我们星球上的生命（2023）

它们古老对手的蜕皮
The discarded skin of their ancient adversary.
蛇
The snake.
蛇的进化时间 与第一批真正的哺乳动物大致相同
Snakes evolved around the same time as the first true mammals.
它们失去了爬行动物祖先的四肢
They lost the arms and legs of their reptilian ancestors
并发展出流线型身体
and developed a streamlined body...
使它们完全适应了在洞穴中捕猎
making them perfectly adapted to hunting in burrows
以及悄无声息地 在下层灌木丛中追捕猎物
and silently pursuing their prey through the undergrowth.
但是哺乳动物幼崽并非完全无助
But young mammals aren't entirely helpless.
它们有母亲来照顾自己
They have their mothers to look after them.
它发现危险
She spots the danger...
提高警惕
...and raises the alarm.
但是蛇直扑幼崽
But the snake is headed straight for her youngster.
多亏有父母的招呼
Thanks to parental care,
这次哺乳动物胜出
in this instance, the mammals win out.
但是爬行动物有耐心
But reptiles have patience.
它们从恐龙时代初期 就开始玩这个游戏
They've been playing this game since the dawn of the dinosaurs.
随着哺乳动物的繁荣发展
And as mammals prospered,
以之为食的蛇也兴盛起来
so too did the snakes that fed on them.
如今世界上有超过3000种蛇
Today, there are more than 3,000 species of snake.
凭借其蜿蜒的身体
With their sinuous bodies...
发达的肌肉
packed with muscle...
它们进化出了 适应地球上几乎每一个栖息地的能力
they've evolved to exploit almost every habitat on Earth.
甚至包括海洋
Even the oceans.
与许多爬行动物一样
Like many reptiles,
它们的皮肤可以提供完美的伪装
their skin can offer perfect camouflage.
再配上毒液
When paired with venom,
效果致命
the effect can be deadly.
但是哺乳动物与蛇的军备竞赛 已经开展超过一亿年
But mammals have acquired some extraordinary defenses...
在这个过程中
having been locked in an arms race with snakes
哺乳动物获得了非凡的防御能力
for more than a hundred million years.
侧进蛇
The sidewinder snake.
它会等待经过的热痕迹 一等就是几个小时
It will wait for hours at a time for signs of passing heat.
来自小型温血哺乳动物身上的热痕迹
Heat that comes from small warm-blooded mammals.
但是更格卢鼠可不是普通的啮齿动物
But kangaroo rats are not your average rodent.
它们发展出一项独特技能
They've developed a unique skill
与其名称非常相称
befitting of their name.
冷血的侧进蛇耐心地等待
The cold-blooded sidewinder bides its time.
它可以几周不进食
It can go weeks without eating...
只在等待出击
just waiting to strike.
瞬间的反应
Split-second reactions...
对上无比的耐心
versus incredible patience.
这些都是在永恒的生死博弈中
These are the extremes that can evolve
进化出的极端情况
in the eternal game of life and death.
（6600万年前）
经过1.5亿年的恐龙统治
After 150 million years of dinosaur rule,
各大♥陆♥几乎漂移到了今天所在的位置
the continents had shifted almost to where they are today.
在此过程中 创造出许多新的环境
Along the way, they had created so many new environments
以至于恐龙取得了前所未有的成功
that the dinosaurs had become more successful than ever before.
在它们脚下
Beneath their feet
生活着 我们现在所认识的所有主要动物群
lived all the major animal groups that we recognize now.
有亿万年中坚持下来的王者
Dynasties from throughout the ages.
有来自另一个时代的生存者
Survivors from another era.
也有最近才崭露头角的角色
Along with those that had more recently come to the fore.
但所有这些动物 都被统治者恐龙逼到边缘
But all of them forced to the margins by the dominance of the dinosaurs
尤其是那个统治一切的标志性动物
and the one iconic animal that ruled over them all.
长13米
Thirteen meters long,
重9吨♥
weighing nine tons...
难怪地球史上最著名的捕食者
...it's no wonder that the most famous predator in the history of life on our planet
是霸王龙
is Tyrannosaurus rex.
但它并不孤单
But he's not alone.
又一只霸王龙
Another T. rex.
两只霸王龙互相打量着对方
The two size each other up.
霸王龙经常会为领地而战
Tyrannosaurs will often fight for territory...
并且不会拒绝同类相食
and are not above cannibalism.
但这只雄龙还有其它念头
But there's something else on this male's mind...
因为它面对的是一只雌龙
...for he has found a female.
这意味着要展示出自己最出色的本领 以赢得雌龙的青睐
And that means showing off his best moves to win her over.
但如果判断错误
But misjudge the approach,
这场约会就会瞬间结束
and this date could be over in seconds.
它迷人的动作
His mesmerizing movement
和深沉的低吼
and deep romping calls
似乎得到了良好的回应
seem to be eliciting the right response.
对方模仿起了它的求爱舞蹈
And she mirrors his courtship dance.
但最终的信任标志 是暴露出自己的脖子
But the ultimate sign of trust is exposing his neck.
双方一起抬起脖子
Rising together,
确定了关系
they cement their bond.
1.5亿年间
For 150 million years,
恐龙统治着地球
dinosaurs ruled the planet.
如果它们继续统治下去
Who knows what new heights
能达到何种新的高度 谁都不知道
they might have reached if their reign had continued.
但在生命的故事中
But in the story of life...
一切都不是永恒的
...nothing lasts forever.