首页
登录
职称英语
[originaltext] America’s national symbol—the Bald Eagle—almost went extinct
[originaltext] America’s national symbol—the Bald Eagle—almost went extinct
游客
2023-09-09
17
管理
问题
America’s national symbol—the Bald Eagle—almost went extinct 20 years ago. But it has made a comeback In fact, the US Fish and Wildlife Service is considering the possibility of taking it off the endangered species list. Once, more than 50 000 pairs of bald eagles nested across the country. But by 1960, that number had fallen below 400. The chief killer was the widely used DDT. Fish soaked up DDT died and were washed up on shores where bald eagles feasted on them. (29)DDT prevented eagle eggshells from thickening. The shells became so thin that they shattered before the babies hatched. Fortunately, in 1972, a law was passed to ban DDT. which saved the bald eagle from total wipeout. (30)And since then, wildlife biologists have reintroduced bald eagle eggs from Canada to America. The result was that last year US bird watchers counted 11 610 bald eagles in the country. If it were dropped from the endangered list, the bald eagle would still be a threatened species. That means the bird would continue to get the same protection—no hunting allowed, and no disturbing of nests. (31)But bald eagles still face tough times. The destruction of their natural homes could be the next DDT causing eagle numbers to drop quickly.
选项
A、It limited their supply of food.
B、It made their eggshells too fragile.
C、It destroyed many of their nests.
D、It killed many baby bald eagles.
答案
B
解析
事实细节题 。原文提到,DDT使得蛋壳变得很薄,在小鹰孵化之前就碎了,故本题选择B项。
转载请注明原文地址:https://tihaiku.com/zcyy/2997720.html
相关试题推荐
[originaltext]IntheUSwehavefreecompulsorypubliceducationforallch
[originaltext]IntheUSwehavefreecompulsorypubliceducationforallch
[originaltext]W:Hey,Joe.What’sallthistalkaboutabenefitwalkathonthis
[originaltext]W:Hey,Joe.What’sallthistalkaboutabenefitwalkathonthis
[originaltext]M:Hi,Jane.Howisyourvacation?W:Terrific!IwenttoWashing
[originaltext]Inwesternculturemusicisregardedasgoodbybirth,andso
[originaltext]Inwesternculturemusicisregardedasgoodbybirth,andso
[originaltext]Theworld’ssmartadolescenceinmathematicsandscienceare
[originaltext]Theworld’ssmartadolescenceinmathematicsandscienceare
[originaltext]Aristotle,fileGreekphilosopher,summedupthefourchiefq
随机试题
[originaltext]StudentsinAmericanschoolslearnfromanearlyagetogive
【C1】______twoyearslivingtogether,ayoungcoupleexperiencedtheusualu
Negativestressiswhatmostofusthinkofwhenwethinkofstress.Andneg
()是在一个水平投影面上标有高度数字的正投影图。常用来绘制地形图和道路、水利工程
根据《证券公司流动性风险管理指引》的规定,流动性覆盖率与净稳定资金率应均不低于(
假若你是幼儿园园长,你们幼儿园有部分优秀教师下班时间在家辅导学生,你对这种现象怎
《变电验收管理规定第26分册辅助设施验收细则》:变电站电缆沟应在()处设置阻火
《变电验收管理规定第26分册辅助设施验收细则》:改扩建工程采用的防误闭锁装置型式
2016年11月,下列地区中原煤产量同比下降最多的是( )。A.上海
在机床电力拖动中,要求液压泵电动机起动后主轴电动机才能起动,液压泵电动机接触器是
最新回复
(
0
)