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  • Now, extinction is a different kind of death.

    物種滅絕是一種不一樣的死亡

  • It's bigger.

    它的規模更大

  • We didn't really realize that until 1914,

    但直到 1914 年,當最後一隻旅鴿 ——

  • when the last passenger pigeon, a female named Martha,

    一隻名叫瑪莎的母鳥 —— 在辛辛那提動物園中去世時,

  • died at the Cincinnati zoo.

    我們才瞭解到這份震撼

  • This had been the most abundant bird in the world

    牠們曾是世界上數量最多的鳥類

  • that'd been in North America for six million years.

    存活於北美洲六百萬年

  • Suddenly it wasn't here at all.

    突然間就消失了

  • Flocks that were a mile wide and 400 miles long

    旅鴿鳥群曾達 1 英里寬並綿延 400 英里

  • used to darken the sun.

    甚至可以遮蔽太陽

  • Aldo Leopold said this was a biological storm,

    阿爾多.李奧帕德曾如此形容:

  • a feathered tempest.

    這是一場生物風暴、一場飛羽旋風

  • And indeed it was a keystone species

    牠們也確實是關鍵物種

  • that enriched the entire eastern deciduous forest,

    盤踞美東的落葉林

  • from the Mississippi to the Atlantic,

    從密西西比河到大西洋

  • from Canada down to the Gulf.

    從加拿大一路到墨西哥灣

  • But it went from five billion birds to zero in just a couple decades.

    但從五十億隻歸零 卻只花了數十年的時間

  • What happened?

    發生什麼事呢?

  • Well, commercial hunting happened.

    嗯,發生了商業性的獵殺

  • These birds were hunted for meat that was sold by the ton,

    這種鳥類被獵殺並成噸地賣入肉品市場

  • and it was easy to do because when those big flocks

    牠們成群的飛行,讓獵殺易如反掌

  • came down to the ground, they were so dense

    當牠們接近地面時,數百名獵人

  • that hundreds of hunters and netters could show up

    可以輕而易舉地從如此密集的鳥群中

  • and slaughter them by the tens of thousands.

    獵殺到成千上萬的獵物

  • It was the cheapest source of protein in America.

    牠們曾是美國最廉價的蛋白質來源

  • By the end of the century, there was nothing left

    到 19 世紀末葉,牠們就從地球上消失了

  • but these beautiful skins in museum specimen drawers.

    只剩披蓋華羽的標本躺在博物館中

  • There's an upside to the story.

    但這故事仍有光明的一面

  • This made people realize that the same thing

    這讓人類意識到同樣的狀況

  • was about to happen to the American bison,

    也將發生在美洲水牛身上

  • and so these birds saved the buffalos.

    所以這些鳥的滅絕救了水牛

  • But a lot of other animals weren't saved.

    但仍有許多我們保護不及的動物

  • The Carolina parakeet was a parrot that lit up backyards everywhere.

    卡羅萊納長尾鸚鵡 曾是點亮每家後院的嬌客

  • It was hunted to death for its feathers.

    卻因羽毛需求而被獵殺殆盡

  • There was a bird that people liked on the East Coast called the heath hen.

    曾經有種叫北美松雞的鳥被東岸人喜愛

  • It was loved. They tried to protect it. It died anyway.

    因為牠令人喜歡,人們試圖保護牠 但牠們最終還是滅絕了

  • A local newspaper spelled out, "There is no survivor,

    地方報紙曾說:「沒有生還,也沒有未來,

  • there is no future, there is no life to be recreated in this form ever again."

    世界再也沒辦法創造出這樣的生命。」

  • There's a sense of deep tragedy that goes with these things,

    當物種消失時,總是有種深沈的哀傷蔓延

  • and it happened to lots of birds that people loved.

    許多受人喜愛的鳥類已遭此命運

  • It happened to lots of mammals.

    同樣狀況也發生在哺乳動物身上

  • Another keystone species is a famous animal

    另一個關鍵物種是有名的動物

  • called the European aurochs.

    歐洲野牛

  • There was sort of a movie made about it recently.

    最近甚至有部關於牠們的電影

  • And the aurochs was like the bison.

    這些野牛很像水牛

  • This was an animal that basically kept the forest

    基本上,這種動物的生態功能

  • mixed with grasslands across the entire Europe and Asian continent,

    使得歐亞大陸的森林之間保有草原

  • from Spain to Korea.

    牠們分佈從西班牙到韓國

  • The documentation of this animal goes back

    而人類關於這種動物的記載

  • to the Lascaux cave paintings.

    可以回溯到拉斯科岩洞畫的年代

  • The extinctions still go on.

    許多動物仍陸續滅絕

  • There's an ibex in Spain called the bucardo.

    一種分佈在西班牙,名為布卡多山羊的野山羊

  • It went extinct in 2000.

    於 2000 年滅絕

  • There was a marvelous animal, a marsupial wolf

    也有一些令人驚嘆的物種,像是袋狼

  • called the thylacine in Tasmania, south of Australia,

    牠們在澳洲的塔斯馬尼亞州

  • called the Tasmanian tiger.

    又稱塔斯馬尼亞狼或塔斯馬尼亞虎

  • It was hunted until there were just a few left to die in zoos.

    牠們也逃不過獵殺,最後幾隻在動物園中死去

  • A little bit of film was shot.

    這是一小段影片

  • Sorrow, anger, mourning.

    沈重、憤怒、悲傷

  • Don't mourn. Organize.

    但別悲傷,振作起來

  • What if you could find out that, using the DNA in museum specimens,

    如果你發現利用博物館標本

  • fossils maybe up to 200,000 years old

    或是 20 萬年前化石中的 DNA

  • could be used to bring species back,

    可以讓這些物種復活

  • what would you do? Where would you start?

    你會怎麼做呢? 你又會從何做起?

  • Well, you'd start by finding out if the biotech is really there.

    你可能會先確定,生物技術是否達得到要求

  • I started with my wife, Ryan Phelan,

    我則是從我太太萊恩.費倫那開始

  • who ran a biotech business called DNA Direct,

    她經營一家叫 DNA Direct 的生技公司

  • and through her, one of her colleagues, George Church,

    透過她,我認識了她同事喬治.邱奇

  • one of the leading genetic engineers

    他也是位著迷於旅鴿的

  • who turned out to be also obsessed with passenger pigeons

    頂尖基因工程師

  • and a lot of confidence

    他對他所使用的方法深具信心

  • that methodologies he was working on

    他對他所使用的方法深具信心

  • might actually do the deed.

    並認為他可以讓物種復活

  • So he and Ryan organized and hosted a meeting

    所以他和萊恩策劃並主持了一個會議

  • at the Wyss Institute in Harvard bringing together

    在哈佛的維斯學院招集了一批

  • specialists on passenger pigeons, conservation ornithologists, bioethicists,

    旅鴿專家、鳥類保育學家、生物倫理學家

  • and fortunately passenger pigeon DNA had already been sequenced

    而且很幸運的是旅鴿的 DNA 已經被

  • by a molecular biologist named Beth Shapiro.

    一名叫做貝絲.夏皮羅的分子生物學家完成定序

  • All she needed from those specimens at the Smithsonian

    而她只用了保存在史密森納研究院

  • was a little bit of toe pad tissue,

    標本中的一小塊腳部組織

  • because down in there is what is called ancient DNA.

    因為裡面含有原始 DNA

  • It's DNA which is pretty badly fragmented,

    DNA 已經碎裂成片段

  • but with good techniques now, you can basically reassemble the whole genome.

    利用現在的技術,你可以重組成完整的基因序列

  • Then the question is, can you reassemble,

    問題在於你能不能利用

  • with that genome, the whole bird?

    基因體生出隻健全的鳥?

  • George Church thinks you can.

    喬治.邱奇認為這可以達到

  • So in his book, "Regenesis," which I recommend,

    在他寫的、也是我強力推薦的 «重生» 中

  • he has a chapter on the science of bringing back extinct species,

    有一章解釋了復活滅絕物種的技術

  • and he has a machine called

    這個機器被他稱為:

  • the Multiplex Automated Genome Engineering machine.

    多樣化自動基因體建構機

  • It's kind of like an evolution machine.

    這項技術和演化的機制類似

  • You try combinations of genes that you write

    你將不同組合的基因送入細胞

  • at the cell level and then in organs on a chip,

    從細胞層級到組織層級

  • and the ones that win, that you can then put

    再把成功存活下來的組織

  • into a living organism. It'll work.

    送入代理孕母體內,它就會成功

  • The precision of this, one of George's famous unreadable slides,

    從喬治難以辨識的紀錄中

  • nevertheless points out that there's a level of precision here

    我們可以知道這項技術的精確度

  • right down to the individual base pair.

    達到鹼基對的層級

  • The passenger pigeon has 1.3 billion base pairs in its genome.

    候鴿基因體包含 13 億對鹼基

  • So what you're getting is the capability now

    所以你現在能做的是

  • of replacing one gene with another variation of that gene.

    把一個基因用它的對偶基因取代

  • It's called an allele.

    (譯注:這是用來解決原始基因序列上破碎、缺失的問題)

  • Well that's what happens in normal hybridization anyway.

    這在正常的精卵結合過程中也會發生

  • So this is a form of synthetic hybridization of the genome

    所以,我們可用和滅絕物種

  • of an extinct species

    最接近的物種

  • with the genome of its closest living relative.

    組合並修復滅絕物種的基因體

  • Now along the way, George points out that

    在此過程中,喬治指出

  • his technology, the technology of synthetic biology,

    他所使用的合成生物學技術

  • is currently accelerating at four times the rate of Moore's Law.

    現在成長速度是莫爾定律的四倍

  • It's been doing that since 2005, and it's likely to continue.

    這從 2005 開始,也很有可能一直延續下去

  • Okay, the closest living relative of the passenger pigeon

    最接近旅鴿的存活物種是帶尾鴿

  • is the band-tailed pigeon. They're abundant. There's some around here.

    他們數量龐大,在這附近也有

  • Genetically, the band-tailed pigeon already is

    從基因層面來說,帶尾鴿幾乎是活著的旅鴿

  • mostly living passenger pigeon.

    牠們的基因體中只有一些是帶尾鴿特有的序列

  • There's just some bits that are band-tailed pigeon.

    牠們的基因體中只有一些是帶尾鴿特有的序列

  • If you replace those bits with passenger pigeon bits,

    如果你將這些序列以旅鴿特有的序列取代

  • you've got the extinct bird back, cooing at you.

    你就有一隻已經滅絕旅鴿對你咕咕叫

  • Now, there's work to do.

    現在需要著手進行的是:

  • You have to figure out exactly what genes matter.

    你必須分辨出哪些基因是重要的

  • So there's genes for the short tail in the band-tailed pigeon,

    像是帶尾鴿擁有短尾的基因

  • genes for the long tail in the passenger pigeon,

    而旅鴿則是表現長尾的基因

  • and so on with the red eye, peach-colored breast, flocking, and so on.

    還有紅眼、桃紅色的胸部和群集行為等基因

  • Add them all up and the result won't be perfect.

    將這些都加在一起,結果不會是完美的

  • But it should be be perfect enough,

    但應該就近乎完美了

  • because nature doesn't do perfect either.

    自然界中也沒有「完美」的作品

  • So this meeting in Boston led to three things.

    所以,在波士頓的會議中決定了三件事

  • First off, Ryan and I decided to create a nonprofit

    首先,我和萊恩創立了個非營利組織

  • called Revive and Restore that would push de-extinction generally

    這個名為「復活與保存」的組織致力

  • and try to have it go in a responsible way,

    以付責任的方式推動「反滅絕」

  • and we would push ahead with the passenger pigeon.

    而我們將先從旅鴿做起

  • Another direct result was a young grad student named Ben Novak,

    另一項結果是本.諾瓦克,一位年輕研究生

  • who had been obsessed with passenger pigeons since he was 14

    他從 14 歲起就被旅鴿所深深著迷

  • and had also learned how to work with ancient DNA,

    而且在學會如何操作原始 DNA 後

  • himself sequenced the passenger pigeon,

    他利用家人和朋友的金援

  • using money from his family and friends.

    完成了旅鴿基因體定序

  • We hired him full-time.

    我們雇用了他

  • Now, this photograph I took of him last year at the Smithsonian,

    這是一張去年在史密森納我幫他照的照片

  • he's looking down at Martha,

    照片中他低頭看著瑪莎 ——

  • the last passenger pigeon alive.

    世界上最後一隻旅鴿

  • So if he's successful, she won't be the last.

    如果他成功的話,她就不會是最後一隻

  • The third result of the Boston meeting was the realization

    波士頓會議的第三項結果是

  • that there are scientists all over the world

    讓我們瞭解到世界上有許多科學家

  • working on various forms of de-extinction,

    在進行不同型式的反滅絕

  • but they'd never met each other.

    但他們素未謀面

  • And National Geographic got interested

    而國家地理頻道對此感到興趣

  • because National Geographic has the theory that

    因為他們有個想法

  • the last century, discovery was basically finding things,

    就是上世紀的發現是為了尋找未知

  • and in this century, discovery is basically making things.

    而這個世紀是在創造發明

  • De-extinction falls in that category.

    而反滅絕符合此條件

  • So they hosted and funded this meeting. And 35 scientists,

    所以他們資助並主辦了這場會議

  • they were conservation biologists and molecular biologists,

    讓 35 位保育生物學家和分子生物學家

  • basically meeting to see if they had work to do together.

    見面並討論合作機會

  • Some of these conservation biologists are pretty radical.

    其中一些保育生物學家非常激進

  • There's three of them who are not just re-creating ancient species,

    其中三人不只要讓古生物復活

  • they're recreating extinct ecosystems

    他們更希望在北西伯利亞、荷蘭和夏威夷

  • in northern Siberia, in the Netherlands, and in Hawaii.

    恢復已經消失的生態系統

  • Henri, from the Netherlands,

    來自荷蘭的亨利

  • with a Dutch last name I won't try to pronounce,

    嗯,我不會試著說他的荷文姓氏

  • is working on the aurochs.

    在做歐洲野牛

  • The aurochs is the ancestor of all domestic cattle,

    歐洲野牛是所有被馴養牛種的祖先

  • and so basically its genome is alive, it's just unevenly distributed.

    所以牠的基因體還存在, 只是不平均的散佈在不同品種裡

  • So what they're doing is working with seven breeds

    所以他們利用七個原始、強韌

  • of primitive, hardy-looking cattle like that Maremmana primitivo on the top there

    和上圖原牛相似的品種

  • to rebuild, over time, with selective back-breeding,

    利用篩選性的繁殖

  • the aurochs.

    希望可以讓歐洲野牛重現

  • Now, re-wilding is moving faster in Korea

    現在野放在韓國推展得

  • than it is in America,

    比美國更為快速

  • and so the plan is, with these re-wilded areas all over Europe,

    所以我們計畫將野牛引進歐洲的野放區

  • they will introduce the aurochs to do its old job,

    讓牠們扮演原有的生態功能

  • its old ecological role,

    牠們原本在生態系中扮演的角色

  • of clearing the somewhat barren, closed-canopy forest

    讓原本茂密森林下的貧脊土壤

  • so that it has these biodiverse meadows in it.

    重現多樣化的草原植被

  • Another amazing story

    另一個令人驚歎的故事

  • came from Alberto Fernández-Arias.

    是來自阿貝圖.費爾南斯.阿里

  • Alberto worked with the bucardo in Spain.

    阿貝圖在西班牙研究布卡多山羊

  • The last bucardo was a female named Celia

    最後一隻是名叫西麗亞的母羊

  • who was still alive, but then they captured her,

    當研究員捕捉牠時牠還健在

  • they got a little bit of tissue from her ear,

    當時他們從牠耳朵取得一小塊組織

  • they cryopreserved it in liquid nitrogen,

    並冷凍保存於液態氮中後

  • released her back into the wild,

    將牠野放

  • but a few months later, she was found dead under a fallen tree.

    但數個月後發現牠被樹木壓死

  • They took the DNA from that ear,

    他們利用牠耳朵中的 DNA

  • they planted it as a cloned egg in a goat,

    恢復成受精卵的形式並殖入山羊

  • the pregnancy came to term,

    當孕期結束

  • and a live baby bucardo was born.

    活生生的布卡多山羊就出生了

  • It was the first de-extinction in history.

    這是歷史上第一個反滅絕的實例

  • (Applause)

    (掌聲)

  • It was short-lived.

    但牠活的不久

  • Sometimes interspecies clones have respiration problems.

    有時候跨種的複製會造成呼吸系統的問題

  • This one had a malformed lung and died after 10 minutes,

    這隻肺臟發育不全的羊只存活了 10 分鐘

  • but Alberto was confident that

    但阿貝圖對此深具信心

  • cloning has moved along well since then,

    因為動物複製技術已有長足進步

  • and this will move ahead, and eventually

    未來終究會更加發達

  • there will be a population of bucardos

    他相信未來會有成群的布卡多山羊

  • back in the mountains in northern Spain.

    重返西班牙北部的山區

  • Cryopreservation pioneer of great depth is Oliver Ryder.

    冷凍保存的先驅奧利弗.雷德

  • At the San Diego zoo, his frozen zoo

    在聖地牙哥動物園中

  • has collected the tissues from over 1,000 species

    他的冰凍園區在過去 35 年內

  • over the last 35 years.

    蒐集了超過 1 千種物種的組織

  • Now, when it's frozen that deep,

    當冰封在低溫 ——

  • minus 196 degrees Celsius,

    攝氏 -196 度

  • the cells are intact and the DNA is intact.

    細胞和其中的 DNA 都可以完整保存

  • They're basically viable cells,

    它們基本上都是能培養的細胞

  • so someone like Bob Lanza at Advanced Cell Technology

    先進細胞科技公司的鮑勃.蘭扎

  • took some of that tissue from an endangered animal

    從瀕臨絕種的爪哇野牛的冷凍組織中

  • called the Javan banteng, put it in a cow,

    取了一些殖入母乳牛

  • the cow went to term, and what was born

    當母牛孕期屆滿

  • was a live, healthy baby Javan banteng,

    一隻健康的爪哇野牛寶寶就誕生了

  • who thrived and is still alive.

    牠仍健在,也在持續成長中

  • The most exciting thing for Bob Lanza

    最讓鮑博興奮的是

  • is the ability now to take any kind of cell

    現在可將任何細胞誘導成全能幹細胞

  • with induced pluripotent stem cells

    並將其分化成如精子、卵子

  • and turn it into germ cells, like sperm and eggs.

    這類生殖細胞的技術

  • So now we go to Mike McGrew

    現在我們來介紹麥克.麥格羅

  • who is a scientist at Roslin Institute in Scotland,

    他是一位在蘇格蘭羅斯林研究所的科學家

  • and Mike's doing miracles with birds.

    麥克在鳥類上展現奇蹟

  • So he'll take, say, falcon skin cells, fibroblast,

    他會拿獵鷹的皮膚細胞,例如纖維母細胞

  • turn it into induced pluripotent stem cells.

    讓它恢復成全能幹細胞

  • Since it's so pluripotent, it can become germ plasm.

    因為它具有全能性,所以也可分化成種質

  • He then has a way to put the germ plasm

    讓後他有種方法可以將種質

  • into the embryo of a chicken egg

    送入雞蛋的胚胎中

  • so that that chicken will have, basically,

    所以這隻雞將會長出

  • the gonads of a falcon.

    獵鷹的生殖腺

  • You get a male and a female each of those,

    當你把牠們湊成對後

  • and out of them comes falcons.

    就可以生出獵鷹了

  • (Laughter)

    (笑聲)

  • Real falcons out of slightly doctored chickens.

    從改造的雞生出獵鷹

  • Ben Novak was the youngest scientist at the meeting.

    本.諾瓦克是會議中最年輕的科學家

  • He showed how all of this can be put together.

    他預見如何讓這些技術銜接在一起

  • The sequence of events: he'll put together the genomes

    流程如下:他會先利用帶尾鴿

  • of the band-tailed pigeon and the passenger pigeon,

    和旅鴿的基因體放在一起

  • he'll take the techniques of George Church

    再利用喬治.邱奇的技術

  • and get passenger pigeon DNA,

    修復旅鴿的 DNA

  • the techniques of Robert Lanza and Michael McGrew,

    羅伯特.蘭扎和麥克.麥格羅的技術

  • get that DNA into chicken gonads,

    則可以將 DNA 送入雞的生殖腺

  • and out of the chicken gonads get passenger pigeon eggs, squabs,

    並生出旅鴿蛋、孵化成雛鴿

  • and now you're getting a population of passenger pigeons.

    你就可得到旅鴿族群

  • It does raise the question of,

    這可能會有個問題:

  • they're not going to have passenger pigeon parents

    沒有旅鴿親鳥

  • to teach them how to be a passenger pigeon.

    如何教導乳鴿成為一隻真正的旅鴿?

  • So what do you do about that?

    你會怎麼解決這個問題?

  • Well birds are pretty hard-wired, as it happens,

    還好大部份鳥類行為

  • so most of that is already in their DNA,

    都包還含在牠們的 DNA 裡

  • but to supplement it, part of Ben's idea

    但為了保險起見,他提出一個想法:

  • is to use homing pigeons

    利用信鴿

  • to help train the young passenger