I do want to test this question we're all interested in:

試問一個大家都有興趣的問題

Does extinction have to be forever?

絕種這回事是否絕對是永久的呢?

I'm focused on two projects I want to tell you about.

我想告訴你們兩個我所關注的計畫

One is the Thylacine Project.

一個是關於袋狼

The other one is the Lazarus Project,

一個是拉薩魯計劃

and that's focused on the gastric-brooding frog.

一個關於胃育溪蟾的計畫

And it would be a fair question to ask,

大家可能會問

why have we focused on these two animals?

為什麼我們要關注在這兩種動物上

Well, point number one, each of them represents a unique family of its own.

首先是因為牠們能

We've lost a whole family.

代表各自所屬的特殊的科別

That's a big chunk of the global genome gone.

我們已經失去這科別中所有的成員

I'd like it back.

一個不小的全面性基因庫就此消失

The second reason is that we killed these things.

而我想要它再展從前之盛況

In the case of the thylacine, regrettably, we shot every one that we saw.

第二個原因是因為 我們就是這個問題的肇事者

We slaughtered them.

在袋狼的例子中，很不幸地

In the case of the gastric-brooding frog, we may have "fungicided" it to death.

我們屠殺了牠們

There's a dreadful fungus that's moving through the world

而在胃育溪蟾的例子中

that's called the chytrid fungus,

我們可能讓"真菌"殺了牠們

and it's nailing frogs all over the world.

有一種散布於世界上的可怕真菌

We think that's probably what got this frog,

叫做"蛙壺菌"

and humans are spreading this fungus.

它感染了遍佈世界各地的蛙類

And this introduces a very important ethical point,

我們認為這也許是胃育溪蟾滅絕的主因

and I think you will have heard this many times

而人類正是散播這些真菌的始作俑者

when this topic comes up.

而這引出了很重要的道德觀點

What I think is important

我相信你們已經聽過很多次

is that, if it's clear that we exterminated these species,

當滅絕的議題被提出來

then I think we not only have a moral obligation

我認為重要的是

to see what we can do about it,

我們過去是否清楚地研究這些物種

but I think we've got a moral imperative to try to do something, if we can.

此外我認為我們不僅因為義務

OK. Let me talk to you about the Lazarus Project.

看看我們還能做什麼，只要我們有能力

It's a frog. And you think, frog.

我們有道德上的責任必須試著做些什麼

Yeah, but this was not just any frog.

那我們來談談拉魯薩計畫

Unlike a normal frog, which lays its eggs in the water

這是青蛙，是的，青蛙

and goes away and wishes its froglets well,

但卻不是一般的青蛙

this frog swallowed its fertilized eggs,

不像一般的青蛙只是把蛋產在水裡

swallowed them into the stomach, where it should be having food,

然後就任其生長

didn't digest the eggs, and turned its stomach into a uterus.

胃育溪蟾會把受精卵

In the stomach, the eggs went on to develop into tadpoles,

吞到本來應該要裝滿食物胃中

and in the stomach, the tadpoles went on to develop into frogs,

卻不消化這些蛋

and they grew in the stomach

而把胃當成子宮

until eventually the poor old frog was at risk of bursting apart.

蛋便在胃裡發育成蝌蚪

It has a little cough and a hiccup, and out comes sprays of little frogs.

並且就在胃裡長成幼蛙

Now, when biologists saw this, they were agog.

他們在胃中長大直到

They thought, this is incredible.

可憐的母蛙冒著被撐破的危險

No animal, let alone a frog, has been known to do this,

在咳嗽或打嗝時使得

to change one organ in the body into another.

幼蛙被噴出

And you can imagine the medical world went nuts over this as well.

現在，當生物學家看到這時 他們感到無比的震撼

If we could understand

紛紛不敢置信

how that frog is managing the way its tummy works,

除了青蛙之外，從來沒有動物能做到這件事

is there information here that we need to understand

改變一個器官的功能

or could usefully use to help ourselves?

可想而知醫界限入瘋狂

Now, I'm not suggesting we want to raise our babies in our stomach,

如果我們能夠了解 胃育溪蟾的胃如何運作

but I am suggesting it's possible

那麼將會有許多資訊

we might want to manage gastric secretion in the gut.

我們必須盡一步了解甚至運用

And just as everybody got excited about it, bang!

來幫助更多人

It was extinct.

我並不是說要把嬰兒養在胃裡

I called up my friend,

而是我們可能可以了解

Professor Mike Tyler in the University of Adelaide.

胃在內臟裡的分泌物

He was the last person who had this frog, a colony of these things, in his lab.

當大家都對此感到興奮時，碰

And I said, "Mike, by any chance --" This was 30 or 40 years ago.

胃育溪蟾絕種了

"By any chance had you kept any frozen tissue of this frog?"

我打給我朋友，邁克泰勒教授

And he thought about it,

在阿德雷得大學

and he went to his deep freezer, minus 20 degrees centigrade,

他是最後一個曾有這種青蛙的人

and he poured through everything in the freezer,

在他的實驗室中曾有ㄧ群這種青蛙

and there in the bottom was a jar and it contained tissues of these frogs.

我說"麥克，有無可能

This was very exciting,

這是30到40年前的事

but there was no reason why we should expect that this would work,

有無可能你還留著胃育溪蟾的組織

because this tissue had not had any antifreeze put in it,

他想了想，到了他那負二十度

cryoprotectants, to look after it when it was frozen.

的大冰箱

And normally, when water freezes, as you know, it expands,

把所有東西都拿出來

and the same thing happens in a cell.

在最底層是一個罐子

If you freeze tissues, the water expands, damages or bursts the cell walls.

裝著一些青蛙的組織

Well, we looked at the tissue under the microscope.

這非常令人振奮

It actually didn't look bad. The cell walls looked intact.

但我們確沒有理由確信這會行的通

So we thought, let's give it a go.

因為這組織沒有摻入防凍劑

What we did is something called somatic cell nuclear transplantation.

低溫防護劑，確保冷凍樣品的狀況

We took the eggs of a related species, a living frog,

普遍來說，水結冰時會膨脹

and we inactivated the nucleus of the egg.

一樣的事也發生在細胞中

We used ultraviolet radiation to do that.

若將組織冰動，其中的水會膨脹

And then we took the dead nucleus from the dead tissue of the extinct frog

傷害或撐破細胞壁

and we inserted those nuclei into that egg.

當我們從顯微鏡下看組織時

Now, by rights, this is kind of like a cloning project,

竟然看起來不差。細胞壁完好無缺

like what produced Dolly,

於是我們想，試試無妨

but it's actually very different,

我們所作的稱為

because Dolly was live sheep into live sheep cells.

體細胞核移植

That was a miracle, but it was workable.

我們拿了一隻活的，有血緣關係的卵

What we're trying to do is take a dead nucleus from an extinct species

然後使其核失去作用

and put it into a completely different species and expect that to work.

我們是用紫外光做到的

Well, we had no real reason to expect it would,

再把胃育溪蟾的核 從死去組織中抽出來

and we tried hundreds and hundreds of these.

注入失去核的活卵中

And just last February, the last time we did these trials,

這樣看起來的確有點像 基因復製的過程

I saw a miracle starting to happen.

像桃莉羊那樣，但其實是很不一樣的

What we found was most of these eggs didn't work,

因為桃莉是活體之間的移植

but then suddenly, one of them began to divide.

那是一個行得通的奇蹟

That was so exciting.

而我們做的是取出 絕種物種的死細胞核

And then the egg divided again. And then again.

然後放進完全不同的物種 並期許牠能作用

And pretty soon, we had early-stage embryos

我們是沒有理由期望牠會成功

with hundreds of cells forming those.

在試了幾百次後

We even DNA-tested some of these cells,

就在去年二月，最後ㄧ次的試驗

and the DNA of the extinct frog is in those cells.

我看到了奇蹟的發生

So we're very excited. This is not a tadpole. It's not a frog.

大部份的卵儘管不能作用

But it's a long way along the journey

卻有一個突然開始分裂了

to producing, or bringing back, an extinct species.

當它又分裂時著實令人興奮

And this is news.

接著它又不斷地分裂，很快地我們有了一個

We haven't announced this publicly before.

以數百個細胞組成的早期胚胎

We're excited.

我們甚至對一些細胞進行DNA測試

We've got to get past this point.

的確在那些細胞中 含有胃育溪蟾的DNA

We now want this ball of cells to start to gastrulate,

我們感到非常興奮。那還不是蝌蚪

to turn in so that it will produce the other tissues.

也還不是青蛙。但它是一個讓絕種的胃育溪蟾

It'll go on and produce a tadpole and then a frog.

起死回生的偉大旅程

Watch this space.

這可是一個我們從未宣布的大新聞

I think we're going to have this frog hopping

對於將跨入令一個不同的階段 我們感到鼓舞

glad to be back in the world again.

我們期望這團細胞球體 能進入原腸胚階段

(Applause)

以繼續繁殖其他組織

Thank you.

最後將成為蝌蚪然後是青蛙

(Applause)

看看這空間，我相信我們能

We haven't done it yet, but keep the applause ready.

讓胃育溪蟾在這裡活潑的跳來跳去

The second project I want to talk to you about is the Thylacine Project.

謝謝

The thylacine looks a bit, to most people, like a dog,

我們還沒做到，但那些掌聲將來會用到的

or maybe like a tiger, because it has stripes.

另一個計畫是袋狼的計劃

But it's not related to any of those. It's a marsupial.

牠對大多數的人來說 看起來有點像一隻狗

It raised its young in a pouch, like a koala or a kangaroo would do,

或老虎，因為牠有斑紋

and it has a long history, a long, fascinating history,

但牠跟那些一點關係都沒有

that goes back 25 million years.

牠是有袋類。從小在袋中長大

But it's also a tragic history.

就像無尾熊或袋鼠

The first one that we see occurs in the ancient rain forests of Australia

而牠有一個可以追溯到2500萬年前

about 25 million years ago,

久遠而美好的歷史

and the National Geographic Society

但那卻也是一個悲慘的歷史

is helping us to explore these fossil deposits.

第一件事是發生在2500萬年前

This is Riversleigh.

澳洲的古雨林裡

In those fossil rocks are some amazing animals.

國家地理協會幫忙我們

We found marsupial lions.

去探勘化石沉積物。這裡是 Riverleigh

We found carnivorous kangaroos.

在化石中有些令人驚艷的動物

It's not what you usually think about as a kangaroo,

我們找到有袋的獅子

but these are meat-eating kangaroos.

肉食性的袋鼠

We found the biggest bird in the world,

並不是平常我們所見

bigger than that thing that was in Madagascar,

而是真的吃肉的袋鼠

and it too was a flesh eater.

還有全世界最大的鳥類

It was a giant, weird duck.

比馬達加斯加的還大

And crocodiles were not behaving at that time either.

牠也是一種巨大而奇怪的肉食性鴨子

You think of crocodiles as doing their ugly thing,

連鱷魚當時的行為都是不太一樣的

sitting in a pool of water.

你也許認為鱷魚就是髒髒的

These crocodiles were actually out on the land

待在水裡

and they were even climbing trees and jumping on prey on the ground.

牠們其實是在陸地上的

We had, in Australia, drop crocs. They really do exist.

甚至爬到樹上然後

(Laughter)

撲到獵物身上

But what they were dropping on was not only other weird animals

這種會跳下來的鱷魚確實存在過，就在澳洲

but also thylacines.

而牠們撲倒的其中一種生物

There were five different kinds of thylacines in those ancient forests,

便是袋狼

and they ranged from great big ones to middle-sized ones

在那原始林中有五種不同的袋狼

to one that was about the size of a chihuahua.

從極大的到中型的

Paris Hilton would have been able

到小型如吉娃娃狗的尺寸

to carry one of these things around in a little handbag,

連Paris Hilton都放一隻

until a drop croc landed on her.

在小手提包中帶著走

At any rate, it was a fascinating place,

直到一隻鱷魚飛撲在她身上

but unfortunately, Australia didn't stay this way.

無論如何，那是個令人驚奇的地方

Climate change has affected the world for a long period of time,

但不幸地，澳洲並未繼續保持下去

and gradually, the forests disappeared, the country began to dry out,

氣候變遷已經影響這個世界好一陣子了

and the number of kinds of thylacines began to decline,

而雨林日漸消失

until by five million years ago,

氣候逐漸乾燥

only one left.

袋狼數量也隨之銳減

By 10,000 years ago, they had disappeared from New Guinea,

到了五百萬年前只剩下一隻

and unfortunately, by 4,000 years ago, somebodies, we don't know who this was,

一萬年前在新幾內亞

introduced dingoes -- this is a very archaic kind of a dog --

絕種了，並且不幸地

into Australia.

四千年前

And as you can see,

有不知名的人把澳洲野犬

dingoes are very similar in their body form to thylacines.

一種古代的狗，引進澳洲

That similarity meant they probably competed.

如你所見

They were eating the same kinds of foods.

身形上兩者非常相似

It's even possible that aborigines were keeping some of these dingoes as pets,

也就是說牠們曾是競爭關係

and therefore they may have had an advantage in the battle for survival.

吃同樣的食物

All we know is, soon after the dingoes were brought in,

甚至可能從前原住民曾經豢養

thylacines were extinct in the Australian mainland,

一些澳洲野犬作為寵物，因此

and after that they only survived in Tasmania.

牠們可能在生存活命上有優勢

Then, unfortunately,

我們所知道的是，當澳洲野犬被引進之後不久

the next sad part of the thylacine story is that Europeans arrived in 1788,

袋狼就從澳洲大陸上消失了

and they brought with them the things they valued,

此後只有塔思馬尼雅島有袋狼的蹤跡

and that included sheep.

然後，發生了袋狼生存史上另一件悲慘的事

They took one look at the thylacine in Tasmania,

就是歐洲人在1788年移入

and they thought, hang on, this is not going to work.

並帶來具經濟價值的事物，包括綿羊

That guy is going to eat all our sheep.

他們看了看島上的袋狼

That was not what happened, actually.

並且心想，等等，這行不通的

Wild dogs did eat a few of the sheep, but the thylacine got a bad rap.

袋狼將會吃掉所有的綿羊

But immediately, the government said, that's it, let's get rid of them,

但這件事其實從未發生過

and they paid people to slaughter every one that they saw.

野狗的確吃了一些綿羊 袋狼卻成了代罪羔羊

By the early 1930s,

但政府卻唐突的決定

3,000 to 4,000 thylacines had been murdered.

要除掉牠們，並獎賞

It was a disaster, and they were about to hit the wall.

那些屠殺袋狼的人

Have a look at this bit of film footage.

到1930、40年代，已有3000到4000隻

It makes me very sad because, while it's a fascinating animal,

被屠殺。這是一場災難

and it's amazing to think that we had the technology to film it

而牠們就快遇到瓶頸了

before it actually plunged off that cliff of extinction,

看看這部短片

we didn't, unfortunately, at this same time,

一部使我很感傷的影片

have a molecule of concern about the welfare for this species.

我們有這樣的科技去錄影

These are photos of the last surviving thylacine, Benjamin,

但在把牠推入絕種深淵之前

who was in the Beaumaris Zoo in Hobart.

很不幸地，我們沒有同時

To add insult to injury,

顧及這物種的存續

having swept this species nearly off the table,

這是一隻倖存的袋狼，Benjamin的照片

this animal, when it died of neglect --

在Hobart的Beaumaris動物園裡

The keepers didn't let it into the hutch on a cold night in Hobart.

雪上加霜的是，這隻袋狼竟死於疏於照料

It died of exposure, and in the morning, when they found the body of Benjamin,

使這物種的滅絕成為必然

they still cared so little for this animal that they threw the body in the dump.

管理員並未在Hobart一個寒冷的夜晚

Does it have to stay this way?

把牠安置在屋內，牠便因此死去

In 1990, I was in the Australian Museum.

當Benjamin的屍體在早上被發現時

I was fascinated by thylacines.

也並未引起太多關注

I've always been obsessed with these animals.

他們把牠的屍體丟到垃圾場了

And I was studying skulls,

事情真的必須這樣嗎？

trying to figure out their relationships to other sorts of animals,

1990年，我在澳洲的博物館

and I saw this jar,

被袋狼深深地吸引了，我總是被動物吸引

and here, in the jar, was a little girl thylacine pup,

而我研究頭骨，想了解

perhaps six months old.

袋狼跟其他物種之間的關係

The guy who had found it and killed the mother

而我看到這個罐子

had pickled the pup, and they pickled it in alcohol.

其中有一之母幼犬，大概六個月大

I'm a paleontologist, but I still knew alcohol was a DNA preservative.

殺了牠的人也殺了牠媽媽

But this was 1990, and I asked my geneticist friends,

並撿起裝進酒精中

couldn't we think about going into this pup

我是一個古生物學家，但我仍知到DNA保存法

and extracting DNA, if it's there,

但當時是1990年，而我問我遺傳學家的朋友

and then somewhere down the line in the future,

我們可否在這隻狗中

we'll use this DNA to bring the thylacine back?

萃取DNA，如果有的話

The geneticists laughed. But this was six years before Dolly.

在將來的某一天

Cloning was science fiction.

我們會利用DNA讓袋狼再現

It had not happened.

那位遺傳學家笑了。但這是在桃莉羊事件的六年前

But then suddenly cloning did happen.

生物複製仍然是很科幻的。他還未發生過。