The world’s largest organism - Alex Rosenthal

翻译人员: C Cheng 校对人员: Yolanda Zhang

This is Goliath, the krill.

这是歌利亚，一只磷虾。

Don’t get too attached.

不要对它太迷恋了。

Today this 1 centimeter crustacean

今天，这只 1 厘米长的 甲壳类动物

will share the same fate as 40 million of his closest friends:

将会与它 4000 万的亲密 朋友们遭受同样的命运：

a life sentence in the belly of the largest blue whale in the world.

在世上最大的蓝鲸的 肚子里囚禁终生。

Let’s call her Leviatha.

让我们称她为利维坦。

Leviatha weighs something like 150 metric tons,

利维坦重约 150 吨，

and she’s the largest animal in the world.

是世界上最大的动物。

But she’s not even close to being the largest organism by weight,

但她还远算不上是最重的生物体。

which is estimated to equal about 40 Leviatha’s.

后者的重量大约相当于 40 只利维坦。

So where is this behemoth?

那么这只巨兽在哪里呢？

Here, in Utah.

这里，在犹他州。

Sorry, that’s too close.

对不起，离得太近了。

Here.

这里。

This is Pando, whose name means “I spread out.”

这是潘多；名字意为 “我分散开来”。

Pando, a quaking aspen, has roughly 47,000 genetically identical clone trunks.

它是一种白杨，拥有大约 47000 枝基因相同的克隆树干。

Those all grow from one enormous root system,

这些全部都从同一个 庞大的根茎系统生长出来。

which is why scientists consider Pando a single organism.

这就是什么科学家们 认为潘多是一个单一的生物体。

Pando is the clear winner of world’s largest organism by weight—

潘多无疑是世界上最重的生物体——

an incredible 6 million kilograms.

600 万公斤的重量 令人难以置信。

So how did Pando get to be so huge?

那么，潘多何以变得如此巨大？

Pando is not an unusual aspen from a genetic standpoint.

从基因角度来看，潘多 并不是一种不寻常的杨树。

Rather, Pando’s size boils down to three main factors:

确切地说，潘多之所以拥有 这样的规模，要归结于三个主要因素：

its age, its location, and aspens’ remarkable evolutionary adaptation

它的年龄、生长地点， 和杨树非凡的

自我克隆的进化适应性。

of self-cloning.

So first, Pando is incredibly expansive because it’s incredibly old.

首先，因为极其古老， 所以潘多的分布极其辽阔。

How old exactly?

到底有多古老呢？

No one knows.

没人知道。

Dendrochronologist estimates range from 80,000 to 1 million years.

年轮学家估计它的年龄 在 8 万到 100 万年之间。

The problem is, there’s no simple way to gauge Pando’s age.

问题就在于，没有用来测量 潘多年龄的简单方法。

Counting the rings of a single trunk will only account for up to 200 years or so,

计算单一树干的年轮 只能算到 200 年左右；

as Pando is in a constant cycle of growth, death, and renewal.

而同时，潘多处在生长、 死亡，和更新的持续循环中。

On average, each individual tree lives 130 years,

每棵树平均会生长 130 年，

before falling and being replaced by new ones.

之后才会倒下，被新的树所取代。

Second: location.

其次，地点。

During the last ice age, which ended about 12,000 years ago,

最后一次冰川纪大约 结束于 12000 年前。

glaciers covered much of the North American climate

在这期间， 冰川覆盖了北美大部分

friendly to aspens.

适于白杨生长的气候区。

So if there were other comparably sized clonal colonies,

所以，如果还曾有过其它 规模类似的克隆植物群的话，

they may have perished then.

它们很可能都在那时消亡了。

Meanwhile, Pando’s corner of Utah remained glacier-free.

然而，潘多所在的 犹他州的一角却没有冰川。

The soil there is rich in nutrients that Pando continuously replenishes;

那里的土壤富含养料， 而潘多又在对其不断补充；

as it drops leaves and trunks,

当它的叶子和树枝掉落时，

the nutrients return to nourish new generations of clones.

营养返回土壤，以滋养 新一代的克隆植株。

Which brings us to the third cause of Pando’s size: cloning.

这就将我们引向了潘多形成 如今规模的第三个原因：克隆。

Aspens are capable of both sexual reproduction—

白杨既可以有性繁殖——

which produces a new organism—

产生出一个新的生物体——

and asexual reproduction— which creates a clone.

也可以进行无性繁殖—— 创造一棵克隆植株。

They tend to reproduce sexually when conditions are unfavorable

当条件不利时， 它们倾向于有性繁殖，

and the best strategy for survival is to move elsewhere.

而且最有利于生存的 策略是迁移到其它地方。

Trees aren’t particularly mobile, but their seeds are.

树木并不具有特别的可移动性， 但是它们的种子可以。

Like the rest of us, sexual reproduction is how Pando came into the world

与我们一样，有性繁殖是潘多 在几十万或者几百万年前

in the first place all those tens or hundreds of thousands of years ago.

最初来到世上的方式。

The wind or a pollinator carried pollen from the flower of one of its parents

风或者传粉的昆虫把花粉 从亲本植株中的一棵带到另一棵，

to the other, where a sperm cell fertilized an egg.

在那里精子细胞使卵子受精。

That flower produced fruit, which split open,

那朵花结出果实， 果实再破裂开来，

releasing hundreds of tiny, light seeds.

释放出大量轻微的种子。

The wind carried one to a wet spot of land in what is now Utah,

风把一粒种子带到了 现今犹他州的一块湿地上，

where it took root and germinated into Pando’s first stem.

它在那里生了根，发了芽， 长成了潘多的第一枝主杆。

A couple of years later, Pando grew mature enough to reproduce asexually.

几年后，潘多生长成熟， 足以进行无性繁殖。

Asexual reproduction, or cloning,

无性生殖，或者克隆，

tends to happen when the environment is favorable to growth.

往往发生在 环境适于生长的时候。

Aspens have long roots that burrow through the soil.

白杨有着钻透土壤的长根茎。

These can sprout shoots that grow up into new trunks.

它们可以抽芽，长出新的树干。

And while Pando grew and spread out, so did our ancestors.

在潘多生长蔓延的时候， 我们的祖先也做着同样的事情。

As Hunter-gatherers who made cave paintings, survived an ice age,

作为狩猎采集者，他们创造了 洞穴画，活过了冰川纪，

found their way to North America, built civilizations in Egypt and Mesopotamia,

设法到达了北美洲，在埃及和 美索不达米亚创造了文明，

fought wars, domesticated animals, fought wars, formed nations,

发动战争，驯服动物， 再发动战争，建立了国家，

built machines,

制造了机器，

and invented the internet, and always newer ways to fight wars.

还发明了国际互联网，而且 总是能找到新的战争形式。

Pando has survived many millennia of changing climates and encroaching ice.

经过几千年的气候变化 和冰川侵蚀，潘多存活了下来。

But it may not survive us.

但是，它也许敌不过人类的活动。

New stems are growing to maturity much more slowly than they need to

新主杆的成熟速度大大慢于

in order to replace the trunks that fall.

它所需要的用以 更新倒落枝干的速度。

Scientists have identified two main reasons for this.

为此，科学家已经 确定了两个主要原因：

The first is that we’ve deprived Pando of fire.

首先，潘多失去了 发生林火的机会。

When a fire clears a patch of forest, Aspen roots survive,

当大火清除了一片森林时， 白杨的根却可以存活下来，

and send shoots bursting up out of the ground by the tens of thousands.

而且，成千上万的新枝会破土而出。

And secondly, grazers like herds of cattle and mule deer—

第二，食草动物，如成群的 牛和美洲黑尾鹿——

whose natural predators we’ve hunted to the point of local elimination—

它们的天敌已经被我们猎杀 到几近局部灭绝的地步——

are eating Pando’s fresh growth.

会啃食潘多新生的枝桠。

If we lose the world’s largest organism, we’ll lose a scientific treasure trove.

如果我们失去了世上最大的生物体， 那么我们将失去一个科学宝藏。

Because Pando’s trunks are genetically identical,

因为潘多的枝干基因相同，

they can serve as a controlled setting for studies

所以它们可以作为一个受控环境，

on everything from the tree microbiome

用来研究所有从树的微生物群

to the influence of climate on tree growth rates.

到气候对树木生长率的 影响的相关课题。

The good news is, we have a chance to save Pando,

好消息是，我们有机会拯救潘多；

by reducing livestock grazing in the area

这要通过减少 在这一区域内放牧的牲畜，

and further protecting the vulnerable young saplings.

和进一步保护脆弱的幼树来实现。

And the time to act is today.

行动的时间就在今日,

Because as with so many other marvels of our natural world,

因为，同自然界中 许多其它奇迹一样，

once they’re gone it will be a very, very long time before they return.

一旦消失，它们的回归就会 需要很长很长的时间。