生命的奇迹（2013）

在六千五百万年间
And over 65 million years, they have blossomed
它们繁衍出无数后代
into hundreds and thousands of individuals,
并成为马达加斯加最具标志性的动物
and become Madagascar's most iconic animals.
米钦祖自然保护区
马达加斯加东部
寻找这些古老远洋者的后代并非易事
Finding the descendants of those ancient mariners is not easy.
但当地的向导约瑟夫已经追踪它们多年
But local guide Joseph has been tracking them for years.
他会帮我找到它们
And he's going to help me find them.
大狐猴
大狐猴属
树顶上的是一只大狐猴
There at the top of the tree is an indri,
这是马达加斯加岛上最大的一种狐猴
which is the largest lemur in Madagascar.
此刻它正坐在那儿安静地看着我们
He's just sat there watching us quietly at the moment.
这是一只很特别的狐猴
This lemur here is a very special lemur.
它有一个名字 叫大卫
He has a name, he's called David.
是以爱丁堡罗夫爵士的名字命名的
After Sir David Attenborough.
我们现在能如此接近它
Now, we can only do this because
是因为约瑟夫已经和这些狐猴相处很久了
Joseph has spent a lot of time with these lemurs.
所以它们信任他
So they trust him.
因此貌似也信任我
And therefore, it seems, they trust me.
它的手真大
Its enormous hands!
人们认为仅能在
The reason, it's thought,
马达加斯加找到狐猴
that we find lemurs here in Madagascar and Madagascar alone
是因为这里没有类人猿
is because there are no simians,
没有黑猩猩
there are no chimpanzees,
没有任何人类的近亲
none of my ancestral family,
在过去的数千万年里与它们竞争
dating back tens of millions of years, to out-compete them.
跟据人们的推测
So what's thought to have happened
六千五百万年前
is that around 65 million years ago
这些狐猴的祖先
one of the lemur's ancestors
穿越莫桑比克海峡 来到这里
managed to sail across the Mozambique Channel, and landed here.
这里没有任何竞争者
There were none of those competitors here,
所以狐猴开始繁荣兴旺起来
and so the lemurs have flourished ever since.
马达加斯加岛上现有超过九十种或亚种
There are now over 90 species of lemur, or subspecies,
的狐猴
in Madagascar,
却没有一种类人猿
and no species of my lineage, the simians.
在漫长的时间里 狐猴不断演变
Over a vast sweep of time, the lemurs have diversified
以便适应不同的栖息地
to fill all manner of different habitats.
从南边的干旱荆棘丛
From the arid, spiny forests of the south...
到北边的岩石谷
To the rocky canyons in the north,
这个岛的某些因素
there is something about this island
促使狐猴的DNA产生
that is allowing the lemur's DNA to change
最神奇的转变
in the most amazing ways.
我们正在寻找一只指猴
We're on the hunt for an aye-aye,
这是所有现存狐猴中跟它们的祖先
the most closely related of all the surviving lemurs
最接近的一种
to their common ancestor.
在那儿 看那根藤在动
Right there, see the vine moving！
对
Oh, yes...
就是它
Oh, yeah.
打开灯之后 我们看到了
Just shone the light up, and we saw these absolutely...
一对红色的明眸 闪闪发亮
Two bright red eyes, shining out.
它正在非常高的地方
She's very high up at the moment.
不想在森林里把它跟丢了
Don't want to lose sight of her in this forest,
这里又黑 树木又茂盛
which is very dark and dense.
这个团队发现了一只雌性指猴和它的儿子
The team have located a female aye-aye, and her son.
他们想安装无线电项圈来追踪它们的行动
They want to attach radio collars to track their movements,
以便更好地了解它们在森林中的活动范围
and better understand how far they range through these forests.
但首先他们得用麻醉镖让它们安静下来
But first, they must sedate them with a dart.
他在等它爬到足够低的地方
He's waiting for it to come down low enough
然后给它利落的一击
to get that clean shot,
显然在现在这种情况下
I mean, how you get a clean shot
想要一击即中是不可能的
in this I have no idea.
在茂密的森林中游荡了两个小时之后
After two hours of traipsing through the treacherous forest,
那只指猴依然自♥由♥自在
the aye-ayes remain at large.
这就是昨晚被麻醉的那只指猴
Well, here is the aye-aye that was tranquillised last night.
指猴
指猴属马达加斯加亚种
在我们离开半小时后终于抓到它了
They finally got her about half an hour after we left.
我想大概是我们的存在惊扰了它
I think it was probably because we were disturbing her.
显然我们一离开它就从树上下来了
Apparently as soon as we'd gone, she came down the tree
然后就被注射了镇定剂
and she was tranquillised.
现在你可以看到它非常安静
And as you can see she's pretty well sedated now,
这对我来说很不错
which is fortunate for me
我可不想让它对我使用
because she has certain adaptations
它为了适应环境而进化出的某些能力
that I wouldn't like to be deployed.
来看看它的牙齿
You can see there her teeth.
它的牙齿对灵长类动物来说非同一般
Her teeth are very unusual for a primate,
可以说独一无二 因为它们一直在生长
in fact, unique, because they carry on growing,
所以从这方面来讲它更像啮齿动物
so she's much more like a rodent in that respect.
靠这些牙齿它能啃进木头
And that's so she can gnaw into wood.
指猴在马达加斯加占据着独特的生态位
You see, aye-ayes have filled a unique niche on Madagascar.
在世界上的其他地方
It's a niche that's filled by woodpeckers
占据这一生态位的通常是啄木鸟
in many other areas of the world.
它以树木中的蛴螬和虫子为食
What she does is she feeds on grubs and bugs inside trees,
为此它拥有一些独特的适应性能力
and to do that, she has several unique adaptations
牙齿就是其中之一
of which her teeth are one.
最令人吃惊的是它的中指
The most startling is this central finger here.
非常古怪
It's bizarre.
它有一个球窝关节
It's got a ball and socket joint, for a start,
所以可以360度旋转
so it has complete 360-degree movement.
感觉就像是折断了一样 其实不是
It feels to me almost as if it's broken, but it isn't,
你可以把它往任意方向转动
it's just, you can move it around in any direction.
首先它会用这跟手指
And she uses that finger initially
在树干上敲一敲
to tap on the trunk of the tree,
然后用这双大耳朵去听
and then, listening to the echo from that tapping,
敲击产生的回音
with these huge ears
它能探测到虫子在哪里
she can detect where the grubs are.
接着 它用像啮齿类动物一样的牙齿
And then, she gnaws through the wood
把木头咬开
with those rodent-like teeth,
再把这根手指伸进洞里
and then uses this finger again to reach inside the hole
把虫子捉出来
and get the bugs out.
问题是为什么会这样
So the question is, why?
一种动物是如何做到精准地适应
How could an animal be so precisely adapted
特定的生活方式的呢
to a particular lifestyle?
现在它要醒过来了
She's waking up now!
答案是自然选择
And the answer is natural selection.
变化的起源要追溯到很久以前
See, what must have happened is way back,
狐猴的祖先 也就是狐猴型下目
when the ancestors of the lemurs - the Lemuriformes -
最初到达马达加斯加的时候
arrived in Madagascar,
必定发生了突变
there must have been a mutation
使得其中一只狐猴的中指
that lengthened the middle finger
稍微加长了一些
ever so slightly of one of those lemurs.
这一变化一定给它带来了好处
And that must have given it an advantage.
或许让它得以
That must have allowed it
伸进小洞 寻找蛆虫
perhaps to reach into little holes and search for grubs.
加长的中指一定有它的用途
There's some reason why that lengthened middle finger
所以那个基因
meant that that gene was more likely to be passed
才更有可能被一代
to the next generation
又一代传承下去
and then down to the next generation.
因此无数种的可能性被缩小了
So that landscape of possibilities is narrowed,
因为那个基因一定存在
it's narrowed because that gene persists.
并且至少存在了四千万年
And it's persisted now for at least 40 million years,
因为这一物种已经
because this species has been on
在这条生命之树的分支上
one branch of the tree of life now
存在了四千余万年
for over 40 million years.
年复一年
And so, over those years that middle finger
中指变得越来越特化
has got more and more specialised.
自然选择使得指猴
Natural selection has allowed
奇妙突变的手指
the aye-aye's wonderfully mutated finger
蔓延至整个种群
to spread through the population.
这条法则对所有生物都适用
And this same law applies to all life.
要是你发生的突变可以帮助你生存
If you have a mutation that helps you in the struggle to survive,
你就很可能留下更多的子嗣
you are more likely to leave more offspring.