
在历史长河中 其他火山喷发 This event dwarfs any volcanic eruption
都相形见绌 in historical times.
灭绝大厅
大量的二氧化碳从岩融裂隙中 Huge quantities of carbon dioxide came pouring
喷涌出来 out of the volcanic fissures.
这种温室气体使得气候变暖 This greenhouse gas warmed the climate.
在石炭纪早期 And this is where the long-buried forests
被长期埋葬的森林再次登场 of the earlier Carboniferous Period reenter the story.
在中间的五千万年里 During the intervening 50 million years,
那些树变成了巨大的煤炭储存 those trees had turned into immense deposits of coal,
随着这一切的发生 and as it happened,
世界上最大的煤炭储藏之一 one of the world's largest accumulations of coal
就埋藏在西伯利亚 was buried right there in Siberia.
火山岩浆的高温炙烤着煤炭 The heat from the lava baked the coal,
使甲烷和富硫气体涌出地面 driving methane and sulfur-rich gases out of the ground.
这些气体有毒且含有放射性灰烬微粒 They were laden with toxic and radioactive ash particles--
煤烟 coal smoke.
这种古怪的混合物污染了大气 This witch's brew polluted the atmosphere
彻底打破了地球的气候平衡 and radically destabilized Earth's climate.
硫酸烟雾挡住了阳光 A sulfuric acid haze blocked incoming sunlight
使得行星变得黑暗 and darkened the planet.
全球温度骤然下降到了冰点以下 Global temperatures plummeted to subfreezing.
在火山喷发的间歇 During lulls in the eruptions,
酸雾落到地面 the acid haze fell back to the surface.
但是留下了二氧化碳 But the carbon dioxide remained
在大气层中积累造成全球变暖 and built up in the atmosphere to cause global warming.
多年的严寒 Years of frigid cold
与令人窒息的高温交替 alternating with millennia of stifling heat
使得不断减少的植物和动物彻底灭绝 battered a dwindling population of plants and animals.
它们没有机会 They had no chance
适应气候的剧烈波动 to adapt to the drastic swings in climate.
随着全球持续变暖 As the global warming continued,
表面和下层的水 the surface and the bottom waters
慢慢混合 提高了 slowly mixed, raising the temperature
曾经寒冷的海底温度 of the once-frigid depths of the sea floor.
冻结在沉积物中的 Methane-rich ices
富含甲烷的冰开始融化 that had been frozen in the sediments began to melt.
甲烷气体涌出表面 Newly liberated methane gas made its way to the surface
进入大气 and into the atmosphere.
甲烷吸收的热量远远多于 Methane traps heat far more efficiently
二氧化碳 than carbon dioxide,
所以气候变得更热了 so the climate got even hotter.
甲烷还破坏了 And the methane also destroyed
平流层中的臭氧层 the ozone layer in the stratosphere.
这层保护生物不受致命的紫外线伤害的 The natural sunscreen that protects life from deadly ultraviolet rays
天然屏障被侵蚀 was eaten away.
世界大洋的循环系统停止 The circulatory system of the world ocean shut down.
这些死水变得缺少氧气 These stagnant waters became oxygen-starved,
几乎杀死了海洋中所有的鱼 killing almost all the fish in the sea.
但有一种生物在这种恶劣环境中活跃起来 But one kind of life flourished in this brutal environment...
一种细菌 它的代谢废物 bacteria that produced deadly hydrogen sulfide gas
正是致命的硫化氢气体 as a waste product.
那是最后一根稻草 That was the last straw.
毒气杀死了几乎所有陆地上剩下的 The poison gas killed almost all the remaining plants
植物和动物 and animals on the land.
这就是大灭绝 This was the Great Dying.
地球上的生命曾经差点被彻底消灭 The closest life on Earth has ever come to annihilation.
十分之九的物种灭亡了 Nine in ten of all species perished.
生物需要很长时间去恢复 It took a long time for life to bounce back.
在几百万年中 地球都可以被称之为 For a few million years, Earth could have been called
死亡星球 the Planet of the Dead.
我们是那勉强存活的 We are descended from one of the few species
少数物种之一的后人 that managed to squeak by.
因为它们的努力忍耐 You are human and alive at this very moment
此刻才有人类生存 because they managed to endure,
在最险恶的时期 conveying their DNA through one of the most treacherous periods
它们把基因传了下来 in the history of life.
这座山完全由生命组成 This mountain was made entirely by life.
生命又重新繁荣在那二叠纪的光辉岁月里 The life that flourished back in the glory days of the Permian,
虽然历经磨难 before all hell broke loose.
这是640千米长的 This is part of the 400 mile-long
瓜达卢普山脉的一部分 Guadalupe Mountain chain
它横跨德克萨斯州和新墨西哥州 that runs through Texas and New Mexico.
它是世界上最大的化石礁 It's the world's largest fossil reef.
这一切曾是一片广阔的内海 All this was once a great inland sea.
礁石在数百万年间繁荣生长 The reef flourished and grew for millions of years,
也是许多海绵动物 绿藻 and was home to multitudes of sponges, green algae,
和小到看不见的动物的栖身之地 and animals too small to see.
当这些生物死亡后 When these creatures died,
它们沉入底部 被埋进泥沙中 they sank to the bottom and were buried in the silt.
经过数百万年 Over millions of years,
它们的残骸转变成了石油和天然气 their remains were converted into oil and gas.
最终 内海淤积 礁石也死掉了 Eventually, the basin silted in and the reef died.
然后这座海中鬼镇被埋在了 This marine ghost town was then buried
地表两千米之下 a mile beneath the surface.
后来 构造力把礁石抬升到 Later, tectonic forces lifted the skeletal reef
海平面以上 随着时间流逝 high above sea level, where it was eroded and sculpted
它不断被风雨侵蚀雕刻着 over eons by wind and rain.
想象一下这个地方 Just imagine what this place looked like
两亿七千五百万年前的样子 275 million years ago,
那时它还是个充满活力的热带内海 when it was a vibrant, tropical inland sea,
中间散落着点点小岛 dotted with islands
充满了生命的活力 and brimming with life.
一直到大约两亿两千万年前 Until about 220 million years ago,
新英格兰和北非还相邻 New England and North Africa were next-door neighbors.
还没有大西洋这回事 There was no such thing as the Atlantic Ocean.
那些在中心的蓝色指状物 它们是湖泊 Those thin blue fingers at the center-- they were lakes.
它们是超大陆裂开和地球上的生命 They were the first outward signs that the supercontinent
会经历又一次巨变的 was splitting apart and that life on Earth
第一个外在标志 was due for another big shake-up.
一百万年以后 湖泊变成了狭长的海湾 A million years later, the lakes became a long bay,
后来成了大西洋 which would grow into the Atlantic Ocean.
地表上这些显著的变化 These profound changes at the surface
仅仅是在地球深处上演的好戏 were merely symptoms of a drama that was unfolding far beneath,
露出的迹象而已 in the depths of the Earth.
到我们出现的时候 By the time we got here,
全球剧变的痕迹已经被埋葬在 the telltale traces of global upheaval were buried
深蓝海洋的底部了 at the bottom of the deep blue sea.
我们完全不知道地球过去的狂野故事 We were completely cut off from the great story of Earth's violent past--
健忘的种族想要知道 a species of amnesiacs trying to find out
我们是谁 在我们醒来以前 who we were and what happened
发生了什么 before we awakened.
1570年亚伯拉罕·奥特柳斯创作了 In 1570, Abraham Ortelius created the first
第一本现代世界地图集 回顾了 modern world atlas, reflecting on the discoveries
过去八十年的发现 of the previous 80 years--
探索的黄金时代 the Golden Age of Exploration.
没等墨迹干透 Before the ink was dry,
奥特柳斯就开始重新审视他的作品 Ortelius stepped back from his masterpiece
他变成了第一个 and became the first of many to notice the striking
注意到大西洋两旁的 puzzle-piece fit between the continents
大陆相互吻合的人 on either side of the Atlantic.
他后来写道 经过了地震和洪水 He later wrote that the Americas were torn away
美洲从欧洲和非洲中分离了出来 from Europe and Africa by earthquakes and floods.
但是奥特柳斯的观察 But Ortelius's observation
比起下两个世纪的发现 remained nothing more than a hunch
仅仅称得上预感而已 for the next couple of centuries...
直到二十世纪早期 until an early 20th century
一位德国天文学家和气象学家 German astronomer and meteorologist
收集了证据 amassed the evidence
才为其建立起了系统的理论 to build the scientific case for it.
阿尔弗雷德·魏格纳在一战期间完成了初稿 Alfred Wegener had been drafted during the First World War,
但是不久以后他就受了伤 but was wounded soon after.
他在战地医院恢复的时候 As he recovered in a field hospital,
他在科学文献中搜寻地球的过往 he scoured scientific literature for clues to the Earth's past.
多年以前 Years before,
魏格纳在大学图书馆 Wegener had happened upon an intriguing paper
偶然发现一篇有趣的论文 in the stacks of his university library.
论文中提到大西洋的两岸 It puzzled Wegener
曾发现同一种已灭绝的蕨类植物化石 that fossils of the same species of a now-extinct fern
这使魏格纳感到困惑 were reported to be found on both sides of the Atlantic.
更令人感到好奇的是在两个大陆上 Even more curious were the discoveries of fossils
发现了同一种恐龙的化石 of the same dinosaurs on both continents.
在二十世纪早期 In the early 20th century,
地质学家猜想大陆间曾有一座陆桥 geologists explained how life crossed the oceans
这就解释了生物是如何跨越海洋的 by imagining that land bridges had once existed between them.
他们认为很久以前这些陆桥 It was thought that these land bridges gradually disintegrated
在海浪的冲刷下逐渐分解消失 and vanished beneath the waves long ago.
但有一个证据使魏格纳确信 But there was one piece of evidence that convinced Wegener
这种公认的科学观点肯定是错的 that the prevailing scientific view must be wrong...
这个证据就是地球本身 the Earth itself.
一座山脉为什么会跨过大洋 Why would a mountain range cross the oceanic divide
在另一块大陆上继续呢 to continue on another continent?
为什么你在巴西和南非的岩层中 And why would you find the same unique pattern
找到相同的特有结构 in the layers of rocks in both Brazil and South Africa?
此外 And another thing...
在什么样的情形下 热带植物会大量生长在 under what circumstances could tropical plants have flourished
冰天雪地的北极 in the frozen wastes of the Arctic?
魏格纳的结论是 Wegener concluded that
这些疑问只有一个合理的解释 there was only one logical solution to this puzzle...
地球上曾经只有一块超大陆 There had once been a single supercontinent on Earth.
他将其命名为盘古大陆 He named it Pangaea.
所以魏格纳成了科学界家喻户晓的人物对吗 So Wegener becomes the toast of the scientific world, right?
也不是 Not exactly.
大多数地质学家都嘲笑魏格纳的 Most geologists ridiculed Wegener's hypothesis
大陆漂移假说 of continental drift.
他们更倾向于用他们虚构的天然陆桥 They preferred their imaginary natural land bridges
来否定魏格纳的证据 to explain away Wegener's evidence.
他们问 大陆是怎么通过 How, they asked, could a continent plow through
洋底的坚石的 the solid rock of the ocean floor?
魏格纳拿不出令人信服的证据 Wegener had no convincing answer.
他变成了科学界的笑柄 He became the laughingstock of the field;
成了科学会议中的下等公民 a pariah at scientific conferences.
尽管如此 魏格纳还继续坚持他的看法 Despite this, Wegener continued to fight for his ideas,
进行了大胆的调查以收集证据 conducting daring research expeditions to gather evidence.
在某一个调查中 他发现他的同事们 On one of these, he learned that colleagues were
被困在了冰盖 并且没有食物 trapped on an ice cap without food.
在他完成任务回去的路上 On his way back from the mission,
他在暴风雪中迷路了 he became lost in a blizzard.
在他五十岁生日的一两天后 A day or two after his 50th birthday,
他失踪了 he disappeared,
但他永远也不会知道 不久以后 never knowing that, in time,
他会被证明是正确的 并被看作是 he would be vindicated and come to be viewed
历史上最伟大的地质学家之一 as one of the greatest geologists in history.
科学家们也是人 Scientists are human.
我们也有盲点和偏见 We have our blind spots and prejudices.
科学的目的 Science is a mechanism
在于找出它们 designed to ferret them out.
问题是 对于科学的核心价值 Problem is, we aren't always faithful
我们不总是忠实的 to the core values of science.
在这方面玛丽·撒普感触最深 Few people knew this better than Marie Tharp.
1952年 玛丽忍受着地质学部的 It's 1952, and Marie is patiently enduring the slights
同事对她的轻视 of her fellow members of the geology department.
跟他们在一起 她的地质学和数学学历 Her degrees in geology and mathematics
变得无足轻重 count for little with them.
布鲁斯·希曾 一名来自爱荷华州的研究生 Bruce Heezen, a graduate student from Iowa,
刚从漫长的考察中回来 has just returned from a lengthy expedition
考察旨在用声呐绘制洋底的地图 to map the ocean floor using sonar.
你要对这些做点什么吗 Will you do something with these?
布鲁斯 看 Bruce, look.
它们都聚集到了一起 It's-- it's all come together.
这是贯穿大西洋底部的 There's this giant rift valley
巨大裂谷 that runs through the bottom of the Atlantic.
天哪 玛丽 算了吧 Aw, geez, Marie, come on.
又是这些无稽之谈 This is just more girl talk.
你在这找的麻烦还不够多吗 You're not in enough trouble with everyone here already?
这听上去很像大陆漂移说 This sounds too much like continental drift.
你想像魏格纳一样结束吗 You want to end up like Wegener?
但玛丽不会被劝阻 But Marie would not be dissuaded.
多年以后 当玛丽和布鲁斯 Years later, when Marie and Bruce placed a map of
把海洋震中地图放在她的海底地图上 oceanic earthquake epicenters on a light table
在看片台上观看时 over her seafloor map,
地震正好落在 the earthquakes fell right along
裂谷处 the rift valley.
这就是魏格纳的大陆漂移学说的 This was the smoking gun
确凿证据 for Wegener's moving continents.
希曾现在知道 Heezen now knew
玛丽一直是正确的 that Marie had been right all along.
同时 他们绘制了第一张真正的地球地图 Together, they created the first true map of the Earth,
也包含洋底的地图 including the ocean floor.
我们终于能阅读 We were at last ready to read
地球的自传了 the autobiography of the Earth.
让我们乘着想象号飞船 Let's take the Ship of the Imagination...
去到只有很少人 to a part of the world that has been off-limits
知道的地方 to all but a few of us.
地球的三分之二 Two-thirds of the Earth
都在超过300米的水下 lies beneath more than 1,000 feet of water.
广阔且大部分未被探索 It's a vast and largely unexplored frontier.
每个人都知道阿尔卑斯山和落基山 Everybody knows the Alps and the Rockies,
但是世界上许多令人叹为观止的山脉 but some of the world's most amazing mountain ranges
都不人所知 are hidden from view.
在一千米下面 我们到了一个 Below 1,000 meters, we enter a world
没有阳光的世界 where there is no sunlight.
隐藏在黑暗中 一个充满了奇迹的世界 Hidden in the darkness, a world of wonders.
这是世界上最长的海底山脉 This is the longest submarine mountain range in the world,
大西洋中脊 the Atlantic Mid-Ocean Ridge.
它就像棒球的接缝一样环绕着地球 It wraps around our globe like the seam on a baseball.
地球的过去与现在不同 The past is another planet,
但大多数人连现在的地球都不了解 but most of us don't really know this one.
我们看不到水中的山 We don't see the mountains for the water.
玛丽·撒普是第一个想象出这个世界的人 This is the world that Marie Tharp was the first to imagine.
山脉的最高峰 The highest peaks of the ridge
比洋底高四千米 rise over four kilometers above the ocean floor.
这里也有连绵的山脉和峡谷 There are sprawling mountain ranges and canyons, too.
我们现在进入了马里亚纳沟 We've now entered the Marianas Trench,
地球上最深的峡谷 the deepest canyon on Earth,
有十几千米深 more than ten kilometers deep.
构造力将海床推倒了相邻的大陆板块下 It formed when tectonic forces pushed the seabed
形成了峡谷 under the adjoining continental plate.
潜入这里的人 More people have walked on the Moon
比上过月球的人还少 than have ever been down here.
这里的压力高达一吨每平方厘米 The pressure here is a crushing eight tons per square inch.
潜到这么深 Being this deep in the ocean
就像有五十架大型喷气式客机压在你身上 is like having 50 jumbo jets stacked on top of you.
然而即使在这里 也有生命存在 Yet even here, life has taken hold.
阳光无法穿透这么深的海 The fact that sunlight can't penetrate the deep ocean
不代表这里没有光 doesn't mean there isn't light down here.
许多水下的物种都会在黑暗中发光 Many underwater species glow in the dark,
通过一种叫做生物发光的过程 through a process called bioluminescence.
我们作为陆生哺乳动物 Our long history as land mammals,
长期生活在阳光下 denizens of the sunlit world,
使得我们没有想到进化 hasn't prepared us for the amazing variety of life
在深海中能创造出如此多样的生命 that evolution has crafted in the deep oceans.
因为这里没有阳光 Since there's no sunlight down here,
所以没有光合作用 there's no photosynthesis.
那就意味着没有植物供给养分 That means there are no plants to feed on,
然而 在这个漆黑的世界里 and yet, even here, in a world of permanent midnight,
却有一条欣欣向荣的食物链 there's a thriving food chain.
它开始于一个叫化能合成的过程 It begins with a process called chemosynthesis.
这些微小的生物学会了 These microscopic creatures have learned to eat
食用从热泉喷出的东西 what's pouring out of that vent...
一种叫做硫化氢的有毒化合物 a noxious compound called hydrogen sulfide.
那些厚重的黑烟提供了 That thick black smoke provides the chemical energy
使生命存在的化学能 that makes life possible here.
小的甲壳纲动物食用细菌 Tiny crustaceans eat the bacteria,
而大一点的动物食用甲壳纲动物 and the larger animals eat the crustaceans.
总有一天 在未来的地球 One day, on some future Earth,
这些山会浮出水面 these mountains could very well end up above the water.
构造力仍然在塑造我们的行星 Tectonic forces continue to shape our planet.
未来的地球也会与现在不同 The future is also another planet.
就是这样的一个火山 It was a volcano like this one
在数百万年前创造了夏威夷群岛 that created the Hawaiian islands millions of years ago.
我们生活在地壳上面 We live on the crust of
地壳内部如同沸腾的大锅 a seething cauldron.
在我们的行星中心有一个铁核 At the center of our planet, there's an iron core.
处在液态铁壳中 It's nested inside of a larger, liquid iron shell.
被叫做地幔的部分覆盖 Wrapped over this is the part called the mantle.
它由岩石组成 但又热又粘 It's rocky but hot and viscous.
就像火炉上炖着的一盆汤 Like a pot of soup cooking on a stove,
地幔一直在不停翻滚 the mantle is churning.
是什么让它一直运动 What keeps it moving?
两个原因 地球形成时剩余的热量 Two things... the heat left over from Earth's formation,
和地核的放射性元素的衰变 and the decay of radioactive elements in the core.
而我们每个人熟知 And this outer layer-- the crust,
并生活的地壳 where you and me and everyone we know lives--
仅仅像苹果皮一样薄 is only as thick as the skin on an apple.
地幔拖着它上面覆盖的地壳 The mantle drags the solid overlying crust along with it.
地壳能够承受是因为它又冷又硬 The crust resists because it's cool and rigid.
有时候 它会到强度极限 From time to time, it reaches the breaking point.
这种情况发生的时候 地震就来了 When that happens, the Earth quakes.
这并不是因为有人行为不端 It's not because somebody misbehaved
被惩罚 and is being punished.
它起因于随机的力量 It's due to random forces
这种力量取决于自然法则 that are governed by the laws of nature.
我们认为地球很稳定的感觉是一种错觉 Our sense of the stability of the Earth is an illusion
因为我们的生命太短暂了 due to the shortness of our lives.
如果我们能在地球的时间尺度上看看地球 If we could watch our planet on its own timescale,
在数百万年间发生的巨大变化 in which big changes take millions of years to play out,
我们会把它看成一个动态的有机体 we would see it as the dynamic organism it really is.
这是大概两亿年前 This is the world of the late Triassic period
三叠纪后期的世界 about 200 million years ago.
那个小家伙 That little guy?
那是我们遥远祖先中的一个 It's one of our distant ancestors.
他就生活在新泽西州的纽瓦克市 He lived in Newark, New Jersey.
无论你走到地球的哪里 Wherever you walk on Earth...
消失的世界都埋葬在你脚下 lost worlds lie buried beneath your feet.
五千万或一亿年以前 50 or 100 million years ago,
即使是地表上最普通的地方 even the most seemingly ordinary places
都发生了史诗般的变化 have been the scene of epic change.
这些岩壁就是 These Palisades are
盘古大陆解体的纪念碑 a monument to the breakup of the supercontinent Pangaea.
火山连续喷发 创造了这些悬崖 The sequence of volcanic eruptions that made these cliffs
也导致了下一个大灭绝 also led to the next mass extinction--
也就是结束三叠纪的大灭绝 the one that ended the Triassic world.
但是一个物种的灾难性灭绝 But a catastrophic extinction event for one species
是另一个物种的绝佳机会 is a golden opportunity for another.
三叠纪的灭绝给一个 The Triassic extinctions offered one group
已经出现一段时间的物种 that had been around for a while
提供了登上中央舞台的机会 the chance to take center stage.
恐龙称霸了 The dinosaurs had a good, long run
长达一亿七千万年 for 170 million years.
那时候印度还是个岛 Back then, India was an island.
它以每年十厘米的速度慢慢往北移动 It crept northward at the pace of a few inches per year
虽然很慢但最终与亚洲会合 on its slow but inexorable rendezvous with Asia.
然后 地球表面下的熔岩再一次喷发 Then, once again, the molten rock beneath Earth's surface
淹没了印度西部的大部分地区 burst forth and flooded a huge area of western India.
但致命一击 The knockout punch
完全没有预兆地出现了 literally came out of the blue.
很少有体重大于45千克的动物 Few animals larger than a hundred pounds
在晚白垩纪的这场大灾难中存活了下来 survived the catastrophes of the late Cretaceous.
尘雾使地球在几个月内都处于黑暗寒冷中 The dust cloud brought night and cold to the surface for months.
恐龙被冻死饿死了 The dinosaurs froze and starved to death.
但是一些小的生物 But there were small creatures
存活了下来 who took shelter in the Earth.
当它们出现时 And when they emerged...
它们发现原来猎食它们的 they found that the monsters who had hunted
恐怖怪兽不见了 and terrorized them were gone.
地球变成了哺乳动物的世界 The Earth was becoming the Planet of the Mammals.
地球继续不断变化着 And the Earth continued its ceaseless changing.
这里曾是寸草不生的沙漠 This was once a desert where nothing could grow.
有着260万平方千米的沙子和盐 It was a million square miles of sand and salt,
比地球上现在任何环境都恶劣 far more hostile than any environment on Earth today.
白天的温度高的可以烤面包 Daytime temperatures were hot enough to bake bread.
而且处在海平面1.5千米以下 And it was more than a mile below sea level,
所以大气压 so the atmospheric pressure
比现在高50% was about 50% higher than what we're used to.
难以想象 It would be hard to think
这个行星上还有过更糟的环境 of a more unpromising environment on this planet.
但是五百五十万年以前 Yet this was the basin of the Mediterranean
这里是地中海盆地 five and a half million years ago,
然后它就变成了大海 before it became a sea.
地球从来没有停止过移动 The Earth never stops moving for long.
深盆地西部的 The natural dam at the western end
天然水坝倒塌了 of the deep basin gave way,
可能是因为地震 probably due to earthquakes.
洪水也开始泛滥 And the deluge began.
汹涌的洪水在一年以内 The torrential waters rushed in at a rate 40,000 times greater
以尼亚加拉瀑布四万倍的速度涌来 than Niagara Falls, turning a vast desert
把大片沙漠 into the Mediterranean Sea...
变成了地中海 in less than a year.
那时没有人 There were as yet no humans
见证这场巨大的洪水 to witness this enormous flood,
也没人感叹它创造出的美丽 nor to admire the beauty it created.
同时在地球的另一端 Meanwhile, half a world away,
一条广阔的海峡把北美和南美分割开来 a broad channel separated North and South America...
使得海流能从大西洋 allowing ocean currents to flow
流进太平洋 from the Atlantic into the Pacific Ocean.
构造力渐渐地 Tectonic forces gradually brought
把这两块大陆合并到一起 封闭了海峡 these two continents together, closing the channel
创造了了巴拿马地峡 and creating the Isthmus of Panama.
这重组了世界的洋流循环 This reorganized the worldwide pattern of ocean currents,
也影响了全球气候 which, in turn, affected the global climate.
在非洲 曾经的绿色森林 In Africa, the lush green forest canopy
变成了一片荒芜 gave way to a sparser landscape.
一些擅长在树上生活的物种 Some species that were highly specialized for life in the trees
走向灭绝 became extinct.
但是有一些物种 But the generalists, the ones that could find a way
不管生活给予它们什么 to make a living no matter what life threw at them,
它们都能适应并进化 endured and evolved.
我们的祖先就曾进入地下 Our ancestors had once burrowed deep in the ground
来躲避地面上的食肉动物 to avoid predators who stalked the surface.
但是恐龙灭绝以后 But when the dinosaurs perished,
它们开始在白天出来活动 they emerged into the daylight,
许多年后 在树上 and over the eons, made new lives
创造出了新生命 in the branches of the trees.
它们发达的对生拇指和脚趾 They developed opposable thumbs and toes
可以让它们从一棵树荡到另一棵树 for swinging from branch to branch,
穿过宽广的树冠 across the broad canopy of treetops,
就能找到它们需要的 where all their needs were fulfilled.
它们也能直立行走 但仅限短距离 They could also walk upright, but only for short distances.
四周有这么多树 它们不必走太远 With so many trees around, they didn't have to go very far.
然而变冷以后 But then it got colder,
树变得稀疏起来 and the trees thinned out,
广阔的大草原出现了 我们的祖先 broad grasslands sprang up, and our ancestors
不得不穿过草原来寻找食物 were forced to traverse them in search of food.
在热带草原上生活 You needed a totally different skill set
你需要完全不同的技能 to make it on the savanna.
从前 In the old days,
你能高高坐在树枝上 you could sit perched on your tree branch
在安全距离观察大型猫科动物 and watch the big cats from a safe distance.
现在你也置身于同样危险的境地 Now you were playing on the same dangerous field.
只有那些进化出在必要时候 The survivors were those who evolved the ability
用后肢长距离行走 to walk great distances on their hind legs
并且能跑的才会幸存下来 and to run when necessary.
这改变了它们 This changed the way
看世界的方式 they looked at the world.
手和胳膊不再用于行走 Hands and arms were no longer tied up with walking.
它们可以自由采集食物 捡起棍棒和骨头 They were free to gather food and pick up sticks and bones.
这些可以用为武器和工具 These could be used as weapons and tools.
试想一下 Think of it...
地球另一端的一小块土地的 A change in the topography of a small piece of land
地形变化改变了洋流 half a world away reroutes ocean currents.
非洲变得又冷又干 Africa grows colder and drier.
大部分树都无法适应新的气候 Most of the trees can't withstand the new climate.
那些在树里生活的灵长类 The primates who lived in them
不得不寻找新的住所 很快 have to seek other homes, and before you know it,
它们就学会了用工具重建家园 they're using tools to remake the planet.
地球决定着人类命运 The Earth has shaped the course of human destiny,
但遥远世界的无形引力也是如此 but so has the invisible pull of distant worlds.
行星用我们没有想到的方式 The planets have influenced our lives,
影响着我们的生活 but not in the way you think.
金星的引力 The gravitational pull of Venus--
小却距离近 small but close--
而木星的引力 遥远但却力量巨大 and that of Jupiter-- distant but massive--
将地轴倾斜 tilted the Earth's axis this way and that...
并非常轻微地扭曲了轨道的形状 and ever so slightly tweaked the shape of its orbit.
这周期性地改变了 This periodically altered
落在北极冰盖边缘的 the amount of sunlight
阳光的多少 falling on the edge of the northern ice cap.
有时它使那里的夏天更冷 Sometimes it made the summers there colder,
冰川每年都 and the glaciers advanced southward
向南移动 from one year to the next,
刮削摩擦 grinding and scraping,
压碎路上的一切障碍 and crushing everything in their path.
我们称之为冰河时代 That's what we call an ice age.
其他时候 地轴和轨道的改变 At other times, changes in Earth's axis and orbit
使得北极的夏天更温暖 made the Arctic summers warmer.
融化的冰盖开始退去 And the melting glaciers began to retreat.
想象一下我们的祖先为了在这种气候巨变中 Imagine how resourceful our ancestors had to be
存活下来是多么机智 in order to survive these radical changes in climate.
每个冰河时期 With each glacial period,
冰川增多 海洋减少 the ice sheets grow at the expense of the oceans;
世界海平面下降了约120米 the world sea level falls by more than 400 feet,
在大陆边缘 uncovering wide areas of land
大量陆地露出水面 along the edges of the continents.
一万五千年到两万五千年以前 15 to 25,000 years ago,
冰川后退的时候 there was a period when the ice receded,
陆桥暂时显露出来 exposing a temporary land bridge.
去往地球另一端的通道打开了 The gateway to the other half of the planet swings open.
流浪者们穿过陆桥 Bands of wanderers crossed the land bridge
到了北美和再南一点的地方 to North America and parts south.
大约一万年前 气候和海平面的 About 10,000 years ago, the manic swings
强烈波动暂停了 of the climate and sea levels came to a stop.
新的气候温和的时代开始了 A new and gentler climate age began.
也就是我们现在生活的时代 It's the one we live in now.
随着大量冰川融化 When the great ice sheets melted,
海平面上升到了现在的高度 the sea rose to its present height
而且河水从高地上带来了淤泥 and the rivers carried silt from the highlands
当它们到达大海时 to build great delta plains
就会形成大片三角洲平原 where they met the sea.
在那些土地肥沃的地方 On those fertile plains,
我们学会了一种新的生活方式 we learned a new way of life...
我们学会了种植食物来养活自己 how to grow things, to feed ourselves and more.
对我们大部分人来说 For most of us, this meant an end
这意味着数百万年流浪的结束 to a million years of wandering.
行星间的相互作用 The way the planets tug at each other,
地球表面的移动 the way the skin of the Earth moves,
那些变化对气候 the way those motions affect climate
和生命智力演化的影响 and the evolution of life and intelligence--
它们结合在一起 they all combined to give us the means
使得三角洲里的淤泥 to turn the mud of those river deltas
变成了最初的文明 into the first civilizations.
没有什么比得上间冰期 There's nothing like an interglacial period,
冰河时代中的温和间歇时期 one of those balmy intermissions in an ice age.
好消息是这个时期 And the great news is that this one is due to last
还要持续五万年 for another 50,000 years.
这对人类再好不过 What a break for our kind.
只有一个问题 Just one problem.
我们好像在不停地燃烧那些 We can't seem to stop burning up all those
从石炭纪就被埋在地里的树 buried trees from way back in the Carboniferous Age,
就是煤炭 in the form of coal;
还有古代浮游生物的遗骸 and the remains of ancient plankton,
也就是油和天然气 in the form of oil and gas.
如果我们可以停止燃烧 If we could,
从气候方面考虑我们就大功告成了 we'd be home free, climate-wise.
然而 我们却在以气候大灾难后 Instead, we're dumping carbon dioxide into the atmosphere
从未有过的速度 at a rate the Earth hasn't seen
源源不断地往大气中排放二氧化碳 since the great climate catastrophes of the past,
而气候大灾难导致了大灭绝 the ones that led to mass extinctions.
我们好像没法停止燃烧燃料 We just can't seem to break our addiction to the kinds of fuel
这会给我们带来恐龙时代时的气候 that'll bring back a climate last seen by the dinosaurs;
这种气候会淹没沿海城市 对我们的 a climate that will drown our coastal cities and wreak havoc
环境和生存能力造成严重破坏 on the environment and our ability to feed ourselves.
太阳的光辉始终照耀着我们 All the while, the glorious sun
太阳能是免费的能源 pours immaculate, free energy down upon us;
取之不尽 用之不竭 more than we will ever need.
为什么我们不能总结前人一代代 Why can't we summon the ingenuity and courage
传下来的智慧和勇气 of the generations that came before us?
恐龙无法预见小行星的到来 The dinosaurs never saw that asteroid coming.
而我们有什么借口 What's our excuse?
在灭绝大厅 There's a corridor
有一条走廊 in the Halls of Extinction that is, right now,
空旷 没有任何标记 empty and unmarked.
地球的自传仍在书写 The autobiography of the Earth is still being written.
我们的故事有可能终结在那里 There's a chance that the end of our story lies in there.
恭喜你 Congratulations.
你活了下来 You're alive.
在我们和这个世界最初的生命之间 There's an unbroken thread that stretches across
有一条完整的线 more than three billion years
跨越三十多亿年 that connects us to the first life
将我们连接起来 that ever touched this world.
想象一下我们无数的祖先 Think of how tough, resourceful and lucky
是多么的坚强机智和幸运 all of our countless ancestors must have been
才能生存了这么久 to survive long enough
将生命的讯息 to pass on the message of life to the next
一代一代 and the next...
传递了下来 and the next generation,
历经亿万代生命 hundreds of millions of times...
直到传递给我们 before it came to us.
有太多河要跨过 There were so many rivers to cross,
沿途有太多危险 so many hazards along the way.
食肉动物 饥饿 疾病 Predators, starvation, disease,
计算错误 漫长的冬天 miscalculation, long winters,
干旱 洪水 暴力 drought, flood and violence.
更不必说从我们的星球自身突发的巨变 Not to mention the occasional upheavals that erupted from within our planet
还有来自太空的飞来横祸 and the apocalyptic bolts that come from the blue.
不管我们在哪出生 No matter where we hail from
父母是谁 or who our parents were,
我们都是惊天大灾难中的幸存者的后代 we are descended from the hearty survivors of unimaginable catastrophes.
我们每一个人都是最长最危险的 Each of us is a runner in the longest and most dangerous
接力赛中的选手 relay race there ever was,
现在 我们抓住了我们手中的接力棒 and at this moment, we hold the baton in our hands.
过去地球与现在完全不同 The past is another planet.
未来也会是这样 And so is the future.
有些地质学家认为 Some 250 million years from now,
从现在起的两亿五千万年中 many geologists think that the lands of the Earth
地球的大陆会再一次合并 will be united once again.
所有这些美景将会消失 All this beauty will have vanished
我们现在的地球 and the Earth of our moment in time
也会成为消失的世界中的一员 will take its place among the lost worlds.
板块构造的巨大的内部动力 The great internal engine of plate tectonics
不在乎是否存在生命 is indifferent to life,
就像地球轨道和倾角的微小变化 as are the small changes in the Earth's orbit and tilt
以及与横冲直撞的小行星 and the occasional collisions
带来的偶然碰撞一样 with little worlds on rogue orbits.
这些力量不理会数十亿年来 These processes have no notion of what has been going on
在我们的地球表面发生了什么 over billions of years on our planet's surface.
它们并不在乎 They do not care.
地球是太阳最小的行星之一 Each of us is a tiny being
我们这些小生命在这颗渺小行星的表面上生活 riding on the outermost skin of one of the smaller planets
绕着太阳转了几十圈 for a few dozen trips around the local star.
地球上活得最久的物种 The things that live the longest on Earth
寿命不过地球年龄的百万分之一 endure for only about a millionth of the age of our planet.
所以 一个生命 So, of course, the individual organisms
看不到沧海桑田 see nothing of the overall pattern.
变化的大陆 Of changing continents...
气候 climate...
演化 evolution.
我们对起源的点滴了解 That we understand even a little of our origins
就是人类洞察力和勇气的伟大胜利之一 is one of the great triumphs of human insight and courage.
我们是谁 我们为什么会在这里 Who we are and why we are here can only be glimpsed
答案只能靠凑齐全景的碎片才能一瞥 by piecing together something of the full picture,
这些问题一定包含了无限的时间 which must encompass eons of time...
成千上万物种 millions of species...
以及无数个世界 and a multitude of worlds.
从这种观点来说 In this perspective, it's not surprising
我们是个谜这件事也就不足为奇了 that we're a mystery to ourselves and that,
尽管我们明显很自负 despite our manifest pretension,
但我们还远非我们小小家园的主人 we are far from being masters of our own little house.
这条新走廊的纪元 This new corridors no name above the entrance
还没定名 我们也不知道 to designate its epoch, and we don't yet know
哪些灭绝的物种会被挂在墙上留作纪念 which failed species will be memorialized within its walls.
这里发生了什么 什么方式 或大或小 What happens here, in countless ways, both large and small,
都由我们书写 is being written by us.
现在开始 Right now.