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
2024-12-25
31
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/3883469.html
相关试题推荐
______studiesspeechsounds,includingtheproductionofspeech,thesoundsof
"Howthezebragothisstripes"soundslikethetitleofoneofRudyardKipl
"Howthezebragothisstripes"soundslikethetitleofoneofRudyardKipl
"Howthezebragothisstripes"soundslikethetitleofoneofRudyardKipl
"Howthezebragothisstripes"soundslikethetitleofoneofRudyardKipl
Thebranchoflinguisticswhichstudiesthecharacteristicsofspeechsoundsand
Thestudyofhowsoundsareputtogetherandusedtoconveymeaningincommunica
Allofthefollowingpairsofsoundsexcept______aredistinguishedfromeacho
Whatarethedualstructuresoflanguage?A、Soundsandletters.B、Soundsandmean
Bothof_____areconcernedwiththestudyofspeechsounds.A、Phonologyandseman
随机试题
AsIamsureJennyisveryhonest,I______thatshestolethemoney.A、guessB、bel
生活就像一杯红酒,热爱生活的人会从其中品出无穷无尽的美妙。(2013年真题)Lifeisaglassofredwine,fromwhichl
Icryeasily.IonceburstintotearswhenthecurtaincamedownontheKirov
肛管术后几天内无大便,应每晚口服液状石蜡A.1~2天B.3天C.5~6天D.7~
高层建筑内的乘客电梯,轿厢内的应急照明连续供电时间不少于( )。A.20min
PCR技术可用于( )。A.某些遗传病的治疗 B.检测微量目的基因 C.基
QDII基金份额净值应当至少____计算并披露一次,如基金投资衍生品,应____
有关医疗机构制剂管理的说法,正确的是A.向患者提供的制剂应当与诊疗范围相适应,并
(2020年真题)2020年3月,某生产企业出口自产货物销售额折合人民币
某区域电网中的一座500kV变电所,其220kV母线单相接地短路电流超标,请问采
最新回复
(
0
)