How smart are dolphins? - Lori Marino

譯者: Wink Wong 審譯者: Seke Wei

In 1985, three researchers on a dolphin-studying expedition

1985年3名海豚研究員在出任務時

got a little bored.

覺得有點苦悶

To lighten things up, one pretended to be Poseidon

為了提高士氣，有人假裝成海神

by placing a seaweed garland on his head and then throwing it into the ocean.

頭戴草環，然後丟入海中

Moments later, a dolphin surfaced with the seaweed crowning her head.

一會兒，有隻頭帶草環的海豚，浮上水面

Sure, this could have been a coincidence,

當然，這或許是巧合

but it's also entirely possible that the dolphin was mimicking the scientist.

但是，也很有可能，海豚正在模仿科學家

That's because dolphins are one of the smartest animals species on Earth.

因為海豚是地球上最聰明動物之一

So exactly how smart are they?

那麼海豚究竟有多聰明？

Like whales and porpoises,

跟鲸魚和鼠海豚一樣

dolphins belong to the group of aquatic mammals

海豚屬於水生哺乳類動物

known as cetaceans who comprise 86 different species,

稱為鯨目動物，包含86類不同物種

and share a common link with ungulates, or hoofed animals.

跟有蹄類動物有近親關係

Originally land mammals,

本來是陸上的哺乳類動物

the first cetaceans entered the water about 55 million years ago

大約5千5百萬年前，鲸目動物開始進入水中生活

as large predators with sharp teeth.

由於長有利齒，是海中大型掠食者

Then, a shift in ocean temperatures about 35 million years ago

後來到了3千5百萬年前，海洋溫度變化

reduced the availability of prey.

獵物變得稀少

One group of cetaceans who survived this distruption,

在這種打擊下，只有一類鯨目動物生存下來

the odontocetes, wound up smaller with less sharp teeth,

就是齒鯨，牠們外形變小， 牙齒沒那麼鋒利

but also larger and more complex brains

但是腦部變大且複雜

that allowed for complex social relationships,

這樣可以讓牠們建立複雜的社交關係

as well as echolocation to navigate and communicate.

還有用回聲定位來導航和溝通

Jump ahead to the present,

跳回到現代

and modern dolphins' brains are so large that their encephalization quotient,

現代海豚的腦部很大，其腦化指數，也就是，

their brain size compared to the average for their body size,

和平均腦大小相比 (可由身體大小推估)， 實際腦所佔的比值

is second only to humans.

僅次於人類

Dolphins have evolved to survive

海豚為了生存而進化

through their ability to form complex social networks

牠們能夠組織複雜的社交網絡

that hunt, ward off rivals, and raise offspring together.

一起狩獵、避敵，甚至養育後代

For example, one group of Florida dolphins

例如，一羣佛羅里達州海豚

practices a sophisticated form of cooperation to hunt fish.

捕魚時就採用一種精密的合作方式

A dolphin designated as "the net-maker" kicks up mud

首先一隻海豚當＂下網者＂踢起塵土

while another gives the signal

這時另一隻海豚發出信號給其他海豚

for the other dolphins to simultaneously line up and catch the escaping fish.

同時聯合起來，捕捉外逃魚群

Achieving a goal like this requires deliberate planning and cooperation,

為了達到此目標， 這過程必須有周詳的計劃和合作

which, in turn, requires some form of intentional communication.

也需要某種形式的意圖溝通

Dolphins pass down their communication methods and other skills

海豚把這種溝通方法和其他技巧

from generation to generation.

一代一代傳授下去

Different dolphin populations exhibit variations in greetings,

不同的海豚族群在問候方式

hunting strategies, and other behaviors.

捕獵策略及其他行為上，各有不同

This sort of cultural transmission even extends to tool use.

這類文化傳遞甚至也包括工具的使用

One group of bottlenose dolphins off the Australian coast

鄰近澳洲海岸，有羣寛吻海豚

nicknamed The Dolphin Sponge Club,

綽號叫做海豚海綿俱樂部

has learned how to cover their rostrums with sponges when rooting in sharp corals,

牠們懂得用海綿包覆嘴部， 方便在鋒利的珊瑚礁中，以嘴拱土覓食

passing the knowledge from mother to daughter.

這種知識由母親傳授給女兒

Dolphins have even demonstrated language comprehension.

有實例證明海豚甚至可以理解語言

When taught a language based on whistles and hand gestures,

當人們敎導海豚利用 口哨聲和手部動作當溝通語言

they not only understood what the signals meant,

牠們不僅明白單獨信號表示的意義

but that their order had meaning:

還明白不同信號組合的順序所表示的意義:

the difference between bringing the ball to the hoop

例如: 牠們分得出帶球到環

and bringing the hoop to the ball.

和帶環到球的差異

So they were able to process two of the main elements of human language:

所以海豚能夠理解人類語言的兩要素：

symbols that stand for objects and actions,

一為代表物體和動作的符號

and syntax that governs how they are structured.

一為支配符號結構的語法

Dolphins are also one of the few species who pass the mirror test.

海豚也是能夠通過鏡子測試的少數動物之一

By recognizing themselves in mirrors, they indicate physical self-awareness,

牠們從鏡子中認出自己的樣子， 證明有認知自我身體的能力

and research shows they can recognize not just their bodies,

有研究顯示海豚不僅知道自己的身體

but also their own thoughts, a property called metacognition.

還知道自己的想法， 這種特質叫做元認知(meta-cognition)

In one study, dolphins comparing two sounds

有硏究發現海豚在比較兩種聲音時

could indicate a same, different, or uncertain response.

可以露出相同、不同，或不確定的反應

Just like humans,

正如人類一樣

they indicated uncertainty more often with difficult trials,

海豚遇到困難的測試時，常常露出不確定反應

suggesting they're aware of what they know,

表示海豚心中清楚自己知道什麼

and how confident they feel about that knowledge.

也清楚自己對那知道有多少信心

But some of the most amazing things about dolphins

此外，海豚還有一些令人很驚嘆的事情

are their senses of empathy, altruism, and attachment.

牠們有同理心、利他行為，和依戀之情

The habit of helping injured individuals extends across the species barrier

海豚救助傷者的習性已跨越了物種藩籬

as evidenced by the many accounts

從許多報導證明

of dolphins carrying humans to the surface to breathe.

海豚把人類帶上水面呼吸

And like us, dolphins mourn their dead.

海豚跟我們一樣，也為死去的同伴哀悼

When we consider all the evidence,

從種種的跡象看來

we may wonder why humans still hunt dolphins for meat,

我們也許覺得奇怪，人類為何還要捕殺海豚來吃

endanger them through fishing and pollution,

讓牠們遭到捕魚和污染的危害

or imprison them to perform tricks.

或把牠們關起來做花式表演

The ultimate question may not be whether dolphins are intelligent

而最終的問題也許不在於

and complex beings,

海豚是否為聰明而複雜的動物

but whether humans can empathize with them enough to keep them safe and free.

而在於人類對海豚是否有足夠的同理心， 願意讓牠們安全、自在的生活