DEERANDTHEENERGYCYCLE能源复习课程

1、Good is good, but better carries it.精益求精，善益求善。DEERANDTHEENERGYCYCLE能源-Isthereanythingwecanlearnfromdeer?Duringtheenergycrisisof1973-1974thewriterofthisessaywaslivinginnorthernMinnesotaandwasabletoobservehowdeersurvivewhenwinterarrives.Thelessonshelearnsabouthewaydeerconserveenergyturnoutapplicableto

2、oureverydaylife.DEERANDTHEENERGYCYCLESomepersonssaythatlovemakestheworldgoround.Othersofalessromanticandmorepracticalturnofmindsaythatitisntlove;itsmoney.Butthetruthisthatitisenergythatmakestheworldgoround.Energyisthecurrencyoftheecologicalsystemandlifebecomespossibleonlywhenfoodisconvertedintoenerg

3、y,whichinturnisusedtoseekmorefoodtogrow,toreproduceandtosurvive.Onthiscyclealllifedepends.Itisfairlywellknownthatwildanimalssurvivefromyeartoyearbyeatingasmuchastheycanduringtimesofplenty,thesummerandfall,storingtheexcess,usuallyintheformoffat,andthenusingthesereservesoffattosurviveduringthehardtime

4、sinwinterwhenfoodisscarce.Butitisprobablylesswellknownthatevenwiththeirstoredfat,wildanimalsspendlessenergytoliveinwinterthaninsummer.Agoodcaseinpointisthewhiter-taileddeer.Likemostwildlife,deerreproduce,grow,andstorefatinthesummerandfallwhenthereisplentyofnutritiousfoodavailable.Aphysicallymaturefe

5、maledeeringoodconditionwhohasconceivedinNovemberandgivenbirthtotwofawnsduringtheendofMayorfirstpartofJune,mustsearchforfoodforthenecessaryenergynotonlytomeetherbodysneedsbutalsotoproducemilkforherfawns.Thebestmilkproductionoccursatthesametimethatnewplantgrowthisavailable.Thisisgoodtiming,becausemilk

6、productionisanenergyconsumingprocessitrequiresalotoffood.Thecostcannotbemetunlesstheregionhasamplefoodresources.Asthesummerprogressesandthefawnsgrow,theybecomelessdependentontheirmothersmilkandmoredependentongrowingplantsasfoodsources.Theadultmalesspendthesummergrowingantlersandgettingfat.Bothmalesa

7、ndfemalescontinuetoeathighqualityfoodinthefallinordertodepositbodyfatforthewinter.Inthecaseofdoesandfawns,agreatdealofenergyisexpendedeitherinmilkproductionoringrowing,andfatisnotaccumulatedasquicklyasitisinfullgrownmales.Fatreservesarelikebankaccountstobedrawnoninthewinterwhenfoodsuppliesarelimited

8、andsometimesdifficulttoreachbecauseofdeepsnow.Asfallturnsintowinter,otherchangestakeplace.Fawnslosetheirspottedcoat.Haironallthedeerbecomesdarkerandthicker.ThechangeinthehaircoatsisusuallycompletebySeptemberandmaximumhairdepthsarereachedbyNovemberorDecemberwhentheweatherbecomescold.Butinaddition,nat

9、ureprovidesafurthersafeguardtohelpdeersurvivethewinteraninternalphysiologicalresponsewhichlowerstheirmetabolism,orrateofbodilyfunctioning,andhenceslowsdowntheirexpenditureofenergy.Thedeerbecomesomewhatslowanddrowsy.Theheartratedrops.Animalsthathibernatepracticeenergyconservationtoagreaterextremethan

10、deerdo.Althoughdeerdonthibernate,theydothesamethingwiththeirseasonalrhythmsinmetabolism.Deerspendmoreenergyandstorefatinthesummerandfallwhenfoodisabundant,andspendlessenergyandusestoredfatinthewinterwhenfoodislessavailable.Whentheenergycrisisfirstcamein1973-1974,Iwaslivingwithmyfamilyinacabinontheed

11、geofanareawheredeerspendthewinterinnorthernMinnesota,observingthedeerastheirbehaviorchangedfrommoreactivityinsummerandfalltolessaswinterprogressed,followedbyanincreaseagaininthespringasthesnowmelted.Itwasinterestingandratheramusingtolistentotheadvicegivenontheradio:Driveonlywhennecessary,weweretold.

12、Putonmoreclothestostaywarm,andturnthethermostatonyourfurnacedown.Meanwhilewewatchedthedeerreducetheiractivity,growawintercoatofhair,andreducetheirmetabolismastheyhaveforthousandsofyears.Itisbiologicallyreasonablefordeertoreducetheircostoflivingtoincreasetheirchanceofsurvivinginwinter.Noteverywinteri

13、scriticalfordeerofcourse.Ifthewinterhaslightsnow,survivalandproductivitynextspringwillbehigh.Butifdeepsnowscomeandtheweatherremainscoldforseveralweeks,thenthedeermustspendmoreenergytomoveabout,foodwillbehardertofind,andtheymustthendependmoreontheirfatreservestopullthemthrough.Ifsuchconditionsgoonfor

14、toolongsomewilldie,andonlythelargestandstrongestarelikelytosurvive.Thatisafundamentalruleoflifeforwild,freewanderinganimalsuchasdeer.Yes,lifeanddeath,too-isacyclethatgoesroundandround,andwhenanimalsdietheirbodiesbecomefoodforotherlifeformstousebyconvertingthemintoenergy.Andthecyclecontinues.NewWords

15、Deern.(sing.orpl.)鹿romantica.belongingtoorsuggestingromance;fancifulnotpractical浪漫的；幻想的turnn.anaturaltendency;inclination(天生）倾向currencyn.moneythatisactuallyinuseinacountry通货，货币ecologicala.oforconcerninginterrelationshipoforganismsandtheirenvironment生态的ecologyn.生态学convertvt.change(fromoneform,use,etc

16、.intoanother);cause(aperson)tochangehisbeliefs,etc.使转变；使改变信仰（等）excessn.thepartthatismorethanenough;theconditionofexceedingwhatisusualornecessary过量；过度reserven.sth.thatisbeingorhasbeenstoredforlateruse储备（物）scarcea.notavailableinsufficientquantity缺乏的wildlifen.animalsandplantswhichliveandgrowwildnutriti

17、ousa.fullgrownanddeveloped成熟的；成年的femalea.ofthesexthatgivesbirthtoyoung女（性）的；雌的n.afemaleperson,animalorplantconceivevt.becomepregnantwith(young);form(anidea,plan,etc.)inthemind怀（胎）；构思fawnn.ayoungdeerlessthanayearoldtimingn.selectionformaximumeffectoftheprecisemomentforbeginningordoingsth.时机的选择consume

18、vt.eatordrink;use;useup消耗；消费regionn.aplace,spaceorarea;apartofthebody地区；（身体的）部位amplea.plentiful充裕的resourcen.(pl.)possessions(esp.ofacountry).intheformofwealthandgoods,thathelponetodowhatonewants资源dependenta.relying(onanother)forsupportmalea.ofthesexthatdoesnotgivebirthtoyoung男（性）的；雄的n.amaleperson,an

19、imalorplantantlern.thesolid,bonyhornofamaledeer鹿角，茸角depositvt.putorstoreforsafekeeping;(esp.ofaliquid,ariver)leavelying(alayerofmatter)存放；使沉积doen.afully-grownfemaledeerexpendvt.spendoruseup花费；耗尽accumulatev.makeorbecomegreaterinnumberorquantity;collectorgather积累；积聚accountn.asumofmoneykeptinabankwhich

20、maybeaddedtoortakenfrom帐户；存款spotteda.markedwithspotsdepthn.thestateordegreeofbeingdeep深；深度，厚度safeguardn.ameansofprotectionagainststh.unwanted预防措施internala.oforintheinside,esp.ofthebody内部的；体内的physiologicala.生理的；生理学的metabolismn.新陈代谢hencead.therefore因此，所以expendituren.expendingorusingup;theamountofmoney

21、,time,etc.expended花费；用光；支出额，费用somewhatad.bysomedegreeoramount;alittle有点，稍微drowsya.sleepyorhalfsleepy;makingonesleepy困倦的；催眠的hibernatevi.(ofsomeanimals)passthewholeofthewinterinastatelikesleep冬眠extremen.eitherendofanything;highestdegree极端seasonala.dependingontheseason;changingwiththeseasons季节性的rhythmn.节奏abundanta.morethanenough充足的；丰富的cabinn.asmallroughlybuilt,usu.woodenhouse小木屋；茅舍meltv.cause(asolid)tobecomeliquid;(ofasolid)becomeliquid（使）融化；（使）熔化amusinga.funny逗人笑的；引起乐趣的amusevt.causetolaughorsmilethermostatn.anautomati