ta的話題: 動物到底有多聰明呢

Who is smarter: a person or an ape? Well, it depends on the task. Consider Ayumu, a young male chimpanzee at Kyoto University who, in a 2007 study, put human memory to shame. Trained on a touch screen, Ayumu could recall a random series of nine numbers, from 1 to 9, and tap them in the right order, even though the numbers had been displayed for just a fraction of a second and then replaced with white squares.

人猿相比，誰更聰明？這個問題取決於比較的是什麼方面。比如說在日本京都大學(Kyoto University)2007年的一項研究中，一隻名爲“步”(Ayumu)的雄性小黑猩猩的記憶力就讓人類自愧不如。步通過一塊觸摸屏接受訓練，它能夠記得由一到九任意組合而成的一組共九個數字，並能以正確的順序在屏幕上把它們點出來，儘管這些數字只顯示了短短一瞬間便被白色的方格所取代。

I tried the task myself and could not keep track of more than five numbers -- and I was given much more time than the brainy ape. In the study, Ayumu outperformed a group of university students by a wide margin. The next year, he took on the British memory champion Ben Pridmore and emerged the 'chimpion.'

我自己也嘗試了這項測試，但我能回憶起的數字不超過五個──儘管我獲得的時間比那隻聰明的黑猩猩要長得多。在這項研究中，步的表現也比一羣京都大學的學生好出一大截。它在第二年還戰勝了來自英國的記憶測試冠軍──本?普里德莫爾(Ben Pridmore)，一舉成爲“猩猩冠軍”。

How do you give a chimp -- or an elephant or an octopus or a horse -- an IQ test? It may sound like the setup to a joke, but it is actually one of the thorniest questions facing science today. Over the past decade, researchers on animal cognition have come up with some ingenious solutions to the testing problem. Their findings have started to upend a view of humankind's unique place in the universe that dates back at least to ancient Greece.

你會如何對黑猩猩、大象、章魚、馬進行智商測試？這聽起來可能像是故意開玩笑，其實它是科學界當下面臨的最棘手的難題之一。過去十年間，研究動物認知能力的科研人員想出了一些有獨創性的解決方法。他們的發現開始逆轉至少可追溯至古希臘時期的有關人類在宇宙中的獨特位置的看法。

Aristotle's idea of the scala naturae, the ladder of nature, put all life-forms in rank order, from low to high, with humans closest to the angels. During the Enlightenment, the French philosopher Rene Descartes, a founder of modern science, declared that animals were soulless automatons. In the 20th century, the American psychologist B.F. Skinner and his followers took up the same theme, painting animals as little more than stimulus-response machines. Animals might be capable of learning, they argued, but surely not of thinking and feeling. The term'animal cognition' remained an oxymoron.

亞里士多德(Aristotle)的“自然階梯”(scalanaturae)理念將所有生命形式按從低到高的順序進行排列，其中人類的排序最接近天神。在啓蒙運動時期，作爲現代科學鼻祖之一的法國哲學家勒奈?笛卡爾(Rene Descartes)聲稱動物是沒有靈魂的機械物。到了20世紀，美國心理學家B.F.斯金納(B.F. Skinner)及其追隨者也是同樣的論調，將動物描繪得只比會應激做出反應的機器稍好一些。他們認爲動物或許具有學習能力，但是肯定不具備思考和感覺的能力。如此一來，“動物認知”一詞一直是個存有矛盾的詞。

A growing body of evidence shows, however, that we have grossly underestimated both the scope and the scale of animal intelligence. Can an octopus use tools? Do chimpanzees have a sense of fairness? Can birds guess what others know? Do rats feel empathy for their friends? Just a few decades ago we would have answered 'no' to all such questions. Now we're not so sure.

然而，越來越多的證據表明我們嚴重低估了動物智能的廣度和程度。章魚會運用工具嗎？黑猩猩具有公平感嗎？鳥兒能夠猜到其他鳥兒知道的事情嗎？老鼠對同類有同情心嗎？就在幾十年前，我們對所有這些問題的回答可能都是否定的，現在我們則沒有那麼確定了。

Experiments with animals have long been handicapped by our anthropocentric attitude: We often test them in ways that work fine with humans but not so well with other species. Scientists are now finally meeting animals on their own terms instead of treating them like furry (or feathery) humans, and this shift is fundamentally reshaping our understanding.

長期以來，動物實驗都受到我們以人類爲中心的態度的阻礙。我們常常以非常適合人類但不是那麼適合其他物種的方法對它們進行測試。現在，科學家們終於根據動物自身的情況來對待它們，不再把它們當作毛茸茸（或是長着羽毛）的人類，這個轉變從根本上重塑了我們對動物的看法。

Elephants are a perfect example. For years, scientists believed them incapable of using tools. At most, an elephant might pick up a stick to scratch its itchy behind. In earlier studies, the pachyderms were offered a long stick while food was placed outside their reach to see if they would use the stick to retrieve it. This setup worked well with primates, but elephants left the stick alone. From this, researchers concluded that the elephants didn't understand the problem. It occurred to no one that perhaps we, the investigators, didn't understand the elephants.

大象就是一個絕佳的例子。多年來，科學家們認爲大象不能使用工具，它可能最多隻會撿起根棍子撓撓發癢的後背。在早前的研究中，研究人員將食物放在大象夠不着的地方，然後給它們一根長棍子，看它們是否會用它取到食物。這個實驗的設計非常適合靈長類動物，但是大象卻無視棍子的存在。於是乎，研究人員由此得出結論稱大象不理解問題的要領。然而，沒有人意識到可能是我們這些科研人員不瞭解大象。

Think about the test from the animal's perspective. Unlike the primate hand, the elephant's grasping organ is also its nose. Elephants use their trunks not only to reach food but also to sniff and touch it. With their unparalleled sense of smell, the animals know exactly what they are going for. Vision is secondary.

從大象的角度想想這個實驗吧。與用手的靈長類動物不同，大象抓取物體的器官也是它的鼻子。它們不僅用鼻子抓取食物，也用它來聞嗅和觸碰食物。憑藉其無與倫比的嗅覺，大象確知自己拿的是什麼，視覺對它們來說是次要的。

But as soon as an elephant picks up a stick, its nasal passages are blocked. Even when the stick is close to the food, it impedes feeling and smelling. It is like sending a blindfolded child on an Easter egg hunt.

一旦撿起棍子，大象的鼻腔通道馬上就會被堵塞，所以即便棍子就在食物近旁，它也會阻礙大象的感覺和嗅覺。這就像矇住小孩的眼睛讓他去找復活節彩蛋一樣。

What sort of experiment, then, would do justice to the animal's special anatomy and abilities?

那麼，什麼類型的實驗對大象的特殊身體構造和能力來說是公平的呢？

On a recent visit to the National Zoo in Washington, I met with Preston Foerder and Diana Reiss of Hunter College, who showed me what Kandula, a young elephant bull, can do if the problem is presented differently. The scientists hung fruit high up above the enclosure, just out of Kandula's reach. The elephant was given several sticks and a sturdy square box.

在最近一次造訪位於華盛頓的國家動物園時，筆者與亨特學院(Hunter College)的普雷斯頓?福爾德(Preston Foerder)和黛安娜?瑞斯(Diana Reiss)見了面。他們向我展示，如果用不同的方式提出問題，一頭名爲“坎杜拉”(Kandula)的小公象都會做些什麼。他們將水果高高地掛在坎杜拉剛好夠不着的象舍的上方，然後給了它幾根棍子和一個堅固的方形箱子。

Kandula ignored the sticks but, after a while, began kicking the box with his foot. He kicked it many times in a straight line until it was right underneath the branch. He then stood on the box with his front legs, which enabled him to reach the food with his trunk. An elephant, it turns out, can use tools -- if they are the right ones.

坎杜拉沒有碰那些棍子，過了一會兒之後，它開始用腳踢箱子。它沿着直線方向踢了很多次箱子，直到把箱子踢到樹枝的正下方爲止，然後便把前腿搭在了箱子上，這樣一來它就能用鼻子夠着那些水果了。事實證明，大象也會使用工具──只要它們是適當的工具。

While Kandula munched his reward, the investigators explained how they had varied the setup, making life more difficult for the elephant. They had put the box in a different section of the yard, out of view, so that when Kandula looked up at the tempting food he would need to recall the solution and walk away from his goal to fetch the tool. Apart from a few large-brained species, such as humans, apes and dolphins, not many animals will do this, but Kandula did it without hesitation, fetching the box from great distances.

在坎杜拉大聲咀嚼戰利品的同時，研究人員說他們曾改變實驗的設計，加大了坎杜拉獲得食物的難度。他們把箱子放在院子中一個不在坎杜拉視線範圍內的區域，這樣一來當它看着充滿誘惑的食物時，它需要回憶起解決辦法，然後離開目標去取工具。除了人類、猿類和海豚等腦袋較大的物種之外，能夠做到這一點的動物並不多，但是坎杜拉毫不猶豫地採取行動，從很遠的距離取來了箱子。

Another failed experiment with elephants involved the mirror test -- a classic evaluation of whether an animal recognizes its own reflection. In the early going, scientists placed a mirror on the ground outside the elephant's cage, but the mirror was (unsurprisingly) much smaller than the largest of land animals. All that the elephant could possibly see was four legs behind two layers of bars (since the mirror doubled them). When the animal received a mark on its body visible only with the assistance of the mirror, it failed to notice or touch the mark. The verdict was that the species lacked self-awareness.

另一個與大象有關的失敗實驗是鏡像測試，這個經典的測試可評判動物是否認得出自己在鏡子中的形象。在早期的實驗中，科研人員在象籠外的地面上放了一面鏡子，但是這面鏡子（毫不意外地）比這個陸地上的最大動物要小得多。大象有可能看到的所有東西只是兩層欄杆（因爲鏡子的反射使欄杆變成了兩層）後的自己的四條腿。當它的身體被做上只能藉助鏡子才能看到的記號時，它沒能注意到或是觸碰那個記號，於是研究人員下結論稱大象缺乏自我意識。

But Joshua Plotnik of the Think Elephant International Foundation modified the test. He gave the elephants access to an 8-by-8-foot mirror and allowed them to feel it, smell it and look behind it. With this larger mirror, they fared much better. One Asian elephant recognized herself. Standing in front of the mirror, she repeatedly rubbed a white cross on her forehead, an action that she could only have performed by connecting her reflected image with her own body.

不過，非盈利組織Think Elephant International Foundation的喬舒亞?普羅特尼克(Joshua Plotnik)修正了這個實驗。他給大象提供的是一面長寬均爲八英尺（約合2.4米）的鏡子，允許它們去觸摸它、用鼻子聞它、從鏡子後看它。有了這面更大的鏡子，大象們的表現要好了很多。有一隻母亞洲象認出了自己，它站在鏡子前，不停地擦着額頭上一個白色的十字架記號，她只有把自己在鏡子中的形象與自己的身體聯繫起來纔可能做出這一舉動。

A similar experimental problem was behind the mistaken belief, prevalent until two decades ago, that our species has a unique system of facial recognition, since we are so much better at identifying faces than any other primate. Other primates had been tested, but they had been tested on human faces -- based on the assumption that ours are the easiest to tell apart.

這個認爲我們人類具有一個獨特的面部識別體系（因爲我們在面部識別方面比其他靈長類動物的表現要好得多）、直到20年前還很盛行的錯誤理念的背後也存在一個相同的實驗設計問題。儘管其他靈長類動物也接受了測試，但是它們的對象是人臉──這一設計的假設是我們人臉是最容易識別的。

When Lisa Parr, one of my co-workers at Emory University, tested chimpanzees on portraits of their own species, they excelled at it. Selecting portraits on a computer screen, they could even tell which juveniles were born to which females. Having been trained to detect similarities among images, the apes were shown a female's portrait and then given a choice between two other faces, one of which showed her offspring. They preferred the latter based purely on family resemblance since they did not know any of the depicted apes.

我在埃默裏大學(Emory University)的同事麗莎?帕爾(Lisa Parr)測試了黑猩猩對其同類的肖像的識別能力。它們在電腦屏幕上選擇肖像時甚至還能分辨出哪些小黑猩猩是哪些母猩猩的孩子。研究人員對這些黑猩猩進行了識別肖像相似處的訓練，然後向它們展示一幅母猩猩的肖像，隨後又讓它們在另外兩幅臉部肖像（其中一幅肖像中的猩猩爲母猩猩的孩子）之間做出選擇。它們是完全根據家族相似性選出母猩猩孩子的那幅像的，因爲它們並不認識畫像中的那幾只猩猩。

We also may need to rethink the physiology of intelligence. Take the octopus. In captivity, these animals recognize their caretakers and learn to open pill bottles protected by childproof caps -- a task with which many humans struggle. Their brains are indeed the largest among invertebrates, but the explanation for their extraordinary skills may lie elsewhere. It seems that these animals think, literally, outside the box of the brain.

我們或許還需重新思考有關智力的生理因素。以章魚爲例，它們在被人工飼養時認得飼養它們的人，並學會了打開帶防止兒童開啓的安全瓶蓋的藥瓶，這件事情很多人都難以辦到。章魚的腦袋在無脊椎動物中確實是最大的，但是能夠解釋它們這些非凡能力的或許另有原因。這種動物似乎的的確確是不經大腦思考的。

Octopuses have hundreds of suckers, each one equipped with its own ganglion with thousands of neurons. These 'mini-brains' are interconnected, making for a widely distributed nervous system. That is why a severed octopus arm may crawl on its own and even pick up food.

章魚有幾百個吸盤，每個吸盤都各有含數千條神經的神經節。這些“迷你大腦”互相連通，構成了一個分佈廣泛的神經系統，這也是章魚一條被砍斷的腕足可能會獨自爬行甚至是撿取食物的原因所在。

Similarly, when an octopus changes skin color in self-defense, such as by mimicking a poisonous sea snake, the decision may come not from central command but from the skin itself. A 2010 study found gene sequences in the skin of cuttlefish similar to those in the eye's retina. Could it be: an organism with a seeing skin and eight thinking arms?

同樣地，當章魚變化膚色進行自我防衛，比如擬態成有毒的海蛇時，這個決定或許並不是來自作爲指揮中心的大腦，而是來自皮膚本身。2010年的一項研究在烏賊的皮膚中發現了類似眼睛視網膜的基因序列。那麼章魚是否是一種皮膚具有視覺能力、八條腕足具有思維能力的生物體呢？

A note of caution, however: At times we also have overestimated the capacities of animals. About a century ago, a German horse named 'Kluger Hans' (Clever Hans) was thought to be capable of addition and subtraction. His owner would ask him the product of multiplying four by three, and Hans would happily tap his hoof 12 times. People were flabbergasted, and Hans became an international sensation.

不過，這裏還是要提醒一句，有時候我們也會高估動物的能力。大約在一個世紀前，德國一匹名爲“聰明漢斯”(Kluger Hans)的馬兒被人認爲能夠進行加減運算。其主人問它四乘以三等於多少時，它會歡快地輕踏12下蹄子。大家對此大吃一驚，而漢斯也成爲了引起世界性轟動的明星。

That is, until Oskar Pfungst, a psychologist, investigated the horse's abilities. Pfungst found that Hans was only successful if his owner knew the answer to the question and was visible to the horse. Apparently, the owner subtly shifted his position or straightened his back when Hans reached the correct number of taps. (The owner did so unknowingly, so there was no fraud involved.)

這種情況直到心理學家奧斯卡?芬斯特(Oskar Pfungst)對漢斯的智能進行調查之後才發生改變。芬斯特發現，只有在其主人知道問題的答案並且在其可見範圍之內時，漢斯才能答對題目。顯然，當漢斯輕踏蹄子的次數達到正確數字時，主人就會微微地改變姿勢或是直起背來。（其主人是在不知情的情況下這麼做的，因此也不涉及到欺詐。）

Some look at this historic revelation as a downgrading of Hans's intelligence, but I would argue that the horse was in fact very smart. His abilities at arithmetic may have been flawed, but his understanding of human body language was remarkable. And isn't that the skill a horse needs most?

有些人認爲，這個有歷史意義的真相的暴露表明漢斯的智力不是那麼高，不過筆者倒是認爲這匹馬實際上非常聰明。它的算數能力或許不盡如人意，但是它對人類身體語言的理解是非同尋常的。這難道不正是一匹馬最需要具備的能力嗎？

Awareness of the 'Clever Hans Effect, ' as it is now known, has greatly improved animal experimentation. Unfortunately, it is often ignored in comparable research with humans. Whereas every dog lab now tests the cognition of its animals while their human owners are blindfolded or asked to face away, young children are still presented with cognitive tasks while sitting on their mothers' laps. The assumption is that mothers are like furniture, but every mother wants her child to succeed, and nothing guarantees that her sighs, head turns and subtle changes in position don't serve as cues for the child.

對現今被人稱爲“聰明的漢斯效應”的意識促使動物實驗得到了極大改進。遺憾的是，這一點在類似的人類實驗中常常遭到忽視。現如今，儘管每個動物實驗室在測試動物的認知能力時都要把它們主人的眼睛蒙上或是要求他們把臉轉向別處，在對人類兒童進行認知測試時，兒童卻是坐在母親的腿上接受測試的。這一舉措的假設是母親所起的作用就像傢俱，但是每位母親都希望自己的孩子成功，沒法保證她的嘆息、轉頭動作或是細微的姿勢變化不會成爲對孩子的暗示。

This is especially relevant when we try to establish how smart apes are relative to children. To see how their cognitive skills compare, scientists present both species with identical problems, treating them exactly the same. At least this is the idea. But the children are held by their parents and talked to ('Watch this!' 'Where is the bunny?'), and they are dealing with members of their own kind. The apes, by contrast, sit behind bars, don't benefit from language or a nearby parent who knows the answers, and are facing members of a different species. The odds are massively stacked against the apes, but if they fail to perform like the children, the invariable conclusion is that they lack the mental capacities under investigation.

當我們嘗試去確認聰明的猿類與人類兒童相比有多聰明時，這一點就更是關係重大。爲了瞭解這二者的認知能力相比如何，科研人員以完全平等的方式對待他們，向他們提出一模一樣的問題──至少在科研人員看來是如此。然而，兒童往往有父母抱着或是有人對他們說話（比如說“看這個！”“小兔子在哪裏呢？”），而且他們與之打交道的是自己的同類。相比之下，猿類往往坐在欄杆後，沒有任何語言上的幫助，身旁也沒有知道答案的父母可提供幫助，而且它們面對的是另一個物種。因此，取勝形勢對猿類來說是極其不利的，但是如果它們未能像人類兒童表現的那麼好，結論始終都是它們缺乏研究人員所調查的心智能力。

A recent study, tracking the pupil movements of chimpanzees, found that they followed the gaze of members of their own species far better than that of humans. This simple finding has huge implications for tests in which chimpanzees need to pay attention to human experimenters. The species barrier they face may fully explain the difference in performance compared with children.

近期一項跟蹤黑猩猩瞳孔轉動的研究發現，黑猩猩對同類目光的追隨要比對人類目光的追隨好得多。這個簡單的發現對黑猩猩需要注意人類實驗人員的測試具有巨大的影響。它們所面臨的物種壁壘或許能夠完全解釋它們與人類兒童相比時表現的差距。

Underlying many of our mistaken beliefs about animal intelligence is the problem of negative evidence. If I walk through a forest in Georgia, where I live, and fail to see or hear the pileated woodpecker, am I permitted to conclude that the bird is absent? Of course not. We know how easily these splendid woodpeckers hop around tree trunks to stay out of sight. All I can say is that I lack evidence.

我們關於動物智能的許多錯誤觀念的深層原因在於反證這個問題。假如我在我所居住的佐治亞州穿過某個樹林時沒有看到北美黑啄木鳥或聽到它的聲音，我是不是就可以說這種鳥不存在呢？當然不能了。我們都知道這些美麗的啄木鳥能夠在樹幹之間輕鬆地跳來跳去躲開人的視線。我只能夠說我缺乏證據。

It is quite puzzling, therefore, why the field of animal cognition has such a long history of claims about the absence of capacities based on just a few strolls through the forest. Such conclusions contradict the famous dictum of experimental psychology according to which 'absence of evidence is not evidence of absence.'

因此，在動物認知領域中，人們僅僅在森林中溜達幾步便聲稱動物缺乏某些能力的歷史爲何如此之長令人相當費解。此類結論與實驗心理學中“找不到證據不代表證據不存在”的著名格言相悖。

Take the question of whether we are the only species to care about the well-being of others. It is well known that apes in the wild offer spontaneous assistance to each other, defending against leopards, say, or consoling distressed companions with tender embraces. But for decades, these observations were ignored, and more attention was paid to experiments according to which the apes were entirely selfish. They had been tested with an apparatus to see if one chimpanzee was willing to push food toward another. But perhaps the apes failed to understand the apparatus. When we instead used a simple choice between tokens they could exchange for food -- one kind of token rewarded only the chooser, the other kind rewarded both apes -- lo and behold, they preferred outcomes that rewarded both of them.

以我們人類是否是唯一一個關心別的同類好不好的物種這個問題爲例。衆所周知，猿類在野外會主動互相幫助，比如說防備豹子或是用溫柔的擁抱來安慰情緒低落的同伴。但是，數十年來這些現象都被忽視了，人們更關注的是那些認爲猿類完全是自私的實驗。研究人員在試驗中利用某種器材對黑猩猩進行實驗，查看它是否願意把食物推給另一隻黑猩猩。不過，這些黑猩猩不願這麼做也許只是因爲它們對那種器材沒有概念。當我們轉而採用簡單的選擇，要它們在兩個可以用來換取食物的標記中──其中一個標記只獎賞做出選擇的猩猩，另一個則同時獎賞兩隻猩猩──做出選擇，你瞧，它們會選擇同時獎勵它們二者的那個標記。

Such generosity, moreover, may not be restricted to apes. In a recent study, rats freed a trapped companion even when a container with chocolate had been put right next to it. Many rats first liberated the other, after which both rodents happily shared the treat.

此外，這種大度不僅僅體現在猿類身上。在最近一項研究中，即便身旁放了一個裝有巧克力的容器，老鼠還是會去解救受困的同伴。許多老鼠會先解救同伴，在這之後才一同高興地享用巧克力。

The one historical constant in my field is that each time a claim of human uniqueness bites the dust, other claims quickly take its place. Meanwhile, science keeps chipping away at the wall that separates us from the other animals. We have moved from viewing animals as instinct-driven stimulus-response machines to seeing them as sophisticated decision makers.

在我的研究領域，一個一成不變的歷史現象是，每當有表明人類獨特性的言論被推翻，其他相關言論就會迅速取而代之。與此同時，科學在不斷地慢慢消除將我們與其他動物隔離的圍 。我們已從把動物視爲受直覺推動的應激反應機械發展到把它們視爲可以做出決策的高級物種。

Aristotle's ladder of nature is not just being flattened; it is being transformed into a bush with many branches. This is no insult to human superiority. It is long-overdue recognition that intelligent life is not something for us to seek in the outer reaches of space but is abundant right here on earth, under our noses.

亞里士多德的自然階梯不是被簡單地夷平了，而是正在被轉變爲擁有許許多多分支的一叢灌木。這絕非是對人類優越性的褻瀆。智能生命並不是需要我們去外太空尋找的東西，它就大量存在於地球之上，存在於我們的眼皮底下，然而這個認識來得太遲了。