首页
登录
职称英语
"How the zebra got his stripes" sounds like the title of one of Rudyard Kipl
"How the zebra got his stripes" sounds like the title of one of Rudyard Kipl
游客
2023-12-13
8
管理
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? [br] It can be inferred from the passage that the reason why actual zebra are hard to experiment on is that______.
选项
A、horseflies transmit disease
B、they insist on moving around and swishing their tails
C、the mostly vertical stripes on a zebra confuse the fly’s tiny brain and thus stop it seeing the animal
D、zebra graze in the open, not amid thick vegetation where a striped pattern might break up their outlines
答案
B
解析
推断题。斑马难以被实验的原因主要是他们不断地移动并且不停的甩动尾巴。由原文“Actual zebra are hard to experiment on.They insist on moving around and swishing their tails.”,可得出答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3268911.html
相关试题推荐
Bothof_____areconcernedwiththestudyofspeechsounds.A、Phonologyandsema
TheoriginalAmericanflagcontains13horizontalstripesand13whitestarsarr
TheoriginalAmericanflagcontains13horizontalstripesand13whitestarsarr
HernamesoundsfamiliarwithmebutIcan’ttellwhosheisatthemoment.with—
______wasawardedtheNobelPrizeforLiteraturein1907.A、JosephRudyardKiplin
______isthestudyofthewayinhowmorphemes,representationofsounds,arear
PhonologyisthestudyofA、howspeechsoundsaremade.B、thesoundsystemoflan
______isthestudyofthephysicalpropertiesofthesoundsproducedinspeech.A
TherepetitionoftheinitialconsonantsoundsinpoetryiscalledA、simile.B、al
______studiesspeechsounds,includingtheproductionofspeech,thesoundsof
随机试题
NarratorListentopartofatalkinananthropologyclass.Nowge
Peopletravelinglongdistancesfrequentlyhavetodecideif【M1】______they
马云(JackMa)是阿里巴巴(Alibaba)集团的创始人之一和董事会主席。十五年前,在他的公寓里,十八位创始人有了一个梦,那就是,在某一天能够创立
下列氨基酸中,直接参与嘌呤环和嘧啶环合成的是:A.天冬氨酸 B.谷氨酰胺 C
保险规划的主要功能是(??)。A.获取收益 B.转移和规避风险 C.资产增值
再造散与败毒散的组成中均含有的药物是A.附子、柴胡、桂枝B.羌活、川芎、人参C.
证券公司申请设立子公司有两种形式分别是()。A:设立全资子公司 B:与符合《投
神经衰弱的常见生理症状包括()。(2009-11)A:长期睡眠少且感到痛苦B:
咽旁间隙感染的临床特点,错误的是A.常由下颌智齿冠周炎引起 B.可出现吞咽疼痛
关于原发型肺结核,下列错误的是A.初次感染病灶多在上叶底部、中叶或下叶上部,常邻
最新回复
(
0
)