How does whale communication work? - David Gruber and Shane Gero

譯者: Lilian Chiu 審譯者: 麗玲 辛

In the mid-1800s,

1800 年代中期，

soon after American whaling ships began operating in the North Pacific,

美國捕鯨船開始在北太平洋 進行作業後不久，

an interesting trend emerged.

出現了一個有趣的趨勢。

Whalers saw a 58% drop in their successful strikes within just a few years.

捕鯨者發現捕鯨的成功次數

在幾年內就下降了 58%。

Sperm whales in the region had suddenly become much harder to kill.

該地區的抹香鯨突然變得很難捕殺。

Generally, when predators like orcas are nearby,

通常，當捕食性動物 如虎鯨在附近時，

sperm whales protect their most vulnerable

抹香鲸保護其弱者的方式

by forming defensive circles at the surface.

是在水面形成防禦圈。

But this behavior made them susceptible to whaling ships.

但這種行為讓牠們很容易 受到捕鯨船的攻擊。

It seems that sperm whales in the North Pacific

北太平洋的抹香鯨似乎

were somehow able to quickly adapt to this reality.

很快以某種方式適應這種現實。

Groups that likely hadn’t yet experienced human attacks

尚未受過人類攻擊的魚群

began escaping whaling boats on fast currents

開始會利用快速的洋流逃離捕鯨船，

instead of forming defensive circles.

而不是形成防禦圈。

And, based on what we’re starting to understand about sperm whales,

根據我們對抹香鯨逐漸增加的認識，

it seems possible they were actually broadcasting survival strategies

有可能牠們會傳播生存策略給彼此。

to one another.

Indeed, unbeknownst to whalers,

的確，捕鯨者不知道，

spermaceti, the material they killed for,

他們捕殺鯨魚，想取得的鯨蠟

is an essential part of the sperm whale’s sophisticated communication

是抹香鯨精密溝通不可少的一部分，

and echolocation system.

也用在回聲定位。

This waxy substance fills a cavity in the sperm whale’s head.

抹香鯨頭部的腔中 滿是這種蠟狀物質。

And their head is mostly comprised of an expanded nose

而牠們膨脹的鼻部 佔了頭部的很大比例，

that serves as a highly calibrated sonar system.

鼻部扮演的角色是精準的聲納系統。

Sperm whales generate some of the loudest biological noises on record,

抹香鯨所產生的生物噪音 是歷史記錄中最大的，

communicate copiously using an array of complex vocalization styles,

牠們用各種複雜的聲音風格， 做大量的溝通，

and have the largest brains on Earth.

且牠們的大腦是地球上最大的。

They spend most of their time searching the ocean's depths for prey.

牠們大部分的時間 都在海洋深處尋找獵物。

They can stay submerged for over an hour, and dive deeper than 1,200 meters,

牠們可以在水裡待超過一個小時，

且能下潛到至少一千兩百公尺深，

far beyond sunlight’s reach, where they’re guided by sound.

陽光根本照射不到這麼深， 所以要靠聲音來引導。

The loudest noise recorded underwater is around 270 decibels.

根據記錄，水中最大聲的 噪音約為兩百七十分貝。

Sperm whale-generated sounds can reach 230.

抹香鯨產生的聲音 可高達兩百三十分貝。

And they frequently fix their high-intensity echolocation clicks

牠們經常用高強度的 回聲定位聲來鎖定

on squid.

烏賊。

Some of the air they inhale through their blowhole is routed into their lungs,

牠們從鯨孔吸入的空氣， 有部分會進入肺部。

while the rest enters a complex, sound-producing system.

其餘空氣則進入到 一個複雜的聲音產生系統。

There, air is funneled through lip-like appendages at the front of their heads.

在那裡，空氣會通過牠們頭部 前方類似嘴脣的附屬器官。

This generates a sound that travels backwards through their spermaceti organ,

這會產生一種聲音，透過 牠們的鯨蠟器官反向傳送，

bounces off an air sac, then traverses another waxy organ,

聲音被氣囊反彈，接著 再通過另一個蠟質器官，

which amplifies and directs the sound.

這個器官會放大聲音 並引導聲音的方向。

The click exits the sperm whale’s head a powerful, focused beam.

定位聲離開抹香鯨頭部時， 是強力且集中的聲音束。

It’s suspected that the returning vibrations

有人認為回傳的震動

are received by the whale’s lower jaw and directed into the ears.

是由鯨魚的下顎接收，再導入耳部。

Then, their brain’s expanded auditory processing region

接著，牠們腦中 聲音處理的廣大區域

analyzes the quality of the echoes to map their surroundings in the darkness.

分析回聲的特性， 勘測出黑暗中的周圍環境。

With this mechanism, sperm whales can locate squid 300 meters away.

靠這種機制，抹香鯨可以得知 三百公尺外的烏賊所在。

Scientists think squid don’t hear these high-frequency clicks—

科學家認為烏賊聽不到 這些高頻的定位聲——

even as they turn into rapid buzzes and creaks as the whale closes in.

即使隨著鯨魚靠近，定位聲 會變成嗡嗡聲和吱吱聲。

Sperm whales can eat more than a ton of squid every day.

每天，抹香鯨可以吃掉 至少一公噸的烏賊。

Their stomachs and feces are usually full of indigestible squid beaks,

牠們的胃裡和糞便中通常 滿是無法消化的烏賊嘴，

and their skin often scarred by squid tentacles.

牠們的皮膚上常常有 烏賊觸手留下的疤痕。

When they're not hunting, however,

但，不獵食時，

sperm whales use an entirely different vocal repertoire.

抹香鯨用的聲音曲目則完全不同。

Mature males make clang noises,

成熟的雄性鯨魚會發出叮叮聲，

which scientists suspect play a role in mating.

科學家認為可能和交配有關。

And most other sperm whales live in social family groups.

大部分其他的抹香鯨都生活在 社會型家庭群體中。

Though their communication might get interrupted when predators are near

雖然牠們的溝通有時可能會被 打斷，如捕食性動物靠近時，

or human-generated noises dominate,

或人類產生的聲音大到 壓過其他聲音時，

they generally chatter at length at the water’s surface.

但牠們通常會在海面上 長時間喋喋不休。

Sperm whales do this using patterned click sequences akin to Morse code,

抹香鯨聊天的方式是用 有特定模式的定位聲序列，

類似摩斯電碼，

called codas,

稱為「密碼曲」，

which are thought to function as social identity markers.

一般認為它具有 社會身分標誌的功能。

Researchers have identified dozens of distinct types of codas,

研究者已經辨識出了 數十種不同型的密碼曲，

according to patterns in the numbers of clicks used and their rhythm and tempo.

辨識參考的模式包括牠們用了 幾個定位聲、其節奏和速度。

Some codas are more ubiquitous,

有些密碼曲比較普遍，

while others vary greatly according to family groups and individuals.

其他密碼曲則會因為家庭群體 和個體而有很大的不同。

All families in a given region

在一個區域內的家庭，

that consistently use some of the same characteristic coda patterns

凡是持續使用某些 相同特徵的密碼曲模式，

share a dialect and belong to the same vocal clan.

就算是使用共同的方言， 且隸屬相同的聲音族群。

Each sperm whale calf goes through a multi-year period of babbling,

每隻小抹香鯨都要經過 數年的牙牙學語期，

where they experiment with different sounds

這段期間，牠們會試驗不同的聲音，

before becoming fluent in their clan’s coda dialect.

之後牠們才能流利地使用 所屬族群的密碼曲方言。

How and what exactly sperm whales communicate to each other

抹香鯨究竟如何溝通、講什麼內容，

is currently unknown,

目前都是未知，

but there are indications that the information can be sophisticated.

但有跡象顯示，牠們 傳遞的資訊可能很複雜。

Biologists, roboticists, linguists, cryptographers,

生物學家、機器人學家、 語言學家、密碼學家，

and artificial intelligence experts

以及人工智慧專家

are collaborating to monitor and analyze sperm whale vocalizations.

正在合作監聽和分析抹香鯨的發聲。

The aim is to finally decipher what they're saying.

最終目標是希望 能聽懂牠們在說什麼。