首页
登录
职称英语
Why don’t birds get lost on their long flights from one place to another? Sc
Why don’t birds get lost on their long flights from one place to another? Sc
游客
2023-10-02
48
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] By "his outdoor cousins" the author means______.
选项
A、other experimenters
B、the other doves of the same brood
C、doves under the natural sky
D、other birds in general
答案
C
解析
A项“其他实验者”;B项“其他同一窝的鸽子”;C项“在自然天空下飞行的鸽子”;D项“其他鸟类”。根据题意,C为正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3064638.html
相关试题推荐
(give)______anotherchance,IamsureIcandoitbetter.Given。本句非谓语动同短语在句中作状语
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Whydon’tbirdsgetlostontheirlongflightsfromoneplacetoanother?S
Thereasonwhybirdsdon’tgetlostonlongflights______.[br]Intotaldarkne
Thereasonwhybirdsdon’tgetlostonlongflights______.[br]Theexperiment
Thereasonwhybirdsdon’tgetlostonlongflights______.[br]By"hisoutdoor
Thereasonwhybirdsdon’tgetlostonlongflights______.[br]Duringdaylight
All______toHongKongweredelayedbecauseofbadweather.A、flyB、flightsC、fl
Jacklosthisjobayearagoandhe______anotherjobyet.[originaltext]时态[/ori
随机试题
Thestaffinyourofficedecidedtospendholidaystogetherthisyear.While
Whydoesn’tthemancarryacamerawithhim?[br][originaltext]M:Didyoutake
立杆钢管的表面质量和外形应是()。A.平直光滑,无锈蚀、裂缝、结疤、分层、硬弯
已经批准的上一层次规划为城乡规划的编制依据之一,因城乡规划的范围大小不同,其规划
劳动法律关系的主要形态是( )。A.劳动行政法律关系 B.劳动合同关系
在设计人事调动评价表时,主要包括哪几方面的内容?
肾的主要生理功能有A.主宰水液代谢 B.闭藏先天之精 C.贮藏尿液 D.受
正是因为畏惧和仇视舆论监督,少数无良官吏要绞尽脑汁甚至是_地扼杀舆论监督。个别
赵、钱、孙三人欲投资设立甲有限责任公司,在章程中对甲公司监事会作出的如下规定中正
(2015年真题)根据《建筑法》及相关法规,建设单位应当办理施工许可证的工程是(
最新回复
(
0
)