1、剑 4T1P1Tropical RainforestsAdults and children are frequently confronted with statements about the alarming rate of loss of tropical rainforests. For example, one graphic illustration to which children might readily relate is the estimate that rainforests are being destroyed at a rate equivalent to
2、one thousand football fields every forty minutes - about the duration of a normal classroom period. In the face of the frequent and often vivid media coverage, it is likely that children will have formed ideas about rainforests - what and where they are, why they are important, what endangers them -
3、 independent of any formal tuition. It is also possible that some of these ideas will be mistaken.Many studies have shown that children harbour misconceptions about pure curriculum science. These misconceptions do not remain isolated but become incorporated into a multifaceted, but organised, concep
4、tual framework, making it and the component ideas, some of which are erroneous,more robust but also accessible to modification. These ideas may be developed by children absorbing ideas through the popular media. Sometimes this information may be erroneous. It seems schools may not be providing an op
5、portunity for children to re-express their ideas and so have them tested and refined by teachers and their peers.Despite the extensive coverage in the popular media of the destruction of rainforests, little formal information is available about childrens ideas in this area. The aim of the present st
6、udy is to start to provide such information, to help teachers design their educational strategies to build upon correct ideas and to displace misconceptions and to plan programmes in environmental studies in their schools.The study surveys childrens scientific knowledge and attitudes to rainforests.
7、 Secondary school children were asked to complete a questionnaire containing five open-form questions. The most frequent responses to the first question were descriptions which are self-evident from the term “rainforest“. Some children described them as damp, wet or hot. The second question concerne
8、d the geographical location of rainforests. The commonest responses were continents or countries:Africa (given by 43% of children), South America (30%), Brazil (25%). Some children also gave more general locations, such as being near the Equator.Responses to question three concerned the importance o
9、f rainforests. The dominant idea, raised by 64% of the pupils, was that rainforests provide animals with habitats. Fewer students responded chat rainforests provide plant habitats, and even fewer mentioned the indigenous populations of rainforests. More girls (70%) than boys (60%) raised die idea of
10、 rainforest as animal habitats.Similarly, but at a lower level, more girls (13%) than boys (5%) said that rainforests provided human habitats. These observations are generally consistent with our previous studies of pupils views about the use and conservation of rainforests, in which girls were show
11、n to be more sympathetic to animals and expressed views which seem to place an intrinsic value on non-human animal life.The fourth question concerned the causes of the destruction of rainforests. Perhaps encouragingly, more than half of the pupils (59%) identified chat it is human activities which a
12、re destroying rainforests, some personalising the responsibility by the use of terms such as “we are“. About 18% of the pupils referred specifically to logging activity.One misconception, expressed by some 10% of the pupils, was chat acid rain is responsible for rainforest destruction; A similar pro
13、portion said chat pollution is destroying rainforests. Here, children are confusing rainforest destruction with damage to the forests of Western Europe by these factors. While two fifths of the students provided the information that the rainforests provide oxygen, in some cases this response also em
14、braced. The misconception that rainforest destruction would reduce atmospheric oxygen, making the atmosphere incompatible with human life on Earth.In answer to the final question about the importance of rainforest conservation, the majority of children simply said that we need rainforests to survive
15、. Only a few of the pupils (6%) mentioned that rainforest destruction may contribute to global warming. This is surprising considering the high level of media coverage on this issue. Some children expressed the idea that the conservation of rainforests is not important.The results of this study sugg
16、est that certain ideas predominate in the thinking of children about rainforests. Pupils responses indicate some misconceptions in basic scientific knowledge of rain forests ecosystems such as their ideas about rainforests as habitats for animals, plants and humans and the relationship between clima
17、tic change and destruction of rainforests.Pupils did not volunteer ideas that suggested that they appreciated the complexity of causes of rainforest destruction. In other words, they gave no indication of an appreciation of either the range of ways in which rainforests are important or the complex s
18、ocial, economic and political factors which drive the activities which are destroying the rainforests. One encouragement is that the results of similar studies about other environmental issues suggest that older children seem to acquire the ability to appreciate, value and evaluate conflicting views
19、. Environmental education offers an arena in which these skills can be developed, which is essential for these children as future decision-makers.无论大人还是孩子都经常会遇到这样的报道,那就是热带雨林正在以惊人的速度消失。打个比方,孩子们很容易就能理解这样一个图例,即平均每四十分钟,也就是一节课的时间内,世界上就会有相当于一千个足球场大小的热带雨林进到破坏。面对媒体频繁且生动的报道,也许不需要任何正规的教育,孩子们就能够形成一系列有关热带雨林的观点:
20、比如说雨林是什么,位置在哪里,为什么如此重要,又是什么在威胁它们等等。当然,这些观点也很有可能是错的。许多研究表明孩子们对于在学校里学到的科学知识心存误解。这些误解不是孤立存在的, 而是组成了一个尽管多层面却十分有条理的概念体系,这一点使得该体系本身及其所有的组成观点更加难以攻破,有些观点本身甚至就是错误的,但是也正是这样,它们反而更容易被改动。这些错误观点正是由于孩子们从大众煤体上吸收了信息而形成的。有时连这些信息本身都是错误的。学校似乎也没能够给们提供一个再度阐述自己观点的机会,因此老师及其他学生也不能帮助其检验及纠正这种错误观点。尽管媒体对于热带雨林所遭受的破坏做了大量的报道,何是有关孩
21、子相关观点的信息却少之又少。所以,目前这项研究的目的就是要给教师提供这样的信息来帮助他们设计自己的教学策略,以便帮助学生构筑正确的观点,置换他们的错误概念,并在学校中展开环保研究项目。该项研究调查了孩子有关热带雨林的科学知识以及态度。研究要求一些中学生填写一份包含了五个简答题的调查表。对于第一个问题.最常见的解答就来自“热带雨林”这一名称 所附带的不言自明的含义。有些孩子把雨林描述成一个又潮又湿或闷热的地方。第二个问题是关于雨林的地理位置的,大多数答案都提到了国名或洲名:百分之四十三的孩子写了非洲, 百分之三十写了美洲,还有百分之二十五的人认为热带雨林主要分布在巴西。有些孩子给出 了如“赤道附
22、近”这样更为宽泛的答案。第三道题目问及了热带雨林的重要性。百分之六十四的学生认为雨林为动物提供了栖身之所。较少的学生回答说雨林是植物的生长地。更少的学生提到了雨林中的土著居民。其中, 有百分之七十的女孩子认为雨林是动物的家,而男孩子中只有百分之六十的人执此观点。相似的是,有百分之十三的女生认为热带雨林为人类提供了居所,而男生中有此想法的人只占百分之五。这些观点与先前就学生对热带雨林的开发及保护状况所做的研究的结果基本一致,该结果表项女生更容易表现出对小动物的同情,其观点也更容易将内在价值观基于动物而非人类生命上。第四个问题问到了热带雨林遭到破坏的原因。值得庆幸的是,过半的学生(百分之五十九)
23、都认为是人类的行为导致了这一破坏,有人甚至用 “我们”这样的字眼将问题与自身联系起来。大概有百分之十八的学生将这一破坏归咎干滥砍滥伐。百分之十的学生错误地认为是酸雨导致了雨林的破坏,.还有百分之十的学生觉得污染才是罪魁祸首。看来学生们是将热带雨林所受的破坏与上述因素对西欧森林的毁坏混为一谈了。 百分之四十的学生认为热带雨林为人们提供了氧气,在某种程度上,这样的答案也包含着一个误解,那就是认为热带雨林的消失会减少大气中氧气的含量,最终导致地球上的大气不再适合人类呼吸。在被问及雨林保护的重要性时,大部分学生只是认为人类离开雨林就无法生存。只有寥寥百分之六的人提到热带雨林的消失会导致全球变暖。鉴于媒
24、体对这个问题长篇累牍的报道, 这样的结果真是有点出人意料。还有些学生认为保不保护雨林根本无关紧要。研究结果表明,在学生们对雨林的观点中,某些观点明显占上风。在有些问题上,比如说热带雨林是植物、动物及人类的栖息地以及天气变化与雨林破坏之间的关系等,学生们的回答又表明了他们在一些基本科学知识上的误区。学生们给出的答案并不能够表明他们了解热带雨林所遭受破坏的原因的复杂性。换言之,没有任何迹象表明他们了解热带雨林对人类来讲到底如何重要以及那些破坏行为背后所潜藏 的复杂社会、经济及政治因素。然而,值得欣慰的是,其他类似环保研究的结果表明,大孩子们已经具备了鉴赏、理解以及评价矛盾观点的能力。而环保教育正是
25、为这些能力的养成提供舞台,这一点对于孩子们成为未来的政策制定者是至关重要的。剑 4T1P2What Do Whales FeelSome of the senses that we and other terrestrial mammals take for granted are either reduced or absent in cetaceans or fail to function well in water. For example, it appears from their brain structure that toothed species are unable to
26、 smell. Baleen species, on the other hand, appear to have some related brain structures but it is not known whether these are functional. It has been speculated that, as the blowholes evolved and migrated to the top of the head, the neural pathways serving sense of smell may have been nearly all sac
27、rificed. Similarly, although at least some cetaceans have taste buds, the nerves serving these have degenerated or are rudimentary.The sense of touch has sometimes been described as weak too, but this view is probably mistaken. Trainers of captive dolphins and small whales often remark on their anim
28、als responsiveness to being touched or rubbed, and both captive and free ranging cetacean individuals of all species (particularly adults and calves, or members of the same subgroup) appear to make frequent contact. This contact may help to maintain order within a group, and stroking or touching are
29、 part of the courtship ritual in most species. The area around the blowhole is also particularly sensitive and captive animals often object strongly to being touched there. The sense of vision is developed to different degrees in different species. Baleen species studied at close quarters underwater
30、 specifically a grey whale calf in captivity for a year, and free-ranging right whales and humpback whales studied and filmed off Argentina and Hawaii have obviously tracked objects with vision underwater, and they can apparently see moderately well both in water and in air. However, the position of
31、 the eyes so restricts the field of vision in baleen whales that they probably do not have stereoscopic vision. On the other hand, the position of the eyes in most dolphins and porpoises suggests that they have stereoscopic vision forward and downward. Eye position in freshwater dolphins, which ofte
32、n swim on their side or upside down while feeding, suggests that what vision they have is stereoscopic forward and upward. By comparison, the bottlenose dolphin has extremely keen vision in water. Judging from the way it watches and tracks airborne flying fish, it can apparently see fairly well thro
33、ugh the airwater interface as well. And although preliminary experimental evidence suggests that their in-air vision is poor, the accuracy with which dolphins leap high to take small fish out of a trainers hand provides anecdotal evidence to the contrary. Such variation can no doubt be explained wit
34、h reference to the habitats in which individual species have developed. For example, vision is obviously more useful to species inhabiting clear open waters than to those living in turbid rivers and flooded plains. The South American boutu and Chinese beiji, for instance, appear to have very limited
35、 vision, and the Indian susus are blind, their eyes reduced to slits that probably allow them to sense only the direction and intensity of light. Although the senses of taste and smell appear to have deteriorated, and vision in water appears to be uncertain, such weaknesses are more than compensated
36、 for by cetaceans well-developed acoustic sense. Most species are highly vocal, although they vary in the range of sounds they produce, and many forage for food using echolocation. Large baleen whales primarily use the lower frequencies and are often limited in their repertoire. Notable exceptions a
37、re the nearly song-like choruses of bowhead whales in summer and the complex, haunting utterances of the humpback whales. Toothed species in general employ more of the frequency spectrum, and produce a wider variety of sounds, than baleen species (though the sperm whale apparently produces a monoton
38、ous series of high-energy clicks and little else). Some of the more complicated sounds are clearly communicative, although what role they may play in the social life and culture of cetaceans has been more the subject of wild speculation than of solid science.鲸鱼的感官对我们人类以及其他的陆地哺乳动物来说,有些感官是与生俱来的,然而对于鲸鱼
39、来讲, 这些功能要么已经衰退或彻底消失,要么就无法在水中正常发挥作用。比如说从齿鲸的大脑结构来看,它们是嗅不到气味的;而须鲸虽然有与嗅觉相关的脑部结构,可是我们却无法判断这些结构是否起作用。据推测,由于鲸鱼的气孔进化并最终移到了头部的正中所以掌管 嗅觉的神经纤维几乎全部不见了。同样,尽管有些鲸鱼也有味蕾,但这些味觉器官要么已经退化,要么就根本没有发育。有人认为鲸鱼的触觉也不发达,不过这个观点很可能是错误的。训练人工饲养海豚和小鲸鱼的人常常会评论他们的小动物对于触碰和抚摩的敏感度。而无论是人工饲养还是放养, 几乎所有种类的鲸鱼个体之间都会进行频繁的接触,特别是在成年鲸鱼和幼鲸之间或同一亚群的成员
40、之间。这种接触有助于维护同一种群内部的秩序,而且对大多数鲸鱼而言,抚摸和触碰也是求偶仪式的一部分。气孔周围的部分尤其敏感,一旦被触碰,人工饲养的鲸鱼就会有激烈的反应。不同种类的鲸鱼,视觉发达程度也各不相同。通过研究一只被人工饲养了一年的小灰鲸,以及通过对阿根廷和夏威夷沿海所放养的露脊鲸和座头鲸的研究及拍摄,人们发现在封闭水 域中的须鲸显然可以利用视觉来追踪水下的物体,而且它们无论在水中或空气中视力都相当好。但是眼睛的位置如此严重地限制了须鲸的视野,以致于它们可能不具备立体视觉。从另一方面来看,大多数海豚和江豚眼睛的位置表明它们是拥有向前及向下的立体视觉的。淡水海豚经常则游,或是在吃东西的时候肚
41、皮朝上游泳,这就表明眼睛的位置使它们拥 有向前及向上的立体视觉。相反的是,宽吻海豚在水中视力就很敏锐,而从它观察及追踪空 中飞鱼的方式来看,它在水天交界面的视力也相当好。尽管之前的实验证据表明,海豚在露 天环境中可能是睁眼瞎,然而,它们能够从水中跃起很髙,并且能够准确地吃到训练员手中的小鱼,这就有趣地证明了上述观点是错误的。当然,这些变异可以通过这些品种所生长的环境来解释。比如说,对于宽广清澈水域中的鲸鱼来说,视觉显然就有用的多;而对于那些住在混浊的河流或水淹的平原上的品种来说, 视力显然就没什么大用。比如,南美洲亚马逊河中的江豚以及中国的白鳍啄视力都相当有限, 而印度河中的江豚根本看不见东西
42、,它们的眼睛已经退化成了两条窄缝,除了感知上下方向和光的强度几乎没什么作用。尽管鲸鱼们的味觉和嗅觉严重衰退,在水中的视觉又不那么确定,然而这些缺陷完全可以被它们那高度发迖的听觉系统所弥补。尽管鲸鱼们音域不同,但是大多数鲸鱼都很会“唱 歌” ,而且还能用回声定位法来觅食。大个子须鲸只能用低频发声,除此之外就黔“鲸”计穷 了。当然也有些著名的例外:比如夏天里北极露脊鲸歌曲般的合唱,还有座头鲸那复杂的。 令人难以忘怀的低语。与须鲸相比,齿鲸们可以更多地利用频谱,发出多种声音,当然,抹香鲸只会发出一系列单调激烈的喀哒声。有些复杂的声音显然具有交流作用,然而想要搞淸 楚它们在鲸鱼的社会生活及文化中到底起
43、何作用,与其说是严谨科学研究的对象,不如说是丰富想象力的结果。剑 4T1P3Visual Symbols and the BlindPart 1From a number of recent studies, it has become 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 re
44、presentations. 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
45、 used, are a very recent invention in the history of illustration. Indeed, as art scholar David Kunzle notes, Wilhelm Busch, a trend-setting nineteenth-century cartoonist, used virtually no motion lines in his popular figures until about 1877.When I asked several other blind study subjects to draw a
46、 spinning wheel, one particularly clever rendition appeared repeatedly: several subjects showed the wheels 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 ver
47、y 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 discove
48、r whether there were differences in how the blind and the sighted interpreted lines of motion.To search out these answers, I created raised-line drawings of five different wheels, depicting spokes with lines that curved, bent, waved, dashed and extended beyond the perimeter of the wheel. I then aske
49、d 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 tha