Dead stuff: The secret ingredient in our food chain - John C. Moore

翻译人员: Jing Littlejohn 校对人员: Xiaoou Chen

If someone called you scum,

如果有人叫你废物，

you'd probably be offended,

你或许会觉得他冒犯了你。

but scientifically,

但从科学角度来看，

they might not be far off.

他们可能没完全说错。

Have you ever thought about

你可否想过

where your food comes from?

你每天吃的食物从何而来？

You might say it comes from

你或许会说这些食物来自

plants, animals, or even fungi,

植物、动物、或者真菌类植物，

but you'd probably rather not

但你可能不愿想到，

think about the rotting organisms and poop

腐烂的有机物和粪便

that feed those plants, animals, and fungi.

是植物、动物和真菌类植物的食物。

So really, you and most of the matter in your body

所以事实上， 你以及你的身体的大多数物质

are just two or three degrees of separation

同池塘中的淤泥

也不过是两三个食物链级的分别。

from things like pond scum.

All species in an ecosystem,

生态系统内的所有物种，

from the creatures in a coral reef

从珊瑚礁里的生物

to the fish in a lake

到湖里的鱼，

to the lions on the savannah,

再到大草原的狮子，

are directly or indirectly

都直接或间接地

nourished by dead stuff.

由死去的东西喂养。

Most of the organic matter in our bodies,

我们身体内大多数有机物质，

if we trace it back far enough,

如果我们追根究底，

comes from CO2 and water

都来自由光合作用产生的

through photosynthesis.

二氧化碳和水。

Plants use the energy from sunlight

植物用来自光照的能量

to transform carbon dioxide and water from the environment

将环境中的二氧化碳和水

into glucose and oxygen.

转化为葡萄糖和氧气。

That glucose is then transformed

葡萄糖又转换为

into more complex organic molecules

结构更加复杂的有机分子，

to form leaves, stems, roots, fruit, and so on.

成为叶、茎、根、果实等形成的基础。

The energy stored in these organic molecules

这些储存在有机分子中的能量

supports the food chains with which we're familiar.

维持着我们所熟悉的食物链的运转。

You've probably seen illustrations like this

你或许见过与此相似的图表，

or this.

或者这个。

These green food chains

这些绿色食物链

start with living plants at their base.

以活体植物作为它们的基础。

But in real-life terrestrial ecosystems,

但在现实的陆地生态系统中，

less than 10% of plant matter

不到10%的植物体

is eaten while it's still alive.

在它们依然活着的时候被吃掉。

What about the other 90?

那么剩下的90%去哪了呢？

Well, just look at the ground

好吧，那我们就在某个秋天

on an autumn day.

低头看看地上。

Living plants shed dead body parts:

活着的植物枯萎死去的部分会掉落：

fallen leaves, broken branches,

败叶、枯枝，

and even underground roots.

甚至是地下的根茎。

Many plants are lucky enough

很多植物足够幸运能够度过

to go their whole lives without being eaten,

整个生命周期而不被吃掉，

eventually dying and leaving remains.

最终死去，尸体保留了下来。

All of these uneaten, undigested, and dead plant parts,

那所有那些没有被吃掉，被消化 并且已经死去的植物部分，

that 90% of terrestrial plant matter?

我们前面所提到的90%的陆地植物呢？

That becomes detritus,

它们变成了腐质，

the base of what we call the brown food chain,

是我们称之为“棕色食物链” （腐食食物链）的基础，

which looks more like this.

看起来更像这个。

What happens to plants

发生在植物上的一切，

also happens to all other organisms up the food chain:

也同样发生在食物链上端的 其他所有生物身上：

some are eaten alive,

有些在活着的时候就被吃了，

but most are eaten only

但大多数

when they're dead and rotting.

在死掉腐烂之后才被吃掉。

And all along this food chain,

并且沿着整个食物链，

living things shed organic matter

有机物质会从活体上脱落，

and expel digestive waste

活体在死之前排出可分解的废弃物

before dying and leaving their remains to decay.

并留下它们的遗体，直至腐烂。

All that death sounds grim, right?

所有这些死亡听起来很残酷，是吧？

But it's not.

但事实并非如此。

All detritus is ultimately consumed

所有腐质最终会

by microbes and other scavengers,

被微生物及其他食腐动物吃光，

so it actually forms the base of the brown food chain

所以说，腐质事实上是 形成“棕色食物链”的基础，

that supports many other organisms,

支撑了许多其他生物的生存，

including us.

包括我们。

Scientists are learning

科学研究发现，

that this detritus

出人意料的是，

is an unexpectedly huge energy source,

这些腐质是巨大的能量来源，

fueling most natural ecosystems.

为大多数自然生态系统提供燃料。

But the interactions within an ecosystem

但一个生态系统内的相互作用

are even more complex than that.

要比这个复杂的多。

What a food chain really represents

一条食物链真正代表的

is a single pathway of energy flow.

是一个单独的能量流动的途径。

And within any ecosystem,

并且，在任一生态系统中，

many of these flows

许多像这样的流动途径

are linked together

彼此交错连结，

to form a rich network of interactions,

形成一个强大的相互联系的网络，

or food web,

或称食物网，

with dead matter supporting that network at every step.

死了的东西支撑了这个网络的 每一个环节。

The resulting food web

由于食物网各个环节

is so connected

如此紧密相连，

that almost every species

以至于食物网中几乎每个物种

is no more than two degrees from detritus,

同腐质的联系都不超过两个消费级，

even us humans.

甚至我们人类也包括在内。

You probably don't eat rotting things,

你或许不直接吃腐烂的东西，

poop, or pond scum directly,

如粪便或者塘泥，

but your food sources probably do.

但你所吃的食物或许是以这些为生。

Many animals we eat

很多我们所吃的动物，

either feed directly on detritus themselves,

要么是直接由腐质喂养的，

like pork, poultry, mushrooms, shellfish,

比如说猪肉、家禽、蘑菇、贝类，

or catfish and other bottom feeders,

或者鲶鱼及其他底层动物；

要么就是以动物的副产品为生。

or they are fed animal by-products.

So, if you're thinking nature is full of waste,

所以说， 如果你认为大自然充满了废物，

you're right.

你算是说对了。

But one organism's garbage is another's gold,

但你认为是垃圾的东西 别人可能认为是金子，

and all that rotting dead stuff

并且所有这些腐烂的死了的东西，

ultimately provides the energy that nourishes us

随着在食物网中的层层传递，

and most of life on Earth,

最终提供了喂养我们及地球上

as it passes through the food web.

大多数生命所需的能量。

Now that's some food for thought.

这的确是让人回味无穷的事实。