我们星球上的生命（2023）

年长的骇鸟不能无视威胁
The older one can't ignore the threat.
年轻的骇鸟拒绝退让
The youngster refuses to back down.
它需要自己的领地
He needs a territory of his own.
两只鸟开始了一场仪式性的展示
The two begin a ritual display.
评估对方的力量
Assessing the other's strength...
同时炫耀自己的力量
...while showing off their own.
它们协调一致的动作
Their coordinated moves
像舞蹈一般正式
as formal as a dance.
谁会率先退却？
Who will be the first to back down?
或者率先出击？
Or attack?
没有东西将它们隔离 大战不可避免
With nothing to separate them, a fight is inevitable.
但现场不仅有它们
But they have company.
刃齿虎作为哺乳动物的狡黠
The Smilodon's mammalian cunning
是骇鸟灭绝的原因之一
was one reason terror birds went extinct.
物种内及物种间的竞争
Competition, both within and between species,
一直推动着进化
has always driven evolution.
但不断变化的 不仅仅是参与战斗的生物
But it's not just those doing battle that are always changing.
战场本身也在不断变化
So too is the battlefield itself,
这产生了生命的第三条法则
which leads to the third rule of life.
地球从不会长♥期♥保持稳定
Earth never remains stable for long.
有时候这有助于生命
Sometimes that helps life.
有时候阻碍生命
Sometimes it hinders it.
纵观历史 火山一直是最大的变化因素之一
Throughout history, volcanoes have been one of the greatest agents of change.
持续数千年的喷发
Eruptions lasting thousands of years
反复地吞没地球上的广阔区域
have repeatedly engulfed vast swathes of our planet.
向大气中排放气体
Pumping gases into the atmosphere,
改变气候
changing the climate,
在最糟糕的情况下
and, at worst...
导致全球大规模物种灭绝
...causing global mass extinction.
地球很少呈稳定状态
The world has rarely been stable.
有时是火的天下
At times, a realm of fire.
有时是冰的天下
At times, a realm of ice.
我们不断变化的星球 为生命制♥造♥了诸多挑战
Our changing planet has created so many challenges for life.
从毒海
From toxic seas...
到全球荒原
...to global wastelands...
以及几乎无休止的降雨期
and periods of almost endless rain.
在四个不同的时期
At four different times,
地球将生命推到了灭绝边缘
the planet has pushed life to the very edge of existence.
每一次 超过四分之三的物种
Each time, more than three-quarters of all species
在大规模灭绝中消失
were lost in mass extinctions.
我们的星球有时候很残酷
Ours can be a brutal planet.
（7600万年前）
但曾经有一个时期
But there was one period
地球保持了一亿年稳定状态
when Earth was stable for 100 million years.
这个时期 令一个物种群建立了最强大的王朝
A period which allowed one group to become the mightiest of dynasties.
那就是恐龙时代
This was the age of dinosaurs.
长♥期♥的平静令恐龙数量激增
The long calm helped dinosaurs to proliferate in huge numbers.
这些是慈母龙
These are Maiasaura,
温和的食植动物 数以千计 成群结队
gentle plant eaters that form herds many thousands strong.
这种大规模聚集能够提供安全
This mass gathering provides safety,
不光是为成年个体
and not just for the adults.
这只小心的母龙
This rather cautious female
迫切想要回到巢穴
is keen to get back to her nest.
顾名思义 慈母龙的意思是慈祥的母亲
Maiasaura means "good mother."
与其他母龙一样
Like the other females,
它在一个巨大的聚落中筑巢
she has made her nest in an enormous colony.
为了到达巢穴
To reach it,
它必须穿过一长排保护心极强的母龙
she must run the gauntlet of defensive mothers keen to protect their young.
为了躲避一个挑衅者
In avoiding one aggressor,
它却又太靠近了另一个挑衅者
she strays too close to the next.
最后 它到达了自己的巢穴
At last, she reaches her own nest.
它以一种与鸟类非常相似的方式 喂养幼龙
She feeds her young in a very bird-like way.
它会在巢穴中保护它们达数月之久
She'll protect them in the nest for many months,
直到它们长大到足以加入龙群
until they are big enough to join the rest of the herd.
然而 地球不仅支撑了大量的恐龙
Yet the planet didn't just support large numbers of dinosaurs,
地球的稳定 也支撑了各种形状和大小的恐龙
its stability also supported dinosaurs of every shape and size.
三角龙 与无防御能力的慈母龙非常不同
Triceratops is very different to the defenseless Maiasaura.
它体重五吨♥ 长有三只角
Weighing five tons and boasting three horns,
全副武装
she is heavily armored...
适应了这样一个世界
adapted to a world
在这里 最好的防守就是进攻
where the best form of defense is attack.
繁殖季节临近 它必须进入巅峰状态
With the breeding season imminent, she needs to be in peak condition.
这意味着不论去哪里 都要尽可能找到最好的食物
And that means finding the best food wherever she can.
但觅食令它远离了龙群
But her search has taken her far from the herd...
接近了森林的边缘
and closer to the edge of the forest.
它紧张是对的
She's right to be nervous.
三角龙不是森林中唯一的巨兽
Triceratops aren't the only giants in these woods.
霸王龙
Tyrannosaurus rex.
终极捕食者
The ultimate predator.
它带着两只幼龙
She has her two youngsters with her.
两只幼龙比母亲更快
The siblings are faster than their mother.
它们团队协作
They work as a team.
三角龙能抵挡两只幼龙
The Triceratops can hold off the youngsters,
但无法抵挡成年霸王龙
but not the adult.
只有龙群的保护才能救它
Only the protection of the herd can save her.
它们排成防守墙
They form a defensive wall.
哪怕世界上最强大的捕食者 也知道什么时候该认输
Even the world's greatest predator knows when she's beaten.
雄性幼龙就有点不知进退了
Unlike the young male.
（6604万年前）
如果地球的条件保持不变
Dinosaurs might still rule today
今天恐龙可能仍在统治世界
if conditions on Earth had remained the same.
但一切都将改变
But everything was about to change,
一天之内 天翻地覆
and in just one day.
一颗珠穆朗玛峰大小的小行星
An asteroid the size of Mount Everest,
速度比子弹快20倍
traveling 20 times faster than a bullet,
撞击地球
smashed into the planet.
在地球上造成了一个20公里深 180公里宽的巨大坑洞
It blew a hole 20 kilometers deep and 180 wide...
引发了一系列震撼世界的连锁事件
setting off an earth-shattering chain of events.
从巨大的陨石坑中升起的 才是真正的杀手
Rising from the massive crater came the real killer.
一道粉尘和碎片组成的墙 厚达数百公里
A wall of ash and debris hundreds of kilometers thick...
覆盖了整个地球
that enveloped the globe.
乌云遮住阳光
The cloud blocked out the sunlight,
导致恐龙几乎全部死亡
leading to the death of almost all dinosaurs...
地球上四分之三的生命化为乌有
...and three-quarters of life on Earth.
毁灭是全球性的
The annihilation was global.
这是世界上第五次大规模灭绝
It was the world's fifth mass extinction.
但也有幸存者
But there were survivors.
这些幸存者将成为 今天存在的所有物种的基础
Survivors that would form the basis of all species that exist today.
鸟类是唯一幸存的恐龙
The birds were the only remaining dinosaurs.
如今 鸟类有超过一万个物种
Today, they number more than 10,000 species...
占据着地球上每一个栖息地
...occupying every habitat on Earth.
但鸟类并未独占地球
But the birds didn't have the planet to themselves.
另一个伟大的王朝也从废墟中崛起
Another great dynasty also rose from the ashes.
哺乳动物
The mammals.
与恐龙相比 它们只是历史上的一个注脚
Under the dinosaurs, they had been a mere footnote in history.
如果没有小行星撞击
Without the asteroid strike,
这些幸存者都不可能有机会统治世界
none of these survivors would have had a chance to rule.
从大规模灭绝的灾难中
From the cataclysm of the mass extinction
诞生了这个多样而奇妙的生命群体
came this new multitude of life in all its wondrous variety...
它们全都完美地适应了生命的挑战
...all perfectly adapted to the challenges of life.
努力保护并养育幼崽
The struggle to protect and raise one's young,
寻找食物
to find food,
繁育后代
and to breed.
角色阵容也许已经改变
The cast of characters may have changed,
但关键因素依然相同
but the essentials remain the same.
水与来自太阳的能量
Water and the energy from the Sun
数十亿年如一日 持续支撑着生命
continue to support life, just as they have for billions of years.
即使在今天 生命法则依然适用
Even today, the rules of life still apply.
适者生存
Only the best adapted will win through.
竞争推动适应
Competition drives evolution.
快速变化的星球引发混乱
And a rapidly changing planet causes chaos.