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
"How the zebra got his stripes" sounds like the title of one of Rudyard Kipling’s "Just So" stories. Sadly, it isn’t, so the que
"How the zebra got his stripes" sounds like the title of one of Rudyard Kipling’s "Just So" stories. Sadly, it isn’t, so the que
admin
2012-12-01
32
问题
"How the zebra got his stripes" sounds like the title of one of Rudyard Kipling’s "Just So" stories. Sadly, it isn’t, so the question has, instead, been left to zoologists. But they, too, have let their imaginations rip. Some have suggested camouflage. Others suggest they are a way to display an individual’s fitness. Irregular stripes would let potential mates know that someone was not up to snuff. One researcher proposed that stripes are to zebra what faces are to people, allowing them to recognise each other, since every animal has a unique stripe-print. Another even speculated that predators might get dizzy watching a herd of stripes gallop by. There is, however, one other idea: that stripes are a sophisticated form of fly repellent. It was originally dreamed up in the 1980s, but never proved. Now, a team of investigators led by Gabor Horvath of Eotvos University in Budapest report in the Journal of Experimental Biology that they think they have done so.
The original suggestion was that stripes repel tsetse flies. These insects carry sleeping sickness, which is as much a bane of ungulates as it is of people. But tsetses are not the only dipteran foes of zebra and, since they are rarely found in the meadows of Hungary, Dr Horvath plumped for studying an almost equally obnoxious alternative: the horsefly. Horseflies, too, transmit disease. They also bite incessantly, thus keeping grazing beasts from their dinner. Indeed, previous research has shown that fly attacks on horses and cattle reduce their body fat and milk production. Such research has also shown something odd: horseflies attack black horses in preference to white ones. That fact got Dr Horvath wondering how they would react to a striped horse—in other words, a zebra.
Actual zebra are hard to experiment on. They insist on moving around and swishing their tails. The team therefore conducted their study using inanimate objects. Some were painted uniformly dark or uniformly light, and some had stripes of various widths. Some were plastic trays filled with salad oil. Some were glue-covered boards. And some were actual models of zebra. They put these objects in a field infested with horseflies and counted the number of insects they trapped.
Their first discovery was that stripes attracted fewer flies than solid, uniform colours. As intriguingly, though, they also found that the least attractive pattern of stripes was precisely those of the sort of width found on zebra hides. Zebra stripes do, therefore, seem to repel horseflies. Exactly why is unclear. But Dr Horvath thinks it might be related to a horsefly’s ability to see polarised light, which imposes a sense of horizontal and vertical on an image. Horseflies are known to prefer horizontal polarised light. Possibly, the mostly vertical stripes on a zebra confuse the fly’s tiny brain and thus stop it seeing the animal.
Another obvious question, though, is why other species have not evolved this elegant form of fly repellent, and what the consequences would have been if they had. If humans, for example, were black-and-white striped then the history of intercommunal violence the species has suffered when different races have met might not have been quite as bad. One for Kipling to have pondered, perhaps?
Which one of the following is NOT mentioned as the imagined reasons why zebra got strips?
选项
A、Stripes allow zebra to recognise each other.
B、Strips are a way to display an individual’s fitness.
C、Strips allow zebra to show their beauty.
D、Stripes are a sophisticated form of fly repellent.
答案
C
解析
细节题。C项为正确答案。不符合课文的只有C项内容。因为斑马纹的主要功能并不是为了比美。
转载请注明原文地址:https://kaotiyun.com/show/7haO777K
0
专业英语八级
相关试题推荐
Inthe1950s,thedevelopmentofantipsychoticdrugscalledneuroleptics(抑制精神病药物)radicallychangedtheclinicaloutlookforpat
WhichofthefollowingisthelargestprovinceinCannada?
Itishardtoconceiveofalanguagewithoutnounsorverbs.ButthatisjustwhatRiauIndonesianis,accordingtoDavidGil,a
A、Theyarehinderedbyrain,blockedroads,etc.B、TheyaremadebyManila’sGMAtelevision.C、Philippineairforcehasjoinedi
TheBibleitselfcontainsatotalof66booksandisdividedintotwoparts,theOldTestamentandtheNewTestament.TheOldTe
______isthestudyofspeechsoundsinlanguageoralanguagewithreferencetotheirdistributionandpatterningandtotacitr
Insocialsituations,theclassicIntentionMovementis"thechair-grasp"Hostandguesthavebeentalkingforsometime,butno
______isthestudyofthephysicalpropertiesofthesoundsproducedinspeech.
AlthoughChopinlaterattendedtheLyceumwherehisfathertaught,hisearlytrainingbeganathome.Thisincludedreceivingpia
随机试题
我们要扩大同世界各国的利益交汇点,推进大国协调和合作,构建总体稳定、均衡发展的大国关系框架,按照()周边外交方针深化同周边国家关系。
浮小麦主治的病症是
下面哪个不是覆、覆盖的重要生理意义
从事期货投资咨询业务的其他期货经营机构,应当取得()批准的业务资格。
证券公司申请发行债券,发行人应结合中国证监会对发行申请文件的审核反馈意见提供补充材料,发行人全体董事应对随后申报的补充内容出具书面回复函。()
某普通合伙企业存续期间,合伙人甲准备向合伙人以外的乙转让其在合伙企业中的部分财产份额时,如果合伙协议对此没有约定,正确的做法是()。
下列收入项目中,应按税法规定,计算缴纳个人所得税的是()。
Inrecentyearsmanycountriesoftheworldhavebeenfacedwiththeproblemofhowtomaketheirworkersmoreproductive.Somee
合伙经营积累的财产通常是由
WartenSiebitte!____fünfMinutenkommterzurück.(nach,in,ab)
最新回复
(
0
)