Planet Earth II02.docx
- 文档编号:4043462
- 上传时间:2023-05-06
- 格式:DOCX
- 页数:14
- 大小:27.70KB
Planet Earth II02.docx
《Planet Earth II02.docx》由会员分享,可在线阅读,更多相关《Planet Earth II02.docx(14页珍藏版)》请在冰点文库上搜索。
PlanetEarthII02
Thereareonlyfourteenpeaksintheworldthatrisetoover8000meters.
Allofthemarehere,intheHimalayas.
Lethallycold,scouredbygalesandblizzards,thesemountainsareamongthemosthostileplacesonEarth.
Yet,afewspecialanimalsmanagetolivehere.
Snowleopards.
Likeallcreaturesofthehighmountains,theyhavehadtoadaptboththeirbodyandtheirbehaviourinordertosurvive.
Lifeatextremealtitudehasshapedsomeofthetoughestanimalsontheplanet.
Thesun-bakedmountainsoftheArabianPeninsula.
TheymayonlybeafractionoftheheightoftheHimalayas,buttheyarestillsodizzyinglysteepthatinmanyplacesit'salmostimpossibletogetafoothold.
YetNubianibexhavemadethistheirhome.
Theibexchoosethesteepestcliffstoraisetheiryoung,insafety,beyondthereachofpredators.
Butlivinginthissanctuarycomeswithacost.
Thesenurseryslopesaresosteep,thereisalmostnostandingwateruphere.
Sotodrink,anibexfamilymustdescendintothevalley...1,000feetbelow.
Themotherspickoutthesafestwaydown.
Withsoftclovenhoovesthatgripbetterthananyclimbingshoe,theyarethemostaccomplishedmountaineers.
Butthenewbornkidsarestillhavingtofindtheirfeet.
Thisistheirfirstdescent.
Onemistakecouldmakeittheirlast.
Followingtheadults,thekidsfinallyreachthevalley.
Butonceonlevelground,they'revulnerable.
Redfoxeslieinwait.
Atthefirstsignofdanger,theyoungibexinstinctivelyrunbacktosteeperground.
Butheadingforthisparticularrockyoutcropcouldbeamistake.
It'sa30-footdrop.
Thefoxhasthemtrapped...orsoitseems.
Thisiswhatibexwereborntodo.
Scatteringmakesithardforthefoxtopickatarget.
Anditcertainlycan'tfollowthemuphere.
Allitcandoiswaitforonetoslipandfall.
Buttheseyoungstersarefastlearners,andthey'renowalmostassure-footedastheirparents.
Thefoxwillhavetofinditsmealelsewhere.
It'sjustnotbeenagoodday.
Now,atlast,theyoungibexcandrink.
Butthey'llsoonneedtoreturntothesafetyofthesheercliffs.
Masteringprecipitousterrainisalwayschallenging,buttherearemorefundamentalproblemsforlifeinthemountains.
TheAlps.Europe'shighestpeaks.
It'swinter,andfoodisdesperatelyshort.
Agoldeneaglehastospendeverydaylighthourscanningtheslopesforsomething,somewhere,toeat.
Herseven-footwingspanallowshertoglideeffortlesslyfor100milesinasingleday.
Herextraordinaryeyesenablehertospotpreyfromtwomilesaway.
Butsheisnottheonlyonewho'slookingforfood.
Whenshespotsachance,shemustmovefast.
Shecandiveat200milesanhour.
Onlyaperegrineisfaster.
Duringwinter,eveneaglesrelyalmostentirelyoncarrion.
It'sadeadfox,anditcouldsustainherfordays.
Otherscavengersmustdefer.
Thehungrycrowssoonregaintheircourage.
They'lltryanytricktostealamorsel.
Andtheyareannoyinglypersistent.
Butthismobaretheleastofherworries.
Abiggereagletakescontrol.
Butthiskillistooimportanttogiveup.
Soshemustfight.
Forthemoment,she'swonthecarcassback.
Butakilllikethiswillattracteveryeagleformilesaround.
Asever,thestrongestwinsthelion'sshare.
Unabletodefendthecarcassanylonger,thefirsteaglemustnowcontinueitssearch.
Itmaybemanydaysbeforeshefeedsagain.
Onlythemostcompetitivewillsurvivetheperilsofthemountainwinter.
Anavalanche.
100,000tonnesofsnowtravellingat80milesanhour,capableofsmashingeverythinginitspath.
ThemountainsofNorthAmericaarehitbythousandsofavalancheseveryyear.
Yetoneanimalspendsthewholewinterslumberingwithinthesnowontheseavalanche-proneslopes.
Andwhenspringcomes,theyemerge.
Allacrossthesemountains,grizzlybearsmaketheirwinterdens10,000feetupinthedeepsnowofleewardslopes.
Andwhiletheywerehalf-asleepinthedepthsofwinter,theiryoungwereborn.
Nowthesecubsaretakingtheirfirststepsintotheoutsideworld.
Thismotherisleadingherthreeyoungsterstoaplacewheretheycanfindfood.
Theyneedtodescendasquicklyaspossible.
Thedebrisfromanavalancheisclearevidencethatthisslopeisstilldangerouslyunstable.
Thisisnotaplacetodawdle.
Andtheyhaveanotherreasontokeepmoving.
Afterfivemonthsintheden,thesebearsareveryhungry.
Bearsthathavehibernatedthroughoutthesepeaksnowalldescendtothevalleys,wherespringcomesearliest.
IntheRockies,seasonalchangeisswiftanddramatic.
Injustafewdays,theslopesturnfromwhitetogreen.
Meadowsthatonlyafewweeksagowereburiedbeneaththesnowarenowfulloflife.
Butinthesemountains,thegoodtimeswillnotlastlong.
Sothebearsmustfeedasfastastheycan.
Duringthesummermonths,anadultcanputon180kilosgorgingonplantsand,iftheycancatchthem...amarmotortwo.
Butjustnow,thebearshavesomethingelseontheirminds.
It'sbecomingwarmer,andthebearsarekeentoshedtheirthickwintercoats.
Mothersshowthecubswhattodoaboutthis.
They'llsooncatchon.
Sometrees,itseems,areparticularlysuitableforrubbing.
Bearshavetheirfavouritesandwilltravellongdistancestovisitthem.
Someitchesjusthavetobescratched.
Therearenowaround30bearsinthisonevalley.
Astheyrub,eachleavesanindividualandrecognizablescent.
Sothetreesooncarriesalistofwho'saround,whichmighthelpindividualstoavoidafight.
Tobestspreadtheirscent,theyreallyhavetoputtheirbackintoit.
Butsummerisshort.
Itchessatisfactorilyscratched,it'stimetoeat.
Inacoupleofmonths,theywillhavetoreturntotheirdenstohibernate,sonowtheymustputonasmuchweightastheycan.
Winterinthemountainsreturnsfastandhitshard.
TemperaturesintheRockieswilldropto-54degrees,socoldthatmoistureintheairfreezesintotinycrystalscalleddiamonddust.
Thisbobcatisoneofthefewhunterstoremainactiveinwinter.
Mostofhispreyisnowhiddenbeneaththesnowthatcovershisentireterritory.
Hehuntsbylisteningforthefaintestsoundofmovement.
Andtopreventcrunchingfootstepsfromrevealinghispresence,heusesbouldersassteppingstones.
Amouse.
Butoneisnotenough.
Thedeeperthesnow,theharderitistodetectprey,andtherewardsfortheeffortcanbedisappointing.
Tosaytheleast.
Bymidwinter,thesnowissodeepthatbobcatsareforcedtoleavetheirterritoriestotryandfindeasierhunting.
Andthisbobcatmaybeinluck.
Forthisparticularvalleyisblessed.
Ariverhereneverfreezes.
It'sfedbyavolcanichotspringthatheatsthesewatersto50degreeswarmerthanthesurroundingair.
Hungryanimalsofallkindscomeheretofeed.
Throughoutthewinter,theriverisfulloffoodforthosewhoknowhowtocatchit.
Here,eventhecoyoteshavebecomefishermen.
Buthuntingishardforacatthat'snotusedtogettingitsfeetwet.
Sohemustchoosehistargetwithcare.
Golden-eyeducks.
Butcanhegetcloseenoughtopounce?
Perhapshe'llhavemoreluckontheotherside.
Here,steamfromtheriverwarmsthesurroundingtrees,soupinthebranches,therecouldbeprey.
Ifonlyhecouldgettoit.
It's20feetup.
Atlast...asquirrel.
Notmuch,butenoughtokeephimgoing.
Tosurviveawinterinthesemountainstakestenacity,andbobcatshavethatinabundance.
Theyallthriveinthetropicalsun.
Afterall,everydayissummer.
Butoncethesunsets,everynightbecomesasbitterlycoldaswinter.
Snowontheequator.
UnliketheRockies,inthesemountainstherearenomarkedseasons.
ThisisAfrica'sMountKenya.
It's17,000feethigh,whichmakesitssummitsome30degreescolderthanthesurroundingsavanna.
Giantheathers,lobeliasandgroundselgrowonitsupperslopes.
Thetemperaturedropstofivedegreesbelowfreezing,turningthemountainsideintoagardenofice.
Everythingfreezes,butthecabbagegroundselshaveawayofprotectingthemselves.
Theycloseuptheirleatheryleavestoformaninsulatingblanketthatshieldstheirvulnerablecentralbud.
Nightcomestoanend...andthesunshinereturns.
Thegroundselsspreadtheirleaveswidetobaskinthesunshineonceagain.
DawnintheHighAndes.
Heretoo,therisingsunbringsrapidrelieftoanimalslivingamongstthesevolcanicpeaks.
Mountainviscachaareupearlytoclaimthebestplacestocatchthesun'sfirstrays.
Forothersuphere,thesunriseisevenmorewelcome.
Atover14,000feet,thisisthehighestflamingocolonyintheworld.
Atnight,itgetssocoldthateventhissaltywaterfreezesover.
Andnowtheflamingosaretrappedintheice.
Eventually,thesunthinstheice,butit'sstillastrugglefortheflamingostobreakfree.
Walkingonthiniceisalwaysrisky.
Andit'shardtoretainone'sdignity...especiallywhenyou'rewearingstilts.
Atthesealtitudes,thesun'spowercanquicklyturnfromsalvationtothreat.
Theatmosphereissothin,thereisverylittleprotectionfromultravioletradiation.
Bymid-morning,it'sriskytolingeroutintheopen.
Theviscachaareforcedtoheadfortheshade.
Outonthelake,thereisnowheretohide.
Thewhitecrustofthesodalakereflectsthesun'sglareandincreasestheimpactofitsultravioletrays.
Bymidday,uncoveredhumanskinwillburninfourminutes.
Butthisdoesn'tseemtobothertheflamingos.
Infact,theyareonparade.
Duringthebreedingseason,theflamingosperformthesepeculiarcourtshipdanceseventhroughthehottesttimeoftheday.
Theyaresoeager,theydon'tevenpausetofeed.
Therulesaresomethingofamysterybut,afteramonth
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- Planet Earth II 02