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
68
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]The19thcenturyWildWestcriminalBillytheKidhasbeende
Theresearchisobviouslypainstaking:theauthorincludesalargeglossaryofm
Whoisthewoman?[br][originaltext]M.ProfessorRuskin,couldIspeaktoyou?
以下关于唇裂、腭裂的叙述,哪项是错误的()A.唇裂病员无法形成“腭咽
29岁已婚妇女,平素月经规则,LMP:2012-05-17。于2012-06-2
(1)新产品试制(2)新产品质检合格(3)市场部反映市场需求(4)研发部根据需求
患者,男,40岁,醉酒后骑摩托车摔倒路边,前额处有一较深伤口,遵医嘱,行破伤风抗
患者,女性,80岁。因慢性支气管炎感染后加重而入院,患者咳嗽加重,痰量增多,体温
2016年,A市直接经济价值年值占现代农业生态服务价值年值的比重为:A.8.
下列项目中,二级注册建造师可以担任工程项目负责人的是( )。A.单项工程合同额为
最新回复
(
0
)