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《地球脉动2》  第一季  第五集

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地球上四分之一的土地
One quarter of all the land on Earth

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覆盖着唯一一种伟大的植被
is covered by a single, remarkable type of plant.

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它们几乎坚不可摧  一天可以长高六十厘米
Almost indestructible, it can grow two feet in a day...

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连巨型动物都能藏匿其中
And be tall enough to hide a giant.

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那就是草本
That plant is grass,

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草本植物构建出来的世界独具一格
and the world it creates is truly unique.

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印度北部的草是地球上长得最高的
The grass in northern India is the tallest on the planet,

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这里是众多神奇生物的家园
home to some of the most impressive creatures to tread the Earth.

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现在正当好时候
These are the good times,

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可再过几个月  这些青草就会消失
but in just a few months, all this fresh growth will be gone,

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动物们将被迫迁徙
and the animals will be forced to move on.

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地球上的草原都是如此
That is the way things are on grasslands across the planet.

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重复着富足  消亡  重生的循环
A cycle of abundance, destruction and rebirth

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从而影响着栖息在这里的所有生命
that affects every creature that lives here.

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草原

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辽阔的欧亚草原区是地球上最大的草原地带
The largest grassland on Earth, the vast Eurasian Steppe,

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覆盖距离达到地球周长的三分之一
stretches one third of the way around our planet.

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英语解说  大卫·爱登堡

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青草随春雨而生  也带来了新生命
Spring rain has brought fresh grass, and with it, new life.

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一种冰川时代存活至今的生物  高鼻羚羊幼崽
A relic from the Ice Age, a baby Saiga antelope,

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出生才三小时
just three hours old.

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陪伴它的只有它的孪生兄弟
His only company, his twin.

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在它们能站起来之前
Until they can stand,

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母亲会将它们藏在草丛中
their mother has left them hidden in the grass.

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这样应该很安全  只要保持安静
They should be safe, as long as they remain quiet.

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对这两只小羊来说  时间紧迫
For these calves, the clock is already ticking.

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羚羊群很快就要离开
Their herd will soon be moving on,

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去寻找最新鲜的草场
seeking the freshest new grass.

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高鼻羚羊四肢瘦长
Their lanky legs are a sure sign

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预示着它们一生都将奔波在路上
that they're built for a life on the move.

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高鼻羚羊总会产下孪生幼崽
Saiga always give birth to twins,

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这样能够在草源充足时迅速繁衍
so their numbers grow rapidly just when grass is plentiful.

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它们的鼻子长相奇怪  却能够勘测到
Their bizarrely shaped nose can detect fresh growth

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几百公里外的青草长势
from hundreds of miles away.

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这两只小羊即将与其他草原动物一样
The young twins will now begin the nomadic life

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开始辽阔草原上不断迁徙的生活
they share with most animals on the world's open plains.

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降雨量不足以养育森林时就会出现草原
Grasslands occur where rain is too sporadic for forests to exist.

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草原生长所需的年降雨量
The rain that a grassland needs to survive for a year

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可能会一次来临
might arrive all at once.

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这样的暴雨在二十四小时内能达到三百毫米降雨量
Storms like these can release 12 inches of rain in 24 hours.

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淋起来可不好受
Not much fun if you're out in it.

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最终土壤无法继续吸收雨水
Eventually the earth can't soak up any more,

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草原也完全变了样子
and the grassland undergoes a radical change.

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许多植物会被淹死  而草本却会茁壮生长
Many plants would drown here, but grasses thrive.

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它们长得飞快
They grow so fast,

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茎叶迅速伸出水面  沐浴在阳光下
their leaves quickly rise above the water and into the sunlight.

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在南非
Here in southern Africa,

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降水能让世界上最奇特的草原之一改头换面
water transforms one of the most remarkable grasslands on Earth,

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奥卡万戈三角洲
the Okavango.

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每年都有近一万三千平方公里的草原被水淹没
Every year, 5,000 square miles of grassland are flooded.

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对于狮群来说  这成了最大的问题
For one pride of lions, this poses a major problem.

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虽然猎物众多
There may be plenty of prey around,

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但狮子并不擅长在水中捕猎
but lions struggle to run it down in water.

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狮群中有三个月的幼崽
The pride has three-month-old cubs.

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它们以前从未见过水
They've never seen water before.

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如果母狮们短时间内捕不到猎物
If their mothers don't make a kill soon,

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这些幼崽可能撑不过这周
the cubs might not survive the week.

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受洪水滋养
But fuelled by the flood,

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蓬勃生长的青草吸引来新的猎物
the eruption of grass attracts new possible prey.

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数量超过两千头的水牛群接踵而至
Buffalo arrive in herds 2,000 strong.

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强大  好斗  抱团前进
Powerful, aggressive and united,

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狮子能遇到的动物中  水牛是最危险的
they're the most dangerous animal a lion can face.

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体型最大的公牛不会逃跑
The biggest bulls don't run.

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他们仗着身形庞大  并不惧怕狮子
They're simply too huge to be scared of lions.

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重达九百公斤  他比五头母狮加起来都重
At 900 kilos, he weighs more than all five lionesses combined.

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虽然狮群占据了数量优势
The pride do have numbers on their side,

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但如果被水牛角扫到  可能会直接丧命
but one sweep of his horns could be deadly.

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一头母狮正面诱敌
One distracts the bull up front,

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她的姐妹从后方进攻
while her sisters attack from behind.

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母狮们必须想办法压倒公牛
The cats must somehow topple the buffalo,

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但沼泽太过湿滑  脚底无法借力
but with swamp under foot, they can't get any traction.

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公牛逐渐虚弱
The bull is weakening,

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但狮群也露出疲态
but the lions are tiring, too.

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现在是体力与毅力的双重考验
It's now a battle of will as much as strength.

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要想活下去  公牛必须想办法甩掉母狮
To live, the bull must somehow shake off the lioness.

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这头公牛受了伤
The bull is wounded,

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但幸亏有五厘米厚的牛皮  他会慢慢痊愈
but thanks to his two-inch-thick hide, he will recover.

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而狮群  只能忍饥挨饿了
For the pride, these are hungry times.

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但等到水位降低  便会有新生命来临
But, ultimately, once the water recedes, there will be new life,

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也就有了新的食物来源
and new food to benefit all.

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只要条件适宜  草本植物可以在短短几天内
In the right conditions, grasses have the extraordinary ability

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完成从发芽到开花的全过程
to grow from first shoots to flower in a matter of only days.

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青草变成一棵棵微型果树
Grasses become the miniature equivalents of fruiting trees.

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对于住在其中的生物来说
And for creatures living within the grass,

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这样的草丛就像雨林一样高大葱郁
this is a landscape as vast and towering as any rainforest.

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非常适合建造小树屋
And excellent place to build a tiny tree house

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供巢鼠居住
for a harvest mouse.

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夏季的欧洲草原食物充盈
During summer, European meadowlands are full of food,

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只看谁能捷足先登
but only for those that can reach it.

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爬草比爬树更困难
Climbing grass is harder than climbing trees,

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主要是因为草茎不会静止不动
not least because their stems just won't stay still.

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她的尾巴可以抓握物体  就像第五只手
Her prehensile tail acts like a fifth limb,

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让她如林中穿梭的猴子一般敏捷灵活
so she's as agile as a monkey clambering around in a tree.

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和森林中一样
And just as well,

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这片草丛中最好的食物
for the best food in this tiny forest

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也在植株最顶端
is at the very top of its canopy.

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但爬到高处觅食  就会暴露自己
Feeding up here, she's exposed.

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一只仓鸮
A barn owl.

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动作不算灵巧
Not her finest move...

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但也算成功逃命
But it did the trick.

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巢鼠鲜少在地面行动
Harvest mice seldom go all the way down to the ground.

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这里的世界复杂而危险
It's a tangled and dangerous world down here.

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但她能够通过解读头顶的草茎来辨明方向
But she can read the pattern of the stems overhead like a map,

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从而找到回家的路
and so find her way home.

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时机刚好
And not a minute too soon.

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幼崽嗷嗷待哺
There are mouths to feed.

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她的宝宝们必须迅速长大
Her babies must fatten up quickly.

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他们要趁着夏季食物充盈时
They need to harvest the summer grasses

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尽量进食成长
while they're still rich with food.

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非洲稀树草原亦是如此
On the African savannah, too,

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应季时草地生命丰富多彩
seasonal grasses are filled with life,

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但却不会持续太久
but it won't last long.

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红喉蜂虎是卓越的空中猎手
Carmine bee-eaters are superb aerial hunters,

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十分擅长捕食飞行中的昆虫
experts at catching insects in midair.

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但它们无法将猎物赶出草丛
But they have no way of flushing their prey out of the grass.

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一旦警觉起来  大多数昆虫会静止不动
Once alarmed, most insects stay put.

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红喉蜂虎需要找帮手来捣乱
The bee-eaters need someone to stir things up a bit.

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一只灰颈鹭鸨
A kori bustard.

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它是世界上体重最大的飞禽
It's the world's heaviest flying bird,

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凭它庞大的身躯  应该能轰出一些虫子
so it should be bulky enough to kick up some insects.

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成功了
Bingo!

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直到有别的蜂虎加入
Until someone else comes along

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打乱它的计划
and cramps your style.

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没关系  也许等会还有更好的机会
Never mind, perhaps there are bigger opportunities ahead.

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鸵鸟怎么样
What about an ostrich?

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它们是体重最大的鸟类
The heaviest bird of all.

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这次有足够的交通工具了
This time there's more than enough transport to go around.

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很快  几乎每只鸵鸟都有了自己的乘客
Soon, almost every ostrich has its own passenger.

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不过搭便车的也得意不了多久
But free riders are only tolerated for so long.

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蜂虎真正需要的
What the bee-eaters really need

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是体型大到根本注意不到它们的动物
is a creature so big it won't even notice them.

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非洲公象夷平草地之势
Nothing cuts a swathe through grass

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没有动物能与之比肩
like an African bull elephant.

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诀窍是尽可能飞在这位“大块头”的近前方
The trick is to fly as close to
the front of the giant as possible.

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想取得奖赏  必须在刹那间出手
They only have a split second to grab the prize.

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越来越多昆虫被赶出来  竞争也愈发激烈
As more insects are stirred up, the competition intensifies.

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夏天即将结束  储备食物的竞赛已然打响
With summer drawing to a close, the race to stock up is on.

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草很快就会枯萎  屯食良机转瞬即逝
Soon, the grass will wither, and this opportunity will have gone.

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到了旱季
As the dry season takes hold,

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地面的食物愈发稀缺
food becomes increasingly thin on the ground.

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只有在真正身怀绝技的草原捕猎者
Now, only the most specialised predators on the plains

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才能维持生活
can make a living.

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她虽然形似猎豹  但这只猫并非短跑能手
She may be spotted like a cheetah, but this cat is no sprinter.

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相反  修长的四肢给予她独特的猎捕优势
Instead, she has extra-long legs
which give her a high vantage point.

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不过薮猫最主要的武器  是她雷达般的双耳
But a serval cat's main weapon are enormous radar ears.

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能精确定位草丛中猎物的藏身之处
They help her pinpoint prey hiding in the grass.

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可是她的猎物十分机警
But the prey she seeks are canny.

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非洲沟齿沼鼠
Southern vlei rats.

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他们知道持续移动会暴露行踪
They know that any sustained movement can give them away.

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于是选择短距离爆冲
So they move in short bursts.

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但是最细微的窸窣声也会被薮猫察觉
But even the slightest rustle will give her a clue.

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快找到了
Warm.

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更接近了
Warmer.

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没抓到
Missed.

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形势好的时候  她一天能抓十只
In better times, she could catch 10 a day,

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但现在啮齿动物数量极少  她只能挨饿了
but now, with so few rodents around, she will have to go hungry.

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随着干旱加剧  草原生活更加艰难
As drought intensifies, life gets tougher for all.

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定居于此的捕食者只能选择熬过去
Predators with permanent territories must tough it out,

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因为大部分猎物都已远去
while most of their prey disappear over the horizon.

161
00:26:47,190 --> 00:26:48,910
为了抵御饥饿
To avoid starvation,

162
00:26:48,920 --> 00:26:53,460
草原动物大多随水草迁徙
many grassland animals follow a nomadic way of life.

163
00:26:55,450 --> 00:26:59,700
超过两百万头牛羚奔走在东非大草原
Over 2,000,000 wildebeests wander the East African savannahs

164
00:26:59,700 --> 00:27:01,680
追逐着雨水
chasing the rains.

165
00:27:15,820 --> 00:27:18,180
不过它们并不孤单
And they are not alone.

166
00:27:20,280 --> 00:27:21,970
展翅飞来这里
Arriving on the wing,

167
00:27:21,980 --> 00:27:26,010
杰氏巧织雀也在寻找鲜嫩的草
Jackson's Widowbirds also seek fresh grass.

168
00:27:27,940 --> 00:27:31,790
然而  它们却不只是为食物而来
Although, it's not just food that they're after.

169
00:27:36,230 --> 00:27:38,630
这只雄鸟想求偶
This male wants a mate.

170
00:27:41,850 --> 00:27:45,620
为此他已长出漂亮的繁殖羽
He's grown elaborate breeding plumage for this moment,

171
00:27:46,970 --> 00:27:50,320
但他需要舞台来展现自我
but he needs a stage on which to show it off.

172
00:27:54,710 --> 00:27:57,120
细心挑选草茎
By carefully selecting grass blades,

173
00:27:57,120 --> 00:27:59,640
每一根修剪到合适的长度
each trimmed to the correct length,

174
00:27:59,740 --> 00:28:02,400
他正在进行非常独特的创作
he's creating something very special.

175
00:28:17,600 --> 00:28:20,380
他需要一块平地
He needs an even surface,

176
00:28:22,400 --> 00:28:24,120
和一个中央摆设
and a centre-piece.

177
00:28:26,670 --> 00:28:28,560
舞台已经布置好了
The stage is set.

178
00:28:29,490 --> 00:28:34,560
他的单身公寓干净整洁  很能吸引雌鸟
His bachelor pad is sufficiently
neat and tidy to attract a female.

179
00:28:36,160 --> 00:28:37,610
问题是
The problem is,

180
00:28:37,820 --> 00:28:39,190
她能看到吗
can she see it?

181
00:28:43,090 --> 00:28:44,730
他还有竞争对手
He has competition.

182
00:28:55,050 --> 00:28:59,770
园艺设计可能不足以打动女士们
It might take more than a little gardening to impress the ladies.

183
00:29:02,040 --> 00:29:04,130
跳起来是个好办法
Jumping is the right idea,

184
00:29:05,350 --> 00:29:08,060
但他低估了草的高度
but he's misjudged the height of the grass.

185
00:29:18,130 --> 00:29:20,440
他的对手显得很轻松
His rival makes it look easy.

186
00:29:44,360 --> 00:29:47,030
他得加把劲了
Time to raise his game.

187
00:30:23,680 --> 00:30:26,150
不仅要看谁跳得高
It's not only who jumps the highest,

188
00:30:26,150 --> 00:30:29,000
还要看谁能跳得久
but who can keep doing so the longest.

189
00:30:38,020 --> 00:30:43,390
对手们无法坚持下去  相继退出竞争
Unable to go the distance, his rivals drop out one by one.

190
00:30:48,000 --> 00:30:51,600
他的耐力吸引了爱侣
Stamina has won him admirers,

191
00:30:52,600 --> 00:30:56,240
现在可以展示他的求爱舞台了
now he can show off his courtship arena...

192
00:31:05,700 --> 00:31:09,810
再来一场浪漫的捉迷藏游戏
And engage in a little romantic hide-and-seek.

193
00:31:21,950 --> 00:31:25,100
他终于得偿所愿
Finally, he's done enough.

194
00:31:36,870 --> 00:31:41,730
东非大草原养育着成千上万的食草动物
The East African savannahs support millions of grazers.

195
00:31:42,620 --> 00:31:46,580
每年会吃掉数百万吨草
Each year they devour millions of tons of grass,

196
00:31:48,740 --> 00:31:50,900
然而有一种生物
and yet there's one creature here

197
00:31:50,910 --> 00:31:56,450
对草原造成的影响  远大于其他动物的总和
whose impact is far greater than all these animals combined.

198
00:32:00,230 --> 00:32:03,780
地球上有草的地方  都有它们的踪影
They're found wherever grass grows on the planet,

199
00:32:04,130 --> 00:32:07,860
但它们的辛苦劳作几乎难以察觉
yet their labours go almost entirely unnoticed.

200
00:32:12,610 --> 00:32:15,600
其中最出色的
One of the most remarkable is found here

201
00:32:15,600 --> 00:32:18,480
出现在南美洲草原
on the grasslands of South America.

202
00:32:21,390 --> 00:32:23,630
这些叶片十分坚硬
These blades are so tough

203
00:32:23,640 --> 00:32:27,620
几乎没有大型食草动物能消化得了
that virtually no large grass eaters can stomach them.

204
00:32:28,620 --> 00:32:32,820
然而却被小小的切叶蚁
Yet they're harvested on an industrial scale...

205
00:32:36,580 --> 00:32:39,840
大规模采集
...by tiny grass cutter ants.

206
00:32:46,580 --> 00:32:49,890
可它们根本无法消化叶片
But they themselves can't digest one bit of it.

207
00:32:52,830 --> 00:32:54,500
那到底是为什么呢
So, why bother?

208
00:32:58,730 --> 00:33:01,600
答案在地下
The answer is underground,

209
00:33:03,470 --> 00:33:05,990
可谓别出心裁
and it's very ingenious.

210
00:33:10,490 --> 00:33:16,330
每根叶片都被切成一定长度  放入菌圃
Each blade is cut to length and placed into a garden of fungus.

211
00:33:21,230 --> 00:33:24,220
真菌以腐烂的叶片为食
The rotting grass feeds the fungus,

212
00:33:24,220 --> 00:33:28,270
而真菌又成为蚂蚁的食物
and in turn the fungus feeds the ants.

213
00:33:31,650 --> 00:33:36,640
养活五百万劳动者需要大规模的高效耕作
But feeding 5,000,000 workers requires intensive agriculture.

214
00:33:38,910 --> 00:33:42,590
幸好它们都很勤劳
Luckily, they are an industrious lot.

215
00:33:46,910 --> 00:33:52,420
仅这一个蚁群  每年就能收集五百多公斤草
This colony alone will collect
over half a ton of grass every year.

216
00:33:56,400 --> 00:34:00,000
数十亿蚁群遍布全球草原
With billions of ant colonies across the world's grasslands

217
00:34:00,010 --> 00:34:02,570
都在做相同的事
all doing exactly the same thing,

218
00:34:02,740 --> 00:34:06,020
它们消耗的草数量惊人
that's a mind-boggling amount of grass.

219
00:34:35,130 --> 00:34:39,710
据估计  地球上超过三分之一的草
It's estimated that over one
third of the grass that grows on Earth

220
00:34:39,740 --> 00:34:42,970
都会被这种昆虫采去
will be harvested by an insect.

221
00:34:48,860 --> 00:34:50,460
在澳大利亚北部
In northern Australia,

222
00:34:50,460 --> 00:34:55,270
白蚁辛勤的劳作体现在雕塑上
termites memorialise their industry in sculpture.

223
00:35:02,700 --> 00:35:06,450
这些令人叹为观止的白蚁丘有三米高
These astonishing mounds are 10 feet tall.

224
00:35:07,130 --> 00:35:10,320
全部建成南北走向
They're always built on a north-south axis,

225
00:35:10,320 --> 00:35:14,170
因此它们的建筑者被称为罗盘白蚁
which is why their builders are called compass termites.

226
00:35:27,860 --> 00:35:29,720
这些粘土造就的城堡
These castles of clay

227
00:35:29,720 --> 00:35:32,600
保护着它们的主人
protect their builders from extremes of heat

228
00:35:32,600 --> 00:35:37,020
不受草原酷暑和季节性洪水的伤害
and seasonal floods experienced on many grasslands.

229
00:35:48,680 --> 00:35:53,440
白蚁与大多数食草动物不同
Termites manage to do what most grass eaters can't,

230
00:35:54,280 --> 00:35:58,110
它们能分解枯草  提取养分
break down dead grass and extract the nutrients.

231
00:35:59,110 --> 00:36:03,440
但也有动物能探进蚁穴将它们吃掉
But they themselves can be food for those that can reach them.

232
00:36:09,090 --> 00:36:10,910
六十厘米长的舌头
A two-foot-long tongue

233
00:36:12,540 --> 00:36:15,060
上面布满极小的钩子
covered in microscopic hooks,

234
00:36:18,320 --> 00:36:23,050
加之比迅猛龙还要长的爪子
followed by claws longer than those of a velociraptor.

235
00:36:29,140 --> 00:36:33,020
这是一只生活在南美平原上的大食蚁兽
A giant anteater on the plains of South America.

236
00:36:37,990 --> 00:36:41,300
它每天可以吞食两万只昆虫
It can devour 20,000 insects a day.

237
00:36:46,630 --> 00:36:52,270
有力的前肢让它们能够轻易地掰开白蚁巢
Powerful forelegs enable it to rip apart a termite hill with ease.

238
00:37:02,490 --> 00:37:08,080
太阳炙烤草原  白蚁面临着新的危险
And as the sun bakes the grass, the termites face new danger.

239
00:37:31,020 --> 00:37:35,440
几分钟内  大火就将草原化为灰烬
In minutes, fire turns grassland to ash.

240
00:37:49,580 --> 00:37:51,810
但是草不会被大火烧尽
But the grasses are not dead.

241
00:37:52,350 --> 00:37:55,800
它们的地下茎完好无损
Their underground stems are unharmed.

242
00:37:58,760 --> 00:38:01,570
数周  数月就这么过去了
Weeks, months may pass,

243
00:38:01,680 --> 00:38:04,540
但是雨季终将来临
but eventually the rains will return

244
00:38:04,540 --> 00:38:06,910
青草又会重新发芽
and the grass will sprout again.

245
00:38:14,120 --> 00:38:19,890
一些草原不仅要忍受火的炙烤  还有冰霜
Some grasslands must endure not only fire, but ice.

246
00:38:25,010 --> 00:38:26,720
冬季来临
As winter approaches,

247
00:38:26,720 --> 00:38:30,300
北美的草原开始霜冻
the prairies of North America begin to freeze.

248
00:38:46,630 --> 00:38:49,260
夏季  美洲野牛四处漫步
In summer, bison roamed freely,

249
00:38:49,270 --> 00:38:53,350
享用着取之不尽的大片青草
almost continuously cropping the abundant green grass.

250
00:38:55,030 --> 00:38:58,330
现在青草不仅枯萎结冰
Now, that grass is not only withered and frozen,

251
00:38:58,730 --> 00:39:00,840
马上还会被大雪掩埋
it's about to be buried.

252
00:39:22,960 --> 00:39:28,270
六千万吨的积雪覆盖在野牛群的领地上
Sixty million tons of snow now blanket this herd's territory.

253
00:39:31,960 --> 00:39:35,270
在厚厚的积雪中行动非常耗费体力
Pushing through deep snow is exhausting work,

254
00:39:35,370 --> 00:39:38,490
美洲野牛越来越饥饿
and the bison are now slowly starving.

255
00:39:45,480 --> 00:39:49,240
仅仅保暖都需要耗费大量的能量
Just keeping warm saps huge amounts of energy.

256
00:39:55,420 --> 00:40:00,100
他们厚重的皮毛可耐受零下三十度的低温
Their thick coats can insulate them down to minus 20 Fahrenheit.

257
00:40:00,800 --> 00:40:02,970
现在是零下四十度
It's now minus 40.

258
00:40:06,030 --> 00:40:08,740
唯一能让他们活下去的食物
The only thing that will keep them alive

259
00:40:08,920 --> 00:40:11,800
被深埋在一米深的积雪之下
is buried beneath three feet of snow.

260
00:40:16,740 --> 00:40:20,780
他们意想不到的邻居也面临着同样的问题
And that's a problem shared with a surprising neighbour.

261
00:40:39,030 --> 00:40:43,100
狐狸在搜寻的食物也被深埋在积雪之下
The food the fox seeks is also deep beneath the snow.

262
00:40:55,730 --> 00:40:57,920
这两种生物能否生存下去
The survival of both creatures

263
00:40:57,920 --> 00:41:00,910
取决于能否挖到地面的食物
depends on getting through to the ground.

264
00:41:06,350 --> 00:41:10,460
对于美洲野牛来说  用蛮力就可以做到
For the bison, it will be a matter of brute strength.

265
00:41:15,000 --> 00:41:20,370
强大的颈部肌肉让他们每天可以铲五吨的雪
Massive neck muscles enable them
to shovel five tonnes of snow a day.

266
00:41:26,760 --> 00:41:30,110
他们小巧的邻居则需要更高的准头
Their light-weight neighbour needs more precision.

267
00:41:58,370 --> 00:42:00,990
美洲野牛达到了目的
The bison have reached their goal,

268
00:42:01,310 --> 00:42:04,150
一大口枯草
a mouthful of withered grass.

269
00:42:07,880 --> 00:42:12,850
在美洲野牛挖过的地方狐狸也见缝插针
And where the bison have dug, the fox now spots an opportunity.

270
00:42:21,860 --> 00:42:24,450
每一步都至关重要
Every footstep counts,

271
00:42:27,020 --> 00:42:29,020
但是时机...
but he mustn't break through...

272
00:42:29,940 --> 00:42:30,920
还未到
Yet.

273
00:42:34,270 --> 00:42:38,220
他仔细监听着猎物的一举一动
He listens carefully to pinpoint his target.

274
00:42:43,800 --> 00:42:45,130
它在移动
It's moving.

275
00:43:07,440 --> 00:43:08,680
一只野鼠
A vole.

276
00:43:11,110 --> 00:43:14,520
虽然小  但是比一嘴干草的
Small, but 100 times more nutritious

277
00:43:14,530 --> 00:43:17,270
营养价值高上百倍
than a mouthful of dried grass.

278
00:43:23,640 --> 00:43:26,370
想要在这草原上度过严冬
To get through the winter on these prairies,

279
00:43:26,370 --> 00:43:30,470
有时候脑子比蛮力更加重要
sometimes brain beats brawn.

280
00:43:36,950 --> 00:43:40,130
最终  所有草原上的生物
Ultimately, life on all grasslands

281
00:43:40,130 --> 00:43:43,140
都依赖于季节的更迭
depends on the turn of the seasons.

282
00:44:09,450 --> 00:44:13,600
在树木生存极限八百公里以北的地方
Five hundred miles further north than any tree can survive,

283
00:44:13,610 --> 00:44:16,120
青草春风吹又生
grass returns to life.

284
00:44:27,210 --> 00:44:30,800
雌性北美驯鹿远赴北方
Caribou females have journeyed to the far north

285
00:44:31,350 --> 00:44:32,790
来此产仔
to calve.

286
00:44:36,530 --> 00:44:39,420
超过七万只驯鹿幼崽
Over 70,000 caribou babies

287
00:44:39,420 --> 00:44:42,090
将在几天内出生
will be born in the next few days.

288
00:44:46,470 --> 00:44:48,180
小鹿出生的时候
As the calves appear,

289
00:44:48,180 --> 00:44:51,990
也正是青草发新芽的时候
so too do the leaves of the newly sprouting grass.

290
00:44:55,140 --> 00:44:57,660
幼鹿必须迅速增强体能
And the calves must strengthen quickly.

291
00:44:57,670 --> 00:45:01,150
几天内他们就将跟随自己的父母
Within days they will have to keep up with their parents

292
00:45:01,150 --> 00:45:03,630
踏上无尽的征程
on a never-ending march.

293
00:45:09,000 --> 00:45:13,880
第一天  他们的速度就已经超过人类短跑健将
At one day old, they're already faster than an Olympic sprinter.

294
00:45:15,050 --> 00:45:19,270
他们正在测试自己跋山涉水用的四肢
They're testing the legs that will carry them thousands of miles,

295
00:45:20,720 --> 00:45:23,350
最好现在就知道极限在哪里
better to learn their limitations now.

296
00:45:43,790 --> 00:45:48,110
看起来很好玩  但草原上最艰苦的生活
It may look playful, but there's no harder life on the grasslands

297
00:45:48,110 --> 00:45:51,200
正等着这些他们
than that facing these infants.

298
00:45:54,450 --> 00:45:56,900
母驯鹿现在聚集起来
The caribou mothers now join together,

299
00:45:56,900 --> 00:46:00,540
每只都带着一只同样大小的幼鹿
each with an infant exactly the same age.

300
00:46:09,160 --> 00:46:11,080
她们准备启程
They're setting off on the greatest

301
00:46:11,080 --> 00:46:14,880
进行陆地上最伟大的长途跋涉
overland trek made by any animal.

302
00:46:38,560 --> 00:46:41,540
但是无论草食性动物走到哪里
But wherever grass eaters travel,

303
00:46:41,650 --> 00:46:44,190
都有捕食者等待着他们
predators lie in wait.

304
00:46:50,970 --> 00:46:55,510
就是他们  北极狼
Here they are, Arctic wolves.

305
00:47:02,440 --> 00:47:04,360
他们必须要在
They must seize their chance

306
00:47:04,360 --> 00:47:07,350
驯鹿经过领地时把握住机会
while the caribou pass through their territory.

307
00:47:44,420 --> 00:47:46,680
北极狼跑向鹿群
The wolf runs at the herd,

308
00:47:46,680 --> 00:47:49,660
试图冲散群体中的弱者
trying to flush out the weak or the slow.

309
00:47:59,320 --> 00:48:01,370
一只幼鹿走散了
A calf is separated.

310
00:48:09,570 --> 00:48:12,310
狼全力以赴捕猎的时速将近六十公里
At full tilt, 40 miles an hour,

311
00:48:12,420 --> 00:48:14,550
只比小鹿快一点点
the wolf is just faster.

312
00:48:23,120 --> 00:48:25,870
但是幼鹿的耐力更好
But the calf has stamina.

313
00:48:56,540 --> 00:48:58,750
虽然只有几周大
Only a few weeks old,

314
00:48:58,750 --> 00:49:02,590
这只幼鹿的求生欲望让人叹为观止
and this calf's will to survive is remarkable.

315
00:49:07,740 --> 00:49:09,930
而且必须如此
And it needs to be,

316
00:49:10,090 --> 00:49:13,610
这些幼鹿开始了一场
for these young caribou have now started a journey

317
00:49:13,610 --> 00:49:15,970
终其一生的旅程
that will last a lifetime.

318
00:49:19,050 --> 00:49:22,610
永远追寻着他们所需要的
Forever chasing the seasonal growth of the grass

319
00:49:22,610 --> 00:49:24,360
季节性生长的青草
on which they depend.

320
00:49:33,460 --> 00:49:36,740
和其他草原生物一样  他们依赖着
Like all grassland creatures, they are at the mercy

321
00:49:36,740 --> 00:49:41,870
这变化莫测而又极其慷慨的大草原
of these unpredictable but ultimately bountiful lands.

322
00:49:47,940 --> 00:49:52,180
青草可以在地球上最为极端的环境下生长
Grass can survive some of the harshest conditions on earth,

323
00:49:52,180 --> 00:49:57,030
经受洪水  火灾和冰霜的考验仍然生机盎然
flood, fire and frost, and still flourish.

324
00:50:07,290 --> 00:50:10,960
所以草原为地球上
So it is that grasslands provide a stage

325
00:50:10,980 --> 00:50:15,520
最壮观的野生动物群提供了舞台
for the greatest gatherings of wildlife on planet earth.

326
00:50:23,370 --> 00:50:24,480
下集预告
Next time,

327
00:50:25,540 --> 00:50:28,540
我们向地球上最新的栖息地进发
we venture to the newest habitat on Earth,

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我们的城市
our cities.

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揭示在这个人造的世界中
To reveal the extraordinary ways

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动物们神奇的生存方式
that animals survive in this man-made world.