2022-06-27 14:10:26 来源:中国教育在线
一、Whales and Dolphins听力原文:
Good afternoon everyone.
Well,with some of you about to go out on field work it's timely that in this afternoon's session.
I'll be sharing some ideas about the reasons why groups of whales and dolphins sometimes swim ashore from the sea right onto the beach and,most often,die in what are known as'mass strandings'.
Unfortunately,this type of event is a frequent occurrence in some of the locations that you'll be travelling to,where sometimes the tide goes out suddenly,confusing the animals.
However,there are many other theories about the causes of mass strandings.
The first is that the behaviour is linked to parasites.
It's often found that stranded animals were infested with large numbers of parasites.
For instance,a type of worm is commonly found in the ears of dead whales.
Since marine animals rely heavily on their hearing to navigate,this type of infestation has the potential to be very harmful.
Another theory is related to toxins,or poisons.
These have also been found to contribute to the death of many marine animals.
Many toxins,as I'm sure you're aware,originate from plants,or animals.
The whale ingests these toxins in its normal feeding behaviour but whether these poisons directly or indirectly lead to stranding and death,seems to depend upon the toxin involved.
In 1988,for example,fourteen humpback whales examined after stranding along the beaches of Cape Cod were found to have been poisoned after eating tuna that contained saxitoxin,the same toxin that can be fatal in humans.
Alternatively,it has also been suggested that some animals strand accidentally by following their prey ashore in the confusion of the chase.
In 1995 David Thurston monitored pilot whales that beached after following squid ashore.
However,this idea does not seem to hold true for the majority of mass strandings because examination of the animals stomach contents reveal that most had not been feeding as they stranded.
There are also some new theories which link strandings to humans.
A growing concern is that loud noises in the ocean cause strandings.
Noises such as those caused by military exercises are of particular concern and have been pinpointed as the cause of some strandings of late.
One of these,a mass stranding of whales in 2000 in the Bahamas coincided closely with experiments using a new submarine detection system.
There were several factors that made this stranding stand out as different from previous strandings.
This led researchers to look for a new cause.
For one,all the stranded animals were healthy.
In addition,the animals were spread out along 38 kilometres of coast,whereas it's more common for the animals to be found in a group when mass strandings occur.
A final theory is related to group behaviour,and suggests that sea mammals cannot distinguish between sick and healthy leaders and will follow sick leaders,even to an inevitable death.
This is a particularly interesting theory since the whales that are thought to be most social-the toothed whales–are the group that strand the most frequently.
The theory is also supported by evidence from a dolphin stranding in 1994.
Examination of the dead animals revealed that apart from the leader,all the others had been healthy at the time of their death.
Without one consistent theory however it is very hard for us to do anything about this phenomenon except to assist animals where and when we can.
Stranding networks have been established around the world to aid in rescuing animals and collecting samples from those that could not be helped.
I recommend John Conner's Marine Mammals Ashore as an excellent starting point if you're interested in finding out more about these networks,or establishing one yourself.
二、Whales and Dolphins听力中文翻译:
大家下午好。
好吧,由于你们中的一些人将要进行实地工作,今天下午的会议很及时。
我将分享一些关于鲸鱼和海豚群体有时从海上游上岸到海滩的原因的想法,最常见的是死于所谓的“大规模搁浅”。
不幸的是,这类事件在你将要去的一些地方经常发生,有时潮水突然退去,让动物感到困惑。
然而,关于大规模搁浅的原因还有许多其他理论。
首先,这种行为与寄生虫有关。
人们经常发现搁浅的动物感染了大量寄生虫。
例如,一种蠕虫通常在死鲸的耳朵中发现。
由于海洋动物在很大程度上依赖听觉来导航,这种类型的感染可能非常有害。
另一种理论与毒素有关。
这些也被发现导致许多海洋动物死亡。
我相信你也知道,许多毒素来自植物或动物。
鲸鱼在正常的进食行为中摄入这些毒素,但这些毒素是否直接或间接导致搁浅和死亡,似乎取决于所涉及的毒素。
例如,1988年,14头在科德角海滩搁浅后接受检查的座头鲸被发现在食用含有萨克森毒素的金枪鱼后中毒,这种毒素可能对人类致命。
另一方面,也有人认为,一些动物在追逐的混乱中跟随猎物上岸,从而意外搁浅。
1995年,大卫·瑟斯顿(DavidThurston)监测了跟踪鱿鱼上岸后搁浅的领航鲸。
然而,这一观点似乎并不适用于大多数大规模搁浅,因为对动物胃内容物的检查显示,大多数动物搁浅时没有进食。
还有一些新的理论将搁浅与人类联系起来。
人们越来越担心海洋中的噪音会导致搁浅。
诸如军事演习引起的噪音尤其令人担忧,并被确定为最近一些搁浅的原因。
其中之一是2000年在巴哈马发生的鲸鱼大规模搁浅事件,与使用新的潜艇探测系统进行的实验非常吻合。
有几个因素使这次绞合与众不同,与以前的绞合不同。
这促使研究人员寻找新的原因。
首先,所有搁浅的动物都很健康。
此外,这些动物分布在38公里的海岸线上,而在发生大规模搁浅时,更常见的是成群结队的动物。
最后一个理论与群体行为有关,它认为海洋哺乳动物无法区分生病的领导者和健康的领导者,会追随生病的领导者,甚至会导致不可避免的死亡。
这是一个特别有趣的理论,因为被认为是最具社会性的鲸鱼——齿鲸——是最常搁浅的群体。
这一理论也得到了1994年海豚搁浅的证据的支持。
对死亡动物的检查显示,除了首领之外,所有其他动物在死亡时都是健康的。
然而,如果没有一个一致的理论,我们很难对这一现象采取任何行动,除非我们能够在何时何地帮助动物。
世界各地已经建立了搁浅网络,以帮助营救动物,并从那些无法帮助的动物身上采集样本。
如果你有兴趣了解更多关于这些网络的信息,或者自己建立一个网络,我推荐约翰·康纳的《岸上海洋哺乳动物》作为一个很好的起点。
三、Whales and Dolphins听力问题:
Question 31-40
Complete the notes below.
Write NO MORE THAN TWO WORDS for each answer.Mass Strandings of Whales and Dolphins
Mass strandings:situations where groups of whales,dolphins,etc.swim onto the beach and die
Common in areas where the can change quickly
Several other theories:
Parasites
e.g.some parasites can affect marine animals',which they depend on for navigation
Toxins
Poisons from or are commonly consumed by whales
e.g.Cape Cod(1988)-whales were killed by saxitoxin
Accidental Strandings
Animals may follow prey ashore,e.g.Thurston(1995)
Unlikely because the majority of animals were not when they stranded
Human Activity
from military tests are linked to some recent strandings
The Bahamas(2000)stranding was unusual because the whales
•were all
•were not in a
Group Behaviour
•More strandings in the most species of whales
•1994 dolphin stranding-only the was ill
Further Reading
Marine Mammals Ashore(Connor)-gives information about stranding
四、Whales and Dolphins听力答案:
31.tide/tides
32.hearing/ear/ears
33.plants;animals;fish;fishes;
34.feeding
35.noise/noises
36.healthy
37.group
38.social
39.leader
40.network/networks
五、Whales and Dolphins听力答案解析
31.tide利用定位词where考生可听到the tide goes out suddenly。goes out suddenly对应题干中的change quickly,goes out suddenly的主语便是答案。
注意剑桥答案还给了tides,但是建议考生考试时听见什么写什么,不要随意更改名词的单复数。
32.hearing考生听到有关题干定位词parasites部分的内容时,会听到Since marine animals rely heavily on their hearing to navigate...。rely on对应题干中的depend on,on后面的名词即为答案。
注意hearing与ear(s)有关,此外,录音中也出现了...commonly found in the ears of dead whales.的表达,因此答案也可以是ear(s)。
33.plants,animals利用题干中的poisons定位,考生可以听到Many toxins,as I’m sure you’re aware,originate from plants,or animals.。originate from对应题干中的from,所以答案是plants,animals。
注意答案顺序可以互换,另外,剑桥答案还给出了fish或fishes,建议考生不要这样写。
34.feeding利用题干中的Thurston定位。考生在听到majority of mass strandings之后,可以听到...most had not been feeding as they stranded.。had not been和as对应题干中的were not和when,所以答案是feeding。
35.noises利用题干中的military定位,考生可以听到Noises such as those caused by military exercises...cause of some strandings of late.,caused by对应题干中的from,cause of对应题干中的are linked to,所以可以确定答案是noises。
注意剑桥答案还给了noise,但是如果这样填,就会与题目中的谓语are不一致,所以请考生特别注意主谓形式的一致性。
36.healthy考生可以利用题干中的定位词the Bahamas(2000)重点听与其相关的内容,在介绍这部分内容时speaker指出了两方面的原因,For one,all the stranded animals were healthy.In addition...strandings occur.,据此可以确定答案是healthy。
37.group常规解题方法同第36题,此外,考生在听In addition...strandings occur.这句话时要特别注意,speaker提到了比较common的方式是found in a group,此表达对应了题干中的unusual的方式是not in a group,因此答案为group。
38.social考生可利用题干中同时出现的比较级和最高级进行定位。在听到interesting theory之后,考生可以听到...whales that are thought to be most social...strand the most frequently.,由此可以确定答案是social。
39.leader利用特殊时间词1994定位,考生可以听到...apart from the leader,all the others had been healthy...。apart from对应题干中的only,由此可知答案为leader。
40.networks考生可以听到定位词Marine Mammals Ashore后面出现的finding out more about these networks,即前文提到的stranding networks,因此答案为networks。
注意剑桥答案还给了network,但还是建议考生考试时听见什么写什么,不要随意更改名词的单复数。
(一)由于考试政策等各方面情况的不断调整与变化,本网站所提供的考试信息仅供参考,请以权威部门公布的正式信息为准。
(二)本网站在文章内容来源出处标注为其他平台的稿件均为转载稿,免费转载出于非商业性学习目的,版权归原作者所有。如您对内容、版 权等问题存在异议请与本站联系,我们会及时进行处理解决。"