‎NETFLIX 原创纪录片系列
‎地球 数百万物种的家园
The Earth, home to millions of species.
‎但地球之外…生存着什么？
But what might live... beyond?
‎天文学家已经在我们太阳系外 ‎发现了数千个行星
Astronomers have discovered thousands of planets
outside our solar system.
‎他们相信还有数万亿个未被发现
They believe there are trillions more.
‎即使一小部分行星上存在生命
If life exists on only a fraction of them,
‎那么宇宙一定充满生机
then the universe must be... alive.
All living things have the same needs.
‎所有生物都有同样的需求
‎进食…
To feed...
‎繁衍…
reproduce...
and evolve.
‎和进化
‎通过将地球生物的规律
By applying the laws of life on Earth
‎应用到宇宙中的其他地方
to the rest of the universe...
‎我们可以想象
it's possible to imagine what could live...
‎外星世界
‎会有什么生存
on alien worlds.
‎（美国加州里克天文台）
‎天文学家把我们太阳系之外的行星 ‎称为系外行星
Planets beyond our solar system are known to astronomers as exoplanets.
‎他们距地球都有数万亿公里
They are all trillions of miles from Earth.
‎然而 生命的微弱信号还是可能通过 ‎它们环绕的恒星
And yet, it might be possible to detect a faint signature of life,
‎发出来的光被侦测到
from the light of the stars they orbit.
Every star is sending to us light of all different colors.
‎每颗恒星都向我们发送不同颜色的光
‎所以如果我们可以利用望远镜 ‎接收这种光
So, if we can catch that light in our telescope
‎利用仪器将光分散成彩虹
and put it through an instrument that spreads the light out into a rainbow,
‎然后观察这个彩虹的丰富细节
and we look in great detail at that rainbow,
‎我们能发现这颗恒星大气中
we will find the chemical fingerprints
‎各种元素的化学指纹
of the elements in the atmosphere of that star.
‎这是我们利用望远镜捕捉到的一颗
This is one of those rainbows captured by the telescope of a distant star
‎约12光年之外称为天仓五的 ‎遥远的恒星的彩虹
about 12 light-years away, the star Tau Ceti.
‎我们能看到这些暗线 ‎这是恒星大气中氢元素留下的
We can see these dark lines, like from hydrogen in the star's atmosphere.
‎这里我们能看到镁元素留下的 ‎具有特征性的三条线
Down here, we see these three characteristic lines of magnesium.
‎所以 这就是这颗恒星的大气
So, this is the atmosphere of the star,
‎但我们想做的是
but what we wanna do is catch light
that passes through the atmosphere of an exoplanet,
‎捕捉穿过系外行星大气的光线
‎以同样的方式捕捉系外行星 ‎大气元素的指纹
to capture the chemical fingerprint of that atmosphere in exactly the same way.
‎2012年 在我们自己的太阳系 ‎这种指纹可以被观测到
In 2012, this sort of fingerprint
was visible in our own solar system.
‎当金星从太阳前面飞过
When Venus passed in front of the sun,
‎留下了阴暗的背影
it was silhouetted against it.
For a moment, a tiny halo appeared, the atmosphere of Venus.
‎一瞬间 一个微小的光环出现了 ‎这就是金星的大气层
‎这就是天文学家寻找的一片光线
It's this sliver of light astronomers are looking for.
‎如果他们能分析 ‎遥远的系外行星的大气层
If they can analyze the atmosphere of distant exoplanets
‎也就是它们背对遥远的恒星 ‎留下的剪影
silhouetted against distant stars,
‎天文学家有可能找到生命的证据
they might find proof of life.
‎我们仔细思考过什么会是生命的信号
We've thought very carefully about what the signs of life will be.
‎于是我们四处寻找 ‎我们查看大气层里有什么
So we look around and we look at what's in the atmosphere
‎能从数光年之外远程侦测到
that could be remotely detectable from light-years away.
‎最终归结为同一种气体：
And it always leads us back to the same gas.
‎氧气
Oxygen.
‎我们的大气层中50%到70%的氧气
50 to 70 percent of oxygen in our atmosphere
‎其实来自海洋…
is actually coming from the ocean...
‎海洋是地球的肺
which is the lungs of planet Earth.
‎促使海洋中巨大的海带生长的过程
The process that drives the growth of the giant kelp in the oceans,
and, in fact, all the forests that we see on the land,
‎正如我们在陆地上看到的森林一样
‎都是光合作用
is photosynthesis.
‎光合作用最令我感兴趣的在于
What interests me most about photosynthesis
‎其排出的废料
is the waste product that gets tossed away,
and that's the oxygen that goes into the atmosphere.
‎也就是进入大气层的氧气
‎我们认为我们大气中几乎所有的氧气 ‎都是地球上的生物
We think that almost all of the oxygen in our atmosphere
is produced by photosynthesis,
‎通过光合作用制造的
by life here on planet Earth.
‎如果你看到某个星球上氧气充沛
If you see it in abundance,
‎你就知道那里充满生机
you know that the planet is a living world.
‎在宇宙中亿万个世界里
Among trillions of worlds out there,
‎那些有更多氧气的星球 ‎更有机会支撑生命
those with more oxygen are more likely to sustain life.
‎想象一下…一颗类似地球的行星 ‎绕着不止一颗恒星…
Imagine... a planet like Earth
orbiting not one star...
‎而是两颗恒星旋转
but two.
‎这就是伊甸
This is Eden.
‎双太阳的光给光合作用提供了能量
The light from its twin stars powers photosynthesis...
‎将氧气大量排放到大气层中
pumping oxygen into the atmosphere...
‎供生命繁衍生息
allowing life to thrive.
‎食草动物以地面的菌类为食
Grazers feed on low-lying fungus...
‎但它们随时对危险保持警惕
...but they're constantly alert to danger.
‎树林的冠层是掠食者的家园
The canopy is home to predators...
‎进化让它们完美地适应了树上的生活
...perfectly evolved to live among the trees...
‎等待出击的时机
...waiting for their moment to strike.
- -
‎在地面上 食草动物有优势
On the ground, the grazer has the edge.
‎在追逐中 它们更快
It's faster in a chase.
‎但掠食者进化出一种特别的武器
But the predator has evolved a special weapon.
‎这次 食草动物得以逃脱
This time, the grazer escapes...
‎掠食者保存了其能量
and the predator conserves its energy.
‎在任何星球 能量都是珍贵的
On any planet, energy is precious.
‎恒星的光几乎是无限的资源
Starlight is a virtually infinite source.
‎但问题在于 ‎如何将这种光转变为生命
But the trick is to turn that light into life.
‎我们在热带雨林中
We are in the tropical rainforest.
‎这里比地球的其他地方 ‎有更多种植物和动物
There are more types of plants and animals here than anywhere else on Earth.
‎（哥伦比亚 绿洲公园）
‎树木和其他植物吸收太阳的能量
The trees and plants are soaking up the sun's energy.
‎通过光合作用的魔法 ‎它们将太阳光转化成葡萄糖
By the magic of photosynthesis, they convert sunlight into glucose energy,
‎也就是糖
in other words, sugar.
‎你能看到 也可以尝到
You can see it and even taste it.
‎你可以切实品尝到来自太阳的能量
You can actually taste the energy from the sun.
‎植物就像是电池
Plants act like batteries,
‎捕获太阳能变成葡萄糖
capturing the sun's energy as glucose.
‎食草动物吃植物
Herbivores eat plants.
‎食肉动物吃食草动物
Carnivores eat herbivores.
‎食物链的每一个环节
Every link in the food chain
‎都依赖于这种葡萄糖能量的转移
depends on the transfer of this glucose energy.
‎在这个丛林里
And in this forest,
‎有一种动物对葡萄糖的需求 ‎永远无法满足
one animal can't get enough of the stuff.
‎它们就是蜂鸟
The hummingbird.
‎每秒钟 蜂鸟能煽动超过100次翅膀
Hummingbirds can move their wings over a hundred times a second.
‎你能感觉到它们为了停留在空中 ‎需要耗费多少能量
You can feel how much energy they are spending just by being there.
‎这种疯狂的活动
This frenzy of activity
‎是通过富含葡萄糖的花蜜提供能量的
is fueled by glucose-rich nectar.
‎从正面 这个设备看起来像一朵花
This is a device that from the front, it looks like a flower,
‎于是蜂鸟会过来采食
so a hummingbird comes and it feeds from it.
‎来了一只
And there is one.
‎它来来回回 拜托 你能行的
It's going back and forth. Come on, you can do it.
Uh... Okay, so now, he's drinking.
‎好了 他现在在喝蜂蜜
‎这个装置能测量蜂鸟采食的花蜜
The device measures the nectar the bird is drinking
‎以及它呼吸的氧气
and the oxygen it is breathing.
‎我们通过花蜜计算摄入的能量
We calculate the energy intake from the nectar
‎通过氧气计算释放的能量
and the energy output from the oxygen
‎我们能精确计算出 ‎蜂鸟使用了多少能量
and we can calculate very accurately how much energy the bird is using.
‎悬在半空的蜂鸟 ‎用令人难以想象的速度消耗着氧气
A hovering hummingbird consumes oxygen at an incredible rate.
‎比奥运会短跑运动员 ‎还要快超过十倍
Ten times faster than an Olympic sprinter.
‎越多氧气进入细胞 ‎葡萄糖就能燃烧得越快
The more oxygen it can get into its cells, the faster it can burn glucose,
‎从而释放葡萄糖内的能量
which unlocks the energy within.
‎在地球上 大气层中21%是氧气
On Earth, 21 percent of the atmosphere is oxygen...
‎为我们身边多样的生物提供能量
fueling the diversity of life around us.
‎（大气层中的氧气）
‎在伊甸 氧气要比在地球上多10%
On Eden, there's ten percent more oxygen than on Earth...
‎于是这里的生命会更加多样
so life here can be more diverse...
‎更加有活力
more energetic...
‎更具有竞争性
more competitive.
‎夏天是食草动物的繁殖季节
Summer is breeding season for grazers.
‎由于它们一直害怕掠食者 ‎所以它们并不会花时间去找配偶
Always fearful of predators, they don't spend time finding a mate.
‎而是产出像蠕虫一样的卵
Instead, they produce worm-like spawn.
‎每个卵必须和另一个卵融合
Each needs to fuse with another
‎才能形成胚胎
to create an embryo.
‎它们还会形成蛹作为保护
For protection, they form a cocoon.
‎悬挂在半空中 胚胎可以生长
Suspended above the ground, the embryos can grow,
‎避开掠食者
away from predators.
‎在我们地球上 ‎死亡威胁是生命进化的
Here on Earth, the threat of death is a huge factor
‎一个重要因素
in the evolution of life.
‎捕食无所不在
Predation is everywhere.
‎所有生物都有
There's not an organism out there
‎被另一种生物吃掉的风险
that doesn't run the risk of being eaten by another organism.
‎我感兴趣的方面在于 ‎捕食如何影响繁殖
The aspect that I'm interested in is how predation shapes reproduction.
‎（特立尼达 阿里马谷）
‎它们会到这里来
They're gonna be comin' in here.
‎这条河流非常适合研究孔雀鱼
This river is perfect for studying guppy fish...
‎以及它们繁殖的模式
and their patterns of reproduction.
- Here. Here's another male. - Yeah, yeah.
‎-是 ‎-另一条雄鱼
‎这里的环境很友好
This is an easy neighborhood.
‎孔雀鱼只和另一个鱼的物种 ‎在这里生存
Here, guppies live with only one other species of fish,
‎这种鱼很少会吃孔雀鱼 ‎或者骚扰它们
and it's a fish that rarely eats guppies or harasses guppies.
They can swim wherever they want without any risk of somebody trying to eat them.
‎孔雀鱼可以游到任何地方 ‎而不用担心被吃掉
‎-好 抓到了 ‎-抓到了
-Oh, right. There you go. All right. - Here we go.
‎我们捕到一些孔雀鱼 ‎我们这里有五条
Here we have some babies that we just caught. We have five of them here.
‎你也许觉得它们很小 ‎但作为新诞生的孔雀鱼
They may look small to you, but that's really big for a newborn baby guppy.
‎它们已经很大了
‎这里的孔雀鱼把大量的精力 ‎投入在相对较少的后代身上
The guppies here invest a lot of effort
in relatively few offspring.
‎而在下游 情况就完全不同了
Downstream, it's a different story.
‎好了
Okay!
Wow.
‎哇
This boulder is a natural barrier, dividing the river.
‎这块巨石是个自然屏障 ‎把河流分成两部分
‎在这之下 潜伏着危险
Below it lurks danger.
‎孔雀鱼在这里的生活 ‎差不多是一种逃亡生活
A guppy life down here is pretty much like the life of a fugitive.
‎你随时都在逃避捕食者 ‎如果一条孔雀鱼在这里游
You're always on the run from predators.
If a guppy were to swim out here...
‎它的生命不能延续多久
it wouldn't last a second.
‎孔雀鱼唯一的防御手段 ‎就是繁殖很多后代
The only defense the guppies have
is to produce lots of offspring,
‎以期待一部分能活到成年
in the hope that some will survive to adulthood.
‎好了 我这里有两条来自上游的幼鱼 ‎那里没有捕食者
Okay, I've two babies from up there, where guppies live without predators,
‎还有四条来自下游的 这里有捕食者
and four from down here, where guppies live with predators.
‎它们个头的差别非常大
There's a dramatic difference in size.
‎这里幼鱼的个头
Those that are from here are much, much smaller
‎要比来自屏障上游的小很多
than the ones that I caught above the barrier.
‎无论母鱼怎么做 ‎她们活到未来的机会都不大
Moms don't have a big prospect of living to the future, no matter what they do.
‎所以在这里最佳的策略就是 ‎繁殖很多个头小的幼鱼
So the best strategy down here is to make many small babies.
- -
‎孔雀鱼进化出两种不同的繁殖方式
The guppies have evolved two different ways of breeding.
Having a few large babies...
‎产出为数不多的大个头的幼鱼…
‎或产出很多小个头的幼鱼
or lots of small ones.
‎决定因素在于捕食者的威胁
The deciding factor is the threat from predators.
‎如果你会成为猎物 你活不了很久
If you're one of the prey items, you're gonna die young,
‎那你最好活得快一些
so you better live fast.
‎你最好努力繁衍后代 ‎否则你就会灭绝
You better put a lot into having babies, because if you don't, you'll go extinct.
‎这种策略适用于任何星球
Such a strategy would apply on any planet
‎只要那里有一个物种捕食另一个物种
wherever one species preys on another.
‎在伊甸 食草动物通过进化 ‎繁殖变得很快
On Eden, the grazers have evolved to breed fast.
‎它们尽快产出尽量多的后代
They produce as many offspring as quickly as possible...
‎以确保物种能够延续
to ensure the survival of the species.
‎但在丛林里 它们没有真正的安全
But in the forest, they're never truly safe.
‎随着夏天‎的‎结束
As summer ends, the fungi grow orange-colored fruit...
‎菌类长出橘红色的果实
‎这会吸引食草动物
which attract grazers.
- -
‎果实里的孢子会散播感染
Spores within the fruit spread an infection.
‎现在 掠食者攻击时
Now, when predators attack,
infected grazers don't run.
‎受感染的食草动物不会跑
‎它们已经失去了害怕的本能
They've lost their fear instinct.
‎这顿食物来得很轻松
It's an easy meal...
‎但却是有毒的
but a poisonous one.
‎菌类利用了食草动物 ‎感染并杀死了掠食者
The fungi have used the grazers to infect and kill the predators.
‎（坦桑尼亚 大裂谷）
‎这种复杂的关系 ‎在地球的物种之间也存在
Such complex relationships between species exist on Earth...
‎但并不都是致命的
but not all are so lethal.
‎哈扎人过着原始生活 靠土地过活
The Hadza are hunter-gatherers, living off the land.
‎我叫帕兰戈
My name is Palango.
‎作为一个男人 我的职责是狩猎
As a man, my job is to hunt.
‎我总是带着弓和箭
I always carry a bow and arrow
‎作为保护
for protection...
‎因为树丛里
because the bush
‎有很多危险的动物
has many dangerous animals.
‎有一种高卡路里的食物备受推崇
One high-calorie food is prized above all else.
‎它就是蜂蜜
Honey.
‎但是寻找新鲜蜂蜜非常困难
But finding fresh honey is difficult.
‎每次换季 蜜蜂会在不同的地方筑巢
The bees move their nests from season to season.
‎于是 哈扎人找来帮忙的
So the Hadza call on help.
Honeyguides are very clever birds.
‎响蜜鴷是一种非常聪明的鸟
‎它们知道蜂蜜在哪儿 并会带你去
They know where honey is, and they will take you there.
‎它会发出一种特别的叫声…
She makes a special cry...
...and I whistle back.
‎而我吹口哨回应
If I follow her, she will lead me directly to the honey.
‎只要我跟着它 ‎它会把我直接带到有蜂蜜的地方
- -
‎响蜜鴷果然名不虚传
The honeyguide has lived up to its name.
‎把狩猎者带到一棵猴面包树上的蜂巢
It's led them to a bees' nest in a baobab tree.
‎狩猎者需要这种鸟来找到蜜蜂
The hunters need the bird to find the bees.
‎响蜜鴷需要狩猎者来获取蜂蜜
And the bird needs the hunters to access the honey.
‎响蜜鴷带我们找到蜜蜂
The honeyguides take us to the bees.
‎但蜜蜂具有进攻性
But the bees are aggressive.
‎所以 它需要我们的帮助
So she needs our help.
‎爬上猴面包树
Climbing up a baobab tree...
‎非常困难 也非常危险
is very hard and dangerous.
‎有一次我摔了下来
One day I fell.
‎我们用烟把蜜蜂熏晕
We use smoke to get the bees drunk
‎把它们赶出蜂巢
and chase them out of the nest.
‎风险是值得的
The risk is worth it.
Fresh, rich, honey.
‎新鲜浓烈的蜂蜜
‎帕兰戈给了鸟它该得的一份
Palango makes sure the bird gets its share.
It's a win-win situation.
‎这是双赢
‎物种之间建立的一种 ‎被称为共生的复杂的关系
A complex relationship between species
is known as symbiosis.
‎生态系统越是丰富 关系就越复杂
The richer the ecosystem, the more complex the relationship.
‎在伊甸 ‎一种致命的三向共生关系演化出来
On Eden, a deadly three-way symbiosis has evolved...
centered around the fungi.
‎核心是菌类
- -
‎首先 它们让食草动物吃
First, they feed the grazers.
- -
Then, they infect them...
‎让它们受到感染
‎再去毒死掠食者
to poison the predators.
‎菌类这样做的目的 ‎是为了它们下一代的成长
And the fungi do all this to grow their next generation...
‎它们下一代从掠食者的尸体得到营养
which feeds on the bodies of the dead predators.
On Earth, fungi play a crucial, but invisible role
‎在地球上 菌类对森林的生机 ‎起着关键但看不见的作用
in the life of any forest,
‎在幕后
behind the scenes.
‎（苏格兰 罗希姆丘奇森林）
So, I think most people think the first complex life on our planet
‎我觉得绝大部分人以为 ‎我们星球上首先出现的复杂生命
‎是诸如昆虫 甚至也许是恐龙
was something like insects, or maybe even the dinosaurs.
‎但事实上 比这早数万亿年
But, actually, hundreds of millions of years before that,
‎第一种真正的复杂的 ‎多细胞生物是这些东西
really the first complex multicellular organisms were these things.
‎菌类
Fungi.
‎我们已知至少有14万个物种
We know of at least 140,000 species,
‎但这可能不到真正总数的百分之十
but that's likely to be less than ten percent of the real total.
‎仅仅在这个森林里 也许就有数千种
There's probably thousands of different fungal species
‎不同的菌类物种
just in this forest alone.
Okay, so we've actually got three mushrooms here
‎好 我们这里有三个蘑菇
and you can actually see these dotted all throughout the forest.
‎你能看到这种蘑菇分布在整个森林里
But what's amazing is that these mushrooms
‎但神奇的是
‎你看到的这些蘑菇只是冰山一角
are really just the tip of the iceberg.
‎当我们揭开地层表面
When we look below the surface,
‎绝大部分的菌类是这些
most of the fungus is actually in these little... tiny little threads,
‎遍布在土壤里的细丝
that go all throughout the soil.
‎这种东西称为菌丝体
And this is called the mycelium,
and it connects all of the other mushrooms in this area.
‎它连接着这个地区所有的蘑菇
‎这种遍布于土壤中的微小的菌类
There can be tens of kilometers of these tiny microscopic fungi
‎蔓延数十公里
spreading throughout the entire soil.
‎树木的生存依赖于这些纤维
The tree needs those fibers to survive,
‎因为树木能从大气里获取碳元素
because the tree can capture carbon from the atmosphere,
‎为菌类提供碳元素
and it provides that carbon to the fungus.
‎同时 菌类能从土壤中获取氮和磷
In contrast, the fungi access nitrogen and phosphorus from the soil,
‎以交换碳元素
which they give in exchange for that carbon.
‎所以这真的是一种 ‎对两种生物都有利的互利共生
So, really, it's a mutualism that benefits both of the organisms.
‎这种菌丝系统最独特的地方
Possibly the most extraordinary thing
‎在于它们彼此的连接是何等紧密
about this mycelial system
is just how connected it is.
‎粘附在这棵树的树根的菌类
So, the fungi that are attached to the roots of this tree
‎也粘附在那棵树的树根上
will also be attached to the roots of that tree,
‎还有那边的那棵树
and that tree over there,
‎而它们又通过同样的菌丝体 ‎和邻近的树相连
and they will also be connected to their neighbors
‎菌丝体从一棵树连接到另一棵树
via the same mycelial system
that is really going tree to tree to tree.
The mycelial network is like a circuit of wires and nodes
‎菌丝体网络就像 ‎由电线和节点组成的电路
‎借此信息得以传播
through which information can flow.
‎通过它
And with it, fungi can maintain the forest.
‎菌类可以维护森林
‎如果那边有一棵树正在死去
So, if we have one tree over there that's dying,
‎菌类会将更多的养分分配给那棵树
it might reallocate more nutrients towards that tree,
‎这样那棵树能生长得更好
so that the tree can do better
and, as a result, the fungal system does better.
‎结果 菌类系统也能生长得更好
‎同样的 ‎菌类网络的某个部分出了问题
Similarly, if there's disturbance at some part of the fungal network,
‎养分就会被移除到其他地方
it will remove nutrients away
‎这样可以最大程度地减少 ‎问题造成的影响
so that it can minimize the impact of that disturbance.
‎正是这些看不见的生态系统工程师
It's these invisible ecosystem engineers
‎保持整个系统 ‎以非常健康的方式运作
that are keeping the entire system functioning in a really healthy way.
‎这种系统被称为木万维网
This system has become known as the Wood Wide Web,
‎听起来像是个笑话
and it sounds like a bit of a joke,
‎但其功能和因特网并没有什么不同
but, really, it doesn't function so differently from the internet,
‎保持森林系统中所有生物连接在一起
keeping all of the organisms connected in the forest system.
‎这种过程存在于
This process is happening all across the planet,
‎整个星球上 ‎我们能想到的每一个生态系统
in every ecosystem we can imagine.
‎如果我们有机会找到某个外星星球 ‎拥有茂盛的生态系统
So, if we're gonna get a lush ecosystem on some alien planet out there,
‎我敢肯定 像这样的 ‎巨大的菌丝体系统一定是其基础
I bet you that it's underpinned
by something like this massive mycelial system.
- -
‎在伊甸 森林里的生活是一种
Life in the forests of Eden is a trade-off
‎发生在菌类、食草动物 ‎和掠食者之间的交换
between fungi, grazers and predators.
‎但还有一个更大的从天上来的力量 ‎参与其中
But there are greater celestial forces at play.
‎伊甸的季节比地球上更明显
Eden has stronger seasons than on Earth,
‎双太阳带来的光线和热度波动性更大
greater fluctuations of light and warmth from its twin stars.
‎随着冬季来临
As winter approaches,
‎幸存下来的捕食者跟着阳光
the remaining predators migrate...
‎迁徙到别处
chasing the light.
‎剩下的食草动物会死去
The remaining grazers die.
‎每年冬天都是如此
It's the same every winter.
‎阴暗的树林里万物不生
Nothing grows in the dark forest...
‎除了那些蛹里的胚胎
...except the embryos in their cocoons.
‎随着季节开始变换
Just as the season starts to change...
‎食草动物开始孵化
the grazers hatch...
taking their cue from the return of the twin stars.
‎它们是受到双太阳回归的影响
‎在地球上 生命也是一样的
On Earth, life does the same thing,
‎将季节作为时钟
using the seasons as a clock.
‎现在是盛夏
It's midsummer,
‎一年中日照时间最长的时候
the longest day of the year.
‎（美国 宾夕法尼亚州 ‎黄布里切斯河）
‎每年这个时候有大量飞蝇钓爱好者
There's a lot of fly fishermen out this time of year
‎因为每年在这个时候鱼儿很乐意咬钩
because this is the time of year that the fish are biting,
‎因为河里有充足的食物
because there is an abundant food source in the river,
‎食物来源都是这些蜉蝣的若虫
and that food source are all these guys, the mayfly nymph.
‎我们以为蜉蝣是在陆地上飞
So, we think of mayflies as flying around on the land with us,
‎但它们绝大部分的生命周期 ‎是在河流的底部度过的
but they spend the vast majority of their life cycle living down
‎它们在那里发育 长大
on the bottom of the river, developing, growing,
‎为每年的这一时候做准备
and it's all really building up to this one time in the year
‎到时候他们都会出来
where they're all going to emerge.
‎黄布里切斯河
Yellow Breeches River
‎汇流到萨斯奎汉纳河
feeds the Susquehanna.
‎在这些水下
Beneath these waters,
‎数百万的蜉蝣长成熟了 准备出来
millions of mayflies are primed and ready to go.
‎太阳一下山…
And when the sun sets, they emerge...
en masse.
‎它们成群涌现
‎好多虫子 好像不知道是从哪儿来的
There are just so many insects that seemingly came out of nowhere.
‎感觉像是外星生物入侵
It really almost feels like an alien invasion.
Mayflies live, at most, for two days.
‎蜉蝣最多活两天
‎在这两天中 它们必须找到配偶 ‎将基因传递下去
In that time, they must find a mate to pass on their genes.
‎它们只有一次机会 如果错过了
They have one shot, they have one chance, and if they miss it,
‎这只蜉蝣就没戏了
it's game over for that mayfly.
‎交配之后
Once they've mated,
‎雌性蜉蝣会回到河里产卵
the females return to the river to lay their eggs,
‎然后就死了
and then die.
‎这里的每一个白点都是一只蜉蝣
Each of these little white dots is a mayfly
‎它们成功回到河里产了卵
that successfully made it back to the water and has laid eggs.
‎它们成千上万随流而下
They are floating down by the thousands, by the hundreds of thousands.
‎它们开启了下一代
They have started the next generation
‎在接下来的一年继续重复
that will continue on and do this again next year
in this really precisely timed event.
‎这一精确按时出现的活动
‎季节的节奏
The rhythm of the seasons is always dictated
‎总是由行星相对恒星的倾角决定的
by the tilt of a planet towards its star.
‎地球的倾角是23.5度
Earth is tilted at an angle of 23-and-a-half degrees.
‎在伊甸 这一倾角是40度
On Eden, that angle is 40 degrees,
‎于是 更多阳光散布到 ‎星球上的更多表面
so more light spreads across more of the planet's surface.
‎越多阳光意味着越多生命
And more light means more life.
It's spring, and there's food to eat...
‎春天 食物充足
‎但新生的食草动物 ‎需要在掠食者回来之前
but the new grazers need to grow as fast as possible...
‎尽快成长
...before the predators return...
‎生命周期再次重复
and the life cycle repeats.
‎神奇的生物…
Wondrous creatures...
‎以葡萄糖为食…
fed by glucose...
‎由氧气提供能量…
powered by oxygen...
nourished by starlight.
‎受到阳光滋养
‎适用于伊甸的规律 ‎同样也可能适用于整个宇宙
What is true on Eden may be true throughout the universe...
that all life depends on the flow of energy.
‎即所有生命都依赖于能量的流转
‎在一个不同的世界 ‎生命会如何去适应？
How might life adapt on a different world,
‎那里居住着智慧生物
inhabited by intelligent beings,
‎它们足够智慧 ‎以至于能在群星之中
intelligent enough to make a new home...
‎建造新的家园
among the stars?
‎字幕翻译：张王华