Jambo, bonjour, zdravstvujtye, dayo: these are a few of the languages that I've spoken little bits of over the course of the last six weeks, as I've been to 17 countries I think I'm up to, on this crazy tour I've been doing, checking out various aspects of the project that we're doing. And I'm going to tell you a little bit about later on. And visiting some pretty incredible places, places like Mongolia, Cambodia, New Guinea, South Africa, Tanzania twice -- I was here a month ago.
(你好) 這幾種語言 我在過去六周裡或多或少有機會用到 我正在進行一個瘋狂的旅程,總共需要跑遍17國 去檢視我們正在進行的一項研究計畫的各方面進度 我之後會向各位介紹這個計畫的內容 因為這個計劃,我拜訪許多絕妙的地方 像是蒙古、柬埔寨、新幾內亞、南非,還來了坦尚尼亞兩次 而且上個月才剛來過
And the opportunity to make a whirlwind tour of the world like that is utterly amazing, for lots of reasons. You see some incredible stuff. And you get to make these spot comparisons between people all around the globe. And the thing that you really take away from that, the kind of surface thing that you take away from it, is not that we're all one, although I'm going to tell you about that, but rather how different we are. There is so much diversity around the globe. 6,000 different languages spoken by six and a half billion people, all different colors, shapes, sizes. You walk down the street in any big city, you travel like that, and you are amazed at the diversity in the human species.
能有機會經驗這種旋風式的環遊世界之旅 是件無與倫比的事,原因很多 首先是可以大開眼界 同時還能在全球各地 比較各式各樣的人種 最重要的是,你能夠領悟到 一件深刻的事實 那並非「全球人類本一家」,雖然之後我會討論這個議題 而是相反的—我們彼此之間有多麼不一樣 放眼全球人種的高度多樣性 六十五億人口,不同膚色、容貌及體型 並講著六千多種語言 當你經驗類似旅行,漫步在各國大城市的街頭時 全球人種的高度多樣性絕對會令你讚嘆
How do we explain that diversity? Well, that's what I'm going to talk about today, is how we're using the tools of genetics, population genetics in particular, to tell us how we generated this diversity, and how long it took. Now, the problem of human diversity, like all big scientific questions -- how do you explain something like that -- can be broken down into sub-questions. And you can ferret away at those little sub-questions.
我們該如何去解釋這樣的多樣性? 這正是我今天的主題 我將解釋我們如何運用遺傳學的研究方法 特別是族群遺傳學,解釋人種多樣性的來源 以及經過多少時間才產生 現在,有關人種多樣性的問題 像其他所有重要的科學問題一樣 無法三言兩語就解釋完 所以我將這個問題分成幾個子項目, 再去逐一解釋
First one is really a question of origins. Do we all share a common origin, in fact? And given that we do -- and that's the assumption everybody, I think, in this room would make -- when was that? When did we originate as a species? How long have we been divergent from each other?
首先是人類的起源 我們是不是全都來自於同一個祖先呢? 假設我們贊同這個觀點 在場的每一位應該會想問:「那是從什麼時候開始?」 我們是在什麼時間點,形成同一個物種? 之後又經過多久,才分化成現在的高多樣性
And the second question is related, but slightly different. If we do spring from a common source, how did we come to occupy every corner of the globe, and in the process generate all of this diversity, the different ways of life, the different appearances, the different languages around the world?
第二個問題與之前相關,但有些不同 如果人類的確有共同祖先 我們又是如何散布到世界上每個角落? 並且一步步發展成不同人種 不同的社會型態、不同的外表 及不同語言的呢?
Well, the question of origins, as with so many other questions in biology, seems to have been answered by Darwin over a century ago. In "The Descent of Man," he wrote, "In each great region of the world, the living mammals are closely related to the extinct species of the same region. It's therefore probable that Africa was formerly inhabited by extinct apes closely allied to the gorilla and chimpanzee, and as these two species are now man's nearest allies, it's somewhat more probable that our early progenitors lived on the African continent than elsewhere."
人類起源的問題,如同其他生物學問題 看起來似乎在超過一百年以前,已經被達爾文解開了 他在著作「人類的起源」中寫道: 在世界每個區域,現存的哺乳動物 都與當地已絕種的物種有緊密的關係 所以已絕跡的類人猿,之前可能住在非洲 他們與大猩猩與黑猩猩應是近親 這兩個物種是最接近我們現代人類的「親戚」 因此,人類最原始的祖先 有可能來自非洲大陸,而非其他地區
So we're done, we can go home -- finished the origin question. Well, not quite. Because Darwin was talking about our distant ancestry, our common ancestry with apes. And it is quite clear that apes originated on the African continent. Around 23 million years ago, they appear in the fossil record. Africa was actually disconnected from the other landmasses at that time, due to the vagaries of plate tectonics, floating around the Indian Ocean. Bumped into Eurasia around 16 million years ago, and then we had the first African exodus, as we call it. The apes that left at that time ended up in Southeast Asia, became the gibbons and the orangutans. And the ones that stayed on in Africa evolved into the gorillas, the chimpanzees and us. So, yes, if you're talking about our common ancestry with apes, it's very clear, by looking at the fossil record, we started off here.
這樣就解決人類源起的問題啦! 我們可以解散了,不是嗎? 等等,還沒結束!達爾文解釋的是人類的遠祖 我們與類人猿共同的祖先 很明顯的,類人猿起源於非洲大陸 從化石推斷,大約是從兩千三百萬年前開始出現 當時,非洲大陸已經與其它大陸隔絕 由於板塊持續運動,非洲大陸在印度洋上漂浮 並在一千六百萬年前與歐亞板塊碰撞 因此產生了所謂的第一次「非洲物種遷移」 遷徙的類人猿最後在東南亞落腳 演化為長臂猿和猩猩 那些留在非洲的 演化為大猩猩、黑猩猩,還有我們人類 所以沒錯,如果指的是人類與猿類的共同祖先 化石紀錄的確證明我們起源於非洲大陸
But that's not really the question I'm asking. I'm asking about our human ancestry, things that we would recognize as being like us if they were sitting here in the room. If they were peering over your shoulder, you wouldn't leap back, like that. What about our human ancestry? Because if we go far enough back, we share a common ancestry with every living thing on Earth. DNA ties us all together, so we share ancestry with barracuda and bacteria and mushrooms, if you go far enough back -- over a billion years. What we're asking about though is human ancestry. How do we study that?
但這不是我真正的問題 我問的是「人類」本身的祖先 就是那些會被認為長得像我們的東西 就像假設他們就坐在這個空間裡 假如他們正從你的背後看著你 你也不會嚇一大跳。那麼,人類的祖先從哪裡來? 如果我們回溯到遠古時期 我們與地球上所有的生物都擁有共同祖先 依據DNA排列,我們甚至跟梭魚、 細菌、蘑菇的祖先都一樣—如果回溯到數十億年前 但是我問的是人類本身的祖先 怎麼研究這個問題呢?
Well, historically, it has been studied using the science of paleoanthropology. Digging things up out of the ground, and largely on the basis of morphology -- the way things are shaped, often skull shape -- saying, "This looks a little bit more like us than that, so this must be my ancestor. This must be who I'm directly descended from."
遠古人類學家其實已經研究這個問題很多年了 挖掘古生物遺跡 大致上依據型態去分類 按照各種骨頭的形狀去分類—多數是頭骨 舉例來說,這個比那個看起來更像我們一點 所以想必這個就是我們的祖先
The field of paleoanthropology, I'll argue, gives us lots of fascinating possibilities about our ancestry, but it doesn't give us the probabilities that we really want as scientists. What do I mean by that? You're looking at a great example here. These are three extinct species of hominids, potential human ancestors. All dug up just west of here in Olduvai Gorge, by the Leakey family. And they're all dating to roughly the same time. From left to right, we've got Homo erectus, Homo habilis, and Australopithecus -- now called Paranthropus boisei, the robust australopithecine. Three extinct species, same place, same time. That means that not all three could be my direct ancestor. Which one of these guys am I actually related to? Possibilities about our ancestry, but not the probabilities that we're really looking for.
我必須說,古生物學在這一點上 提供我們許多有趣的可能答案 但是沒有提供每一項可能答案的機率,這是科學家真正需要的 怎麼說呢? 這邊就有一個很好的例子 這三種絕種的原始人 每一種都可能是人類的祖先 三種都是李奇家族在奧度瓦伊谷以西挖掘出來的 他們生活的時期也都差不多 從左到右分別是直立人 、巧人 以及南方古猿,現在稱為鮑氏傍人的更新紀靈長類 三個絕跡的物種,出現在同一個時間、同一個地點 這意味著不可能三種都是我們的祖先 那我們到底是從哪一種演化來的呢? 這些「可能」是我們的祖先,但沒有告訴我們這個「可能」的機率
Well, a different approach has been to look at morphology in humans using the only data that people really had at hand until quite recently -- again, largely skull shape. The first person to do this systematically was Linnaeus, Carl von Linne, a Swedish botanist, who in the eighteenth century took it upon himself to categorize every living organism on the planet. You think you've got a tough job? And he did a pretty good job. He categorized about 12,000 species in "Systema Naturae." He actually coined the term Homo sapiens -- it means wise man in Latin. But looking around the world at the diversity of humans, he said, "Well, you know, we seem to come in discreet sub-species or categories." And he talked about Africans and Americans and Asians and Europeans, and a blatantly racist category he termed "Monstrosus," which basically included all the people he didn't like, including imaginary folk like elves.
另一個角度,是從體型來判斷 使用人們到目前為止僅有的資料 同樣的,大部分是靠頭骨形狀 第一個將這種方式系統化的科學家是林奈 卡爾·林奈, 瑞典植物學家 在十八世紀,獨自完成這項工作 把地球上所有生物做好分類 還會抱怨你的工作很難嗎? 他做得相當不錯 將一萬兩千個物種分類,記載在「自然系統」一書中 他還創造了智人一詞--在拉丁文中是指有智慧的人 環顧這世上五花八門的人種,他說: 我們只是具有微妙差異的亞種,或不同的智人而已 然後他開始區分出非洲人、美洲人、亞洲人、和歐洲人 也公然地以種族歧視的觀點,區分出一種「怪獸」 基本上囊括所有他不喜歡的人種 還包括妖精等想像人物
It's easy to dismiss this as the perhaps well-intentioned but ultimately benighted musings of an eighteenth century scientist working in the pre-Darwinian era. Except, if you had taken physical anthropology as recently as 20 or 30 years ago, in many cases you would have learned basically that same classification of humanity. Human races that according to physical anthropologists of 30, 40 years ago -- Carlton Coon is the best example -- had been diverging from each other -- this was in the post-Darwinian era -- for over a million years, since the time of Homo erectus. But based on what data? Very little. Very little. Morphology and a lot of guesswork.
我們很容易就可以把他的行為,當成是十八世紀中古科學家 立意良善卻愚昧的「前達爾文」研究 並且嗤之以鼻 但是,如果你曾經修過人類學的課程 在二、三十年前, 這還是正統的人類分類學呢! 根據三、四時年前人類學家的說法-- 卡爾頓 庫恩為此學說的代表性典範-- 人類族群分支,出現在超過百萬年前,直立人的出現以後 --這可是後達爾文時代的學說了 可是這樣的觀點的根據又是什麼? 很少,幾乎沒有。單是靠形態學加上各種猜想而已
Well, what I'm going to talk about today, what I'm going to talk about now is a new approach to this problem. Instead of going out and guessing about our ancestry, digging things up out of the ground, possible ancestors, and saying it on the basis of morphology -- which we still don't completely understand, we don't know the genetic causes underlying this morphological variation --
我今天要講的就是 一個新的方法,來解答這個問題 這個新方法不是挖掘骨骸, 到處碰碰運氣 單憑化石外型,猜想我們的祖先到底是誰 甚至在我們尚未完全了解如何運用化石外型合理推論 因為我們還不確定遺傳與外型的關聯性
what we need to do is turn the problem on its head. Because what we're really asking is a genealogical problem, or a genealogical question. What we're trying to do is construct a family tree for everybody alive today. And as any genealogist will tell you -- anybody have a member of the family, or maybe you have tried to construct a family tree, trace back in time? You start in the present, with relationships you're certain about. You and your siblings, you have a parent in common. You and your cousins share a grandparent in common. You gradually trace further and further back into the past, adding these ever more distant relationships. But eventually, no matter how good you are at digging up the church records, and all that stuff, you hit what the genealogists call a brick wall. A point beyond which you don't know anything else about your ancestors, and you enter this dark and mysterious realm we call history that we have to feel our way through with whispered guidance.
我們必須做的是,把問題倒過來看 畢竟想探討的是個族譜議題 或是尋找人類族譜的答案 因此,我們試圖建立起一個能連結所有人類的族譜 就像每個族譜學者會告訴你的-- 每個人都有家族成員,或者你可能 也曾試著建構自己的族譜,追溯祖先的歷史? 你會從那些你確定的家族關係著手 例如:你和兄弟姊妹有著共同的父母 你和堂表親有著共同的祖父母 漸漸地,你可以回溯到更遙遠的過去 加入更多遠親關係 到最後,無論你多麼擅長挖掘教會檔案 或是其他家族資料,你終會遇到一個狀況—族譜學家口中的「碰壁」 也就是,到了這一步,你再也找不出更多祖先的訊息 然後陷入一個神祕的世界—我們所謂的「歷史」 接著,只能仰賴微小的線索,繼續前進
Who were these people who came before? We have no written record. Well, actually, we do. Written in our DNA, in our genetic code -- we have a historical document that takes us back in time to the very earliest days of our species. And that's what we study.
我們的祖先是誰?他們先來後到的順序呢? 我們沒有文字記錄。嗯,事實上,我們是有... 這些文字寫在我們的DNA上,藏在我們的遺傳密碼之中 像整套的歷史捲軸,帶領我們回到過去 直到人類的起源;這就是我們的研究
Now, a quick primer on DNA. I suspect that not everybody in the audience is a geneticist. It is a very long, linear molecule, a coded version of how to make another copy of you. It's your blueprint. It's composed of four subunits: A, C, G and T, we call them. And it's the sequence of those subunits that defines that blueprint. How long is it? Well, it's billions of these subunits in length. A haploid genome -- we actually have two copies of all of our chromosomes -- a haploid genome is around 3.2 billion nucleotides in length. And the whole thing, if you add it all together, is over six billion nucleotides long. If you take all the DNA out of one cell in your body, and stretch it end to end, it's around two meters long. If you take all the DNA out of every cell in your body, and you stretch it end to end, it would reach from here to the moon and back, thousands of times. It's a lot of information.
先來簡單介紹一下DNA 我猜應該不是每個聽眾都是遺傳學家 DNA是個很長的鏈型分子,一本密碼書 教你如何複製自己,也就是建構你的藍圖 由四種成分組成,我們稱之為A、C、G、T 這些成分的排列順序決定了整個藍圖 DNA有多長?大概有數十億個上述成分 所有的基因都是一式兩份,染色體也是 每份約有32億個核苷酸 所以把兩份染色體加起來 就有超過六十億個核苷酸 如果你從一個細胞內,拿出所有的DNA 拉長後,大概足足有兩公尺 如果你拿出體內所有的DNA 足以從地球連接到月亮,然後再回到地球 往返幾千次,所以DNA之中能夠包含大量訊息
And so when you're copying this DNA molecule to pass it on, it's a pretty tough job. Imagine the longest book you can think of, "War and Peace." Now multiply it by 100. And imagine copying that by hand. And you're working away until late at night, and you're very, very careful, and you're drinking coffee and you're paying attention, but, occasionally, when you're copying this by hand, you're going to make a little typo, a spelling mistake -- substitute an I for an E, or a C for a T.
也因此,複製這些DNA,將訊息傳遞給後代,勢必是個艱鉅的任務 試想一本你能想到最厚重的書,比如戰爭與和平 乘上一百倍 然後你必須手抄複製這些內容 徹夜不眠 你小心翼翼地抄寫,喝著咖啡提神 你集中全副精神,但有的時候 當你完全以手抄複製 難免會抄錯--例如拼音錯誤 誤將I寫成E、C寫成T
Same thing happens to our DNA as it's being passed on through the generations. It doesn't happen very often. We have a proofreading mechanism built in. But when it does happen, and these changes get transmitted down through the generations, they become markers of descent. If you share a marker with someone, it means you share an ancestor at some point in the past, the person who first had that change in their DNA. And it's by looking at the pattern of genetic variation, the pattern of these markers in people all over the world, and assessing the relative ages when they occurred throughout our history, that we've been able to construct a family tree for everybody alive today.
相同情形也會發生在當DNA被一代一代傳下來的時候 這並不常發生,因為我們體內有自動校對機制 但是一旦發生,這些手誤將傳遞下去 一代接著一代,成為子子孫孫身上的標記 因此如果你跟某人的標記相同 那正說明你們可能血脈相連 能夠追溯到第一個抄錯的祖先 透過檢視遺傳變異的型態 現今全球人類共有的型態 分析這些標記從何時出現 是現今最新建立人類族譜的方式
These are two pieces of DNA that we use quite widely in our work. Mitochondrial DNA, tracing a purely maternal line of descent. You get your mtDNA from your mother, and your mother's mother, all the way back to the very first woman. The Y chromosome, the piece of DNA that makes men men, traces a purely paternal line of descent. Everybody in this room, everybody in the world, falls into a lineage somewhere on these trees. Now, even though these are simplified versions of the real trees, they're still kind of complicated, so let's simplify them. Turn them on their sides, combine them so that they look like a tree with the root at the bottom and the branches going up. What's the take-home message?
這邊有兩個我們研究中常用的DNA片段 一個是粒線體DNA,總是來自母系 你的粒線體DNA從母親那裏得到,你母親的粒線體DNA從你外祖母那裏得到 一路追下去,可以找到人類的第一個女性 還有另一個片段是Y染色體,即雄性染色體 總是來自父系 這演講廳裡所有的人,以及全世界所有的人 都能在這個族譜找到一個位置 即使我用的是簡化版本的族譜 還是相當複雜,所以我簡化一點來說明 將投影片轉個方向,看起來像棵樹 底下是樹根、上面是樹枝 其中說明了什麼?
Well, the thing that jumps out at you first is that the deepest lineages in our family trees are found within Africa, among Africans. That means that Africans have been accumulating this mutational diversity for longer. And what that means is that we originated in Africa. It's written in our DNA. Every piece of DNA we look at has greater diversity within Africa than outside of Africa. And at some point in the past, a sub-group of Africans left the African continent to go out and populate the rest of the world.
你最先注意到的 應該是最底層的家族關係 來自非洲 這代表非洲人身上 攜帶突變多樣性的時間最長 因此說明了人類起源於非洲,而且這個訊息寫在我們的DNA上 每個DNA片段,在非洲都可以找到更高的多樣性 過去的某個時間,一部分的非洲人 離開非洲大陸,遷移到其他地區定居
Now, how recently do we share this ancestry? Was it millions of years ago, which we might suspect by looking at all this incredible variation around the world? No, the DNA tells a story that's very clear. Within the last 200,000 years, we all share an ancestor, a single person -- Mitochondrial Eve, you might have heard about her -- in Africa, an African woman who gave rise to all the mitochondrial diversity in the world today.
問題是,這件事是在何時發生的? 幾百萬年前嗎? 如同我們從全世界如此多樣的人種來推測的一般? 答案是否,DNA的歷史書中明文記載 過去二十萬年中,我們仍擁有共同祖先,同一個人 粒線體夏娃,你或許聽過— 也出現在非洲 這位非洲女性,是現代各式各樣粒線體的起源
But what's even more amazing is that if you look at the Y-chromosome side, the male side of the story, the Y-chromosome Adam only lived around 60,000 years ago. That's only about 2,000 human generations, the blink of an eye in an evolutionary sense. That tells us we were all still living in Africa at that time. This was an African man who gave rise to all the Y chromosome diversity around the world. It's only within the last 60,000 years that we have started to generate this incredible diversity we see around the world. Such an amazing story. We're all effectively part of an extended African family.
但是更驚人的是 如果檢視Y染色體 父系起源— Y染色體亞當 距離我們只有六萬年之久 不過兩千的世代而已 對演化史而言,一眨眼的時間 這說明了,六萬年前,人類仍然生活在非洲 一位非洲男性 把Y染色體傳遞給全世界 在僅僅過去六萬年的時間裡 人種開始產生了難以置信的多樣性 多令人震驚的故事 我們每個人都是非洲大家族的成員之一
Now, that seems so recent. Why didn't we start to leave earlier? Why didn't Homo erectus evolve into separate species, or sub-species rather, human races around the world? Why was it that we seem to have come out of Africa so recently? Well, that's a big question. These "why" questions, particularly in genetics and the study of history in general, are always the big ones, the ones that are tough to answer.
那麼,問題來了:為什麼人類不是在更早之前離開非洲? 直立人為什麼沒有演化成其他物種? 或是其他亞種呢?為什麼直立人沒有成為現代人種? 為什麼我們這麼晚才從非洲遷移出來? 這是個大哉問,因為問的是為什麼 無論對遺傳學家或歷史學家,都是大問題 問題難度較高
And so when all else fails, talk about the weather. What was going on to the world's weather around 60,000 years ago? Well, we were going into the worst part of the last ice age. The last ice age started roughly 120,000 years ago. It went up and down, and it really started to accelerate around 70,000 years ago. Lots of evidence from sediment cores and the pollen types, oxygen isotopes and so on. We hit the last glacial maximum around 16,000 years ago, but basically, from 70,000 years on, things were getting really tough, getting very cold. The Northern Hemisphere had massive growing ice sheets. New York City, Chicago, Seattle, all under a sheet of ice. Most of Britain, all of Scandinavia, covered by ice several kilometers thick.
所以,當其他途徑都不通的時候,讓我們談一下全球氣候變遷的議題 六萬年前,全球氣候出了什麼狀況? 那時剛好是最近一個冰河時期最嚴重的時候 最近一個冰河時期始於十二萬年以前 氣候開始不穩定,來到約七萬年前時,更加惡化 從沉積物、 花粉類型、氧同位素等等的證據中都如此顯示 一萬六千年前,冰河時期進入高峰 然後在七萬年前左右,氣候條件變得極為嚴苛 溫度極低,整個北半球壟罩在冰層中 紐約、芝加哥、西雅圖 英國的絕大部分、整個斯堪地那維亞半島,全都被冰層覆蓋
Now, Africa is the most tropical continent on the planet -- about 85 percent of it lies between Cancer and Capricorn -- and there aren't a lot of glaciers here, except on the high mountains here in East Africa. So what was going on here? We weren't covered in ice in Africa. Rather, Africa was drying out at that time. This is a paleo-climatological map of what Africa looked like between 60,000 and 70,000 years ago, reconstructed from all these pieces of evidence that I mentioned before. The reason for that is that ice actually sucks moisture out of the atmosphere. If you think about Antarctica, it's technically a desert, it gets so little precipitation.
非洲--地球上最熱的大陸 百分之八十五的位置介於巨蟹座即摩羯座之間 卻沒有什麼冰層存在 除了在東非少數的高山地區之外 那裏發生了什麼事呢?人類沒有被冰層覆蓋 非洲大陸變得相當乾燥 這是遠古氣候分布圖 顯示非洲大陸約六萬到七萬年前的面貌 從我前面提過的各種證據拼湊出來的 非洲乾燥的原因是,冰其實會由大氣中吸收水分 想像一下南極,基本上是整片沙漠,降雨量幾乎是零
So the whole world was drying out. The sea levels were dropping. And Africa was turning to desert. The Sahara was much bigger then than it is now. And the human habitat was reduced to just a few small pockets, compared to what we have today. The evidence from genetic data is that the human population around this time, roughly 70,000 years ago, crashed to fewer than 2,000 individuals. We nearly went extinct. We were hanging on by our fingernails.
所以當時全球面臨乾旱 海平面下降,非洲大陸一片荒漠 撒哈拉沙漠的面積比今日大很多 與今日人類活動範圍相較 當時人類的居住地只剩下四散的小區域 遺傳證據顯示 七萬年前左右, 全球人口銳減至二千人以下 那時,我們瀕臨絕種,只差一步就完蛋了
And then something happened. A great illustration of it. Look at some stone tools. The ones on the left are from Africa, from around a million years ago. The ones on the right were made by Neanderthals, our distant cousins, not our direct ancestors, living in Europe, and they date from around 50,000 or 60,000 years ago. Now, at the risk of offending any paleoanthropologists or physical anthropologists in the audience, basically there's not a lot of change between these two stone tool groups. The ones on the left are pretty similar to the ones on the right. We are in a period of long cultural stasis from a million years ago until around 60,000 to 70,000 years ago. The tool styles don't change that much. The evidence is that the human way of life didn't change that much during that period.
接著有個事件發生,請看圖示 看看這些石器 左邊是非洲挖掘出來的,距今約一萬年前 右邊是尼安德塔人製作的,我們的遠房表親 不是我們的直系祖先,曾經住在歐洲 約五萬到六萬年前絕跡 接下來我要說的, 可能會冒犯在場的遠古人類學家或人類學家 這兩種石器,基本上沒有太多進化 左邊看起來跟右邊的很像 一百萬年前,直到六、七十萬年前 人類文明的進展處於停滯階段 使用的工具型態沒有什麼改變 這個證據說明,人類生活方式 在那個時期,變化不大
But then 50, 60, 70 thousand years ago, somewhere in that region, all hell breaks loose. Art makes its appearance. The stone tools become much more finely crafted. The evidence is that humans begin to specialize in particular prey species, at particular times of the year. The population size started to expand. Probably, according to what many linguists believe, fully modern language, syntactic language -- subject, verb, object -- that we use to convey complex ideas, like I'm doing now, appeared around that time. We became much more social. The social networks expanded.
但進入七萬、六萬、五萬年前,在非洲的某個地區 出現大幅度的變化,藝術開始發跡 石器雕刻變得更加精緻 這代表人類在那時 開始在每年的特定時候去獵食特定物種 人口數量開始擴增 根據語言學家的推測 完整的現代語言(句型)--包含主詞、動詞、受詞 就像我現在用來傳遞複雜概念的語言,也隨之出現 人類的社交性大增、社交關係更加複雜
This change in behavior allowed us to survive these worsening conditions in Africa, and they allowed us to start to expand around the world. We've been talking at this conference about African success stories. Well, you want the ultimate African success story? Look in the mirror. You're it. The reason you're alive today is because of those changes in our brains that took place in Africa -- probably somewhere in the region where we're sitting right now, around 60, 70 thousand years ago -- allowing us not only to survive in Africa, but to expand out of Africa. An early coastal migration along the south coast of Asia, leaving Africa around 60,000 years ago, reaching Australia very rapidly, by 50,000 years ago. A slightly later migration up into the Middle East. These would have been savannah hunters.
而這些行為的演化,幫助我們熬過惡劣的氣候 並且開始遷徙到全世界 這個演講已經談到許多人類在非洲的成功故事 想要聽一聽非洲成功故事的大結局嗎? 照個鏡子,就是你。今天你之所以生存在此 全來自於當時非洲大陸人腦的成功演化 搞不好就是我們現在所在之處 距今六、七萬年前 這些演化不但幫助人類存活下來,還從非洲遷移至全球 沿著非洲南部的海岸線 大約六萬年前離開非洲 五萬年前定居有些人開始定居澳洲 稍晚一點,一部分的人搬到中東 成為所謂的草原獵人
So those of you who are going on one of the post-conference tours, you'll get to see what a real savannah is like. And it's basically a meat locker. People who would have specialized in killing the animals, hunting the animals on those meat locker savannahs, moving up, following the grasslands into the Middle East around 45,000 years ago, during one of the rare wet phases in the Sahara. Migrating eastward, following the grasslands, because that's what they were adapted to live on.
如果有人參加本次演講之後的遊覽形成 將可見識到真正的草原獵人 簡單說,是一群不折不扣的肉食主義者 他們進化為一群捕獵專家 獵捕動物後,向北遷移 在四萬五千年前左右,沿著草原地區,遷移至中東地區 那時撒哈拉沙漠適逢一段難得的濕潤期 於是人類繼續沿著適合生存的草原 向東前進
And when they reached Central Asia, they reached what was effectively a steppe super-highway, a grassland super-highway. The grasslands at that time -- this was during the last ice age -- stretched basically from Germany all the way over to Korea, and the entire continent was open to them. Entering Europe around 35,000 years ago, and finally, a small group migrating up through the worst weather imaginable, Siberia, inside the Arctic Circle, during the last ice age -- temperature was at -70, -80, even -100, perhaps -- migrating into the Americas, ultimately reaching that final frontier.
來到中亞 他們沿著當時的「高速公路」 沿途都是草原構成的高速公路 當時仍處於冰河時期尾聲 一路從德國延伸到韓國,盡是草原 整片大陸都供他們去探索 三萬五千年前,人類棲地擴展至歐洲 最後,一小群人北上 前進西伯利亞 在冰河時期末,住進北極圈 當時氣溫大約華氏零下七、八十度,甚至一百度 最後終於來到美洲,就是人類遷徙路徑的終點
An amazing story, and it happened first in Africa. The changes that allowed us to do that, the evolution of this highly adaptable brain that we all carry around with us, allowing us to create novel cultures, allowing us to develop the diversity that we see on a whirlwind trip like the one I've just been on.
這個故事的動人之處是,一切源於非洲 且當時祖先的行為改變,使我們有機會 演化出高度適應力的大腦,而現在每一個人都擁有它 進而創造出新的文明 發展出高度多元性 就像我在這趟旋風式旅途中看到的一樣
Now, that story I just told you is literally a whirlwind tour of how we populated the world, the great Paleolithic wanderings of our species. And that's the story that I told a couple of years ago in my book, "The Journey of Man," and a film that we made with the same title. And as we were finishing up that film -- it was co-produced with National Geographic -- I started talking to the folks at NG about this work. And they got really excited about it. They liked the film, but they said, "You know, we really see this as kind of the next wave in the study of human origins, where we all came from, using the tools of DNA to map the migrations around the world. You know, the study of human origins is kind of in our DNA, and we want to take it to the next level. What do you want to do next?" Which is a great question to be asked by National Geographic.
其實,我剛剛講的人類歷史,就是一段旋風式旅程 一個人類散布至全球各地的奇蹟、一個舊石器時代的奇蹟 這也是我在幾年前 我的拙作「人類的旅程」一書中所講的故事 之後我們與國家地理頻道合作,翻拍成同名影集 當拍攝工作結束之際 我跟合作夥伴聊起這項研究計畫的始末 他們相當撼動,也非常喜歡拍攝成果,但是他們問: 你知道,我們真的覺得 利用DNA研究人類起源 及祖先遷徙的路徑,將帶動一股學術界的新潮流 既然人類起源都記錄在DNA之中 我們當然想更進一步了解 所以,你計畫下一步研究什麼? 國家地理頻道提出了個好問題
And I said, "Well, you know, what I've sketched out here is just that. It is a very coarse sketch of how we migrated around the planet. And it's based on a few thousand people we've sampled from, you know, a handful of populations around the world. Studied a few genetic markers, and there are lots of gaps on this map. We've just connected the dots. What we need to do is increase our sample size by an order of magnitude or more -- hundreds of thousands of DNA samples from people all over the world."
我說:我畫得這個草圖其實還很粗糙 只是大致說明人類遷移的路徑 而且是從數千人身上採樣的而已 相較於全世界人口,畢竟占少數 我們也只針對少數遺傳標籤做了研究,遷移地圖並不完整 我們頂多是將片段的資料串連起來 接著,當然需要增加樣本數,至少十倍 採集各地人類,成千上萬的DNA樣本
And that was the genesis of the Genographic Project. The project launched in April 2005. It has three core components. Obviously, science is a big part of it. The field research that we're doing around the world with indigenous peoples. People who have lived in the same location for a long period of time retain a connection to the place where they live that many of the rest of us have lost. So my ancestors come from all over northern Europe. I live in the Eastern Seaboard of North America when I'm not traveling. Where am I indigenous to? Nowhere really. My genes are all jumbled up. But there are people who retain that link to their ancestors that allows us to contextualize the DNA results.
這只是一個基因地理學計畫的起源 此計畫從2005年四月開始 包含三項核心領域,科學當然是一個重要的部分 另一個是各地原住民的實地考察 原住民指的是在同一地點,長時間生活的人種 他們與居住地的關係緊密 這是現代大多數人所缺乏的 比如我的祖先來自歐洲各地 當我不是在旅行時,我則居住在美國東岸 我的故鄉是哪裡呢?哪裡都不算,在遷移地圖上,我的基因位置到處都是 但是有些原住民,與祖先的連結還在 使我們能夠將DNA的結果串連起來
That's the focus of the field research, the centers that we've set up all over the world -- 10 of them, top population geneticists. But, in addition, we wanted to open up this study to anybody around the world. How often do you get to participate in a big scientific project? The Human Genome Project, or a Mars Rover mission.
這是實地考察的重點 我們已在世界各地設點 其中十個點,有頂尖的族群遺傳學家駐守 最後,我們希望對全球的人開放參與本計畫的機會 你有多少機會可以參與一項大型科學研究計畫? 如同「人類基因研究計畫」、「火星探索計畫」一般
In this case, you actually can. You can go onto our website, Nationalgeographic.com/genographic. You can order a kit. You can test your own DNA. And you can actually submit those results to the database, and tell us a little about your genealogical background, have the data analyzed as part of the scientific effort.
現在你有機會成為我們的一份子 上我們的網站:Nationalgeographic.com/genographic 訂購一套工具組,檢測自己的DNA 並將結果提交到我們的資料庫 輸入一些家族資料 我們就會當作研究計畫的一部分,分析你所提供的數據
Now, this is all a nonprofit enterprise, and so the money that we raise, after we cover the cost of doing the testing and making the kit components, gets plowed back into the project. The majority going to something we call the Legacy Fund. It's a charitable entity, basically a grant-giving entity that gives money back to indigenous groups around the world for educational, cultural projects initiated by them. They apply to this fund in order to do various projects, and I'll show you a couple of examples.
這完全是非營利的,因此我們募集到的所有經費 扣除研究成本及製作工具組的成本之後 就用之於本研究計畫 其中多數會捐給人類遺產保存基金會 這是個慈善性的基金會 把錢捐獻給全球需要的原住民 贊助他們自行發起的各項教育、文化發展活動 他們向這個基金會申請經費,來執行各種計畫 讓我提供一些實例
So how are we doing on the project? We've got about 25,000 samples collected from indigenous people around the world. The most amazing thing has been the interest on the part of the public; 210,000 people have ordered these participation kits since we launched two years ago, which has raised around five million dollars, the majority of which, at least half, is going back into the Legacy Fund.
我們計畫進行的如何呢? 目前已經得到的DNA樣本數共有兩萬五千個 來自世界各處的原住民 而震撼人心的是,來自各界的關注 從兩年前計畫開始以來 全球已經有二十一萬人訂購DNA測試組 因此我們募集了五百萬美元 至少一半以上的經費,也已經回饋給人類遺產保存基金會
We've just awarded the first Legacy Grants totaling around 500,000 dollars. Projects around the world -- documenting oral poetry in Sierra Leone, preserving traditional weaving patterns in Gaza, language revitalization in Tajikistan, etc., etc. So the project is going very, very well, and I urge you to check out the website and watch this space.
我們才剛捐出一筆五十萬美元 作為保存席拉里昂口傳詩歌 、保護加沙傳統編織 或復興塔克亞語等相關文化保存活動之用 目前計畫進行得非常順利 我在這裡,鼓勵各位去瀏覽我們的網站,並持續關注這項研究
Thank you very much. (Applause)
非常感謝各位! (掌聲)