on a journey of the underwater acoustic world

非常感謝。我要帶大家進入一段

of whales and dolphins.

鯨魚和海豚的

Since we are such a visual species,

水下聲音世界

it's hard for us to really understand this,

由於我們多依賴視覺，

so I'll use a mixture of figures and sounds

所以，要真正理解這些有點難度

and hope this can communicate it.

因此我會結合圖表與聲音 來說明

But let's also think, as a visual species,

希望這樣能把我想要表達的傳達給大家

what it's like when we go snorkeling or diving

但讓我們也思考一下，作為擁有視覺的物種，

and try to look underwater.

當我們浮潛或潛水時，

We really can't see very far.

看看水下的世界時，它是什麼樣的？

Our vision, which works so well in air,

其實我們看不了多遠

all of a sudden is very restricted and claustrophobic.

在地表上我們的視覺良好

And what marine mammals have evolved

但突然間 我們會在水下受到嚴重的限制與幽閉

over the last tens of millions of years

而海洋哺乳動物

is ways to depend on sound

經過了近數千萬年來的進化後，

to both explore their world

牠們依賴聲音

and also to stay in touch with one another.

探索周圍的世界

Dolphins and toothed whales use echolocation.

並與其他同類保持聯繫

They can produce loud clicks

海豚和齒鯨使用回聲定位

and listen for echoes from the sea floor in order to orient.

牠們能產生響亮的喀喇聲

They can listen for echoes from prey

並傾聽海底反射的回聲來定位

in order to decide where food is

牠們能通過獵物所反射的回聲

and to decide which one they want to eat.

來確定牠們的食物在哪里，

All marine mammals use sound for communication to stay in touch.

並決定要吃什麽

So the large baleen whales

所有海洋哺乳動物用聲音來保持相互聯繫

will produce long, beautiful songs,

於是大型鬚鯨

which are used in reproductive advertisement

能發出悠長美麗的歌聲，

for male and females, both to find one another

這種歌聲被雌鯨和雄鯨用於尋求伴侶，

and to select a mate.

幫助牠們找到同類，

And mother and young and closely bonded animals

並且選擇配偶

use calls to stay in touch with one another,

呼叫的聲音也被用於母子之間的聯繫，

so sound is really critical for their lives.

或者在聯繫緊密的動物之間保持聯繫

The first thing that got me interested in the sounds

因此，聲音在牠們的生活中是非常重要的

of these underwater animals,

第一個引起我對這些海底動物的

whose world was so foreign to me,

聲音興趣的是，

was evidence from captive dolphins

這對我來說是個陌生的世界

that captive dolphins could imitate human sounds.

從捕獲的海豚中 所發現的證據表示：

And I mentioned I'll use

牠們能模仿人類的聲音

some visual representations of sounds.

我說我會使用

Here's the first example.

一些聲音的視覺化圖像

This is a plot of frequency against time --

這是第一個例子

sort of like musical notation,

這是幅頻率對時間的圖表--

where the higher notes are up higher and the lower notes are lower,

有點像音符，

and time goes this way.

高處的標記表示頻率較高，低處的標記表示頻率較低，

This is a picture of a trainer's whistle,

時間朝這個方向流逝

a whistle a trainer will blow to tell a dolphin

這張圖表示教練的哨聲，

it's done the right thing and can come get a fish.

這哨聲是教練用來告訴海豚

It sounds sort of like "tweeeeeet." Like that.

做對了 就能得到一條魚。

This is a calf in captivity

它聽起來有點像 “tweeeeeet”。有點像這樣。

making an imitation

這是一隻人工飼養的小海豚

of that trainer's whistle.

模仿的

If you hummed this tune to your dog or cat

教練的哨聲

and it hummed it back to you,

現在如果你對這你的貓貓或狗狗哼這個曲子，

you ought to be pretty surprised.

而牠也對著你哼這曲子，

Very few nonhuman mammals

你應該會大吃一驚。

can imitate sounds.

很少有除人類之外的哺乳動物

It's really important for our music and our language.

能模仿聲音

So it's a puzzle: The few other mammal groups that do this,

這種能力對我們學習音樂和語言十分重要。

why do they do it?

因此這讓人迷惑：少有其他哺乳動物能做到這點，

A lot of my career has been devoted

為什麼牠們能做到這點？

to trying to understand

我職業生涯中花了很多時間

how these animals use their learning,

試圖弄明白

use the ability to change what you say

這些哺乳動物如何運用牠們的學習能力

based on what you hear

運用此一能力：

in their own communication systems.

基於所聽到的改變所說的。

So let's start with calls of a nonhuman primate.

這些都在牠們自己的溝通系統中

Many mammals have to produce contact calls

那麼讓我們從非人靈長類的叫聲開始

when, say, a mother and calf are apart.

許多哺乳動物會發出呼喚聲

This is an example of a call produced by squirrel monkeys

比如說，當母親和幼兒分開時

when they're isolated from another one.

這是一個例子：這是松鼠猴

And you can see, there's not much

與其他同類分開時所發出的叫聲。

variability in these calls.

如你們所見，在這些叫聲中

By contrast, the signature whistle

沒有多少變化

which dolphins use to stay in touch,

相對地，海豚用於

each individual here has a radically different call.

保持聯繫的哨聲，

They can use this ability to learn calls

每一隻海豚都有完全不同的聲調

in order to develop more complicated and more distinctive calls

牠們用這種能力來學習叫聲，

to identify individuals.

以便能發展出更複雜、更獨特的聲納

How about the setting in which animals need to use this call?

來辨別不同的個體

Well let's look at mothers and calves.

在怎樣的環境下 動物必須使用這種叫聲？

In normal life for mother and calf dolphin,

好，讓我們看看母親和幼海豚

they'll often drift apart or swim apart if Mom is chasing a fish,

在海豚媽媽和海豚幼兒平常的生活中，

and when they separate

如果海豚媽媽去抓魚，牠們經常因為漂移或是游泳而分開

they have to get back together again.

當牠們分開時

What this figure shows is the percentage of the separations

必須重新聚在一起

in which dolphins whistle,

這張圖顯示，牠們分開時

against the maximum distance.

海豚發出哨聲的百分比，

So when dolphins are separating by less than 20 meters,

與此相對的是最遠距離

less than half the time they need to use whistles.

因此，當海豚分隔少於 20 公尺時，

Most of the time they can just find each other

低於半數的情況下，牠們需要用到哨聲

just by swimming around.

大多數時間，牠們四處遊動

But all of the time when they separate by more than 100 meters,

就能找到對方

they need to use these individually distinctive whistles

然而一旦牠們分開超過100公尺，

to come back together again.

牠們就需要使用這些各自獨特的哨聲

Most of these distinctive signature whistles

再次聚在一塊。

are quite stereotyped and stable

多數這類帶有獨特個別特徵的哨聲

through the life of a dolphin.

在海豚的一生中

But there are some exceptions.

都是定型的、而且非常穩定

When a male dolphin leaves Mom,

但也有些例外

it will often join up with another male

當雄海豚離開海豚媽媽時，

and form an alliance, which may last for decades.

牠通常會聯合另一隻雄海豚

As these two animals form a social bond,

形成一個聯盟，這一聯盟可能會持續幾十年之久

their distinctive whistles actually converge

由於這兩隻動物形成了一條社會紐帶，

and become very similar.

牠們獨特的哨聲實際上會進行融合

This plot shows two members of a pair.

變得非常相似

As you can see at the top here,

這張圖顯示了組合中的兩個成員，

they share an up-sweep, like "woop, woop, woop."

正如你們於頂部所看到的，

They both have that kind of up-sweep.

牠們有著同樣的上升調，像“woop，woop，woop“

Whereas these members of a pair go "wo-ot, wo-ot, wo-ot."

牠們都有這樣的上升調

And what's happened is

然而，另一對成員擁有的上升調是”wo-ot, wo-ot, wo-ot“

they've used this learning process

這是由於：

to develop a new sign that identifies this new social group.

牠們運用此一學習過程

It's a very interesting way that they can

發展出識別新社會群體的新信號

form a new identifier

這是非常有趣的方式，牠們可以

for the new social group that they've had.

為新的社會群體

Let's now take a step back

形塑一個新的識別標誌

and see what this message can tell us

現在讓我們退後一步

about protecting dolphins

看看這訊息能告訴我們些什麼

from human disturbance.

關於保護海豚

Anybody looking at this picture

遠離人類干擾的資訊

will know this dolphin is surrounded,

任何看到這張圖片的人都知道

and clearly his behavior is being disrupted.

這隻海豚被包圍了，

This is a bad situation.

顯然牠的行為被打亂了。

But it turns out that when just a single boat

這是個糟糕的情況。

is approaching a group of dolphins

但事實表明，

at a couple hundred meters away,

當僅有一艘船在數百公尺外

the dolphins will start whistling,

靠近一群海豚時，

they'll change what they're doing, they'll have a more cohesive group,

這些海豚會開始發出哨聲，

wait for the boat to go by,

牠們會放棄正在做的事，聚集成更大的群體，

and then they'll get back to normal business.

等待這艘船駛過，

Well, in a place like Sarasota, Florida,

然後回復正常

the average interval between times

嗯，在一個佛羅里達州 Sarasota 的地方，

that a boat is passing within a hundred meters of a dolphin group

一艘船在百公尺之內

is six minutes.

駛過一群海豚的 平均間隔時間

So even in the situation that doesn't look as bad as this,

是六分鐘

it's still affecting the amount of time these animals have

因此，即使在看起來不像這麼糟糕的情形下，

to do their normal work.

在多數時刻，仍然會對這些動物的

And if we look at a very pristine environment like western Australia,

正常生活造成影響

Lars Bider has done work

讓我們看看像澳洲西部這樣一個非常原始的環境，

comparing dolphin behavior and distribution

Lars Bider 曾經

before there were dolphin-watching boats.

比較了賞海豚的遊船產生之前和之後，

When there was one boat, not much of an impact.

當地海豚的行為與分佈

And two boats: When the second boat was added,

當只有一艘船時，對牠們的影響不大

what happened was that some of the dolphins

兩艘船時，當第二艘船駛來時，

left the area completely.

有些海豚

Of the ones that stayed, their reproductive rate declined.

完全離開了這一區域

So it could have a negative impact on the whole population.

留下的那些海豚的繁殖率下降了

When we think of marine-protected areas for animals like dolphins,

因此，這可能對整個群體數量產生負面影響

this means that we have to be

當我們考慮動物比如海豚建立海洋保護區時，

quite conscious about activities that we thought were benign.

這意味著我們也要

We may need to regulate the intensity

非常慎重地考慮那些我們認為無礙的活動

of recreational boating and actual whale watching

我們也許需要控制

in order to prevent these kinds of problems.

遊船的密度，甚至賞鯨船的密度，

I'd also like to point out that sound

以防類似問題的發生

doesn't obey boundaries.

同樣，我想指出那些

So you can draw a line to try to protect an area,

沒有辦法設置防線的因素：聲音

but chemical pollution and noise pollution

你可以畫一條線，試圖保護一個區域，

will continue to move through the area.

但是化學污染和噪音污染

And I'd like to switch now from this local,

將不斷進入這一區域。

familiar, coastal environment

現在，我想從這種地方性的、

to a much broader world of the baleen whales and the open ocean.

為人熟知的沿海環境轉換至

This is a kind of map we've all been looking at.

鬚鯨的更廣闊的大海

The world is mostly blue.

我們經常看到這類地圖

But I'd also like to point out that the oceans

世界大部分是藍色的

are much more connected than we think.

但我還想指出的是，海洋之間的

Notice how few barriers there are to movement

聯繫地比我們所想像的更加緊密。

across all of the oceans compared to land.

請注意，相較於陸地而言，對海洋間的

To me, the most mind-bending example

運動的阻礙非常的少。

of the interconnectedness of the ocean

對我來說，最令人驚訝的海洋間

comes from an acoustic experiment

的相互聯繫的例子

where oceanographers

來自一個海洋學家所做的

took a ship to the southern Indian Ocean,

聲音實驗，

deployed an underwater loudspeaker

實驗中，海洋學家行駛至南印度洋，

and played back a sound.

放置一個水下揚聲器

That same sound

並不斷播放一個聲音。

traveled to the west, and could be heard in Bermuda,

同一段聲音

and traveled to the east, and could be heard in Monterey --

向西能傳播至百慕達群島，

the same sound.

向東能傳播至蒙特雷（Monterey）--

So we live in a world of satellite communication,

同一段聲音。

are used to global communication,

雖然我們生活在一個衛星通信的世界裏，

but it's still amazing to me.

早已習慣了全球間的溝通，

The ocean has properties

但我仍然感到驚訝

that allow low-frequency sound

海洋擁有了，基本上

to basically move globally.

能讓低頻聲音

The acoustic transit time for each of these paths is about three hours.

傳遍全球的特性。

It's nearly halfway around the globe.

聲音通過這些途徑中的每一條進行傳播所需的時間大約是三小時。

In the early '70s,

這幾乎穿越了半個地球。

Roger Payne and an ocean acoustician

在70年代早期，

published a theoretical paper

一名海洋聲學家，Roger Payne

pointing out that it was possible

曾發表過一篇學術論文，

that sound could transmit over these large areas,

論文中指出

but very few biologists believed it.

聲音能夠在大範圍內傳播，

It actually turns out, though,

但少有生物學家相信這點。

even though we've only known of long-range propagation for a few decades,

事實上，

the whales clearly have evolved,

雖然我們近幾十年來才對這種遠距離傳播有所瞭解，

over tens of millions of years,

而鯨魚顯然在數千萬年之前就已經

a way to exploit this amazing property of the ocean.

進行了進化，

So blue whales and fin whales

進化出一種方法來運用海洋的這種驚奇特性，

produce very low-frequency sounds

藍鯨和長鬚鯨

that can travel over very long ranges.

產生一種頻率非常低的聲音，

The top plot here shows

這種聲音能傳播很長的距離，

a complicated series of calls

上面這幅圖顯示

that are repeated by males.

雄鯨所重複的

They form songs, and they appear to play a role in reproduction,

一系列複雜的叫聲。

sort of like that of song birds.

這些叫聲形成歌聲，並且似乎能在繁殖中發揮作用，

Down below here, we see calls made by both males and females

有點類似鳥類的啼聲。

that also carry over very long ranges.

下面這幅圖，我們看到 無論是雄性還是雌性發出的叫聲

The biologists continued to be skeptical

都能傳播很遠的距離。

of the long-range communication issue

生物學家在70年代

well past the '70s,

持續地懷疑

until the end of the Cold War.

遠距離溝通的問題，

What happened was, during the Cold War,

直到冷戰結束為止。

the U.S. Navy had a system that was secret at the time,

冷戰期間，美國海軍

that they used to track Russian submarines.

開發出一套在當時處於保密的系統，

It had deep underwater microphones, or hydrophones,

這套系統能夠探測俄國潛艇，

cabled to shore,

它有一個深水麥克風，或者說，一個水下測音器，

all wired back to a central place that could listen

水下測音器用纜線連接至海岸，

to sounds over the whole North Atlantic.

所有纜線連接至一個中心，在那兒能監聽

And after the Berlin Wall fell, the Navy made these systems available

所有穿過整個北大西洋的聲音。

to whale bio-acousticians

在柏林牆倒塌之後，海軍允許鯨生物聲學家

to see what they could hear.

使用這些系統

This is a plot from Christopher Clark

看看他·們能聽到些什麼。

who tracked one individual blue whale

這幅圖來自Christopher Clark，

as it passed by Bermuda,

他在一條藍鯨

went down to the latitude of Miami and came back again.

經過百慕達時，跟蹤牠，

It was tracked for 43 days,

牠游至邁阿密同一緯度時，開始往回游，

swimming 1,700 kilometers,

牠被跟蹤了43天，

or more than 1,000 miles.

游了1700公里，

This shows us both that the calls

或者說超過1000英里。

are detectable over hundreds of miles

這告訴我們，這些叫聲

and that whales routinely swim hundreds of miles.

能在數百英里外被探測出來，

They're ocean-based and scale animals

這些鯨魚經常遊出數百英里遠。

who are communicating over much longer ranges

牠們是海洋大型動物，

than we had anticipated.

能夠以遠遠超出人們預期的距離

Unlike fins and blues, which

進行溝通。

disperse into the temperate and tropical oceans,

牠們與分佈在溫帶和熱帶的

the humpbacked whales congregate

鬚鯨和藍鯨不同，

in local traditional breeding grounds,

座頭鯨聚集於

so they can make a sound that's a little higher in frequency,

傳統繁殖地，

broader-band and more complicated.

因此牠們能發出頻率更高的聲音，

So you're listening to the complicated song

音域更寬且更複雜。

produced by humpbacks here.

你們現在聽到的是座頭鯨

Humpbacks, when they develop

發出的複雜歌聲。

the ability to sing this song,

當座頭鯨發展出

they're listening to other whales

這樣的歌聲能力時，

and modifying what they sing based on what they're hearing,