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Thiswebsitewouldliketoremindyou:Yourbrowser(AppleSafari4)isoutofdate.Updateyourbrowserformore security,comfortandthebestexperienceonthissite. × Illustration MEDIASPOTLIGHT MaunaKea Theworld’stallestmountain Forthecompleteillustrationswithmediaresources,visit: http://education.nationalgeographic.com/media/mauna-kea/ TheillustrationaboveisfromthesupplementtotheSeptember2012issueofNationalGeographicmagazine. Downloadthefileandopentoviewinfull. HawaiiistheyoungestandlargestofachainofislandsmakinguptheHawaiianarchipelago.Thearchipelagois composedofeightmainislandsandseveralsmallerislandsandatolls,whichwereonceactivevolcanoesthathave sincesunkanderodedovermillionsofyears.TheHawaiianarchipelagoformsbecauseofthepresenceofahot spotmorethan1,448kilometers(900miles)deepintheEarth’scrust.AsthePacifictectonicplatemoves northwestoverthehotspot—atarateofabout7.6centimeters(3inches)peryear—magmafromthehotspot breaksthroughtheplate’scrusttoformvolcaniclandmasses.AsthePacificplatemovesfromthesoutheasttothe northwest,theolderislandsgetfartherfromthehotspotandbeginaprocessofsinkinganderoding.Niihau,the mostnorthwesterlyofthemainHawaiianIslands,isabout6millionyearsold.Hawaii,theyoungestofthemain islands,remainsclosetothehotspot,andatlessthan1millionyearsold,itisstillformingasthehotspotfeeds lavatoitsactiveKilaueavolcano. MaunaKea,oneofsixvolcanoesthathaveformedtheislandofHawaii,isthetallestmountainonEarthat9,966 meters(32,696feet,6.2miles).Thisis1,116meters(3,661feet,0.7miles)tallerthanMountEverestandroughly thesameheightintheatmospherewherecommercialairplanesfly.With4,205meters(13,796feet,2.6miles) abovesealevel,morethanhalfofMaunaKea’sheightfallsbelowthesurfaceoftheocean,withitsbasereaching 5,761meters(18,900feet,3.6miles)deep.MaunaKeaisdormant,havinglasterupted4,600yearsago.Kohalais theisland’soldestvolcanoandisnowextinct.Hualalailasteruptedin1801,andMaunaLoalasteruptedin1984. Kilaueahasbeeneruptingactivelysince1983. ThegeologiclandscapeofHawaii’sislandshaschangedgreatlyovertime,whichhasalsoimpacteditsecologic landscape.AsHawaii’svolcanicislandsriseandfall,organismsmustadapttoaseriesoftransitionalhabitatsboth aboveandbelowtheoceansurface.IntermsofthehabitatsandspeciesthatarepartofMaunaKea—fromits mountainpeaktoitsoceandeep—thecolossalmountainisnotonlytall,buthighinbiodiversityaswell.Mauna Kea’svarietyofterrestrialhabitatsincludesstonedeserts,shrublands,alpinewoodlands,andtropicalforests. ThesevariedhabitatsarehometoseveralendemicspeciesthatareonlyfoundonHawaiiortheHawaiian archipelago.TheoceanhabitatsthatcharacterizeMaunaKeaareequallyvariedandfulloflife.Thegreatest quantityofmarinelifeisfoundbetweenthesurfaceandadepthof1,189meters(3,900feet,0.7miles)inthe sunlightzoneandtwilightrealm.Below3,900feetarethemidnightzoneandabyss,whicharedark,cold,under highpressures,andlackinginfood.Speciesintheseextremeenvironmentshavedevelopeduniqueadaptationsto regulatetheirtemperatures,protectthemselves,helpthemlocatefood,communicate,andfindmates. FASTFACTS 1of3 TwentymilessoutheastofHawaiiistheLoihiseamount,anactiveunderwatervolcanothatispredictedtoriseabovethe oceansurfaceinthenext50,000years.ThatmeansitcouldbecometheninthmainHawaiianisland. DuetoitsremotelocationinthePacific,MaunaKeaisfreefromtheartificiallightthatiscommoninhighlypopulated areas.Combinedwithitselevationof4,205meters(13,796feet,2.6miles),thesummitofMaunaKeaistheideallocation fortheinternationalastronomicalobservatoryandthe13internationaltelescopeslocatedthere. UnlikethehotspotthatformedMaunaKea,MountEverestformedastheresultofaconvergenttectonicboundary.As twocontinentalplatescametogether,thecrustbuckledandpushedupward,creatingtheHimalayanmountainrange.As theIndianandEurasianplatescontinuetocollide,theelevationofMountEverestincreasesby1-3centimeterseach year. VOCABULARY Term PartofSpeech Definition adaptation noun amodificationofanorganismoritspartsthatmakesitmorefitforexistence.An adaptationispassedfromgenerationtogeneration. archipelago noun agroupofcloselyscatteredislandsinalargebodyofwater. atoll noun acoralreeforstringofcoralislandsthatsurroundsalagoon. biodiversity noun allthedifferentkindsoflivingorganismswithinagivenarea. endemic adjective nativetoaspecificgeographicspace. geology noun studyofthephysicalhistoryoftheEarth,itscomposition,itsstructure,andthe processesthatformandchangeit. habitat noun environmentwhereanorganismlivesthroughouttheyearorforshorterperiodsof time. hotspot noun intenselyhotregiondeepwithintheEarththatrisestojustunderneaththesurface. Somehotspotsproducevolcanoes. oceanography noun studyoftheocean. plate tectonics noun movementandinteractionoftheEarth'splates. seamount noun underwatermountain. volcano noun anopeningintheEarth'scrust,throughwhichlava,ash,andgaseserupt,andalso theconebuiltbyeruptions. ForFurtherExploration InstructionalContent NationalGeographic:DeepSeaEcosystems—ExtremeLiving NationalGeographic:UnderseaGeology NationalGeographic:TypesofVolcanicEruptions Video NationalGeographic:AlienDeepGeology—ExploringHawaii’sUnderwaterHotspots Websites NationalGeographicChannel:AlienDeep NOAA:EducationResources—OceanandCoasts:OceanFloorFeatures 2of3 Funder ThismaterialisbasedinpartuponworksupportedbytheNationalScienceFoundationunderGrant No.DRL-1114251.Anyopinions,findings,andconclusionsorrecommendationsexpressedinthis materialarethoseoftheauthoranddonotnecessarilyreflecttheviewsoftheNationalScience Foundation. ©1996–2015NationalGeographicSociety.Allrightsreserved. 3of3