C★★★★☆

  Foodcanbeagreatcause.Andjustlikepeopleanimalsoftengetquitecreativewhenthey’reinthemoodforamealortreat.NowavideoshowsAsianelephantscleverlyblowairtomovefood.

  KaoriMizunoandcolleaguesworkedwithtwofemaleAsianelephantsMinekoandSuzuko.ThetwoelephantslivedinanareasurroundedbyaU-shapedditch(壕沟).Theditchwasjustshallowenoughthatanelephantcouldreachanobjectonthebottomwithitstrunk(象鼻).Butitcouldn’treachanobjectonthefarsideofthisditch.ThisletMizuno’steamsetupadifficultyfortheanimals.Theyxegularlysetouttastytreatsapplesbamboopotatoesorfallenleavesonthefarsideoftheditch.Bothelephantswerecaughtonfilmblowingtheirtrunkstodrawthefood.Eachwouldreachouthertrunkaimbackwardsabitandthenblowoutafewpuffsofair.Thatdrovethefoodsothatitwascloseenoughtocatch.MinekousedfewerpuffsblewlongerandaimedbetterthanSuzuko.

  Scientistsoncebelievedthatonlyhumansusedtools.It'sworthlookingattheelephants’behavioragain.Istrunk-blowingconsideredtooluse?Theclassicdefinitionofatoolis“theexternal(外部的)employmentofanunattachedenvironmentalobject.wAirisnotan“object”Soitmaynotqualify.Butwhatmaybemoreimportanttoconsideristhethinkingprocessesthatdrivethebehavior.

  Theresearchersareunsurehowtheelephantspickedupthistrunk-blowingbehavior.Theymighthavedoneitbyaccident.Butthefactthattwofemaleslivingtogetherarebothshowingthesamebehaviorsuggeststhatoneelephantmayhavecopiedit.Andlet’shopeso.Afterallelephanttrunk-blowingmightbeentertaining.

9.WhathasKaoriMizuno5steamfoundout?

   A.Elephantseattoomuch.

   B.Elephantscanbringfoodcloser.

  C.Elephantsarepopularwithpeople.

   D.Elephantsarebravetododangerousthings.

10.Whatwasthefunctionoftheditchintheexperiment?

   A.Toserveasachallenge.

   B.Toprotecttheelephants.

  C.Tomaketheelephantsexcited.

   D.Tomaketheelephants’habitatlarger.

11.AccordingtoParagraph3theresearch.

   A.givesthedefinitionofatool