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1、WrittenbyRadDaneshThursday,17May2007Readthepassageandanswerthequestions.Useyourpredictingskills.Notethetypeofquestions.AntarcticPenguinsThoughpenguinsareassumedtobenativetotheSouthPole,onlyfouroftheseventeenspecieshaveevolvedthesurvivaladaptationsnecessarytoliveandbreedintheAnta
2、rcticyearround.ThephysicalfeaturesoftheAdelie,Chinstrap,Gentoo,andEmperorpenguinsequipthemtowithstandtheharshestlivingconditionsintheworld.Besidesthesefourspecies,thereareanumberofothers,includingtheyellowfeatheredMacaronipenguinandtheKingpenguinthatvisittheAntarcticregularlybut
3、migratetowarmerwaterstobreed.PenguinsthatliveinAntarcticayearroundhaveathermoregulationsystemandasurvivalsensethatallowsthemtolivecomfortablybothontheiceandinthewater.Inthedarkdaysofwinter,whentheAntarcticseesvirtuallynosunlight,thepenguinsthatremainontheicesheetsleepmostoftheda
4、y.Toretainheat,penguinshuddleincommunitiesofupto6,000oftheirownspecies.Whenit'stimetocreateanest,mostpenguinsbuildupapileofrocksontopoftheicetoplacetheireggs.TheEmperorpenguin,however,doesn'tbotherwithanestatall.ThefemaleEmperorlaysjustoneeggandgivesittothemaletoprotectwhilesheg
5、oesoffforweekstofeed.Themalebalancestheeggontopofhisfeet,coveringitwithasmallfoldofskincalledabroodpatch.Inthehuddle,themalepenguinsrotateregularlysothatnoneofthepenguinshavetostayontheoutsideofthecircleexposedtothewindandcoldforlongperiodsoftime.Whenit'stimetotakeaturnontheoute
6、redgeofthepack,thepenguinstucktheirfeathersinandshiver.Themovementprovidesenoughwarmthuntiltheycanheadbackintotheinnercoreandrestinthewarmth.Inordertoreducethecoldoftheice,penguinsoftenputtheirweightontheirheelsandtails.Antarcticpenguinsalsohavecomplexnasalpassagesthatprevent80p
7、ercentoftheirheatfromleavingthebody.Whenthesunisout,theblackdorsalplumageattractsitsraysandpenguinscanstaywarmenoughtowaddleorslideaboutalone.Antarcticpenguinsspendabout75percentoftheirlivesinthewater.Anumberofsurvivaladaptationsallowthemtoswimthroughwaterascoldas-2degreesCelsiu
8、s.Inordertostaywarminthesetemperatures,penguins