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
The ostrich, the largest bird in the world at present, lives in the drier regions of Africa outside the actual deserts. Because
The ostrich, the largest bird in the world at present, lives in the drier regions of Africa outside the actual deserts. Because
admin
2010-01-09
84
问题
The ostrich, the largest bird in the world at present, lives in the drier regions of Africa outside the actual deserts. Because of its very long, powerful legs and the floating effect of its extended wings, it is able to run at great speed over considerable distances.
The female ostrich normally produces about twenty eggs every rainy season. When the female ostrich begins to lay her eggs, however, she does not begin in her own nest. Instead she goes off in search of the nests of neighboring females and lays two or three eggs in each of them. By the time she has laid eight or nine eggs, she returns and lays the rest in her own nest.
Because of the size of the eggs, the female ostrich cannot lay more than one every two days, so it takes her three weeks to finish laying in her own nest. During that period, she spends a lot of time away from her nest looking for food. And while she is off her nest, other females visit it to lay their eggs amongst hers. By the time she is ready to sit on the eggs to hatch them, there could be up to thirty eggs in her nest, over half of which are not her own.
The female ostrich can comfortably cover only about twenty eggs when she is sitting on the nest so before settling down she pushes the surplus ten or so eggs out of the nest. The rejected eggs, however, never include any of her own. Each female is remarkably consistent in the size and shape of the eggs she produces, so it is not difficult for her to distinguish her own from those of strangers.
Of all the eggs laid by a colony of ostriches, only a very small number hatch into young birds. There are times when nests are left unprotected, for there are too few males to sit on all the nests at night. Thus there are ample opportunities for their natural enemies to raid the nests and eat the eggs. In fact, nearly 80% of the nests are destroyed. But even if a particular female’s nest suffers this fate, there is a good chance that one or two of her eggs will be hatched in the nest of one of her neighbors.
The female ostrich identifies her own eggs by their size and ______.
选项
A、color
B、number
C、shape
D、weight
答案
C
解析
细节题。根据第四段第三句知对于每只雌鸵鸟来说,他们产的蛋有固定的大小和形状,故分辨自己所产的蛋对于他们来说并不难。所以答案为C。
转载请注明原文地址:https://kaotiyun.com/show/Ls3d777K
本试题收录于:
公共英语三级笔试题库公共英语(PETS)分类
0
公共英语三级笔试
公共英语(PETS)
相关试题推荐
Generallyspeaking,aBritishiswidelyregardedasaquiet,shyandconservativepersonwhois【21】onlyamongthosewithwhomhe
Nowadays,airtravelisvery【21】.WearenotsurprisedwhenwewatchonTVthatapoliticianhastalkedwithFrenchPresidentin
Aspartofmorecomprehensivecomplianceandethicsprograms,manycompanieshaveformulatedinternalpoliciespertainingtothe
Psychologistssaytheonefactorthatdifferentiatespeoplewhoarecreativefromthosewhoaren’tisbelief-creativepeoplebel
maintaininghealthyteeth
ImmediatelyaftertheCivilWar,however,thedietbegantochange.(61)Railtransportationincreasedthesupplyandimprovedt
In1987,therewereover1.5millionviolentcrimesreportedintheUnitedStates.Mostofthisviolencecomesfromaggressivep
Nobodycanbereallyfreefromthesound.Whetherweliveinthemiddleofamodemcityorafarawayvillage,wearesurrounded
ManyUnitedStatescompanieshave,unfortunately,madethesearchforlegalprotectionfromimportcompetitionintoamajorline
Accordingtothepassage,theaverageI.Q.is______.
随机试题
社会保障基金的监管原则是什么?
急性坏死性肠炎肠伤寒穿孔
一个系统是稳定的,当遇到阶跃扰动时,在过渡过程结束后,被控量应趋于()。
不属于金属基复合材料的是()。
采取铺设砂垫层,塑料多孔排水板等工程措施,使软基表层或内部形成水平或垂直排水通道,加速土中水分的排除,使土固结的地基处理方法为()。
某人有1200元,拟投入报酬率为8%的投资机会,经过( )年才可使现有货币增加1倍。
通过新资源使得至少有一个人的福利水平有所提高,称为()。
《导游人员管理条例》规定,不得颁发导游证的情形主要有()。
若游客要求购买景区地摊商品,景区导游员应()。
A.particularlyB.correlatedC.averageD.peaceE.singleF.callsG.ordinaryH.engageI.notesJ.restK.shownL.exactly
最新回复
(
0
)