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MarineMammals&BirdsReturntotheOceansMammalshavereturnedtotheoceansmultipletimesAdaptations•vivipary•sucklingyoung•thermoregulation•feeding•diving•osmoregulationWe’lllookatadaptationinmarinemammalsfromtheleasttothemostAdaptationsfordiving•Exchangealargeamountofaironeachbreath•Upto90%ineachbreath(humansexchangeabout20%)•Bloodwithmoreoxygencarryingcapacity•Heartrateslows•Bloodflowshunted•Higherconcentrationofmyoglobininthemuscles•Collapsinglungs•DivewithnoairincontactwithbloodvesselstoavoidproblemsofnitrogenbeingforcedinFusiformShapeandStreamliningEvolutionaryConvergenceTwobasicbioenergeticstrategiesusedbyanimals:•Endothermy“warmblooded”•Ectothermy“coldblooded”CountercurrentExchangeConcurrentexchangeCountercurrentexchangeMarineBirdsSaltExcretioninBirdsPenguins:•17speciesfoundinsouthernhemisphere•Spends75%oflifetimeinwaterPenguinAdaptations:•Heavy,solidbonesfordiving•Watertightfeathers(upto70persq.in.)•Blubberforinsulation•Oilglandforcoatingfeathers•Black&whitecountershading•Deepdivers-500m,15min.•Paddle-likefeet•Streamline,fusiformbody-15mph•SocialNestingNestsonpackiceMarineMammalsMarinemammals•Characteristicsofmarinemammals:–Warm-blooded–Breatheair–Havehair(orfur)–Bearliveyoung–FemaleshavemammaryglandsthatproducemilkfortheiryoungMarinemammals:OrderSirenia•Sireniancharacteristics:–Largebodysize–Sparsehairalloverbody–Vegetarians–Toenails(onmanateesonly)•Includes:–Manatees–DugongsManatee&Dugong•Mostcompletetransitiontomarinelifealongwithwhalesanddolphins•Relatedtotheelephant,butcommonancestordidn’tlooklikeeitherofthem•Oncemanymorespeciesaround•Largelayerofblubber•Originofthemermaidmyth•Herbivores•Nostrilsontopofsnouthavevalvestokeepwaterout•Bothspecieshaveonecalfatatime•Tendtohaveasinglecalfevery3yearsLocation:coastalandinlandwatersofthewesternIndo-Pacificregion•Dugongsareexclusivelymarineandhaveadolphin-liketail•Dugongstendtodigseagrassrhizomes•PredatorincludestigersharksDugongDugongRange10,000FamilyDugongidaeDugongdugongSteller'sSeaCowtHydrodamalisgigasDiscovered1741,extinct1768.8.9ft,551-661lbs30ft,4.4tonsLocation:Florida,CentralandSouthAmerica•Manateeshavepaddle-liketailsandfrequentfreshwater•Manateestendtocropandgrabwithprehensilelips•Manateesarelargerthandugongs•FewpredatorsThreats:•Carelessboaters•HabitatlossManateeManatee9.8ft,800-1200lbs3,000inU.S.Millionofyearsbeforepresent806040200AncestralmammalsAsianelephantAfricanelephanttmammothtmastadonDugongtStellar’sseacowWestIndianmanateeBrazilianmanateeWestAfricanmanateeOthermammalsRelationshipbetweenSireniansandelephants(mtDNA)Marinemammals:OrderCarnivora•AllmembersoforderCarnivorahaveprominentcanineteeth•Includes:–Seaotters–Polarbears–Pinnipeds(flipper-footed)•Walrus•Seals•Sealions/fursealsHawaiianMonkSealSeaOtterSeaOtter•Enhydralutris–NativetonorthPacific–394,000hairs/cm2–Noblubber–Female45lbs;Male65lbs–Diet:Seaurchins,abalone,mussels,clams,crabs,snailsandabout40othermarinespecies.–Usestools–Divesto330ft–RestsincoastalkelpforestsPopsize:22,000to27,000Weight:550to1,700poundsPolarBearPolarBear•Ursamaritimus–UnitedStates,Canada,Russia,GreenlandandontheArcticislandsofNorway–Male:10feettallandweighover1400lbs–Female:sevenfeetandweigh650lbs–wildpolarbearsliveuptoage25.–Goodswimmers–Thickblubber–ThickfurPolarbears•Polarbearsaretheleastadaptedtothemarinelifestyle•Landanimalsthatareadaptedtothecold•Consideredmarinemammalsbecausetheyfeedalmostexclusivelyonmarineorganisms•Verygoodswimmers,butcan’tdivebelowsurfacewell•Huntsealsandwalruses,occasionallycetaceansRange:•CircumpolarinArctic•Rangedependsonseaice•normalrangeoccasionalrangeoverpackoccasionalrangeoverpermanenticePinnipedsSeaLionWalrusFamilyPhocidaeFamilyOtariidaeFamilyOdobenidaeHawaiianMonkSealPinnipedsOrderPinniped(seals,sealions,&walruses)FamilyPhocidae-true,earlesssealsFamilyOtariidae-earedsealsandsealionsFamilyOdobenidae-walruses•34knownspecies•Evolved20myafromOrderCarnivora(ancestorsofdogsandbears)•DifferinpossessionofexternalearsandmodeoflocomotionBiologyandNaturalHistoryDifferencesbetweensealsandsealions/fursealsFamilyPhocidaeHawaiianMonkSeal•Lackexternalears•Hindflipperspropelthemwhileswimming•Frontflippersactasrudders•Travelonlandisdifficult(wiggle)SeaLionFamilyOtariidae•Earedseals•Frontflipperspropelanimalwhenswimming•Rearflippersactasrudders•FairlymobileonlandWalrusFamilyOdobenidae•FoundinArcticregion•Lackexternalears•Paddlewithfrontflippers•Rearflippersactasarudder•FairlymobileonlandPacificwalrusisinlavender,Atlanticwalrusisinrose.WalrusRangeMapWalrusFactsLocation:•Beringsea,PacificOcean,AtlanticOcean,ArcticOceanPopSize:•250,000Size:•Weight:2,000-3,500lb.Breeding:•Sexuallymaturelate-females,usually6-7years-males,15years.•ProducefewoffspringWalrusFactsLifestyle•Habit:Gregarious,livingmainlyinherds.•Diet:Benthicsuctionfeeders.Feedmainlyonbivalvemollusks,butalsootherinvertebratemarineanimals,fish,sometimessealsandwhales.•Predators:polarbears,killerwhales,andhumans•Lifespan:Upto40years.WalrusFacts•Swimspeed:7-35kph•Tusks:-Bothmale&female-Usedfordraggingbodyacrosslandorice-Symbolizeage,sex,andsocialstat