比如:老虎的习性,外形,喜欢什么讨厌什么..................不要太长的 tiger
thetiger(pantheratigris)isamemberofthefelidaefamily;thelargestofthefour"bigcats"inthegenuspanthera.[4]nativetomuchofeasternandsouthernasia,thetigerisanapexpredatorandanobligatecarnivore.reachingupto3.3metres(11ft)intotallengthandweighingupto300kilograms(660pounds),thelargertigersubspeciesarecomparableinsizetothebiggestextinctfelids.[5][6]asidefromtheirgreatbulkandpower,theirmostrecognizablefeatureisthepatternofdarkverticalstripesthatoverlaysnear-whitetoreddish-orangefur,withlighterunderparts.themostnumeroustigersubspeciesisthebengaltigerwhilethelargestsubspeciesisthesiberiantiger.
highlyadaptable,tigersrangefromthesiberiantaiga,toopengrasslands,totropicalmangroveswamps.theyareterritorialandgenerallysolitaryanimals,oftenrequiringlargecontiguousareasofhabitatthatsupporttheirpreydemands.this,coupledwiththefactthattheyareendemictosomeofthemoredenselypopulatedplacesonearth,hascausedsignificantconflictswithhumans.oftheninesubspeciesofmoderntiger,threeareextinctandtheremainingsixareclassifiedasendangered,somecriticallyso.theprimarydirectcausesarehabitatdestructionandfragmentation,andhunting.theirhistoricalrange,whichoncereachedfrommesopotamiaandthecaucasusthroughmostofsouthandeastasia,hasbeenradicallyreduced.whileallsurvivingspeciesareunderformalprotection,poaching,habitatdestructionandinbreedingdepressioncontinuetobethreats.
nonetheless,tigersareamongthemostrecognizableandpopularoftheworld'scharismaticmegafauna.theyhavefeaturedprominentlyinancientmythologyandfolklore,andcontinuetobedepictedinmodernfilmsandliterature.tigersappearonmanyflagsandcoatsofarms,asmascotsforsportingteams,andasthenationalanimalofseveralasiannations.
physicalcharacteristics,taxonomyandevolution
theoldestremainsofatiger-likecat,calledpantherapalaeosinensis,havebeenfoundinchinaandjava.thisspecieslivedabout2millionyearsago,atthebeginningofthepleistocene,andwassmallerthanamoderntiger.theearliestfossilsoftruetigersareknownfromjava,andarebetween1.6and1.8millionyearsold.distinctfossilsfromtheearlyandmiddlepleistocenewerealsodiscoveredindepositsfromchina,andsumatra.asubspeciescalledthetriniltiger(pantheratigristrinilensis)livedabout1.2millionyearsagoandisknownfossilsfoundattrinilinjava.[12]
tigersfirstreachedindiaandnorthernasiainthelatepleistocene,reachingeasternberingia(butnottheamericancontinent),japan,andsakhalin.fossilsfoundinjapanindicatethatthelocaltigerswere,likethesurvivingislandsubspecies,smallerthanthemainlandforms.thismaybeduetothephenomenoninwhichbodysizeisrelatedtoenvironmentalspace(seeinsulardwarfism),orperhapstheavailabilityofprey.untiltheholocene,tigersalsolivedinborneo,aswellasontheislandofpalawaninthephilippines.[13]
physicalcharacteristics
siberiantigertigersareperhapsthemostrecognisableofallthecats(withthepossibleexceptionofthelion).theytypicallyhaverusty-reddishtobrown-rustycoats,awhitishmedialandventralarea,awhite"fringe"thatsurroundstheface,andstripesthatvaryfrombrownorgraytopureblack.theformanddensityofstripesdiffersbetweensubspecies(aswellasthegroundcolorationofthefur;forinstance,siberiantigersareusuallypalerthanothertigersubspecies),butmosttigershaveover100stripes.thepatternofstripesisuniquetoeachanimal,andthuscouldpotentiallybeusedtoidentifyindividuals,muchinthesamewaythatfingerprintsareusedtoidentifypeople.thisisnot,however,apreferredmethodofidentification,duetothedifficultyofrecordingthestripepatternofawildtiger.itseemslikelythatthefunctionofstripesiscamouflage,servingtohelptigersconcealthemselvesamongstthedappledshadowsandlonggrassoftheirenvironmentastheystalktheirprey.thestripepatternisfoundonatiger'sskinandifshaved,itsdistinctivecamouflagepatternwouldbepreserved.likeotherbigcats,tigershaveawhitespotonthebacksoftheirears.
skeletontigershavetheadditionaldistinctionofbeingtheheaviestcatsfoundinthewild.[14]theyalsohavepowerfullybuiltlegsandshoulders,withtheresultthatthey,likelions,havetheabilitytopulldownpreysubstantiallyheavierthanthemselves.however,thesubspeciesdiffermarkedlyinsize,tendingtoincreaseproportionallywithlatitude,aspredictedbybergmann'srule.thus,largemalesiberiantigers(pantheratigrisaltaica)canreachatotallengthof3.5m"overcurves"(3.3m."betweenpegs")andaweightof306kilograms,[15]whichisconsiderablylargerthanthesizesreachedbyisland-dwellingtigerssuchasthesumatran,thesmallestlivingsubspecieswithabodyweightofonly75–140kg.[15]tigressesaresmallerthanthemalesineachsubspecies,althoughthesizedifferencebetweenmaleandfemaletigerstendstobemorepronouncedinthelargersubspeciesoftiger,withmalesweighingupto1.7timesasmuchasthefemales.[16]inaddition,maletigershavewiderforepawpadsthanfemales.thisdifferenceisoftenusedbybiologistsindeterminingthegenderoftigerswhenobservingtheirtracks.[17]theskullofthetigerisverysimilartothatofthelion,thoughthefrontalregionisusuallynotasdepressedorflattened,withaslightlylongerpostorbitalregion.thelion'sskullhasbroadernasalopenings.however,duetotheamountofskullvariationinthetwospecies,usually,onlythestructureofthelowerjawcanbeusedasareliableindicatorofspecies.[18]
biologyandbehaviour
territorialbehavior
tigersareessentiallysolitaryandterritorialanimals.thesizeofatiger'shomerangemainlydependsonpreyabundance,and,inthecaseofmaletigers,onaccesstofemales.atigressmayhaveaterritoryof20squarekilometreswhiletheterritoriesofmalesaremuchlarger,covering60–100km2.therangesofmalestendtooverlapthoseofseveralfemales.
tigersforthemostpartaresolitaryanimals.therelationshipsbetweenindividualscanbequitecomplex,anditappearsthatthereisnoset"rule"thattigersfollowwithregardstoterritorialrightsandinfringingterritories.forinstance,althoughforthemostparttigersavoideachother,bothmaleandfemaletigershavebeendocumentedsharingkills.forinstance,georgeschallerobservedamaletigershareakillwithtwofemalesandfourcubs.femalesareoftenreluctanttoletmalesneartheircubs,butschallersawthatthesefemalesmadenoefforttoprotectorkeeptheircubsfromthemale,suggestingthatthemalemighthavebeenthefatherofthecubs.incontrasttomalelions,maletigerswillallowthefemalesandcubstofeedonthekillfirst.furthermore,tigersseemtobehaverelativelyamicablywhensharingkills,incontrasttolions,whichtendtosquabbleandfight.unrelatedtigershavealsobeenobservedfeedingonpreytogether.thefollowingquotationisfromstephenmills'booktiger,ashedescribesaneventwitnessedbyvalmikthaparandfatehsinghrathoreinranthambhore:[51]
adominanttigresstheycalledpadminikilleda250kg(550-lb)malenilgai-averylargeantelope.theyfoundheratthekilljustafterdawnwithherthree14-month-oldcubsandtheywatcheduninterruptedforthenexttenhours.duringthisperiodthefamilywasjoinedbytwoadultfemalesandoneadultmale-alloffspringfrompadmini'spreviouslittersandbytwounrelatedtigers,onefemaletheotherunidentified.bythreeo'clocktherewerenofewerthanninetigersroundthekill.
whenyoungfemaletigersfirstestablishaterritory,theytendtodosofairlyclosetotheirmother'sarea.theoverlapbetweenthefemaleandhermother'sterritorytendstowanewithincreasingtime.males,however,wanderfurtherthantheirfemalecounterparts,andsetoutatayoungeragetomarkouttheirownarea.ayoungmalewillacquireterritoryeitherbyseekingoutarangedevoidofothermaletigers,orbylivingasatransientinanothermale'sterritory,untilheisoldandstrongenoughtochallengetheresidentmale.thehighestmortalityrate(30-35%peryear)amongstadulttigersoccursforyoungmaletigerswhohavejustlefttheirnatalarea,seekingoutterritoriesoftheirown.
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