种出个地球（1）

you realise this place is a metaphor for something much bigger,
是地球的一个缩影
for the planet, really.
是人类与植物间关系的一个缩影
And for our relationship with plants
我们正是靠光合作用才得以延续生命
through photosynthesis to keep life going.
早期的地球就像我之前那房♥间
The early Earth was like my chamber.
起初它的氧气稀薄 但随着时间推移
It was transformed from a world with very little oxygen
氧气开始变得充足
to a world rich in oxygen.
至此 氧气有了新的用途
And all that oxygen began to do something else.
它在平流层之下创造了臭氧层
High in the stratosphere, it created ozone.
臭氧层就像保护毯包围着地球
This was a protective blanket which enveloped the Earth
阻止了太阳的有害紫外线辐射
and blocked most of the sun's dangerous UV rays.
这意味着地球史上第一次
It meant that for the first time in the planet's history,
植物终于能生存于大♥陆♥
plants could move on to the land.
这是历史性的一大进步
But it was no small step.
在水中生活亿万年后
If you'd been protected by water for billions of years
转而生存于陆地上 必然引发冲击
then the move to the land was going to be a rude shock.
然而在4亿多年前
Yet over 400 million years ago,
植物终究实现了这一质的飞跃
plants finally made that leap.
出乎意料 对于这些开拓者最有力的证明
Surprisingly, the best evidence for these pioneers
并非来自地球上其他国家
doesn't come from some exotic corner of our planet,
它们就在英国本土
but from Britain.
这里是苏格兰东北部
I've come to just outside the village of Rhynie
莱尼村庄的野外 我来拜访这面石墙
in northeast Scotland to see this - a stone wall.
它当然不是一面普通的石墙
But not just any stone wall, of course.
对我来说
For me,
这是科学史上最为重要的一面石墙
this is the most important stone wall in the history of science.
追溯到4亿1千万年前
Back 410 million years ago,
苏格兰位于赤道正南方
Scotland was located well south of the equato
跟现在的景象大相径庭
and looked like another world.
地热泉水沸溢而出
Hot springs and geysers
流经地区地表多石且贫瘠
boiled out across a rocky and barren landscape.
但同时有些事情正在发生
But something else was happening,
科学家们在这面石墙上
as scientists discovered when they came across
发现了一些奇特的痕迹
some curious markings in this wall.
这是其中一块 快看
This is one of them. Look at this.
这些奇怪的带状条纹
You see these really strange elongated shapes here.
一开始科学家并不知道这是什么
The first people just didn't really know what they were.
起初他们以为这是某种熔岩
They thought maybe, at first, it was some kind of lava.
但凑近一看
But when they looked really closely,
尤其是当将它切割抛光时
especially when they got it cut and polished,
岩石样貌顷刻变得栩栩如生
this rock literally came alive.
看看这上面这些黑色纹理
Because you can see these dark features here,
他们这才意识到 这些都是生物遗迹
they realised that this was something that was once living.
它们活着的时候就是这副模样
And when they were alive, this is what they looked like.
这是几厘米高的阿格莱蕨类
Just a few centimetres tall, they're called Aglaophyton.
光秃秃的枝干顶端长着球状物
Bulbous shapes on the end of naked stems.
在出现叶子和根系之前
A time before leaves or roots,
这些奇形怪状的生物
yet somehow these bizarre life forms
竟然沿着水边存活了下来
survived along the water's edge.
地质学家在苏格兰当地发现的
What geologists had found right here in Scotland
正是最早开始进化的先驱
were some of the earliest pioneering plants
来开拓陆地上的栖息之地
to make that giant leap, to colonise the land.
几乎是同一时期
And around this time,
沿着水体边缘一带
all along the margins of lakes and rivers,
所有原始植物都开始上岸
primitive plants were coming ashore.
若从太空遥望地球 这是第一次
For the first time when viewed from space,
能观察到陆地上开始有了生物
the land began to look alive.
地球极端恶劣的环境
The beginning of a transformation
开始向欣欣向荣的生态发展
from hostile world to fertile Earth.
但这并不是植物的全面着陆
Yet this wasn't a full-scale invasion.
只是一个小小立足点
Just a toehold.
植物仍需生长在水体边界
Plants were still tied to the water's edge,
无法向内陆扩展
unable to head inland
渗入荒芜多石的地表
and penetrate the harsh, rocky surface.
但这一切将很快改变
But all this was about to change.
植物进化出了有效解决方法
Plants evolved an inspired solution to the problem,
进化出了一个收集水分和养料的绝妙办法
a brilliant device for collecting water and nutrients
进化出了一个前所未有的部分
and something that they never really had before.
那就是根系
Roots.
柬埔寨
Cambodia.
12世纪建于塔普伦的寺庙
The 12th-century temple here at Ta Prohm
实属文化奇观
is a wonder of civilisation,
同时也是自然界的奇迹
but it's also a wonder of the natural world.
尽管这些无花果的根系
Although the roots of these strangler figs
不同于原始植物进化的根系
are very different from the first ones to evolve,
却是证明了植被
it's a superb place to reveal
如何靠根系进军内陆的绝佳场所
how roots allowed plants to invade inland.
根系潜藏着巨大能量
Roots are hugely powerful.
看这根多惹人爱
I mean, I love this one.
它奋力向顶部延伸
Look at it prising its way into that roof,
凸显整个构造
just lifting that whole structure up.
再往下延伸
And then boring down here,
穿透这些石块后便再也没有出现
through these stone blocks and then disappearing.
多少个世纪里 它所施加的都是极小力道
Just tiny pressures exerted over decades of centuries.
但聚少成多 最终汇成了惊人的力量
Add these up and you get phenomenal strength.
每平方厘米有10千克的压强
A pressure of up to 10kg per square cm.
大约4亿年前 出现了原始根系
Around 400 million years ago, the first roots appeared...
从而使植被能粉碎地表岩石
...and gave plants the ability to smash up the rocky planet.
同时创造出陆上生物的重要元素
And this created a vital ingredient for life on land.
当细微的岩石颗粒
When the tiny, broken-up fragments of rock
与枯萎植物混杂在一起时
get mixed up with dead plant material,
就形成了储存水分的理想场所
it ends up as this ideal environment for storing water.
我们叫它"土壤"
An environment that we call soil.
现在 地球表面40%都是土壤
Today, soil covers 40% of the planet's land.
它的形成过程非常缓慢
It takes a long time to form,
一千年才能形成两厘米
1,000 years to make just 2cm of soil.
但它是植被存活的重要因素
But it's essential for plant life,
正如4亿年前的当时
just as it was back then.
因为原始无叶植被正是因此
Because the primitive leafless plants
可以离开水边了
could now break free from the water's edge.
根系及其创造的土壤
Roots, and the soil they created,
使得植物所向披靡
made plants unstoppable...
首次推动它们向内陆开拓的进程
...allowing them to colonise inland for the first time.
这次大举入侵
An invasion that would have
是一次改变地球生态的壮举
a dramatic influence on all life on earth.
数百万年来
For millions of years,
动物被困于水体之中
animals had been confined to the rivers and oceans.
终于 它们可以脱离水体了
Now they could finally emerge from the water.
我们通过模拟过去的方式
We get an idea of those first tentative steps
观察一种五千年来几乎未曾改变的生物
by travelling back in time with a creature
来了解那些试探性的创举
that's barely changed for 500 million years.
这里是美国东海岸
I've come to the east coast of America,
这些古生物仍然在此登陆并进行交♥配♥
where these ancient creatures still come ashore at dusk to mate.
就是它们了
Here they are.
鲎[亦称马蹄蟹]
Horseshoe crabs.
像是来自外星球的生物
Looks like something from another planet.
他用这两只眼睛看东西
He sees with two main eyes here,
但不可思议的是
but they've got something like,
他们的身体散布有十只眼睛
like ten eyes scattered across their body.
而更奇怪的是 当你把它们翻过来
And the really weird bit is if you lift them up.
快看这
Look at that.
首先映入眼帘的便是它们的五双腿
For a start, they've got five pairs of legs.
看 一 二 三 四 五
Look - one, two, three, four, five,
普通螃蟹只有四双腿
whereas normal crabs just have four.
实际上它们更接近于蝎子
They're actually more related
而不是普通螃蟹
to the scorpion than to normal crabs.
看这里
Look at that.
但最有意思的被夹在这下边
But the really interesting bit is tucked under here.
你能摸到的部位叫书腮
You get these things called book gills.
看那里 就像是一捆书
Look at that there. It's like sheaves of a book.
这是它们获得氧气的器官