Challenges Of Life.docx
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Challenges Of Life.docx
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ChallengesOfLife
ChallengesOfLife
Ourplanetmaybehome
to30milliondifferentkindsofanimalsandplants.
Eachindividuallockedinitsownlife-longfightforsurvival.
Everywhereyoulook,onlandorintheocean,thereareextraordinary
examplesofthelengthslivingthingsgototostayalive.
ThisisthecoastofFlorida.
Here,strangescarsontheseabed
hintatoneanimal'sremarkablestrategy.
Thesearebottlenosedolphins,
oneofthemostintelligentanimalsonEarth.
Theirpreyisveryelusive,fast-swimmingfish.
Butthedolphinshaveinventedacompletelynewwayofhunting.
Bybeatingitstaildownhard,thisdolphinstirsuptheshallowsilt.
Andbyswimminginatightcircle
itcreatesaringofmushroomingmudaroundashoaloffish.
Thecontractingringtrapsthefishjustlikeanet.
Panicked,thefishjumptoescape.
Rightintotheopenmouthsofthewaitingdolphins.
Againandagain,theleaddolphincreatesacircle,
beforetheyalllineupwithperfecttiming.
Thesedolphinsaretheonlyonesknown
tohavedevelopedthishuntingbehaviour
anditgivesthemanedge.
Thissortofadvantage
maymeanthedifferencebetweenlifeanddeath
inthesurvivalofthefittest.
Thisseriesrevealsthemostspectacularandextraordinary
strategiesthatanimalsandplantshavedevelopedtostayalive.
Foreverycreature,everydayisfullofchallenges,
allofwhichmustbeovercome,somehow,inordertosurvive.
Kenya,famousforitsbigcats.Thesupremehunters.
Cheetahsspecialiseinhuntingatspeed.
Thoughfast,theyarefragilecreatures,builttosprintaftersmallprey.
Theydon'thavethestrengthorweightofalion
tobringdownlargeranimals.
Thismaleisdifferent.Hedoesn'thuntalone.
He'slearntthatthereisstrengthinnumbers.
Butheretherearenotjusttwo,butthreecheetahs.
Abandofbrothers.
Theyhavechangedtheirtacticsand,bydoingso,
havetakentheirpreybysurprise.
Theyhavelearntthatworkingtogether
theycanbringdownlargeprey.
Anostrich.
Abirdthattowersoveracheetahandismorethantwiceasheavy.
Itcan'tflytoescapedanger,butitcanlashoutwithadeadlykick.
Afemale,unawareasyet,ofanydanger.
Evenwiththreeofthemthisisstillhighlyrisky.
Ifonegetsinjured
theothertwocouldn'thopetotacklesuchlargeprey.
Ontheotherhand,
iftheygetitright,therewardsarehuge.
Themalehasspottedoneofthebrothers,butonlyone.
It'snottooworried.
Thensuddenlytherearethree!
Thefemaleisslowertorealisethedanger
andthecheetahsswitchtargets.
Ittakesthecombinedeffortandweightofallthreebrothers
tobringdownthispowerfulbird.
Evennowtheostrichcouldlandafatalkick.
Sofar,thebrothersarewinning.
Ostricheshaveyettofindawaytofoilsuchtactics.
Otheranimalshavealsoevolvedsurprisingtacticstooutmanoeuvre
theenemy,notwithbrutestrength
butwithextraordinaryweapons.
Madagascar.
Astrangeworldwherenothingisquiteasitseems.
Tohunthererequiresstealthandsubterfuge.
Andlivingwithinthetreesisamasterofambush.
Apreyingmantis.
Wellcamouflagedandlightningquick,
theseinsectsarehighlyefficientpredators.
Buteventheyareoutgunned.
Achameleon.
Itscamouflageisexceptional
becauseitcanchangeitsskincolourtomatchitssurroundings.
Itseyesmoveindependentlytospotprey.
Itcreepstowardstoitsvictim,untiljustinrange.
Thenitunleashesasuperweapon.
Itstongueshootsoutat15metrespersecond.
Andnotonlyhits,butgraspsitstarget.
Butfewhuntersarealwayssuccessful.
Forthemahuntisjustonemeal.
Forprey,thestakesarehigher.
It'slife...ordeath.
AsAntarcticamovesfromspringintosummer
theinletsandbays,oncechokedwithice,becomefree.
Andanimalsmoveintofeed.
Thesearecrabeaterseals.Theydon'tactuallyeatcrabs
butkrill,smallshrimpsthatswarmintheirbillionsinthesewaters.
Restingonalargeicefloe,
thesecrabeatersaresafe.
Butassoonastheyenterthewater,
theyareontheirguard,
forgoodreason.
Killerwhales.
HereinAntarctica,manykillerwhalespreyonlyonfish.
Butthesewhalesaredifferent,theyspecialiseinhuntingseals.
Thissealswimmingtoopenwater
isunawareofthedangerheadinghisway.
Untilnow.
He'sinrealtrouble.
Thereisnoescapeunlesshecanhidebehindthissmallpieceoffloatingice.
Buthe'sbeenspottedandsurrounded.
Nowagilityishisonlychance.
Hedodgesforhislife,stayingascloseashecantotheiceberg.
He'stiring.
Andthewhalestightenthecircle,goingforthekill.
Buthuntersdon'talwaysgettheirownway.
Intheend,theseal'sdeterminationandskill,using
theiceforprotection,kepthimjustoutofreach.
Andthewhalesmoveon.
Recentlyit'sbeenobservedthatkillerwhales
aremuchmoresuccessfulwhenhuntingothertypesofseal.
Crabeaterslikethisputuptoomuchofafight.
Forcreatureslivingintheopenocean
thereisnowheretohidefrompredators.
Butthereissafetyinnumbers.
Onefish,however,hasevolvedadifferentescapetactic.
Toleavethewatercompletely,taketotheairandfly!
Afterahugeefforttogetairborne,flyingfish
canglide200metresorso,
toescapethepredatorschasingthem.
Notallanimalsarehunters,manyarevegetarians.
Butthebattlebetweenanimalsandplants
canalsobeintense.
BoaVista,centralBrazil.
Thisvalleyispepperedwithstrangelypittedrocks.
Thesearenotnaturalformations
butthelegacyofalongstrugglebetweenoneanimalandoneplant.
Brown-tuftedcapuchins,highlyintelligentmonkeys.
Theyspendtheirnightsinthesafetyofcaves,
emergingeachmorningtofindfood.
Downinthevalleyisaparticularfavourite.
Anutpalm.
Thepalmsproducehugeseeds,
buttheyhaveverystrongshells
thatprotectthemagainstattackfromhungryanimals.
Forthecapuchinsthisisawarofattrition.
Theycheckwhichseedistheripest,
andthebattlecommences.
Thefirstjobistotearthetoughfibroushuskfromthenut.
Hedoesn'ttrytocrackthenutstraightaway,
butdropsittotheground.
He'slearntthatanutshouldbegivenaweekorsodryinginthesun.
Theseareoneshepreparedearlier.
Hetapsthemtoseeifthey'reready.
Thishugeflatrockishisanvil.
Andthisisahammer.
It'smadeofadifferentandmuchharderrockthantheanvil.
Nowsomethingextraordinaryhappens.
Thecapuchins'useofthesestonetoolsrequiresanexceptionallevel
ofintelligence,planninganddexterity.
Thenutfinallycracks
andexposesarich,oilykernel.
Youngsterswatchandimitatetheadults,
justashumantoddlersdo.
Iftheyaretobecomeindependent,theymustlearntocracktheirownnuts.
Butthelearningprocessislong,withmanyfrustrations.
Theylearnearlyonthattodoajobproperly,
youneedtherighttool.
Itcantakeeightyearsforacapuchintomasterthisart
andovercomethepalm'sformidabledefences.
Butsomeplantshaveturnedthetablesandfeedonanimals.
Thisisahighlysophisticatedtrap.Thebait,
sugarynectararoundtherimofthedisc.
Thetriggers,finehairs,
twoofwhichhavetobetouchedwithin20secondsofeachother.
Thevictim,afly
whichfindsthecolourandnectarirresistible.
Whentriggered,thetrapsnapsshutsofast
thattheflyisimprisoned.
TheVenusflytrapnowslowlydigestsitsvictim.
Life'schallengesaremorethanjustfindingfood.
Ineveryanimal'slifetherecomesatime
whenitsmindturnstobreeding.
Onecreature'sapproachismind-boggling.
Malaysia.
Thisstrangeinsecthasbeenlyingdormantontheforestfloor.
Oncesafeinthetrees,
thesemaleshideamongtheleaves
andbeginanextraordinarytransformation.
Onethatwillmakethedifferencebetweenfatheringoffspringornot.
Hebeginsbygulpinginairbubbles,
forcingthemupintohishead.
Hethenpumpsthebubblesintothestalkssupportinghiseyes,
justlikeblowingupaballoon.
Andthisiswhatearnsthesecreaturestheirname,
thestalk-eyedfly.
Afewfinaladjustments
tostraightenoutanyremainingcreases
andhe'sreadyforaction.
Theymaylookunwieldy,
buteyesonstalksimprovenotonlyhisabilitytospotpredators,
buttheyarekeywhenitcomestowinningfemales.
Intheeveningbothmalesandfemalesgather
andthemalesbegintosizeoneanotherup,
eyeballtoeyeball.
Havingthewidesteyespan
putsyouatthetopofthepeckingorder.
Theeyestalksarenotweapons,
they'remeasuringsticks,usedtogauge
howbig,andsohowstrong,amaleis.
Butthere'stroubleiftwotopmaleshaveexactlythesameeyewidth.
Thenthecontestdescendsintoabrawl.
Defeated.
Thewinner.
Henowhastherighttomatewithallthefemalesnearby.
Therathergentlemanlywaystalk-eyedflies
settletheirdifferencesoverfemales
isnottheonlyway.
Someanimalsaremuchmoreviolent.
It'sthedryseasoninZambia.
Thelagoonsareeitherbakeddry,
orthemudissothickanimalsgetstuck,
withfatalconsequences.
Thismalehippohasbeenlivinginonesmalllagoon,
butasitdries,it'sturningintoadeathtrap.
Understandably,thefemalesthatonceshareditwithhimhaveallleft.
Evenifhewantsto,
hecan'tstaymuchlonger.
Heneedswatertokeepcoolandfemalestomatewith.
Andthisiswheretheyallare.
Almostallthehipposinthearea
areinwhatisleftoftheLuangwaRiver,
becauseit'sthelastplacewherethere'sstilldeepwater.
Thisbendiscontrolledbyanall-powerfulmale.
Sincethedroughtmanymorefemaleshavejoinedhisherd.
Theyarehappytolivecheekbyjowl,
butanymalewhocomeshereinthehopeofmating
mustfirstdefeattheoverlord.
Thewanderingmalearrivesandhasadecisionto
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