地平线系列：失落的部族（2016）

arrives before 40,000 years ago, in Europe.
所以二者的时间有了重叠
So there is an overlap
可能两个族群相遇时
and potentially when these groups came together,
我们现代人从尼安德特人那里
we did pick up some things from Neanderthals
获得了对我们有利的东西
that were an advantage to us,
从而在欧亚地区更严寒的环境中生活生存
about living and surviving in those colder environments in Europe and Asia.
考古证据暗示了尼安德特人与现代人之间
So the archaeological evidence hints at an exchange of ideas
可能存在思想交流
between Neanderthals and modern humans.
但八年前
But eight years ago,
西伯利亚南部的一座洞穴里的化石碎片
a fossil fragment from a cave in southern Siberia
在古人类学世界
was about to drop what can only be described as a bombshell
引起了轩然大♥波♥
into the world of paleoanthropology.
因为它指出了尼安德特人和现代人
Because it suggested that Neanderthals and modern humans
还有其他邻居
had neighbours.
另一个人类部落就住在他们家门口
Another tribe of humans living right on their doorstep.
阿尔泰山脉深处
Deep in the Altai Mountains,
当今哈萨克斯坦与蒙古接壤处附近
near to where Kazakhstan will one day meet Mongolia,
凛冬将至
winter is coming.
但这个山地部落却在此环境中应对自如
But this mountain-dwelling tribe is at home in their environment.
他们的洞穴位于动物迁徙路线上
Their cave is on a migration route
这条路线大大降低了翻山越岭
which offers herds easy passage through the mountains
去到南方遥远温暖大草原的难度
to the warmer grasslands further south.
出人意料 最终发现这个部落的人
Surprisingly, the eventual discovery of this tribe
竟身处五千六百公里外的德国莱比锡城
would actually be made 3,500 miles away, in Leipzig, Germany.
斯万特·帕珀是马克斯-普朗克研究所的遗传学家
Svante Paabo is a geneticist from the Max Planck Institute
他专攻古DNA研究
and he specialises in archaic DNA.
他的团队正和俄♥罗♥斯♥考古学家合作
He and his team are collaborating with Russian archaeologists
他们正在挖掘深山洞穴
who are excavating the remote mountain cave.
在2008年
So, in 2008,
我们的同事发现了大量不同的骨头
our colleagues found a lot of different bones.
在这些骨头中
And among those bones,
他们发现了这么一小片
they found a tiny little piece,
一小片小指末端指骨的碎片
a little fragment of the last phalanx of a little finger.
只有一小片
Just a piece of it.
斯万特·帕珀教授
马克斯-普朗克进化人类学研究所
肯定是个小孩的 因为它非常非常小
It was obviously from a child, because it was very, very small.
还不太清楚确切的年代
And it's a bit unclear how old it is.
至少有五万年左右了 很有可能更早
It's at least in the order of 50,000 years, probably older.
他们把它和其他骨头一起
And they sent this, along with some other bones,
寄到了我们在莱比锡城的研究所
to us in Leipzig.
马克斯-普朗克进化人类学研究所
他们把它寄给斯万特
They sent it to Svante
希望他们团队能提取部分DNA
in the hope that he and his team could extract some DNA
看看能否鉴定这块人骨
and perhaps determine whether the bone
是尼安德特人的还是智人[现代人]的
was Neanderthal or Homo sapiens.
我们给这块骨头取样过程中要做的是
What we do when we get the bone to sample
给表面开个小口
is to remove the surface and little area,
用牙钻钻一个孔
drill the hole with a dentistry drill,
采集飞出的粉末
so we get powder out.
我们要从粉末中离析出DNA
From that, we then isolate the DNA.
我们对它进行提纯
We purify it away
除去骨骼中的其他成分
from all of the other components of the bones
包括矿物质 蛋白质 脂肪
at this end, the minerals are there, the proteins, the fats.
然后你就能把它
And you then have it in a form
放到测序仪里了
that you can feed into sequencing machines.
研究古DNA的困难之处在于
The problem when you study ancient DNA is that first of all,
首先它在残骸中所占比例很低
there's very little there, in the remains.
大部分的DNA并不是这块骨头上的
The vast majority of the DNA is not indigenous to the bone,
而是它腐烂在洞穴之后的数万年里
but comes from bacteria and fungi that have colonised the bone
细菌真菌带给它的
over tens of thousands of years when it was deposited in the cave.
也许最困难的一点在于
And perhaps the biggest problem is
它存在被现在人DNA污染的风险
the risk of contamination from present-day human DNA,
实验室里的人
from ourselves in the laboratory,
或者是像这样有人走动的房♥间里
in a room like this, where people move around.
空气中的灰尘有一大部分其实是皮肤碎屑
A large part of the dust in the air is actually skin fragments
而一粒这样的灰尘中含有的DNA
and a single such dust particle can contain a lot more DNA
比骨头样本中要多得多
than we have in our sample of the bone.
DNA是非常脆弱的 不易保存
DNA is very fragile and it doesn't preserve easily.
这块骨头在洞穴内历经了数千年的岁月
But amazingly, despite lying for thousands of years in a cave,
令人惊讶的是其中的DNA却几乎完好无损
the DNA in that tiny bone had hardly degraded at all.
小指的这一小部分保存得非常完好
This little part of the little finger was so well-preserved,
我们能够测定出
we were able to sequence,
就像现在测定出的
actually, the entire genome to a very high quality,
你我的高质量基因序列
as high a quality as you would sequence your or my genome today.
能够从5万年前的骨头中
It's an astonishing achievement
获得一组完整的基因序列是让人震惊的成就
to get a complete genome from a 50,000-year-old bone.
但在鉴定他们属于哪种人种的时候
But the biggest shock came when they tried to identify
最令人震惊的事情发生了
what species of human it was.
我们惊讶地发现那并不是尼安德特人
We were very surprised to find that it was not a Neanderthal.
和我们见过的尼安德特人的基因
It was very, very distant from other Neanderthal genomes
有很大的不同
we had looked at.
我们立马意识到这是非常奇特的东西
So we immediately realised this was something very special.
既不是尼安德特人也不是现代人
It was not a Neanderthal, it was not a modern human,
而是新的人种
it was something new.
我们发现了一个已经灭绝了的人种
We had found a new form of extinct human.
完全出人意料
This was completely unexpected.
一个和我们有亲缘关系
A human that was related to all of us,
基因却和我们不同的人种
but genetically distinct.
他们是我们的另一组表亲
Another group of cousins.
我们自己内部讨论了很久
So we had a lot of discussions among ourselves
和俄♥罗♥斯♥的同事也讨论了很久
and our Russian colleagues
该如何称呼这类人种
what we'd call this group of humans.
在经过一系列讨论后
And after a lot of back and forth,
我们决定称他们为丹尼索瓦人
we agreed to call them the Denisovans.
就像尼安德特人是
Just like Neanderthals are called Neanderthals
以其第一次发现的地点
after the Neander Valley,
尼安德谷命名的一样
where the first remains of Neanderthals were found,
丹尼索瓦人也以
Denisovans are called
他们首次被发现的地点命名
after the first place where they were found.
令人沮丧的是对于丹尼索瓦人我们知道的很少
We know very little of Denisovans, it's very frustrating.
我们知道他们和尼安德特人交替
We do know that they lived in this cave and that they lived intermittently
住在这个山洞
with Neanderthals there.
看起来尼安德特人是先住进去的
There seem to have been Neanderthals there early,
然后是丹尼索瓦人
there were then later Denisovans
之后又是尼安德特人
and later again, Neanderthals.
对我来说 这是地球上一处令人惊奇的地方
And it's, to me, a really amazing place in the world,
因为这是我们唯一知道的
because it's the only place we know
至少有三个人类种群居住过的地方
that at least three different forms of humans have lived.
我们能够确定
We can tell that
相比我们 丹尼索瓦人与尼安德特人更相近
Denisovans were more closely related to Neanderthals than to us.
60万年前 尼安德特人的祖先
Whereas the ancestors of Neanderthals and modern humans
和现代人的祖先分离
split around 600,000 years ago,
而丹尼索瓦人是40万年前
Denisovans split from a common ancestor with Neanderthals,
从尼安德特人中分离出去的
about 400,000 years ago.
说真的 我们只能从基因中了解他们
And really, we only know about this species from their genetics.
我们根本不了解他们的身体构造
We don't know much about their anatomy at all,
而化石记录残缺不全
the fossil record is so fragmentary.
对山洞进一步挖掘后
Further excavations in the cave
我们发现了两枚丹尼索瓦人的牙齿
have uncovered two Denisovan teeth
而这是目前我们对于新发现的
and so far, that is all the physical evidence
已经灭绝的山居人种仅有的物证
we have of this new lost tribe of mountain-dwelling humans.
目前亟待解决的问题是
The burning question that remains, though,
丹尼索瓦人遇到过我们四处漫游的祖先吗
is did Denisovans ever meet our own wandering ancestors?
关于智人最早起源于非洲
It is well accepted that our species, Homo sapiens,
已经是如今被广泛接受的事实
originated in Africa.
但是我们的祖先何时
But just how and when our ancestors
以何种方式离开非洲去征服世界
left Africa to colonise the globe
才是被广泛讨论的问题
has been a matter of considerable debate.
每一组基因以及化石的新发现
And each new piece of genetic and fossil evidence
都在改变着我们的看法
changes our understanding.
一些近期的发现
Some very recent finds