我们星球上的生命（2023）

地球生命的40亿年历程中
In the four billion years of life on our planet,
无数物种兴起
countless species have risen...
然后衰亡
and fallen.
但有一个非凡的王朝 比其他任何王朝都更具影响力
But one remarkable dynasty has had a greater impact than any other.
哺乳动物
The mammals.
本集将讲述它们史诗般的征程
This is the story of their epic journey...
成为地球统治者的故事
...to become rulers of the world.
《我们星球上的生命》
双语合并：村儿南
第 7 章：地球继承者
躲藏在古代侏罗纪森林之中
Hidden in the ancient Jurassic forests...
哺乳动物出身卑微
mammals came from humble beginnings...
被史上最伟大的王朝所统治
ruled over by the greatest dynasty that ever lived...
恐龙
...the dinosaurs.
它们的统治非常彻底
They dominated so totally...
以至于早期的哺乳动物只能躲在暗处
...that early mammals were confined to the shadows.
在大部分情况下 它们都很小 在树上栖息
For the most part, they were small, keeping to the trees...
远离巨兽
away from the giants.
它们变成了夜行性动物
They became nocturnal,
发展出一系列敏锐的感官
developing a range of heightened senses
帮助它们在黑暗中生存
that helped them in the dark.
在恐龙的统治之下
Under the dinosaurs' rule,
它们的崛起受到限制
there was a limit to how far they could rise.
但是随着时间的推移 一切都改变了
But in time, everything changed.
地球历史上最剧烈的事件之一
One of the most violent events in our planet's history
带来了一个新的时代
heralded a new era.
尽管遭受严重破坏
Despite the devastation,
但地球最终还是得以恢复
the planet did recover.
在几百万年内
Within a few million years,
森林已重新生长并覆盖大部分陆地
forests had regrown and carpeted much of the land.
气候变得炎热潮湿
The climate became hot and wet.
这是生命蓬勃发展的理想条件
The perfect conditions for life to flourish.
这个世界 非常适于新一波进化浪潮的掀起
A world primed for a new wave of evolution.
小行星碰撞 对哺乳动物造成毁灭性的打击
The asteroid had inflicted devastating losses on the mammals...
但有一些小型哺乳动物
yet some of the smaller ones,
藏在洞中 幸存下来
able to hide in holes, had survived.
没有了恐龙
Free of the dinosaurs,
它们终于可以走出阴影
they could finally venture out of the shadows
来到广阔的世界之中
and come into the open.
与它们的祖先一样
Like their ancestors,
长鼻浣熊拥有许多适应性
coatis have many adaptations
能够帮助它们 在富饶的雨林中兴旺发展
that help them thrive in the rich rainforest.
它们的社会性极强
Extremely social,
在群体中寻找安全
they find safety in numbers.
母浣熊灵活的鼻子 能够嗅到藏在树叶下的食物
The mother's flexible nose can smell food hidden beneath the leaf litter.
这是在数百万年夜间觅食的过程中 磨练出来的超凡感官
A supersense honed over millions of years of foraging in the darkness.
与所有哺乳动物一样
Like all mammals,
长鼻浣熊是温血动物
coatis are warm-blooded,
因此能够随时保持活跃状态
so can be active at all times.
这意味着这些宝宝需要足够的能量
That means these babies need plenty of energy.
幸运的是
Fortunately,
哺乳动物 已经进化出一种非凡的解决方案
mammals have evolved an extraordinary solution.
母乳
Milk.
它们可以随时喂养幼崽
They can feed their young whenever they choose,
甚至包括食物稀缺的时候
even when food is scarce.
但是母乳并不是 早期哺乳动物唯一的秘密武器
But milk wasn't the early mammals' only secret weapon.
它们还拥有脑力
They also had brain power.
这在今天依然非常重要
And it's still just as important today.
在哥斯达黎加的森林中
In the forests of Costa Rica,
这只卷尾猴正在努力解开一道谜题
this capuchin monkey is trying to solve a puzzle.
如何吃到蛤蜊里面的肉
How to get the meat from inside a closed clam.
猴子不够强壮 无法砸碎蛤蜊壳
The monkey isn't strong enough to crack the shell...
但它发现反复敲打会令蛤蜊疲惫
but it's discovered that repeated hammering will tire the clam...
直到蛤蜊最终张开
until it finally opens.
学会这一课需要巨大的脑部
Learning this lesson takes a large brain...
以及良好的协调能力
...and coordination.
这种独特的智慧
This unique intelligence
使它们的灵长类祖先 能够在5000万年前的森林中存活下来
allowed their primate ancestors to survive in the forest of 50 million years ago.
聪明的动物往往会很好奇
Clever animals tend to be inquisitive...
这可能带来丰厚的回报
and that can pay huge dividends.
这只母猴发现并记住了…
This female has learned and remembered
在哪里能找到水
where she can find water.
但是太深够不着
But it's too deep to reach.
幸好它有一个巧妙的解决方案
Luckily, she has an inspired solution.
它把自己的尾巴当作海绵
She turns her tail into a sponge.
但并不是所有的挑战 都与寻找食物和水有关
But not all their challenges are to do with finding food and water.
采摘有些水果并不是为了吃
Some fruit is collected not to eat...
而是用于擦拭身体
but to rub over their bodies.
这种水果含有香茅油
This fruit contains citronella,
能够驱蚊
an oil that mosquitoes can't stand.
猴子们发现了它们自己的驱虫剂
The monkeys have discovered their very own insect repellent.
没有了讨厌的昆虫叮咬
Free from pesky biting insects,
聪明的卷尾猴终于可以放松一下了
the clever capuchins can finally relax.
但正当它们的祖先开始取得进展时
But just as their ancestors were beginning to make progress,
曾令它们兴旺发展的暖湿条件 开始发生变化
the warm, wet conditions in which they had thrived began to change.
（3400万年前）
南极大♥陆♥开始从南美洲分离
The Antarctic landmass started to split away from South America...
为新的洋流创造了空间
creating the space for new ocean currents...
这有助于推动全球变冷
that helped drive a global cooling.
气候正在转入一个新的更寒冷的状态
The climate was switching into a new, colder state.
但这还只是一个开始
But that was just the beginning.
随着南极变得更加寒冷与孤立
As Antarctica became colder and more isolated,
整个南极大♥陆♥冻住了
the huge continent froze,
将地球上的大量淡水锁住
locking up much of the planet's fresh water.
随着世界北部进一步干旱
As the world further north dried out,
它成为了 一个更恶劣、更难以生存的地方
it became a harsher, more difficult place to live.
食物变得更分散
Food became more spread out,
更难以寻找
harder to find.
随着地球的改变
And as the Earth changed,
哺乳动物也在改变
so did the mammals.
有一些变得很庞大
Some became enormous.
一只雄性巨角犀
A male Megacerops.
2.5米高
Two and a half meters tall...
4米长
...four meters long...
3吨♥重
and three tons in weight.
巨大的身躯 使它能够长途跋涉寻找食物
Its huge size allows it to travel large distances in search of food...
并能够有所储备 以便挺过食物较少的时期
...and ensures it has reserves to get through leaner times.
哺乳动物此时已非常庞大
Mammals were now big enough
能够与消失已久的恐龙相媲美
to rival the long-lost dinosaurs.
但庞大也有别的影响
But being big has other implications...
尤其是在寻找配偶时
especially when it comes to finding a mate.
这只雌巨角犀 已经被一只雄巨角犀严密地守护着
This female is already closely guarded by a male,
比之前那只雄巨角犀大很多
much larger than the first.
如果受到挑战
If challenged,
它能够重伤对手
he could seriously injure his opponent.
但较小的这只雄巨角犀运气不错
But the smaller male may be in luck.
又来了一只雌巨角犀
Another female,
它似乎孤身一人
and she seems to be alone.
等待已久的机会终于到来
It's the chance he's been waiting for.
居然还是有对手
He has a rival.
这次它们旗鼓相当
This time, they're evenly matched.
对于这些哺乳动物来说
With these mammals...
大小很重要
...size matters.
但即便是最强大的巨角犀
But even the mightiest Megacerops
也无法克服 地球面临的下一个严峻挑战
couldn't overcome the planet's next great challenge.
南极洲的形成正在造成全球气候混乱
The formation of Antarctica was creating global climate chaos.
随着洋流的变化
As ocean currents shifted
以及地球变干
and the planet dried...
地球变得一点就着
it became a tinderbox.
野火在陆地上肆虐
Wildfires ravaged the land...
为一种完全不同的东西铺平了道路
clearing the way for something completely different...
这将对哺乳动物提出前所未有的挑战
something that would challenge mammals as never before.