动物的末日（2009）

The eruption will go on for weeks,
抛到空中的碎屑足以填满大峡谷
throwing enough debris into the air, to fill the grand canyon.
燃烧中的岩石导致了野火熊熊燃烧
Smoldering chunks of rock ignite massive wildfires,
助长了正在上方形成的大黑云
adding to the paul that's forming overhead.
火山气体加上火山灰
The combination of the volcanic gases and the ash
会让天空的色彩变得异常鲜艳
would have made the sky very colored.
会形成鲜明橘红色的云
Vivid oranges and reds
还有火山灰形成的乌云 它会完全把阳光遮住
along with this dark veil of ash, that would diminish the sunlight all together.
不论在地球上的哪个地方 任何动物都会被影响到
You'd feel the effects no matter where you stood on the planet.
火山灰像雨一样落到世界各地
The ash rains down worldwide,
没有生物能够逃出这个超现实的新天空
there's no escaping the surreal new sky.
在几个星期到几个月之内
In an order of weeks to months,
大部分火山灰已经从大气层落下
most of the Ash will fall out of the atmosphere.
但是渗透到同温层里的火山灰可以停留在那里好几年
However gases that penetrate into the Earth's stratosphere can stay there for years.
整个地球都被一片暗淡无光的云层笼罩着
The whole planet is shrouded in bloom,
这种状况预示了还有更糟糕的事情要发生
an omen of even worse things to come.
几十万年以来 整个地球就是一个温室
For hundreds of thousands of years, Earth has been a global greenhouse,
把来自太阳光的热量留下来 替地表加温
trapping solar energy and heating the surface.
但是现在 火山灰等气体把太阳光又折射回去
But now, the volcanic gases deflect the sun's rays.
这个地狱最终开始冻结
Hell is about to freeze over.
现在天气突然变得寒冷
But all of a sudden now we get the cold,
我们的热带世界开始变得越来越冷
we have a tropical world the starts getting colder and colder and colder.
像这样的双重打击
And is that really one-two punch
就造成了泥盆纪时期的大灭绝
that makes up this Devonian mass extinction.
我们应该称其为泥盆纪大灭绝
We should call the Devonian Mass Extinctions.
对吃尽苦头的提塔利克鱼来说
For the suffering Tiktaaliks,
冰冷的河道变成了坟墓
the icy water ways become a tomb.
它们的数量正在逐渐减少
Their population slowly dwindles,
直到最后只剩下一条
until in the end, there's but one left,
然后这个关键物种就永远消失了
and then this pivotal species is gone forever.
提塔利克鱼是被公认为最伟大的脊椎动物祖先之一
Tiktaalik is justly regarded as one of the great vertebrate pioneers,
因为这种动物真的替我们铺了路
and since that here's an animal which really paves the way.
它们就是那时候的我们
It is us, us way back in time.
但是提塔利克鱼在那种环境下活不了多久
But Tiktaalik doesn't survive very long in this type of world,
我们要感激提塔利克鱼
the reason to Tiktaalik is just really loud
因为它们进化出了其它能存活下来的物种
and it gives rise to other species, which do better.
提塔利克鱼只是个垫脚石
Tiktaalik is but a stepping stone,
一个短暂存在的踏脚石
a short-lived stepping stone.
距离大灭绝发生已经过去了150万年
It is now 1.5 million years after the extinction began.
火山冬天已经过去了
The volcanic winter leaves,
超级地幔柱也终于燃尽了
and finally the super-plume burns out.
但是世界的面貌已经彻底改变
But the world will never be the same.
至少有70%物种就此从地球上消失
At least 70% of all species have perished.
海洋曾经聚集了无数生命与活力
Where once the oceans were a kaleidoscope of life and energy.
现在变得灰蒙蒙 空荡荡的
Now, they are empty and gray.
我们很容易认为大灭绝只会影响大型动物
It is easy for us to think mass extinction only affects large animals,
但其实最大的受害者往往是小动物
but in reality those that suffer the most are usually small.
在这场大灾难里 构成珊瑚礁的生物大批死亡
In this catastrophe, the organisms that form coral reefs are slaughtered.
它们曾经是构成整个繁华海洋都市的基础
They used to be the foundation for bustling cities,
现在它们已经彻底消失了
now they are simply gone.
在灾难到来前 海洋世界最繁华的时候
You got from a situation where had its maximum extent,
珊瑚礁的外露面♥积♥将近500万平方公里
reefs were exposed over the course of about 5 million square kilometers.
大灾难发生后 已经减少到只有1000平方公里左右
And those are reduced down to about 1,000 square kilometers at its maximum extent,
这对珊瑚礁的生态圈来说是一个巨大的损失
just a huge depletion of reef community.
除了珊瑚礁 最原始的无颚鱼类也绝种了
Along with the reefs, jaw-less fish, the most primitive of all are extinct.
邓氏鱼和艾登堡鱼母等盾皮鱼类很快也会消失
Armored fish like Dunkleosteus and Materpiscis will soon disappear.
几百万年来 经历了大灭绝的生还者
For millions of years, the extinctions beleaguered survivors
在这个条件恶劣的世界里为生存而努力奋斗着
struggle just to get by in this inhospitable world.
地球即将命悬一线 快要成为没有生命的行星了
Earth is perilously close, to becoming a lifeless planet.
但是还有一线希望
But all is not lost.
曾经助长大灭绝的植物
Trees, which one's contributed to the mass extinction,
现在正在帮助地球恢复元气
now help bring the planet back to life.
它们每年给大气层增添越来越多的氧气
Each year, they had more and more oxygen to the atmosphere.
气温也慢慢地稳定下来
Temperature stabilized.
气候也回来了 生命再度变得多元化
The seasons return, and once again, life diversified.
这时候形成的沼泽地成为了孕育生命进化的摇篮
The swamps of this time are the incubators for life's next great leap.
这跟我们人类的演变有着千丝万缕的联♥系♥
One we humans have a personal stake in.
超级地幔柱的喷发已经过去了一千万年
It is now ten million years after the superplume strike.
在现在如今为宾夕法尼亚州地区的一个沼泽里
In a shallow swamp, in what is now Pennsylvania,
一群沟鳞鱼正在寻找食物碎屑
a school of Bothriolepis scavenge for food.
这些奇怪的鱼类是少数存活下来的幸运儿
This strange fish is one of the lucky few to survive.
它们栖息在世界各地不同的环境中
They lived in many different environments all over the world,
这样就增加了它们的生存机率
improving their odds of survival.
但是它们还不知道的是 一群机灵的掠食者已经盯上了它们
But little do they know an agile predator has them in its sights.
它看起来很像提塔利克鱼 但是提塔利克鱼早已绝种
It almost looks like Tiktaalik, but Tiktaalik is long extinct.
其实这种鱼是提塔利克鱼的近亲
In fact, this is one of Tiktaalik's descendants.
它们跟我们人类的进化有着密切的关系
A critical link to the evolution of humankind.
它们就是五英尺长的鱼石螈
The five foot long, Ichthyostega.
鱼石螈很有意思
Ichthyostega is very interesting,
因为这种动物是所有化石记录里第一个有实际记载的案例
in the sense that this animal represents one of the first documented cases in the fossil record,
显示出它有脊椎动物的四肢 还有能够辨认的手指和脚趾
where we have a vertebrate with recognizable digits in its limbs.
我们不是很了解鱼石螈的前肢
The hand of Ichthyostega is not known,
但是我们却很了解它们的后肢
but the hind limbs are very well known.
有意思的是它的脚趾不是五只
And interestingly, there is not five digits,
而是七只
but there are seven.
它们的祖先提塔利克鱼用鱼鳃和肺部呼吸
Its ancestor Tiktaalik used both gills and lungs for respiration.
而鱼石螈就只用肺部呼吸
Ichthyostega only uses lungs,
它们离开水面时 有较结实的胸腔骨支撑着身体
a sturdier rib-cage supports its body when out of water,
从而减轻了肺部所承受的压力
relieving pressure on the lungs.
这意味着鱼石螈的呼吸要比提塔利克鱼要深得多
That means Ichthyostega can draw much deeper breaths than Tiktaalik.
就像现代的鲸鱼或海豚一样
Like a modern-day whale or dolphin,
在发动攻击前它们先到水面上做深呼吸
it gulps air at the surface before launching its attack.
你可以想象一下 在一个纷繁杂乱的沼泽中
If you think about it in a very tangled swamp,
下面有很多植物和树枝时 后肢就起到了关键性的作用
a lot of vegetation material down and sticks, legs are really useful,
你可以用后肢穿过树枝枯叶和其它一些东西
you can pull yourself through branches and dead leaves and material.
在水下活动时 四肢很有用
They're very useful for underwater appendages.
鱼石螈不论在水里 还是在陆地上都很自在
But Ichthyostega is as comfortable out of water as it is in it.
鱼石螈可以离开水面这点毋庸置疑
Ichthyostega certainly could get out,
但它们能不能把肚子抬起来 还有很大的争论
whether it could lift the self off its belly as there's a big debate about this,
它们的肩胛骨能承受多大力量 它们的前肢强不强壮
about this how strong were the shoulder gills, how strong were the four legs.
但它们是能支撑起自己身体动物的祖先
But it is the ancestor that does give rise to animals that could hold themselves up,
它们是第一批真正的两栖动物
these first true amphibians.
从地球最可怕灾难的废墟里
From the ashes of one of Earth's most horrific disasters,
生命以非比寻常的方式逐渐恢复过来
life has made an extraordinary comeback,
并达到了一个新的里程碑
and reached a new evolutionary milestone.
地球核心深处仍在持续不断地燃烧
The Earth's core continues to burn.
另一个超级地幔柱会随时会爆发 攻击我们的地球
At any moment, another superplume could assault our world.
如果真是这样的话 悲剧将会再度上演
And if it does, armageddon will return.