猎杀决胜点 猎豹.docx
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猎杀决胜点 猎豹.docx
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猎杀决胜点猎豹
I,Predator:
Cheetah-獵豹
Formillionsofyears,
thefastestanimalontheplanet,
thecheetah,
hashadtheantelopeinitssights.
Butevolutionhasgiventheantelope
anarsenalofcountermeasures
soithasachancetoescape.
Inordertosurvive,
thischeetahhashadtodevelopmoreweapons
thanjustherspeed.
It’stheultimatebattleofbiomechanics,
assciencedetermineswhowins
oneofnature’sdeadliestface-offs-
seenthroughtheeyesofI,Predator.
Thecheetahandtheantelopes
arewellmatchedinthepredator/preystruggle;
becauseasfastasthecheetahis,
withherblazingtopspeed
of120kilometersperhour,
somemembersofantelopefamily,
whichincludesgazellesandimpalas,
arenearlyasfast,
hittingover95kilometersperhour.
Butspeedalonedidn’twinthismothercheetah
amuch-neededmeal.
It’sherincredibleburstofacceleration
thatmakesheroneofthemostsuccessful
predatorsinAfrica-
catchinghalftheanimalsshehunts.
Sheexplodedwithalightningquickjolt-
from0to95kilometersperhour
inlessthan3seconds.
That’sanacceleration
fasterthanajetplane.
Thesecrettoherexplosivestride
isherperfectlyengineeredspine.
About60%ofhermusclemass
ispackedontoherbackbone.
Herspineexpandsandcontracts
withsomuchforce...
itactuallyadds3quartersofameter
toherstride-
Givingherthepowertolungenearly8meters
inasinglebound.
Thegroundracespasther
at31meterspersecond,
butshestayslockedontarget.
Onceherunrivaledburstofacceleration
kickedin,theantelope’slead
isgone.
Butthischeetah’sjobisn’tdoneyet.
She’ssostreamlinedforspeed
shecan’tdeliveradeadlybite
throughtheantelopespine,
likealiondoes.
Heraerodynamicskulldoesn’tleaveroom
forstrongteethorjawmuscles.
Theonlywaythatthecheetah
canmakeakillisbygoingtothethroat
andmakingastrangulationhold.
Shesqueezestheantelope’sthroat.
Sheholdsthisthroatlock
fornearly10minutes.
Andwhileshe’sdecreasing
theantelope’soxygensupply,
she’sactuallyincreasinghers-
suckingindeepbreaths
throughherenlargednasalcavity,
tryingtorecoverfromthemassivestrain
ofa120kilometersperhoursprint.
Butshecan’taffordtorestanylonger.
Theanimalcouldweighasmuchasshedoes,
butsheneedstogetitoutofthere.
Shecan’teatitintheopen.
Shehastogetthatfoodtoasafeplace
andeatitasquickaspossible
beforeitattractstheattention
ofsomeoftheotherpredators.
Withjustherteeth,shedrags
the30-kilogramcarcass
underthecoverofatree.
Shehastoslowdownforjustabit
andcatchherbreathagain.
Shehastorestanywherefrom15minutes
tohalfanhourtofullygetdown
toanormalheartrate.
Runningfasterthananylandanimalonearth
takesamassivetollonherbody.
Shejustburnedthroughover300calories
inonechase.That’slikeahuman
runningwithoutstoppingfor30minutes.
Shediditin30seconds.
Mostcheetahswouldspendthenexthalfhour
restingandeating,
butthismothercheetah
doesn’thavethatluxury.
She’shastogetthismeal…
toherfourcubs.
ButtheAfricansavanna
isfullofotherhungrypredators.
Justassheapproacheshercubs,
alionisontoher.
Andifshecan’tkeephimaway,
she’lllosetoday’smeal.
Anyinjurytoherwouldmeandeath
forherstarvingcubs,
soshehasnochoice
buttohandoverthekill.
Allofthateffort-
thatlossofpreciousenergy-
gone,intheblinkofaneye.
50%ofthekillsthatshemakes
arestolenbylargerpredators.
Acheetahisnotequippedtofight.
Acheetahjustdoesn’tstandachance.
Losingthatantelopewasabigblow
forthecheetah.
Sheburnsatleast2,500caloriesaday,
andthissubstantialmeal-
almost5,000calories-
wouldhavegivenherenoughenergy
tokeephergoingfor2moredays.
Andnowherenergylevelisdropping.
Hersurvivalhingesuponconsumingmorecalories
thansheburns.
Onceshehits0,she’sinthedangerzone-
andstartsburningherownmuscleforfuel.
Thecheetah’sbackwithhercubs.
Butsincefemalecheetahs
arealwayssinglemothers,
she’llhavetoonceagain
leavehercubsalonetoembarkonanotherhunt.
Inthedistance,shespots
whathumanscouldneversee
withthenakedeye.
It’dbeverysimilartous
grabbingapairofhigh-poweredbinoculars,
andasyou’rescanningthelandscape,
somethingthatwillcatchyoureye
isthesamethingthat’llcatchhereye,
andthat’smovement.
Sheclosesinonpotentialprey.
Butshecan’tmakehermovetooquickly
becausewhentwoiftgefastestanimals
inAfricaengageinabattle,
thedifferencebetweenlifeanddeath
isn’tjustspeed,it’salsovision.
Thischeetah,likemostpredators,
hasevolvedwitheyes
onthefrontofherskull.
Itgivesherbinocularvision,
andthedepthperceptiontocalculateexactly
howfarawayherpreyis.
Asimportantaseyesightisforthecheetah,
it’sevenmoreimportantfortheantelope.
Antelopes,likemostprey,
haveeyesonthesidesoftheirskull.
Sowhileacheetahmayhaveafieldofvision
ofover200degrees…
Theeyesonthesidesoftheantelope’shead
givehima270-degreefieldofview.
Withatinyshiftofhisneck,
hemonitorsthefull360degrees
ofhisenvironment.
Hiseyesaresosensitivetomovement
hecandetecttheslightestmotion
ofapredator.
Nowintheantelope’slineofsight,
thecheetahfreezes.
Sheknowsifsheremainsmotionless,
she’svirtuallyinvisible.
Thetawnycolorofthecheetah
doesagreatjobofblendingher
intoherenvironment.Thespots
thatarecoveringherbody
lookverymuchlikeshadows
andhelptobreakupherpattern,
soit’sverydifficult
forsomeoftheanimalstosee.
Whatshe’sdoingiskindof
diggingherfeetin
andshe’sgettingreadyforthatpushoff.
It’slikeatrackrunner
gettingintotheblocksbeforethegunblows.
Inthiseons-oldbattleoflifeanddeath,
thecheetahhasalwayshadtheadvantage
ofspeed,butitcomeswithacatch.
Shehasalmostnoendurance.
Andonthishunt,
withoutastrongheadstart,
shegotcaughtupinalongchase-
redliningherbody’spowerfulengine.
Shetakes150breathsaminute,
threetimesasmanyasthefastest
humansprinter.Hermassiveheart
pumpsover16litersofbloodperminute-
circulatingherentirebody’sbloodsupply
inlessthan20seconds.
Atthispace,shehaslessthanhalfaminute
beforeherbodygivesintothestress.
Herheartblasts39-degreeblood
intoherbrain.
Another1andahalfdegreeshigher
anditoverheats.
Sheonlyhassecondstomakethiskill,
orthechase…couldkillher.
Oncethebodystartstogointooverdrive
andoverheat…thebrainisthemostvulnerable
ofallbodyparts.
Oncethebrainoverheats,
there’salmostnobringingitback.
Buttheantelopeisinlessdanger
ofoverheating
becausehehasabuiltincoolingsystem.
Beforebloodreacheshisbrain,
itpassesthroughaclusterofbloodvessels
thatarecooledbyrapidburstsofair
shootingthroughhisenlargednasalcavity.
Justlikeacar’sradiator,
itpreventsvitalfluidsfromoverheating.
Andevenashisbodytemperature
reachesascorching42degrees,
hisbrainisprotected
andhecanstaycoolerunderpressure.
Whenthecheetah’stemperature
hit40degrees,herbodytoldher
shehadmeresecondstodecide
whethertolettheantelopegetaway
ordietryingtocatchit.
Foracheetah,iftheystarttheirhunt
tooearly,theycanburnthemselvesout
veryquicklyandnotbeable
tocatchtheirprey.
Shegaveiteverythingshehad,
butthehuntendedindisaster.
Anantelopecanruncloseto50milesanhour.
You’rethinking,“Okay,well,
acheetahcanrunfasterthanthat.”
Butanantelopecanmaintainthatspeed
foravery,verylongtime.
They’remorelikeendurancerunners
thatcanrunvery,veryfast,
whereasthecheetahsarejustsprinters.
Notonlydidshefailtocomeaway
withameal,herenergyreserves
tookahugehit.
Andonhernextcouplehunts,itgetsworse.
First,shespringsafteralonemale
andclosesinahurry.
Butwhatseemslikeaneasytarget
suddenlybecomesatoughkill.
Insteadofrunningaway,
theantelopebouncesupanddown.
It’sacountermeasurecalledstotting-
alastditchefforttointimidatethecheetah
byprojectingstrengthandstamina.
Anditworks.
Herinitialsprinthasalreadytakenalot
outofherandshecan’tafford
toburnanymoreenergyonakill
she’snotcertainshecanmake.
Itgetsevenmorechallenging
onhernexthunt-
asshecreepstowithin45meters
ofaherdofantelope…
buttheysprintaway,
burstingintogravity-defyingleaps.
Shooting3metersintotheair-
inandoutofthecheetah’slineofsight-
istoodisorienting
andshegivesupthechase-
butnotwithoutdepletingherenergyreserves
evenfurther.
It’sbeenaroughcoupleofdaysforher.
Sheandhercubshavegonewithoutanyfood
andthingsarestartingtolookdesperate.
Physically,thecheetahcanprobably
lastaboutaslongasyouorI
couldlastwithoutfood-
probably5or6dayswithouteating
beforesheabsolutelycollapsesofstarvation.
She’sconstantlylookingforpredators
thatcouldcomeafterhercubs,
she’slookingforprey
thatshecouldbehunting-
whichmeansthatshedoesn’thave
alotofdowntime.She’salwayson.
Thatadrenalinethat’swithinthemconstantly
iskeepingthemonguard.
It’slikebeingatwar,
whereyou’reneverabletorelax.
Shehastofindfood,andfinditfast.
Sheapproacheshernexthunt
likeacovertoperation,
targetingaherdwithseveraljuveniles-
whoareslowerandlessalert.
Thecloserthatshecangettothem
beforesheactuallystartsrunning,
the
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- 猎杀决胜点 猎豹 猎杀 决胜