艾斯英语听力材料.docx

艾斯英语听力材料[00:00.00]ThisisWhat’sTrendingToday...[00:03.09]Threemillionyearsmayseemlikealongtime.[00:08.25]ButwhenyouconsiderthatplanetEarthismorethan4.5billionyearsold,itisaprettyshortperiodoftime.[00:19.43]Anditisoverthatshortertimeperiodthatthewhalesinouroceanstodaygottobesolarge.[00:30.08]Thebluewhaleisthelargestanimalthathaseverlived.[00:34.80]Theyweighmorethaneventhebiggestdinosaurs.[00:40.35]Theycangrowto30meterslongandweighupto130,000kilograms.[00:49.64]Bluewhalesarepartofthebaleenwhalefamily.[00:54.17]Baleenisakindoffood-filteringstructureinthemouthsofthewhales.[01:00.51]Thewhalesdevelopedthissystemabout30millionyearsago.[01:07.09]Otherwhalesinthebaleenfamilyincludefinwhales,bowheadwhales,andrightwhales.[01:16.45]Today,thesewhalescanweighwellover70,000kilograms.[01:23.74]Butformillionsofyears,theywerenotnearlythatlarge,scientistssay.[01:31.07]“Allofasudden–‘boom’–weseethemgetverybig,likebluewhales,”scientistNickPyensontoldtheNewYorkTimes.[01:42.26]HeandotherresearchersrecentlypublishedanarticleonwhalesizeintheBritishresearchjournalProceedingsoftheRoyalSocietyB.[01:55.73]“It’slikegoingfromwhalesthesizeofminivanstolongerthantwoschoolbuses,”Pyensonadded.[02:04.32]Theresearchers--Pyenson,JeremyGoldbogenandGrahamSlater--believethatachangeintheEarth’sclimatecausedwhalestogetsolargeonlyabout3millionyearsago.[02:21.25]Thischangeledtofoodbecomingmoreeasilyavailable.[02:26.46]Anoncomingiceagemadetheoceanwatercold.[02:30.96]Highwindsmixedthewaterintheoceanfasterthanbefore.[02:36.77]Rainandsnowmademorenutrientsrunofffromthelandintothewater.[02:44.14]Thenutrientsresultedinalgae.[02:47.68]Thatattractedsmallfishandshrimpcalledkrill.[02:53.52]Themixtureofnutrientsresultedinmorefoodforlargewhalestoeat.[02:59.90]Whalesthatwereabletoquicklyeatalotoffoodsurvived.Andtheygotlarger.[03:07.11]Whalesthathadteethinsteadofbaleen,however,didnotsurvive.[03:13.65]Thelargestbaleenwhalesthenproducedotherlargewhales.[03:19.78]Overthenextthreeorfourmillionyears,thebaleenwhalesgrew10timesbigger