首页
登录
职称英语
The reason why birds don’t get lost on long flights ______. [br] [originaltext]
The reason why birds don’t get lost on long flights ______. [br] [originaltext]
游客
2023-11-14
39
管理
问题
The reason why birds don’t get lost on long flights ______. [br]
Why don’t birds get lost on their long flights from one place to another? Scientists have puzzled over this question for many years. Now they are beginning to fill in the blanks.
Not long ago, experiments showed that birds rely on the sun to guide them during daylight hours. But what about birds that fly by 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 his lifetime in a cage and had never flown under a natural sky. Yet it showed 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 principal means of navigation. When the stars are hidden by clouds, they apparently find their way by such landmarks as mountain ranges, coast lines, and river courses. But when it’s too dark to see these, the doves circle helplessly, unable to find their way.
选项
A、rely on landmarks
B、don’t know which way to fly
C、fly back home
D、wait for the stars to appear
答案
B
解析
转载请注明原文地址:https://tihaiku.com/zcyy/3184987.html
相关试题推荐
Whatisthethemeoftheforum?[br][originaltext]Aneconomicforum—onO
Thedemonstrationisto______.[br][originaltext]Onthesecondanniversa
Whywasthespeedlimitfirstreducedto55miles-per-hour?[br][originaltext]
Whatarethewaysanimalscommunicate?[br][originaltext]Whenwethinkof
Whatarethewaysanimalscommunicate?[br][originaltext]Whenwethinkof
Whatarethewaysanimalscommunicate?[originaltext]Whenwethinkofcommu
Thetwospeakersaremainlytalkingabout______.[br][originaltext]M:Hi,Jan
WhatdidIndonesiaandAcehrebelsdoonMonday?[originaltext]Indonesiana
WhyAmericanscientistsaredevelopingthesemaps7[br][originaltext]Americ
WhyAmericanscientistsaredevelopingthesemaps7[br][originaltext]Americ
随机试题
[originaltext]M:NowI’lltakesomequestions.W:Well,Mr.Brown,Ihaveaque
A.disgracefulB.imperfectC.holdD.considerationE.approvedF.acco
Youshouldspendabout20minutesonQuestions1-13whicharebasedonReadingP
ThePlayofPower:AnIntroductiontoAmericanGovernmentJ
下列不符合前尿道瓣膜及憩室临床表现的是A.排尿困难、尿滴沥 B.膀胱内大量残余
下列关于开展个人贷款业务的意义的说法中,错误的是()。A.帮助银行消除风险
Thechangeinthatvillagewasmiraculou
阿司匹林的水杨酸反应不包括A.耳鸣、耳聋B.呼吸抑制C.头痛、眩晕、晕厥D.酸中
采购部门与其他部门的关系可以大致分成四种类型,不属于这四类关系的为().A.混
目前电站汽轮机低压外下缸组合时气缸找中心的基准通常采用()。A.激光 B
最新回复
(
0
)