生命的奇迹（2013）

在下一代中
And in the next generation,
这种突变更可能延续下去
that mutation is more likely to survive.
这只动物是个绝妙的例子
So this animal is a beautiful example,
或许是世上最棒的例子
probably one of the best in the world,
说明了自然选择的筛选是如何让动物
of how the sieve of natural selection produces animals
完美地适应它们的生存环境
that are perfectly adapted to live in their environment.
研究指猴的原因有很多
Now, there are many reasons to study the aye-aye.
下面就是个好理由
But here's a good one.
二十世纪七十年代 人们以为指猴灭绝了
In the 1970s, it was thought the aye-aye was extinct.
现在我们知道
Now, we know there are
在马达加斯加的森林里还有数千只
several thousand in the forests of Madagascar -
五千 六千或是七千 肯定少于一万只
5,000, 6,000, 7,000, certainly less than 10,000 -
但是在过去的五十年里
but over the last 50 years,
超过50%的森林消失了
50% of this forest has vanished.
这种动物拥有
This is an animal that's been around as a species
四千万年的历史
for over 40 million years.
了解它们是如何生存繁衍 如何在栖息地
So it's important to know how these animals are doing,
不断变小时幸存下来 很是重要
and how they're surviving in this diminishing habitat.
自然选择能够解释指猴的进化
Whilst natural selection explains why the aye-aye evolved,
但光凭它无法解释一小群个体是如何
it alone can't explain how a small group of individuals,
历经六千万年历史
over 60 million years ago,
孕育出现今逾90种不同的狐猴
gave rise to over 90 different species of lemur today.
不过另一种生命形态可以给我们提供线索
But there is another form of life that can offer us a clue.
身处在这乔林林冠
Up here in the high forest canopy,
又是与之前的森林地面
we're in a very different environment
完全不同的环境
to the one down there on the forest floor.
这里更为干燥 几乎如同沙漠
It's a more arid environment, it's almost like a desert.
直接暴露在阳光下 使得水更为稀少
It's exposed to the sun, water is harder to come by.
所以 这里有茫茫无涯的生态位
And so, this is a sea of different niches,
被另一群动物占据利用
that are able to be occupied and exploited by animals
这群动物
that are different to the ones
与地面上的动物截然不同
you'll find down there on the floor.
我们能够真切地感觉到 这仿佛是座岛屿
So, in a very real sense, this is an island,
供殖民居住的岛屿
an island to be colonised.
果然 甚至是这里也有居住者
And sure enough, there are settlers to be found, even here.
看那个
You see that thing
好像是树枝上悬挂的泥球
that looks like a muddy ball there, on the branch?
那里是蚁穴
Well, that's an ants' nest,
是举腹蚁的家
it's home to a species of crematogaster ants
蚂蚁
举腹蚁属
不仅仅是马达加斯加独有的生物
that are unique not only to Madagascar,
而且是整个林冠中独一无二的
but to the forest canopy.
瞧 这些蚂蚁之所以特别
You see, what makes those ants unique
就是因为它们能够搭建自己的巢穴
is that they can build their own nests.
很少有蚂蚁可以做到这一点
There are very few species of ants that can do that.
那是一座岛屿 一个生态位
So that is an island, that is a niche,
使这种蚂蚁得以繁衍
and it's allowed that species of ant to develop
因为这里完全与其他生态环境相隔绝
because they're isolated from the rest of the ecosystem.
很令人惊讶 在这个微生态中
And astonishingly, within this niche,
发现了另一种对科学来说全新的生命形态
another form of life new to science has been discovered...
一种未受蚂蚁伤害 存活于此的甲虫
A beetle that manages to survive here unharmed by the ants.
它是怎么做到的 至今是个谜
How it does it is a mystery.
但是我们知道人们只在这些巢穴内部
But what IS known is that this particular species
发现过这种特别的物种
has only ever been found inside these nests.
所以这里真的是一个迷你生态系统
So, that really is its own mini-ecosystem,
生活在这座岛上的物种独一无二
with species living in it that are unique to that island.
我们生活在不断变化的动态世界
We live on an ever-shifting, dynamic world
使得大量岛屿被创造
that creates islands in abundance.
地球上的山脉 河谷 峡谷
Earth's mountain ranges, river valleys and canyons
创造出孕育生命的岛屿
all create islands for life.
那些狐猴的祖先
And it's these islands
到达马达加斯加时发现的
that those ancestors of the lemurs found
正是这些岛屿
when they arrived in Madagascar.
种群就在这空无一物的生态位里被隔离
Empty niches, where populations became isolated,
历经漫漫的时间长流
and over great swathes of time
演变成如此丰富多彩的形态
involved into such wonderfully diverse forms.
《物种起源》诞生的150年后
150 years on from the Origin Of Species,
达尔文精妙优美的洞察
the subtlety and beauty of Darwin's insight
依旧呈现在我们眼前
is still revealing itself to us.
它描述了我们美妙复杂的生命之树
It describes how our beautiful, complex tree of life
是如何从荒凉的宇宙中生长起来的
has grown from a once desolate universe.
碳的化学性质
The chemistry of carbon
使得能够自我复♥制♥的分子
allows for the existence of a molecule
得以存在
that is able to replicate itself,
信息得以一代一代传下去
and pass information on from generation to generation.
分子结构可能存在随机变化
There can be random changes in the structure of that molecule -
也就是变异 变异会经历环境
mutations - and they are tested by their interaction
和生物的交互考验
with the environment and with living things.
通过考验者能够幸存下来
The ones that pass that test survive,
而没能通过的则被淘汰
and the ones that fail that test are lost.
岛屿上的生物互相分离隔绝
The separation and isolation of living things onto islands -
岛屿可能是物理上的 比如马达加斯加
which may be physical, like Madagascar,
也可能只是一棵树上的一根枝桠
or just the single branch of a single tree -
隔离导致了物种形成 高度适应
results in speciation, the explosion of living forms
各自生态位的生物激增
highly specialised to occupy niches within niches.
这就是地球上生命多样性的解释
And this is the explanation for the diversity of life on Earth.
达尔文写道 "这种生命观是极其壮丽的"
"There is grandeur in this view of life," As Darwin wrote,
理解这一切是如何发生只会加剧这种惊奇
and understanding how it happened surely only adds to the wonder.
如同爱因斯坦的相对论一样的精准
As precise as Einstein's theories of relativity,
如同热力学一样的深奥
and as profound as thermodynamics,
达尔文告知了我们又一条普遍规律
Darwin has given us another universal law.
通过自然选择的进化
Evolution by natural selection.
如果进化是这座岛屿的法则
And if evolution is the law on this island,
那它也会适用于整个宇宙
then it will apply throughout the cosmos.
这引出了一个大问题
Which begs a big question.
在茫茫繁星之中
Could there be other
有没有其它 "美丽的生命之树"
"Trees of life most beautiful" amongst the stars?
2011年 我们发现了一颗围绕
In 2011, we discovered a rocky planet
远处一恒星做轨道运动的岩态行星
orbiting around a distant star,
它的白昼温度
with daytime temperatures
和地球上的差别并不大
not too dissimilar to those found on Earth.
宇宙中就算没有数以十亿计
Now, there must be millions
也会有数百万这样的星球
if not billions of such planets out there in the universe,
我无法相信没有一个星球
and it's inconceivable to me that none of them
拥有和我们一样
will have trees of life
甚至更复杂的生命之树
as complex or even more complex than our own.
但这并没有使我们的树贬值
But that doesn't devalue the existence of OUR tree,
因为它是独一无二的
because our tree is unique.
它由成千上万的分支构成
It consists of thousands of branches,
分支之间互相依赖
all interdependent on thousands of others,
而精确的结构又依赖于随机事件
and the precise structure depends on chance events,
比如狐猴六千五百万前的
like the passage of the lemurs
远渡重洋
across the ocean 65 million years ago.
所以当你明天外出
So when you go outside tomorrow,
看看身边的世界
just take a look at a little piece of your world.
花♥园♥的一角 或是公园
A corner of your garden, or a park,
甚至是从人行道的缝隙中生长出来的小草
or even the grass that's growing in a crack in the pavement.
因为那里会有生命 独一无二的生命
Because there will be life there, and it will be unique.
宇宙中再也没有第二个地方会与它完全一样
There will be nowhere like that anywhere else in the universe.
这使得我们的树
And that makes our tree,
从最健壮的枝干到最脆弱的枝桠
from the sturdiest branch to the most fragile twig,
都是难以形容的珍贵
indescribably valuable.
繁星之下 你我相遇
Underneath the stars you met me
繁星之下 你我别离
And underneath the stars you left me
繁星是否 为我惋惜
I wonder if the stars regret me
如若初见 定会爱怜
I'm sure they'd like me if they only met me
来去自如 随心自♥由♥
They come and go of their own free will
悄然离开
Go gently...