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
Since there is such an abundance of food in the sea, it is understandable that some of the efficient, highly adaptable, warm-blo
Since there is such an abundance of food in the sea, it is understandable that some of the efficient, highly adaptable, warm-blo
admin
2013-02-16
34
问题
Since there is such an abundance of food in the sea, it is understandable that some of the efficient, highly adaptable, warm-blooded mammals that evolved on land should have returned to the sea. Those that did do that have flourished. Within about 50 million years—no time at all, geologically speaking —one of the four kinds of mammals that has returned to a marine environment has developed into the largest of all animal forms, the whale. A second kind, the seal, has produced what is probably the greatest population of large carnivorous mammals on Earth. This suggests that these "top dogs" of the ocean are prospering and multiplying. However, such has not been the case, at least not for the last 150 years. Trouble has closed in on these mammals in the form of equally warm-blooded and even more efficient and adaptable predators, humans. At sea, as on land, humans have now positioned themselves on top of the whole great pyramid of life, and they have caused serious problems for the mammals of the sea.
There is a simple reason for this. Marine mammals have the misfortune to be swimming aggregates of commodities that humans want: fur, oil, and meat. Even so, they might not be so vulnerable to human depredation if they did not, like humans, reproduce so slowly. Every year humans take more than 50 million tons of fish from the oceans without critically depleting the population of any species. But the slow-breeding mammals of the sea have been all but wiped out by humans seeking to satisfy their wants and whims.
It can be inferred from the passage that during the last 150 years humans have ______.
选项
A、constructed submarines
B、learned how to swim
C、threatened the existence of some marine mammals
D、begun to harvest certain plants from the ocean as food
答案
C
解析
根据文章第一段最后四句可知,这些海洋中的“大哥大”们人丁兴旺,一派繁荣景象。但事实并非如此,至少在过去150年来是这样。同样是暖血动物而且效率更高、适应性更强的捕食者——人类,已成为这些哺乳动物日益迫近的威胁。和在陆地一样,人类在海洋也已处在巨大的生物金字塔的最顶端,成为所有生物的主宰,给海洋哺乳动物带来严重威胁。据此判断,答案是C。
转载请注明原文地址:https://kaotiyun.com/show/qbmO777K
0
考博英语
相关试题推荐
Whatdoconsumersreallywant?That’saquestionmarketresearcherswouldlovetoanswer.Butsincepeopledon’talwayssaywhat
TheIntergovernmentalPanelonClimateChangeconcludedthatglobalwarmingisnogame.Theyprovideevidencethatheat-trapping
The______friendwasexposedintheendtobeahiddenrivalwhohadbeenplottingagainstthecompany’smarketinginHongKong
Travellingandmeetingnewpeople______themindofyoungpeople.
Therearesomanynewbooksaboutdyingthattherearenowspecialshelvessetasidefortheminbookshops,alongwiththehealt
Forthispart,youarerequiredtowriteacompositionofatleast250wordsaccordingtothefollowinginstruction."Somepeopl
Inrecentyears,Israeliconsumershavegrownmoredemandingasthey’vebecomewealthierandmoreworldly-wise.Foreigntraveli
"ItwasthebeginningofarevolutioninAmericaandtheworld,arevolutionthatsomehaveyettoacknowledgeandmanyhaveyet
MysonJoeywasbornwithclubfeet.Thedoctorsassuredusthatwithtreatmenthewouldbeabletowalknormally—butwouldneve
______anyoneshouldthinkitstrange,letmeassureyouthatitisquitetrue.
随机试题
易致血糖升高:恢复过程中易致幻觉、恶梦多
中医辨证为:治疗最佳方剂是:
按我国现行土地利用分类,下列项目用地中不属于特殊用地的有()。
关于税务规章,下列说法中正确的是()。
2009年3月2日,A公司与B公司签订了一份100万元的设备买卖合同。该合同约定:A公司于3月3日向B公司签发一张金额为人民币15万元的银行承兑汇票作为定金;B公司于3月10日交付设备;A公司于B公司交付展览设备之日起3日内付清货款;任何一方违约,
测量结果与在重复性条件下,对同一被测量进行无限多次测量所得的结果的平均值之差称为()。
中共七大确立毛泽东思想为党的指导思想()。
就目前房地产市场成交量增加的现象,有分析认为,中国地产引擎可能重新启动。果真如此的话,这将在外需出现困境的背景下引领中国经济走出低谷。对比1986年日本的情况,如果政府引导得当,中国经济将可能因为地产业的重新启动而率先走出困局。当然,基于美国当年的经验,经
移动互联网医疗是指利用移动终端和以互联网为载体,开展健康咨询、疾病评估、挂号缴费等医疗健康服务的新兴行业。根据上述定义,下列不属于移动互联网医疗的是:
WhatmayAnngotoLondonfor?
最新回复
(
0
)