【文章內容簡介】 向下的立體視覺的。淡水海豚經常則游，或是在吃東西的時候肚皮朝上游泳，這就表明眼睛的位置使它們擁 有向前及向上的立體視覺。相反的是，寬吻海豚在水中視力就很敏銳，而從它觀察及追蹤空 中飛魚的方式來看，它在水天交界面的視力也相當好。盡管之前的實驗證據(jù)表明，海豚在露 天環(huán)境中可能是睜眼瞎，然而，它們能夠從水中躍起很髙，并且能夠準確地吃到訓練員手中的小魚，這就有趣地證明了上述觀點是錯誤的。當然，這些變異可以通過這些品種所生長的環(huán)境來解釋。比如說，對于寬廣清澈水域中的鯨魚來說，視覺顯然就有用的多；而對于那些住在混濁的河流或水淹的平原上的品種來說， 視力顯然就沒什么大用。比如，南美洲亞馬遜河中的江豚以及中國的白鰭啄視力都相當有限， 而印度河中的江豚根本看不見東西，它們的眼睛已經退化成了兩條窄縫，除了感知上下方向和光的強度幾乎沒什么作用。盡管鯨魚們的味覺和嗅覺嚴重衰退，在水中的視覺又不那么確定，然而這些缺陷完全可以被它們那高度發(fā)迖的聽覺系統(tǒng)所彌補。盡管鯨魚們音域不同，但是大多數(shù)鯨魚都很會“唱 歌”，而且還能用回聲定位法來覓食。大個子須鯨只能用低頻發(fā)聲，除此之外就黔“鯨”計窮 了。當然也有些著名的例外：比如夏天里北極露脊鯨歌曲般的合唱，還有座頭鯨那復雜的。 令人難以忘懷的低語。與須鯨相比，齒鯨們可以更多地利用頻譜，發(fā)出多種聲音，當然，抹香鯨只會發(fā)出一系列單調激烈的喀噠聲。有些復雜的聲音顯然具有交流作用，然而想要搞淸 楚它們在鯨魚的社會生活及文化中到底起何作用，與其說是嚴謹科學研究的對象，不如說是豐富想象力的結果。劍4T1P3Visual Symbols and the BlindPart 1From a number of recent studies, it has bee clear that blind people can appreciate the use of outlines and perspectives to describe the arrangement of objects and other surfaces in space. But pictures are more than literal representations. This fact was drawn to my attention dramatically when a blind woman in one of my investigations decided on her own initiative to draw a wheel as it was spinning. To show this motion, she traced a curve inside the circle (Fig. 1). I was taken aback. Lines of motion, such as the one she used, are a very recent invention in the history of illustration. Indeed, as art scholar David Kunzle notes, Wilhelm Busch, a trendsetting nineteenthcentury cartoonist, used virtually no motion lines in his popular figures until about 1877.When I asked several other blind study subjects to draw a spinning wheel, one particularly clever rendition appeared repeatedly: several subjects showed the wheel’s spokes as curved lines. When asked about these curves, they all described them as metaphorical ways of suggesting motion. Majority rule would argue that this device somehow indicated motion very well. But was it a better indicator than, say, broken or wavy lines – or any other kind of line, for that matter? The answer was not clear. So I decided to test whether various lines of motion were apt ways of showing movement or if they were merely idiosyncratic marks. Moreover, I wanted to discover whether there were differences in how the blind and the sighted interpreted lines of motion.To search out these answers, I created raisedline drawings of five different wheels, depicting spokes with lines that curved, bent, waved, dashed and extended beyond the perimeter of the wheel. I then asked eighteen blind volunteers to feel the wheels and assign one of the following motions to each wheel: wobbling, spinning fast, spinning steadily, jerking or braking. My control group consisted of eighteen sighted undergraduates from the University of Toronto.All but one of the blind subjects assigned distinctive motions to each wheel. Most guessed that the curved spokes indicated that the wheel was spinning steadily。 the wavy spokes, they thought, suggested that the wheel was wobbling。 and the bent spokes were taken as a sign that the wheel was jerking. Subjects assumed that spokes extending beyond the wheel’s perimeter signified that the wheel had its brakes on and that dashed spokes indicated the wheel was spinning quickly.In addition, the favoured description for the sighted was the favoured description for the blind in every instance. What is more, the consensus among the sighted was barely higher than that among the blind. Because motion devices are unfamiliar to the blind, the task I gave them involved some problem solving. Evidently, however, the blind not only figured out meanings for each line of motion, but as a group they generally came up with the same meaning at least as frequently as did sighted subjects.Part 2We have found that the blind understand other kinds of visual metaphors as well. One blind woman drew a picture of a child inside a heart – choosing that symbol, she said, to show that love surrounded the child. With Chang Hong Liu, a doctoral student from China, I have begun exploring how well blind people understand the symbolism behind shapes such as hearts that do not directly represent their meaning.We gave a list of twenty pairs of words to sighted subjects and asked them to pick from each pair the term that best related to a circle and the term that best related to a square. For example, we asked: What goes with soft? A circle or a square? Which shape goes with hard?All our subjects deemed the circle soft and the square hard. A full 94% ascribed happy to the circle, instead of sad. But other pairs revealed less agreement: 79% matched fast to slow and weak to strong, respectively. And only 51% linked deep to circle and shallow to square. (See Fig. 2.) When we tested four totally blind volunteers using the same list, we found that their choices closely resembled those made by the sighted subjects. One man, who had been blind since birth, scored extremely well. He made only one match differing from the consensus, assigning ‘far’ to square and ‘near’ to circle. In fact, only a small majority of sighted subjects – 53% – had paired far and near to the opposite partners. Thus, we concluded that the blind interpret abstract shapes as sighted people do.盲人與視覺符號最近的幾次研究表明，盲人可以理解用輪廓線和透視法來描述物體排列及空間平面的方法。但是，圖畫不只是表面意思的體現(xiàn)。在研究中，一名盲人女性自發(fā)地畫出了一個轉動的車輪，這就引起了我對上述事實的極大關注。為了展示這樣一個動作，她在圓圈中畫了一條曲線。我大吃一驚。像她所使用的這種運動線是插圖史上最近的發(fā)明。實際上，正如藝術學 者David Kunzle指出的那樣，Wilhelm Busch,—名引領潮流的19世紀卡通畫家，直到1877 年才開始在其最流行的人物身上使用運動線。當我要其他接受研究的盲人對象畫出轉動中的車輪時，一種特別聰明的畫法反復出現(xiàn)了：幾個人把車條畫成了曲線。當被問到為什么要用曲線的時候，他們都說這是喑示運動的一種帶有隱喻意味的方法。多數(shù)原則會認為從某種角度來講，這個圖案充分地表示了運動。但是就此而言，曲線是不是比，比如說虛線，波浪線或者其他任何一種線條，更能說明問題呢？答 案是不確定的。所以我決定測試一下，不同的運動線是否就是表現(xiàn)運動的恰當方式，而或它們只是一些特殊的符號而已。進一步而言，我還想找出盲人和普通人在詮釋運動線時的不同之處。為了找出答案，我用凸起線條做出了五幅有關輪子的畫，車條被畫成大曲線，小曲線，波浪 線，虛線以及超出車輪的直線。然后，我讓18名盲人志愿者撫摩這些輪子，并且將它們分別 與下列運動中的一個搭配：不穩(wěn)定地轉動1飛速轉動，穩(wěn)定地轉動，顛簸和剎車。參照組則是由來自于多倫多大學的18名普通大學生組成的。除了一個人，其他所有的盲人都將具體的動作與車輪搭配了起來。大多數(shù)人猜測被畫成大曲 線的車條表示車輪正在穩(wěn)定地轉動；而他們認為波浪線車條表示車輪在不穩(wěn)定地轉動，小曲 線則被認為是車輪正在顛簸的象征。受試者推測，超出車輪邊緣的車條代表車輪正處在剎車狀態(tài)，而虛線車條則說明車輪正在飛快地旋轉。另外，在每種情況下，普通