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1、智課網(wǎng)TOEFL備考資料候鳥被迫遷徙更遠(yuǎn)一托福閱讀機(jī)經(jīng)背景Climatechangewillforcebone-wearybirdsmigratingtoEuropefromAfricatologextramileage,withpossiblydevastatingconsequences,accordingtoastudyreleasedonWednesday.Theannualvoyageofsomespecies,whichflynorthinsearchoffoodandsuitableclimes,couldincreasebyasmu
2、chas400kilometres(250miles),theresearchfound."Marathonmigrationsforsomebirdsaresettobecomeevenlonger,"saidStephenWillis,aprofessoratDurhamUniversityinBritainandthemainarchitectofthestudy."ThisisbadnewsforbirdsliketheWhitethroat,acommonfarmlandbird.Theaddeddistanceisaconsiderab
3、lethreat."Astemperaturesriseandhabitatschange,birdswillfacetheirbiggestchallengesincethePleistoceneera,whichended11,000yearsago”,hesaidinastatement.Some500millionbirdsmigrateeachyearfromAfrica,someweighingaslittleasninegrammes(three-tenthsofanounce).Tocompleteavoyagethatcanbet
4、housandsofkilometreslong,birdshavetofattenthemselvesuptotwicetheirnormalweight.Someevenshrinktheirinternalorganstobecomemorefuelefficient,soanyadditionaldistancetravelledtakesitstoll.ThestudyispublishedintheJournalofBiogeography.From2071to2100,nineoutof17speciesexaminedareproj
5、ectedtofacelongermigrations,particularlybirdsthatcrosstheSaharadesert,thestudyfound.SomebirdstraversetheSaharaandtheMediterraneanSeainaonego,whileothersmakeapit-stopinnorthernAfricabeforecrossing.Manyflyatnight,whentemperaturesarecooler.Afew--suchastheBlackcap--havestartedtoad
6、aptbyspendingwintersinBritain,butsuchbehaviourremainsexceptional,thestudysaid.ThestudyforecastthatthemigrationdistanceoftheOrpheanWarblerwilljumpfrom2,700kilometres(1,700miles)tobetween3,050and3,350kilometres(1,900and2100miles),withevenlongerincreasesfortheSubalpineandBarredWa
7、rblers本周三公布的一項(xiàng)研究顯示，氣候變化將迫使從非洲遷徙至歐洲的候鳥再多飛數(shù)百英里，對(duì)于已經(jīng)精疲力盡的鳥來說，這可能會(huì)帶來毀滅性的后果。研究發(fā)現(xiàn)，一些向北飛行以覓食和尋找合適棲息地的候鳥每年飛行的距離可增加約400公里(合250英里)。英國達(dá)翰姆大學(xué)的教授、研究骨干斯蒂芬?威利斯說：“對(duì)于一些候鳥來說，馬拉松式的遷徙路程將變得更遠(yuǎn)。”“這對(duì)白喉鶯這樣的普通農(nóng)田鳥類來說是個(gè)壞消息，多飛的行程對(duì)于它們來說是個(gè)很大的威脅?！彼谝环萋暶髦蟹Q：“隨著溫度上升，棲息地環(huán)境變化，候鳥將面臨自1.1萬年前結(jié)束的更新世(譯者注：屬于或標(biāo)志第四紀(jì)的兩個(gè)時(shí)期中較
8、早時(shí)代的地質(zhì)時(shí)期、巖石系列和沉積礦床的，這一時(shí)期以互生外貌、北方冰蝕退縮和人類祖先的出現(xiàn)為特征)時(shí)期以來最大的挑戰(zhàn)?！泵磕?/p>
