首页
登录
职称英语
Why don’ t birds get lost on their long flights from one place to another? S
Why don’ t birds get lost on their long flights from one place to another? S
游客
2023-10-02
53
管理
问题
Why don’ t birds get lost on their long flights from one place to another? Scientists have puzzled over this question for a long time. Now they’ re starting to fill in the blanks.
Not long ago, experiments showed that birds use the sun to guide them during daylight hours. How do birds fly at night? Tests with artificial stars have proved that certain night-flying birds are able to follow the stars in their long-distance flights.
A dove had spent its lifetime in a cage and had never flown under a natural sky. But it had an inborn ability to use the stars for guidance. The bird’s cage was placed under an artificial star-filled sky. The bird tried to fly in the same direction as that taken by his outdoor cousins. Any change in the position of the artificial stars caused a change in the direction of his flight.
But the stars are apparently their main means of navigation. When the stars are hidden by clouds, they apparently find their way by such landmarks as river courses, mountain ranges, coast lines. But when it’ s too dark to see these things, the doves circle helplessly, unable to find their way. [br] The experiment with the dove indicates that______.
选项
A、birds have to be taught to navigate
B、a bird that has been caged will not fly long distances
C、some birds cannot fly at night
D、some birds seem to follow the stars when they fly at night
答案
D
解析
题干意为“鸽子的实验表明 。”选项A从第三段“But it had an inborn ability to use the stars for guidance.”可以排除。解题关键是从第二段的最后一句话“Tests with artificial stars have proved that certain night—flying birds are able to follow the stars in their long—distance flights.”可排除B、C,并推理出D项为正确答案。
转载请注明原文地址:http://tihaiku.com/zcyy/3065905.html
相关试题推荐
Itisa(regret)______thingtomakeanotherpersonsuffer.regretful
[originaltext]W:Hello.IwonderwhetherIcanbookmyroomforanothertwonig
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Thereasonwhybirdsdon’tgetlostonlongflights______.[br]By"hisoutdoor
Itisa(regret)______thingtomakeanotherpersonsuffer.regretful
All______toHongKongweredelayedbecauseofbadweather.A、flyB、flightsC、fl
NotonlyIbutalsoJaneandMaryaretiredofhavingonemeetingafteranother.
Whatmakesonepersonmoreintelligentthananother?Whatmakesonepersona
随机试题
Youaretowriteinnolessthan120wordsaboutthetitle"ShouldEducation
Whatkindofjobsmaymendobest,accordingtothepassage?[br][originaltext
It’snicetohavepeopleoflikemindaround.Agreeablepeopleboostyourco
PC1接入Internet的拓扑如下图所示,其中Server1为Web服务器,则
回答有关压实度的问题。(4)一般来说,测定沥青面层压实度的方法有()。A.
建设项目财务评价与国民经济评价的区别主要有()。A.评价的角度不同 B.采用
(2020年真题)某住宅楼工程,地下2层,地上20层,建筑面积2.5万平方米,基
肾病综合征的特点A、低白蛋白血症 B、高脂血症 C、明显水肿 D、大量蛋白
以下行为中属于招标人与投标人串通行为的有()。A.就同一招标项目向投标人提供有
对分包单位的连带责任,下列说法正确的是()。A.有关工程总分包的连带责任,不属于
最新回复
(
0
)