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
考研
In matters biological, whether large or small, it is a good bet that what Charles Darwin said back in the 19th century is correc
In matters biological, whether large or small, it is a good bet that what Charles Darwin said back in the 19th century is correc
admin
2016-03-21
69
问题
In matters biological, whether large or small, it is a good bet that what Charles Darwin said back in the 19th century is correct. One idea he had, which has not hitherto been put to the test, is that waterborne invertebrates frequently spread by hitching lifts on birds. On this, it turns out, he was right as well.
Darwin noticed that when he suspended a duck’s foot in an aquarium, invertebrate larvae attached themselves to it and held on tight for many hours, even if he removed it from the water. Sadly, he died before he could explore this phenomenon in the wild. But Joseph Simonis and Julie Ellis just have.
Dr. Simonis, who works at Lincoln Park Zoo in Chicago, and Dr. Ellis, of Tufts University in Massachusetts, put Darwin’s idea to the test on Appledore Island in Maine, where thousands of rain-filled rock pools sit. These pools host such animals as water fleas, rotifers and seed shrimps. Since these creatures are incapable of cross dry land by themselves, the two researchers thought they might be making use of birds to hop between pools, as Darwin suggested.
Dr. Simonis and Dr. Ellis therefore collected 25 young gulls that had been dabbling in the pools(juveniles are easier to catch because they cannot yet fly)and 25 others that they had followed for at least 20 minutes, and had not seen go into a pool in that time. They gave every bird a bath in a tub of water for five minutes and sieved the water afterwards to see what had floated off.
They report in Ecology that 16 of the gulls which had been dabbling carried larvae or viable eggs when they were given their enforced bath. One, indeed, had 18 such creatures attached to it. Of those gulls that had been away from the water, only two carried hitchhiking invertebrates. Gulls, then, certainly are picking up passengers when they bathe. But are they dropping them at suitable destinations?
The answer to that seems to be "yes" , too. Pools in areas with lots of gulls shared 80% of their species. That dropped to 50% in places where the birds were few and far between. It therefore looks as though gulls are homogenising the local ecosystems by carrying invertebrates around. Chalk another one up to Charles.
Dr. Simonis and Dr. Ellis’s experiment has proved that______.
选项
A、birds are enemies of the creatures in the water
B、birds may carry some creatures from the water
C、only gulls carry some creatures when they bathe
D、the creatures in the water can’t survive without birds
答案
B
解析
文章第四、五两段主要描述Dr.Simonis和Dr.Ellis的实验,而第四段更注重实验过程,第五段注重实验结果,其中明确体现出实验结果的是第五段倒数第二句:Gulls,then,certainly are picking up passengers when they bathe.“显然,海鸥在戏水的时候带上了‘乘客’”。四个选项与之相等的是选项[B]birds may carry some creatures from the water,其中birds=gulls;carry some creatures=picking up passengers;from the water=when they bathe;故本题答案为[B]。
转载请注明原文地址:https://kaotiyun.com/show/sasZ777K
0
考研英语一
相关试题推荐
Parentsandgrandparentswithmoneytosparearenolongerwaitinguntildeathtopassontheirwealth.Instead,they’reincreas
Leadinguptothedebt-ceilingdeadline,everyonewastalkingabouthowthestockmarketwouldcraterifWashingtondidn’treach
[A]Tosomeextent,thispublichostilityiswelldeserved.ThebankruptciesofEnronintheU.S.andParmalatinItalylastwee
Thereisnomarketwithoutincome,andtheyouthsegmentqualifiesonthisimportantdimension.Theirspendingreachedabout$55
Whiletravelingforvariousspeakingengagements,Ifrequentlystayovernightinthehomeofafamilyandamassignedtooneof
Manywilldoubttobaccoindustryclaimsthatitissharpeningitssciencetoevaluate"healthiercigarettes".Butthat’swhatwi
Dieting,accordingtoanoldjoke,maynotactuallymakeyoulivelonger,butitsurefeelsthatway.Nevertheless,evidencehas
Thatmythicalbeast,homoeconomicus,otherwisecalledEconomicman,isutterlyclearaboutthepurposeofwork:togetpaid.He
PresidentBarackObamaclaimedprogressWednesdayinhissecond-termdrivetocombatclimatechangebutsaidmoremustbedonet
Thinkofthosefleetingmomentswhenyoulookoutofanaeroplanewindowandrealisethatyouareflying,higherthanabird.No
随机试题
下列哪项不是肾性高血压的特点
适用橡胶手套的消毒方法是
血浆游离血红蛋白增高的有关检验有
胃痞的辨证要分辨
食管癌最多见的病理类型为
某宗房地产的成交价格为4000元/m,卖方缴纳的税费为成交价格的8%,买方缴纳的税费为成交价格的5%。卖方的净得为()元/m。
法的目的在于确认、保护和发展有利于统治阶级的()。
正态均值μ的无偏估计有()。
有人去你办公室当众大吵大闹,指责你工作不负责任,怎么办?
在考生文件夹下,打开文档WORD1.DOCX,按照要求完成下列操作并以该文件名(WORD1.DOCX)保存文档。(1)将文中所有“最低生活保障标准”替换为“低保标准”;将标题段文字(“低保标准再次调高”)设置为三号楷体、居中、字符间距加宽3磅、并
最新回复
(
0
)