首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Why don’t birds get lost on their long flights from one place to another? Scientists have puzzled over this question for many ye
Why don’t birds get lost on their long flights from one place to another? Scientists have puzzled over this question for many ye
admin
2015-12-31
67
问题
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’re 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 (鸽子) had spent its 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 (航行) only. When the stars are hidden by clouds, they seemingly 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.
The experiment with the dove indicated 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
文中第三段第二句、三句说:“然而它显示出与生俱来的用星星作导航的能力。装这只鸽子的笼子是被安放在充满人造星星的天空下面。”结合第二段最后一句,“使用人造星星的实验证明:一些长距离飞行的鸟在夜里能够沿着星星的方向飞”。由此我们可以得出选项D正确。其余三个选项均不符合文章内容。
转载请注明原文地址:https://kaotiyun.com/show/l2PO777K
0
在职攻硕英语联考
相关试题推荐
Man:Thesnowisreallycomingdown,isn’tit?Woman:RarelydowegetsomuchsnowinDecember.Question:Whatdoesthewomanm
Man:Doyouwanttoturnontheair-conditioneroropenthewindows?Woman:Ilovefreshairifyoudon’tmind.Question:Whatc
Inthispassage,scientistswarnof______.Accordingtothepassage,inthelongrun,abruptclimatechange______.
Inthispassage,scientistswarnof______.Oneofthemostimmediatedangersposedbyabruptclimatechangeis______.
Woman:Henry,yourarticleinthecampusnewswasexcellent.Man:Ionlywishtheyhadpublishedtheentirething.Question:Wha
ThelargesizeandroughlycircularshapeofthePacificmadesomescientiststhinkthatit______aholeleftwhenthemoonsep
Man:Myfathercandocooking,carpentry,andabitofgardening.Woman:He’saJackofalltrades,really.Question:Whatdoes
By"itspokevolumestome",(Para.1)themotherinthestorymeansthecard______.Whatpuzzledthemotherwhenherdaughter
随机试题
某大型工程施工项目发生质量事故,造成20人死亡,直接经济损失为8000万元,此类事故为()。
甲状旁腺损伤后,治疗手足搐搦最有效的方法是
发盘
提出把党的工作重心由乡村转移到城市的会议是()。
《刑法》规定,在拐卖妇女、儿童过程中奸淫被拐卖的妇女的,仅定拐卖妇女、儿童罪。15周岁的甲在拐卖幼女的过程中,强行奸淫幼女。对此,下列哪些选项是错误的?()
资本主义工商业实行社会主义改造经历了三个步骤,初级形式的国家资本主义在利润分配上采取的政策是()
y=,则y’=________.
当前奔腾(Pentium)微处理器的工作主频率通常为( )。
Thehunter-gatherertribesthattodaylivelikeourprehistorichuman【M1】______ancestorsconsumeprimarilyavegetabledietsu
A--generalexpenseB--governmentdebtC--grossdomesticproduct(GDP)D--grossearn
最新回复
(
0
)