Weallknowthatanimalsarebetteratsomethingsthanourhumansandwecanusuallyexplainwhyanimalscandocertainthingsbetterthanus.Oneoftheskillswhichmanyanimalshaveishominginstinct(本能).Theseanimalssuchaspig

　　Weallknowthatanimalsarebetteratsomethingsthanourhumansandwecanusuallyexplainwhyanimalscandocertainthingsbetterthanus.Oneoftheskillswhichmanyanimalshaveishominginstinct(本能).Theseanimalssuchaspigeonsbeessalmons(三文鱼)frogsandcatsareabletofindtheirwayhomesometimesmakingjourneysofhundredsofkilometersbackhome.Inourdailylifehumanscanmakeuseofananimal’shominginstinct.Pigeonsforexampleshavebeenusedtocarrymessagesorletterstothebattles(战场)intimesofwar.NowadayssomepeoplejoininthePigeonAssociation(协会)withthepigeonstheyhavetrainedbecausetheylookonpigeonracingasahobbyandtheyevenbet(打赌)moneyonwhichpigeonwouldwinintheraceorganizedbytheassociation.

　　Therearemanyinterestingstoriesofthehominginstinctatwork.IntheUSAacattraveled1360kilometersbacktoitsoldhomeaftertheownersmovedtakingnearlyayearoverthejourney.Whenweloseourkitten(小猫)weusuallyfindheragainnearthehousewhereshewasborn.Wehaveapondinthegardenwherethefrogscomebackeveryyear.Ievenheardadogwhichwasinjuredbyacarmanagedtotakeitselftothevet!Thereareotherwonderfulstoriesaboutthehominginstinct.Buthowdotheseanimalsfindtheirwayhome?Theydon’thavesatellitenavigation(导航)withthemtheycan’treadmapsandasfarasweknowtheycan’taskeachotherfordirections.Itseemsthatsomeanimalssuchassalmonsusetheirsenseofsmelltotakethembacktotheplacewheretheywereborn.Otheranimalssuchasbirdsandbeesmayusethesunthestarsandthemoontohelpthemfindtheirway.Thereisatheory(理论)thatsomeanimalshavemagnetic(磁的)cellsintheirbrainwhichhelpthemtofindtheirway.AsfarascatsareconcernednobodyreallyknowshowtheirhominginstinctworksandIamsurecatsarenevergoingtogiveawaytheirsecrets.

　　Finallyajokeaboutthehominginstinct:

　　Question:Whatwillyougetifyoucross(杂交)apigeonwithaparrot?

　　Answer:Abirdwhichcanstopandaskthewayhome!

　　1.Whatdoestheunderlinedphrase“giveaway”probablymeaninthepassage?

　　A.Handout.B.Lookinto.C.Showoff.D.Letout.

　　2.WhichofthefollowingisTRUEaccordingtothepassage?

　　A.Ancientpeopleusedtomakemoneybyflyingpigeon