种出个地球（1）

they made up the planet's first tropical forests.
这第一片森林遍布于地球热带的沼泽中
Found in swamps throughout the Earth's tropics,
它是如此的广阔
these first forests were so extensive,
在太空中能看见一抹深绿
you'd have seen a band of dark green from space.
所有的新叶子都在喷出氧气
And all those new leaves were pumping out oxygen,
增长的氧气水平线
so much that levels of oxygen increased
差不多是现今的两倍
to not far off double what they are today.
这对动物产生了非常奇怪的影响
It was having a very odd effect on animals...
尤其是昆虫及其同类
in particular, insects and their cousins.
无脊椎动物有简单的呼吸管 没有肺
Instead of lungs, invertebrates have simple breathing tubes
呼吸靠扩散氧气到内部器官
that rely on diffusion for oxygen to reach their internal organs.
受空气中氧气浓度的影响
The size of these animals is therefore limited
这些动物的体型受到限制
by the concentration of oxygen in the air.
而在这第一片森林里 氧气大量增加
Increase the oxygen, just as the first forest did,
情况就很有趣了
and things get interesting.
看见这块岩石上的印记了吗
Do you see these markings on the rock here?
两条小凹痕 这有一条 这有一条
There's two lines of little dents, one here and one here.
这是化石足迹
They are fossilised footprints
可追溯到非常早期的森林
that date back to the very early forests.
科学家初次研究时
When scientists first studied them
意识到这不是爬行或两栖类动物造成的
they realised they weren't made by some reptile or amphibian.
这是千足虫的足迹
They were made by a millipede.
这是如今地球上最大的
Now, here is one of the biggest millipede species
千足虫之一
alive on Earth today.
真够大的
That's pretty big.
由这些足迹的规模来看
Using the tracks for scale,
这个小家伙的祖先显然十分庞大
it's clear the ancestors of this little fellow were massive.
这是节胸蜈蚣 身长两米有余
Called Arthropleuridea, it was over 2m long.
那时的森林真是可怕
The forests would have been terrifying.
有巨大的蝎子和巨大的蜘蛛
With giant scorpions and giant spiders.
不仅陆地上是如此
And not just on the land.
体型对比最惊人的还属蜻蜓
I think the most impressive of all were the dragonflies.
现在大部分的蜻蜓加翼长最多十厘米
Most modern dragonflies have wing spans up to 10cm across,
在那时可要大多了
but back then they were way larger.
有些可长达一米
Some were up to a metre across.
这些巨脉蜻蜓是能飞上天空的
These Meganeura were the largest insects
最大的昆虫
ever to take to the skies.
但在这个注满了氧气的特大号♥世界里
But in this oversize world pumped with oxygen,
植物王国仍然享有霸权
the plant kingdom still reigned supreme.
接下来 也就是两亿三千万年前
Then, 230 million years ago,
新的一群动物
a new group of animals
出现在潮湿森林的阴影之中
emerged from the shadows of the swampy forests.
它们会成为行走在地球上最大的生物
They would become the largest creatures to roam the Earth
同时也准备好与植物王国一决雌雄
and they were ready to do battle with the kingdom of the plants.
当然 我指的是恐龙
I'm talking, of course, of dinosaurs.
肉食性动物感受到了压力
It's the meat-eaters that get all the press.
但最近的研究显示
But recent research has revealed
在已发现的七百个恐龙物种之中
that out of the 700 species discovered,
超过三分之二的恐龙是食草性的
over two-thirds were herbivores.
素食是王道
Vegetarians ruled,
而其中 史上最大的草食动物
led by the biggest herbivores in history
是蜥脚类恐龙
the sauropods.
为查明这些巨大恐龙
To discover the impact of these huge dinosaurs
对植物王国造成的影响
on the plant kingdom,
我来到一个动物保护区 好亲眼瞧瞧
I've come to an animal sanctuary to see it in the flesh.
不幸的是 这里没有活的蜥脚龙
Unfortunately this place doesn't have a living sauropod,
可这里有这世界上所拥有的
but what it does have is the biggest herbivore
最大的食草动物
that the planet's got to offer -
非洲象
the African elephant.
来认识下"布奇"
Come and meet Butch.
这头美丽的四吨♥重大象能让我真正体会到
This beautiful four-tonne elephant can help me truly appreciate
恐龙那压倒性的体型
the staggering size of the dinosaurs.
上升吧
Can we go up?
最大的非洲公牛有布奇这么大
Butch here is about as big as a big African bull gets
也就是有四米高了
and that's already four metres high,
但要达到蜥脚龙的高度
but if we want to get to the height of a sauropod,
还得要升高很多
we have to go much higher.
六米高 还得升高
Six metres. We've got to be higher than that.
现在有八米高了
We're now at eight metres.
还得继续升高
We've still got to go higher.
几米了 十米高了 还得再高点
Where are we at? Ten metres now? A bit higher than that.
还没达到蜥脚龙的高度
We're still not at the height of a sauropod yet.
好了 差不多到了
OK, we're getting there. Nearly.
可以了
OK, fine.
我的头位于十二米高处
So my head's now about 12 metres,
差不多是四层楼的高度
which is about the height of a four-storey building
也就是蜥脚龙的身高
and also the height of a sauropod.
要注意的是在九米长脖子的尾端
The thing is, on the end of a nine-metre neck,
这是一头蜥脚龙的头骨
this is the skull of a sauropod.
看起来很小
It seems quite small.
但关键是它能灵活机动地
But the point was that this had to be manoeuvrable and nimble
采摘高处的树叶
to get right up at that high-level foliage.
蜥脚龙是地球上前所未有的动物
Sauropods were like nothing else the planet had ever seen.
它们的体重可达非洲象的10倍以上
They weighed more than ten times an African elephant.
布奇每天都要吃掉大约90公斤的草料
Now, Butch here eats about 90kg of foliage every day,
也就相当于这么多草
which is roughly about that much hay
但科学家经过估算后发现
But scientists have estimated
蜥脚龙每天大约能吃掉1.5吨♥草料
that sauropods ate about 1,500kg of hay every day.
换句话说 相当于大象的二十倍
In other words, about 20 times that daily diet.
或者是50捆干草
Or 50 bales of hay.
假如你想象一下一群比大象大多了的
Now if you imagine you've got herds of about 30 sauropods,
30头规模的蜥脚龙群
much bigger than these beasts here,
你就会意识到 植物王国所面临的
and you realise that the plant kingdom
是多么强大的素食天敌
was up against the ultimate salad predator.
一亿五千万年前
150 million years ago,
恐龙们疯狂地掠食着广袤的树林
dinosaurs were stripping the land of vast swathes of foliage.
有史以来第一次 植物们面临着
For the first time, the plant kingdo was under serious attack
来自另一种群的强大攻势
from another dynasty.
为了反击 植物进化出一系列的武器
To fight back, plants began to evolve a whole arsenal
来保卫它们珍贵的叶子
of defences for their precious leaves.
在美国加州
Here in California,
我们可从这座世界上最不同寻常的花房♥中
we can see just how intense this arms race was
一窥植物们的军备竞赛有多么激烈
in one of the world's most unusual gardens.
这里到处都是这种
It's full of a group of bizarre
奇异且稀有的苏铁属植物
and extremely rare plants called cycads
但曾经 地球上每四棵植物中
but once, they made up a quarter of
就有它们的身影
all plants on Earth.
这真是太不可思议了
This is incredible.
真的是和古时候
Exactly the kind of place
恐龙出没的的地方一模一样
you'd expect a dinosaur just to pop out.
为了抵御那些贪得无厌的食草恐龙
To stave off attack from those ravenous dinosaurs,
苏铁植物想出了对付它们的绝佳办法
cycads developed some clever lines of defence,
而且很明显这是一种物理方法
the most obvious being physical weapons
就像针和钉子一样 真是好尖啊
like needles and spikes and... Agh! These are vicious.
这种方法的主要目的
The main point was to make leaves
就是尽可能让叶子吃着很疼
as painful as possible to eat.
这些防御机制的大小外形如出一辙
These defences came in all shapes and sizes.
然而有些植物为了进一步加强防御
And some plants also spiced things up
还进化出了化学武器
with chemical weapons.
这是一株南非的岩谷苏铁
This is a Trapps Valley cycad from South Africa,
是种典型的有毒植株
but it's pretty typical in that
因为它的叶子里有一种神经毒素
the leaves contain a nerve agent
如果你吃掉了它 就会引起呕吐腹泻
that if you ingest it, it causes vomiting, diarrhoea,
以及嘴唇麻痹
paralysis of the limbs
当然了 还会导致死亡
and then, of course, death.
所以很明显我不会吃这些叶子
Obviously I'm not going to eat one of the leaves,
但是我可以食用一种
but I can eat a plant whose ancestors emerged
自恐龙时代就存在的植物
around the time of the dinosaurs
它也是配备化学武器的植物 那就是
and who also have a chemical weapon and that is...
辣椒
..A chilli.
一株典型的哈瓦那红辣椒