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TRANSCRIPT
ANZSCPB2016 2
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ANZSCPB2016 3
Australian and New Zealand Society for Comparative Physiology and Biochemistry
33rd Annual Meeting
1 - 4 December 2016
Western Sydney University Hawkesbury Campus
ANZSCPB2016 4
Organising Committee
Christopher Turbill, Jenny Harvey, David Thompson and Rebecca Drury
Sponsors
ArtworkbyDrGerhardKörtner
ANZSCPB2016 5
TableofContents
ConferenceSchedule.........................................................................................................6
ConferenceProgram..........................................................................................................7Thursday1December................................................................................................................7Friday2December.....................................................................................................................8Saturday3December................................................................................................................10Sunday4December...................................................................................................................12
Abstracts.........................................................................................................................13
ListofSpeakers................................................................................................................63
ContactDetails................................................................................................................64
ANZSCPB2016 6
ConferenceSchedule
Registrationandwood-firedpizzadinner17:00-20:00Thursday1DecemberatMemorialHall(R8)
Friday2December Saturday3December Sunday4December8:45 Welcomeand
announcements8:55 Announcements
9:00 PlenaryLecture 9:00 PlenaryLecture 9:15 Announcements9:45 Session1 9:45 Session5 9:30 Session910:30 MorningTea 10:30 MorningTea 10:35 MorningTea11:00 Session2 11:00 Session6 11:15 Session1012:30 Lunch 12:30 Lunch 12:30 Lunch13:30 Session3 13:30 Session7 Endofconference15:00 AfternoonTea 15:00 AfternoonTea 15:30 Session4 15:30 Session 16:05 AGM 17:00 Endofday 17:00 Endofday 18:30 ConferenceDinner
ANZSCPB2016 7
ConferenceProgram
Thursday1December
5:00–8:00pm
Registrationandwelcomedinneranddrinks.
MemorialHall(R8),HawkesburyCampus,WesternSydneyUniversity,Richmond
ANZSCPB2016 8
ConferenceProgram
Friday2December
*indicatesstudentseligibleforprizes
Chair:FritzGeiser
8:45 Announcements
9:00 PlenaryLecture:ClaudiaBieberandThomasRuf
Connectingecologyandphysiology:thelifehistorystrategyofapulseresourceconsumer
9:45 ChrisFriesen,NickyRollings,RandolphW.Krohmer,EmilyJ.Uhrig,HeatherL.Waye,RobertT.Mason,MatsOlssonandCamillaM.Whittington
SexanddeathintheCanadianbush:Sex-specifictelomeredynamicsinthered-sidedgartersnake
10:00 ChristopherTurbillandLisaStojanovski
Givingpredatorsthecoldshoulder:torporreducespredationriskinmice
10:15 NicolasMartin*,A.J.Hulbert,J.E.Bicudo,T.W.MitchellandP.L.Else
Longlivethequeen:influenceofdietonlongevityofhoneybees(Apismellifera)
10:30-11:00 MorningTea
Chair:MichaelThompson
11:00 LisaBromfield*,PaulRymerandChristopherTurbill
Metabolicrateofhousemiceinresponsetoairtemperatureandfoodavailability
11:15SPEEDTALK
JacintaKong*,AryHoffmannandMichaelR.Kearney
PredictingeggdevelopmentintheparthenogeneticgrasshopperWarramabavirgo(Orthoptera:Morabidae)
11:20 JessicaDudley*,BronwynM.McAllan,ChristopherR.MurphyandMichaelB.Thompson
EarlypregnancyintheAmericandesertrodentMerriam'sKangaroorat(Dipodomysmerriami)
11:35 HenriqueBraz,SelmaM.Almeida-Santos,ChristopherR.MurphyandMichaelB.Thompson
UterineandeggshellchangesassociatedwiththeevolutionofviviparityinSouthAmericanwatersnakes(Helicopsspp.)
11:50 CamillaWhittington,KevinDanastas,GeorgesGrau,ChristopherR.MurphyandMichaelB.Thompson
Angiogenesisinamniotepregnancy
12:05SPEEDTALK
MohammadKhan*,MichaelB.Thompson,MariaByrneandCamillaWhittington
Evolutionofmaternalfetalrelationshipsinmatrotrophicviviparousinvertebrate:ParvulastraparviviparaandCryptasterinahysteraasmodelorganisms
ANZSCPB2016 9
12:10 MelanieLaird*,HanonMcShea,BronwynM.McAllan,ChristopherR.MurphyandMichaelB.Thompson
UterinecelladhesiondynamicsduringpregnancyinMacropuseugenii(Macropodidae)andTrichosurusvulpecula(Phalangeridae)
12:25 Announcements-CraigFranklin:FundingopportunitiesfromSocietyofExperimentalBiologyandCompanyofBiologists
12:30-1:30 Lunch
Chair:ChristineCooper
1:30 CraigWhite,DustinMarshallandDanielOrtiz-Barrientos
Selectiondrivesmetabolicallometry
1:45 StewartMasson*,ChristopherHedges,JulesDevauxandAnthonyHickey
MitochondrialGlycerophosphateDehydrogenase:anewbumblebeethermogenesishypothesis
2:00 ElleMcDonald*andChristopherTurbill
Restingmetabolicrateofmotherspredictsoffspringgrowthrateinmice
2:25 ThomasNelson*andRogerS.Seymour
Avianbrainmetabolism:Arebirdsbird-brained?
2:30 SeanTomlinson,KingsleyDixonandS.DonBradshaw
Thebuzzonhoneybeeenergetics:Mismatchesbetweenmodelsandmeasurement
2:45 KarlJones*,SteveCooperandRogerS.Seymour
Respirationinsubterraneandivingbeetles
3:00-3:30 AfternoonTea
Chair:ChristineCooper
3:30 Announcements–ChristineCooper:IMC12PerthJuly2017
3:35 HughWinwood-Smith*,CraigWhiteandCraigE.Franklin
Metabolicdepressiononalowcarbdiet:amechanismtoconserveglycogen?
3:50 DanielGomez-Isaza*,RebeccaL.Cramp,RichardSmullenandCraigE.Franklin
Copingwithclimatechange:CandietimprovethethermalresilienceofBarramundi,Latescalcarifer?
4:05 AGM
ANZSCPB2016 10
ConferenceProgram
Saturday3December
*indicatesstudentseligibleforprizes
Chair:ChristopherTurbill
8:45 Announcements
9:00 PlenaryLecture:SteveSwoap,MariaVicent,JakeBingamanandElissaHutt
Utilizingthemousemodeltoexamineneuralmechanismsofdailytorpor
9:45 PhillipaK.Beale*,KarenFord,BenMooreandBillFoley
Interactionbetweenplantsecondarycompoundsandthermoregulationinmammalianherbivores
10:00 ZenonCzenze*,MarkBrigham,AnthonyHickeyandStuartParsons
Aren’tyoucold?SeasonaltorporexpressionandroostchoicedifferbetweenpopulationsofNewZealandbats
10:15 FritzGeiser,KristinaGasch,ClaudiaBieber,GabrielleL.Stalder,HannoGerritsmannandThomasRuf
Dohamstersbask?
10:30-11:00 MorningTea
Chair:ClaudiaBieber
11:00 StevenPortugal
Brightnights,costlymornings:night-timebodytemperatureincreasescorrespondwithmoonphaseandcloudlessnightsinwinteringBarnacleGeese(Brantaleucopsis)
11:15 ClareStawski,TaylorHume,GerhardKörtner,ShannonE.Currie,JuliaNowackandFritzGeiser
Post-firerecoveryofthebehaviourandphysiologyofasmallmarsupial
11:30 ChristineCooperandPhilipWithers
Controlofevaporativewaterlossbyaheterothermicdasyuridmarsupial
11:45 QiaohuiHu,RogerS.SeymourandEdwardP.Snelling
Ontogeneticscalingoffemoralbloodrateinwesterngreykangaroo(Macropusfuliginosus),easterngreykangaroo(Macropusgiganteus)andredkangaroo(Macropusrufus)
12:00 EliaPirtle*,ChristopherR.TracyandMichaelR.Kearney
Quantifyingtheinfluenceofphysiologyandbehaviouronreptilianevaporativewaterlossrates
12:15 NicholasWu*,RebeccaL.CrampandCraigE.Franklin
Livingwithaleakyskin:Upregulationofiontransportproteinsduringsloughing
12:30-1:30 Lunch
ANZSCPB2016 11
Chair:CraigWhite
1:30 PieterArnold*,PhillipCasseyandCraigWhite
Experimentalevolutionofdispersal-relatedtraitsinamodelinsect:morphological,physiological,andbehaviouralresponsestospatialselection
1:45 GerhardKörtnerandFritzGeiser
Doesaridityaffecthomerangesize?ThespatialecologyofAustralia'sdasyuridmarsupials
2:00 EdwardNarayan,AsumiWillis,CorinnevandenHoek,MandalaHunter-Ishikawa,RichardThompsonandTuanBendixsen
ConservationphysiologyofAsiaticblackbears(Ursusthibetanus):MonitoringstressandbehaviourinbearsrescuedfrombilefarmsinVietnam
2:15 PhilipWithers,LukeKealley,ChristineCooper,HarrietMillsandDominiqueBlache
Effectsofbehaviouralandphysiologicaltraitsonreleasebehaviourforash-greymice(Pseudomysalbocinereus)
2:30 KristenPetrov*,JamesVanDyke,NatashaMalkiewicz,JessicaLewis,MichaelB.ThompsonandRicky-JohnSpencer
Dietgeneralisationandspecialisationinafreshwaterturtle(Emyduramacquarii)
2:45 JamesVanDyke,MichaelKelly,KristenPetrov,FionaLoudonandRicky-JohnSpencer
Themechanisticbasesformaternaleffectsinturtles
3:00-3:30 AfternoonTea
Chair:JamesVanDyke
3:30 JulianBeaman*,CraigWhiteandFrankSeebacher
Evolutionofplasticity:mechanisticlinkbetweendevelopmentandreversibleacclimation
3:45 RebeccaL.Cramp,EdwardA.MeyerandCraigE.Franklin
LifeatlowpH:ThemechanisticbasisfortoleranceofextremelylowpHbyLimnodynastesterraereginaelarvae
4:00 JulesDevaux*,AnthonyHickeyandCrystalJames
Hypoxiatolerantspeciestakeadvantageofintracellularacidosistomaintainmitochondrialfunction
4:15 EnsiyehGhanizadehKazerouni,FrankSeebacherandCraigE.Franklin
Parentalenvironmentaffectsoffspring'sresponsestoUV-B
4:30 CrystalJames*,AnthonyHickey,JulesDevaux,ChristopherHedgesandStewartMasson
IshypoxiatolerancereflectedinNewZealandTriplefinbrains?(Tripterygiidae):Analysingenzymeactivitiesandmetabolites
4:45 JessicaK.McGlashan*,MichaelB.Thompson,FredricJ.Janzen,JamesVanDykeandRicky-JohnSpencer
Synchronoushatchinginfreshwaterturtles:metabolicandendocrinemechanisms
6:30 ConferenceDinneratTheSebelResort,Windsor
ANZSCPB2016 12
ConferenceProgram
Sunday4December
*indicatesstudentseligibleforprizes
Chair:CamillaWhittington
9:15 Announcements
9:30 YugoWatanabe*,BertDeGroefandSylviaV.H.Grommen
Regulatoryelementsthatdrivecorticotropin-releasinghormonereceptor2geneexpressioninavianthyrotropes
9:45 MelissaCameronandJohnDonald
Doesthespottedgar,Lepisosteusoculatus,expressafunctionalendothelialnitricoxidesynthase?
10:00 JohnDonald,NoorKhalidahAbdulHamidandJanetMcLeod
TheroleofleptinandghrelininappetiteregulationintheAustralianSpinifexhoppingmouse,Notomysalexis,duringlong-termwaterdeprivation
10:15SPEEDTALK
LesleyA.Alton,RebeccaL.Cramp,EmmaCeccato,FrankSeebacherandCraigE.Franklin
DNAdamageinducedbyultravioletradiationisrepairedfasterbyenzymaticphotoreactivationthanbynucleotideexcisionrepairinanamphibianspecies
10:20 EllyseNoy*,MelissaScott,DianaRayment,SylviaV.H.Grommen,KylieRobertandBertDeGroef
Thehypothalamo-pituitary-adrenalaxisinthefat-taileddunnart(Sminthopsiscrassicaudata),anAustralianmarsupial
10:35-11:15 MorningTea
Chair:RebeccaCramp
11:15 CraigE.Franklin,EssieRodgers,LilyBentleyandRossDwyer
Divinginawarmingworld:Environmentalandphysiologicaldeterminantsofdivedurationincrocodiles
11:30 MichaelKearney,WarrenP.PorterandStephenA.Murphy
AnestimateofthewaterbudgetfortheendangerednightparrotofAustraliaunderrecentandfutureclimates
11:45 PippaKern,RebeccaL.CrampandCraigE.Franklin
Stressorinteractionsshapeupperthermallimits
12:00 GillianRenshaw,JulesDevauxandAnthonyHickey
Mitochondrialplasticityasadeterminantofsurvivingclimatechange.
12:15 Finalannouncementsandawardpresentations
12:30-13:30 Lunchandendofconference
ANZSCPB2016 13
AbstractsPLENARYLECTURE
Connectingecologyandphysiology:thelifehistorystrategyofapulseresourceconsumer
ClaudiaBieberandThomasRuf
DepartmentofIntegrativeBiologyandEvolution,UniversityofVeterinaryMedicine,Vienna,Savoyenstraße1-1a,1160Vienna,Austria
Torporinmammals,i.e.,hibernation,aestivationanddailytorpor,isastateofmetabolicdepressionthatreducesenergyexpenditureduringunfavourableenvironmentalconditions.Here,weshowforthefirsttimethathibernationcanlast>11monthsinafree-livingsmallmammal.Edibledormice(Glisglis)arestronglyadaptedtotheavailabilityofseedtrees(i.e.,beechnutsFagussylvatica).Onlyinso-calledmastyearsdormiceinvestintoreproductionandraiseasinglelitterperyear.Inmastfailureyears,however,dormicegainweightbutthefoodseemsnotsufficienttoallowjuvenilestogrowandfattenpriortotheirfirsthibernationseason.Weshowherethatdormiceinmastfailureyearsretreatedearlyintohibernaculawhenenvironmentalconditionsweremildbutfoodavailabilitywasinsufficienttoraiseyoung.Wesuggestthatdormiceoptedforearlyhibernationonsettoavoidpredationandtoincreasesurvival.
Furthermore,recentevidencesuggeststhathibernatorsareparticularlylonglivedandthattheuseoftorpormayattenuatesenescence,i.e.decreasedcellularagingintermsofrelativetelomerelength(RTL)shortening.Thiscouldalsoexplainwhydormiceoptedtoprolonghibernationinayearwithoutreproduction.Surprisinglyhowever,RTLshorteningwaslargestinanimalsshowingextendedhibernation.Specifically,RTLshorteningwasassociatedwiththefrequencyofperiodicarousals,whichwashighestduringextremelylonghibernationseasonsstartinginearlysummer.Wethereforeconcludethathibernationmustaffectlongevityindirectly,bydecreasingtheriskofexternalmortality.Thisbenefitapparentlyoutweighsthepotentiallynegativeeffectofincreasedsenescence,especiallybecausedormiceareabletore-elongatetelomeresduringthesummer-activeseason.
ANZSCPB2016 14
SexanddeathintheCanadianbush:Sex-specifictelomeredynamicsinthered-sidedgartersnake
ChrisFriesen1,NickyRollings1,RandolphW.Krohmer2,EmilyJ.Uhrig3,HeatherL.Waye4,RobertT.Mason5,MatsOlsson6andCamillaM.Whittington1
1SchoolofLifeandEnvironmentalSciences,UniversityofSydney2DepartmentofBiologicalSciences,SaintXavierUniversity3DepartmentofPhysics,ChemistryandBiology,LinköpingUniversity4DivisionofScienceandMathematics,UniversityofMinnesota5DepartmentofIntegrativeBiology,OregonStateUniversity6DepartmentofBiological&EnvironmentalSciences,UniversityofGothenburg
Lifehistorystrategiesvarydramaticallybetweenthesexes,whichmaydrivedivergenceinsex-specificsenescenceandmortalityrates.Telomeresaretandemnucleotiderepeatsthatprotecttheendsofchromosomesfromerosionduringcelldivision.Telomereshavebeenimplicatedinsenescenceandmortalitybecausetheytendtoshortenwithstress,growthandage.Weinvestigatedage-specifictelomerelengthinfemaleandmalered-sidedgartersnakes,Thamnophissirtalisparietalis.Wehypothesizedthatage-specifictelomerelengthwoulddifferbetweenmalesandfemalesgiventheirdivergentreproductivestrategies.Malegartersnakesemergefromhibernationwithhighlevelsofcorticosterone,whichfacilitatesenergymobilizationtofuelmate-searching,courtship,andmatingbehavioursduringa2-4weekaphagousbreedingperiodatthedensite.Conversely,femalesremainatthedensforonlyaboutfourdaysandseemtoinvestmoreenergyingrowthandcellularmaintenance,astheyusuallyreproducebiennially.Asmaleinvestmentinreproductioninvolvesayearlyboutofphysiologicallystressfulactivities,whilefemalesprioritiseself-maintenance,wepredictedmalesnakeswouldexperiencemoreage-specifictelomerelossthanfemales.WeinvestigatedthispredictionusingskeletochronologytodeterminetheagesofindividualsandqPCRtodeterminetelomerelength.Forbothsexes,telomerelengthwaspositivelyrelatedtobodycondition.Telomerelengthdecreasedwithageinmalegartersnakes,butremainedstableinfemalesnakes.Therewasnocorrelationbetweentelomerelengthandgrowth(size/age)ineithersex,suggestingthatourresultsareaconsequenceofdivergentselectiononlifehistoriesofmalesandfemales.Differentselectiononthesexesmaybethephysiologicalconsequenceofthesexualdimorphismandmatingsystemdynamicsdisplayedbythisspecies.
ANZSCPB2016 15
Givingpredatorsthecoldshoulder:torporreducespredationriskinmice
ChristopherTurbillandLisaStojanovski
HawkesburyInstitutefortheEnvironment,WesternSydneyUniversity,HawkesburyCampus,Richmond2753,NewSouthWales,Australia
Torporprovidesamechanismformammalsandbirdstoreducetheirdailyenergyrequirements.Prolongeddeeptorpor,combinedwithfoodorfatstorage,allowshibernatingmammalstoremaindormantovertheentirewinterseason.Attheotherextreme,evenshortandshallowtorporboutswhilerestingprovideenergysavingsthatreducedailyforagingrequirements.Ourresearchaimstointegratethermoregulatoryeffectsonrestingenergyexpenditurewithforagingbehaviouranditslife-historyconsequences.Inthisstudy,wemeasuredthebodytemperatureofwild-caughthousemiceinresponsetovariationinperceivedpredationrisk.Wefoundthatmiceusetorporevenwhenfoodisavailabletofacilitateareductioninforagingeffortandhenceexposuretoaperceivedriskofmortalityfrompredation.Ourexperimentshowsthatenergysavingsfromtorporarerelevantinmodulating‘decisions’bymiceaboutforagingactivityinresponsetoenvironmentalconditions.
ANZSCPB2016 16
Longlivethequeen:influenceofdietonlongevityofhoneybees(Apismellifera)
NicolasMartin2,AnthonyJ.Hulbert2,J.EduardoBicudo2,ToddW.Mitchell1andPaulL.Else1
1SchoolofMedicine,UniversityofWollongong,NSW2522,Australia2SchoolofBiologicalSciences,UniversityofWollongong,NSW2522,Australia
Socialinsects,suchashoneybeesandants,haveexceptionallylong-livingqueensandareexcellentmodelstoinvestigatethebiologyofageing.Femalehoneybeesaregeneticallyidenticalyetcanbecomeeitherlong-livedqueens(upto8years)orshort-livedworkers(normally2-6weeks).Weareinvestigatingtheroleofdietarylipids,andtheiroxidation(i.e.peroxidation),toexplainthislongevitydifferenceinfemalehoneybees.Onlypolyunsaturatedfattyacids(PUFA)arecapableofsignificantperoxidationwithmonounsaturated(MUFA)andsaturatedfattyacidshighlyresistanttoperoxidation.Themembranelipidsoflarvae,pupae,emergentworkersandadultqueensallhavealowproportionofPUFAandhighproportionofMUFA.However,byday4followingemergence,workerbeesincreasetheproportionofPUFAintheirmembranesby5-fold(withaconsequentdecreaseinMUFA)unlikequeensthatretainalowproportionofPUFAintheirmembranes.Thischangeisduetotheconsumptionofpolleninworkerbeesfollowingemergencewhereasqueensdonotconsumepollenthroughouttheirlifeandarefed"royaljelly"mouth-to-mouthbyworkers.RoyaljellyhasanegligiblelevelofPUFA.Wepostulatethatthisdiet-inducedincreaseinmembranePUFAisresponsibleforthemuchshorterlifespansofworkerbeescomparedtoqueens.Thus,byfeedingemergentworkerbeesadietlowinPUFAaqueen-likemembranelipidcompositionshouldbeproducedandlifespanextended.PreliminaryresultsshowthatworkerbeesfedonadietwithnegligiblePUFAmaintainalowproportionofPUFAintheirmembranelipidsandlivelongercomparetoworkerbeesfeedingondietcontainingPUFA.Theabilitytoextendbeelifespanbynutritionalmanipulationwillprovideanimportantexperimentaltooltoinvestigatetheprocessofaging.
ANZSCPB2016 17
Metabolicrateofhousemiceinresponsetoairtemperatureandfoodavailability
LisaBromfield,PaulRymerandChristopherTurbill
HawkesburyInstitutefortheEnvironment,WesternSydneyUniversity,HawkesburyCampus,Richmond2753,NewSouthWales,AustraliaResearchisstillneededtounderstandtheecologicalsignificanceofmetabolicrateanditsrelationtootherkeytraitsthatdetermineanimalperformanceandevolutionaryfitness.Pasteffortstointegratemetabolismwithbehaviourandlife-historiesandhavereliedonbasalmetabolicrate(BMR)asasingleindexofindividualdifferencesinmetabolism.Yet,forsmallendotherms,metabolicrateisstronglyaffectedbythermoregulatorybehaviourandfoodavailability,andindividualdifferencesintheseresponsesmightalsobeimportantrepeatablemetabolictraits.Wemeasuredthemetabolicrateofwild-caughthousemiceinhomecagesexposedtoadailytemperaturecycle(15,20,31°C)andalternate-dayfoodwithdrawal.Respirometrytrialslastedsixdaysandwererepeatedthreetimesoverthreemonthperiodsforallindividuals.Weusedthesedetailedlongitudinalmeasurementstoexaminethemeaneffectsoftemperatureandfoodavailability,individualdifferencesinresponses,andtheinterrelationsamongindividualvariationinminimumdailyvaluesofrestingmetabolicrate(RMR)at15,20,31°Candintegratedenergyexpenditureoverthedailycycle.Inthistalk,Iwillpresentaninitialexplorationofourresults,whichhaveonlyjustbeencompleted.Weusetheseresultstosuggesthowconsistentindividualdifferencesinthermoregulatorymetabolicresponsestofoodavailabilitycouldplayanimportantroleinthedefiningvariationin'pace-of-life'(i.e.metabolic-behavioural-life-history)syndromes.
ANZSCPB2016 18
SPEEDTALK
PredictingeggdevelopmentintheparthenogeneticgrasshopperWarramabavirgo(Orthoptera:Morabidae)
JacintaKong,AryHoffmannandMichaelR.Kearney
SchoolofBioSciences,theUniversityofMelbourne,Parkville,Australia3010
Understandingtheinsectlifecycleisakeyproblemforpredictinginsectresponsestoclimate,andforthemanagementandconservationofspecies.Theeggstagerepresentsthefecundityofonegenerationandthesurvivalofthenext.Physiologicaladaptations,suchasdormancy,ofimmobileeggscanregulatesurvivalanddevelopmentundervariablelocalenvironmentalconditions.Complexinsectlifecyclescanarisewhendevelopmentaltraitsvarydependingonenvironmentalconditionsandunderlyinggenetictraits.Parthenogeneticinsectsallowustoinvestigatedevelopmentalresponsesofeggstoclimateinasimplifiedgeneticsystem.Here,wecharacterisedeggdevelopmentunderconstantandfluctuatingtemperaturesintheparthenogeneticandwinglessgrasshopperWarramabavirgo.WeexaminedtheadaptivesignificanceofeggdormancyforpopulationsofW.virgoacrossEasternAustralia.Variationineggdevelopmentundervarioustemperatureregimeshighlightsthelimitationsofgeneralisinglaboratoryexperimentstothefield,andthechallengesfordevelopingmechanisticmodelsofinsectresponsestoclimate.
ANZSCPB2016 19
EarlypregnancyintheAmericandesertrodentMerriam'sKangaroorat(Dipodomysmerriami)
JessicaDudley1,BronwynM.McAllan1,ChristopherR.Murphy1andMichaelB.Thompson2
1SchoolofMedicalSciences,TheUniversityofSydney,NSW2006,Australia2SchoolofLifeandEnvironmentalSciences,TheUniversityofSydney,NSW2006,Australia
Theuterinesurfaceundergoessignificantremodelingduringpregnancytoallowforimplantationoftheblastocyst(cellmasssubsequentlyformingtheembryo).Thesechanges,collectivelytermedthe‘plasmamembranetransformation’(PMT),occurregardlessoftheplacentationtypethatfollows.SimilaritiesinmorphologicalandmolecularchangesduringthePMTinviviparouslizardsandmarsupialssuggestthatcommonmoleculesplayanimportantroleinattachmentofthetrophoblastacrossspecies.Althoughplacentationhasevolvedonlyonceinmammalsthereareseveraldifferentanatomicalvariationsoftheplacentainmammals.Kangaroorats(Dipodomysspp.)donotexhibitthetypicalhemochorial(highlyinvasive)placentaofspecieswithinthesuperorderEuarchontoglires(rodents,rabbitsandhares,treeshrews,flyinglemursandprimates).Insteadtheyexhibitalessinvasiveform,endotheliochorial(slightlyinvasive)placentawithlittleknownaboutthemolecularmechanismsunderpinningitsformation.Thus,wecharacterisedthechangesthatoccurtomembranemoleculesandtothecellularultrastructureoftheuterineepitheliumduringearlypregnancyinMerriam’skangaroorat,Dipodomysmerriami.Weusedelectronmicroscopyandimmunofluorescencemicroscopytodescribechangestotransmembraneproteinsandthestructuralandluminalsurfaceofuterineepithelialcellsduringpregnancy.Theseadhesionmoleculesincludedcadherins,whichformtheadherensjunctionanddesmosomeswhichformadhesion‘spotwelds’alongthelateralplasmamembrane,providingstructuralintegritytothetissue.Cadherinsdecreaseinexpressionintheuterineepitheliumduringthepre-implantationperiodandthereisaredistributionofdesmosomestotheapicalregionofthelateralplasmamembrane.Theshiftindesmosomeandcadherindistributionbeforeimplantationsuggeststhatthereisareductioninlateraladhesionbetweenepithelialcellstoallowforinvasionbytheblastocyst.DespiteKangarooratsformingalessinvasiveplacentathesesamechangesoccurduringpregnancyinspecieswithhighlyinvasiveplacentationsuchasthelabratandhuman.
ANZSCPB2016 20
UterineandeggshellchangesassociatedwiththeevolutionofviviparityinSouthAmericanwatersnakes(Helicopsspp.)
HenriqueBraz1,SelmaM.Almeida-Santos2,ChristopherR.Murphy3andMichaelB.Thompson1
1SchoolofLifeandEnvironmentalSciences,UniversityofSydney2LaboratoryofEcologyandEvolution,ButantanInstitute,Brazil3SchoolofMedicalScienceandBoschInstitute,UniversityofSydney,Australia
Theevolutionofreptilianviviparityrequiresthattheeggshellisreducedtobringtogethertheuterineepitheliumandextraembryonicmembranestoformplacentaeforphysiologicalexchanges.Themechanismbywhichtheeggshellisreducedinthicknesslikelyinvolvesreducingtheactivityoftheglandsthatsecreteit.WetestedthishypothesisusingtheNeotropicalwatersnakes(Helicops).Helicopsspeciesexhibitintragenericandintraspecificvariationinreproductivemode,andviviparityhasevolvedthreetimesindependentlyinthegenus.Thusitisanexcellentmodelforinvestigatingoviparity-viviparitytransitions.TheuteriofoviparousandviviparousHelicopsarestructurallysimilarandparallelcyclicvariationsinmorphology.Duringprimaryvitellogenesis,theluminalepitheliumisthinandglandsarepoorlydeveloped.Theepithelialthicknessanduterineglandssignificantlyincreaseduringsecondaryvitellogenesis,butoviparousspeciesalwaysshowthelargestincreasesinuterineglandsize.Uterineglanddimensionsaresimilaramongspecieswiththesamereproductivemode.Duringpregnancy,theepitheliumislowandglandsaredepletedinthedistendeduteri.Aneggshellispresentinbothoviparousandviviparousspecies.Nevertheless,theeggshellinviviparousHelicopslacksanexternalminerallayerandisthinnerthaninoviparousrelatives.Boththeuterineglandsandepitheliumsecretetheeggshell,withtheepitheliumsecretingtheinnerboundary,andtheglandssecretingtheproteinaceousfibresoftheeggshell.Ourresultssupportthehypothesisthateggshellthinningisassociatedwiththeevolutionofviviparityandthatsuchthinningresultsfromlessdevelopedglandsinviviparousthaninoviparoustaxa.
ANZSCPB2016 21
Angiogenesisinamniotepregnancy
CamillaWhittington1,KevinDanastas2,GeorgesGrau2,ChristopherR.Murphy2andMichaelB.Thompson1
1SchoolofLifeandEnvironmentalSciences,UniversityofSydney2SchoolofMedicalSciences,BoschInstitute,UniversityofSydney
Vascularendothelialgrowthfactorisamajormediatorofangiogenesis,acriticallyimportantprocessinvertebrategrowthanddevelopment,andinpregnancy.ThesplicevariantVEGF111isarareisoformfoundpreviouslyonlyinDNA-damagedhumancells,untilitsdiscoveryintheuterusofAustralianskinks.WemeasuredexpressionofVEGF111andtwomajorVEGF-Asplicevariantsintheuterusofpregnantrats,showingthatthethreevariantshavedifferentexpressionpatternsacrosspregnancy.Wehavenowidentifiedthisunusuallypotentsplicevariantinvivoinbothmarsupialandeutherianmammals.OurresultssuggestthatviviparousmammalspossessapreciselyregulatedmilieuofVEGFisoformsproducingtheangiogenesisrequiredforsuccessfulpregnancyandthatVEGF111maybecommontoallmammals,andpotentiallywidespreadinamniotepregnancy.ThediscoveryofVEGF111inratuteruspavesthewayforthedevelopmentofinvivomodelsofVEGF111activityinahighlytractablelaboratoryanimal,andisparticularlysignificantinthecontextofearlypregnancylossandcancerresearch.
ANZSCPB2016 22
SPEEDTALK
Evolutionofmaternalfetalrelationshipsinmatrotrophicviviparousinvertebrate:ParvulastraparviviparaandCryptasterinahysteraasmodelorganisms
MohammadKhan,MichaelB.Thompson,MariaByrneandCamillaWhittington
UniversityofSydney
Matrotrophicbroodinginaplacentalviviparousanimalsinvolvesadiverserangeofmaternal-fetalrelationshipsindifferentphyla,andincludesintragonadallecithotrophicbroodingintheEchinodermata.Theevolutionofviviparityrequiresinternalfertilizationandretentionofoffspring,buttheevolutionofmatrotrophyrequiresextraembryonicnutritiontobeprovidedtotheoffspringwithinthemother’sbody.Ininvertebrates,viviparityisassociatedwithspecializedphysiologicalandmorphologicalmechanisms.Iaimtoidentifythemechanismsthatareresponsiblefortheevolutionofviviparityinmarineinvertebrates.Iwilldescribethebroodingmechanisms,gonadalmorphologicalchangesandmoleculesinvolvedinevolutionofviviparousmatrotrophicandbroadcastspawningstarfishestoassessthemorphologicalchangesassociatedwithevolutionofviviparityintwointragonadalviviparousmatrotrophicinvertebratesParvulastraparviviparaandCryptasterinahystera.Advancednon-invasiveimagingtechniques(μCT),microscopy,laboratoryobservationandtranscriptomicswillbeusedtodescribethecellularandmolecularmechanismsthatenablematrotrophicbrooding.Broodarrangementwillbecharacterizedbyusingmicro-computedtomography(μCT)ofthewholeseastar.Morphologicalmodificationinthegonadalepithelialcellthatmayberequiredforviviparouslarvaldevelopmentwillbestudiedusingtransmissionelectronmicroscopy.IwillalsolocatemembranemoleculesindifferentstagesofbirththroughimmunofluorescencemicroscopyandwesternblottingtoconfirmthepresenceofspecificmembranemoleculesinP.parviviparaandC.hystera.RNA-Seqwillbeappliedtoidentifyandquantifydifferencesinthegenesexpressedinthereproductivetissuesbetweenbroadcastersandviviparousseastars.
ANZSCPB2016 23
UterinecelladhesiondynamicsduringpregnancyinMacropuseugenii(Macropodidae)andTrichosurusvulpecula(Phalangeridae)
MelanieLaird1,HanonMcShea2,BronwynM.McAllan,ChristopherR.Murphy4andMichaelB.Thompson1
1SchoolofLifeandEnvironmentalSciences,UniversityofSydney2DepartmentofOrganismicandEvolutionaryBiology,HarvardUniversity,Cambridge,MA,USA3DepartmentofPhysiology,FacultyofMedicine,UniversityofSydney4DepartmentofAnatomyandHistology,FacultyofMedicine,UniversityofSydney
Successfulmammalianpregnancyrequiresremodellingoftheuterustobecomereceptivetoembryonicattachment.Whilesimilarmorphologicalchangestotheuterineepitheliumoccurinbotheutherian(placental)mammalsandmarsupials,themarsupialuterusemploysmaternaldefences,includingreinforcementoftheuterineepithelium,toregulateembryonicinvasion.Sincenon-invasiveembryonicattachmentinmarsupialslikelyevolvedsecondarilyfrominvasiveattachment,uterinedefencesinthesespeciesmayevenpreventembryonicinvasion.Totestthishypothesis,weidentifiedpatternsoffluorescenceofakeymoleculeinvolvedinmaintaininglateralcell-celladhesionoftheuterineepithelium(desmoglein-2)throughoutpregnancyinthebrushtailpossum(Trichosurusvulpecula;Phalangeridae)andthetammarwallaby(Macropuseugenii;Macropodidae),eachfromamarsupialcladeinwhichnon-invasiveattachmenthasevolvedindependently.Ineutherianandmarsupialspecieswithinvasiveplacentation,apicalredistributionofdesmoglein-2pre-attachmentreducescell-celladhesionoftheuterineepitheliumandfacilitatesinvasion.Interestingly,bothM.eugeniiandT.vulpeculaundergothissameapicalredistribution,suggestingthatcelladhesion,andthusintegrityoftheuterineepithelium,isreducedduringtheattachmentperiodregardlessofplacentaltype.However,bothspeciesshowadditionaluniquepatternsofdesmoglein-2localisation,includingstrongbasallocalisationforM.eugeniiandnuclearlocalisationforT.vulpecula,whichsuggestthatdesmoglein-2playsadditionalrolesinthesespecies.Hence,species-specificlocalisationofdesmoglein-2inM.eugeniiandT.vulpeculamaybeinvolvedinpreventingembryonicinvasionoftheuterusbycompensatingforthereducedcelladhesionandmaintaininganintactepithelialbarrier.
ANZSCPB2016 24
Selectiondrivesmetabolicallometry
CraigWhite1,DustinMarshall1andDanielOrtiz-Barrientos2
1SchoolofBiologicalSciences,MonashUniversity 2SchoolofBiologicalSciences,TheUniversityofQueenslandLivingspeciesvaryinsizefrom~0.1pgsingle-celledmicro-organismstotreesweighingseveralthousandstonnes.Putinperspective,this~1021-foldrangeissimilartothedifferenceinmassbetweenanelephantandtheEarthitself.Theinfluenceofmassonbiologicalprocessesispervasive,butisusuallyallometric:a10-foldincreaseinmassistypicallyaccompaniedbyjusta4-to-7-foldincreaseinmetabolicrate.Understandingthebasisofallometricscalingisalong-standingprobleminbiology.Here,weshowtheinterspecificrelationshipbetweenmetabolicrateandbodymassarisesasaconsequenceofcorrelationalselectiononthesetraits,coupledwithnegativedirectionalselectiononabsolutemetabolicrate.Thispatternofselectionexplainsnotonlythecovariancebetweenmetabolicrateandbodymass(theallometricscalingofmetabolicrate),butalsoexplainsthemagnitudeoftheconditionalvarianceinmetabolicrate.Thecorrelationalselectionwedocumentconstraintstheevolutionofmass-specificmetabolicrates(MSMR)suchthattheobservedrangeofMSMRsisjust50-foldamongspeciesthatdifferinsizebytenbillion-fold.Ourresultslinkmicroevolutionaryprocessestomacroevolutionarypatternstodescribetheevolutionofmetabolicallometryinanimals.
ANZSCPB2016 25
MitochondrialGlycerophosphateDehydrogenase:anewbumblebeethermogenesishypothesis
StewartMasson,ChristopherHedges,JulesDevauxandAnthonyHickey
SchoolofBiologicalSciences,UniversityofAuckland
Bumblebees(Bombusterrestris)areanenigmaticspeciesastheycanflyattemperatureslowerthanmanyotherinsects.Whilebumblebeeshaveadaptationsthatadvantageheatretention,i.e.thermalinertiathroughlargebodymassandgreaterinsulation,theyrequireamechanismtowarmflightmuscleswithoutshivering,asthisdoesnotoccuruntil20oC.Precisemechanismsofheatgenerationareyettobefullyelucidated,withpreviousworksuggestingthatfutilecyclingofglycolyticandgluconeogenicintermediatesreleasessufficientheatforshiveringtothenwarmmuscles.However,predictionsoffluxthroughthesepathwayscanonlyaccountfor10%oftheheatrequiredtoheatthethoraxmusclesforflight.
Herewepresentanewhypothesisbasedonthemitochondrialglycerophosphatedehydrogenase(mGPDH)pathway.AnalysisofrespirationuncoveredpoorcouplingofthispathwaytoATPsynthesis,aswellassignificantrespirationratesintheabsenceofexogenousADP;comparabletopre-flightconditionsinthetissue.ComplimentaryanalyseswithapurposebuiltcalorimetershowedsignificantheatgenerationfromflightmusclerespiringintheabsenceofADPwithmGPDHsubstrateglycerol-3-phospahe(G3P)relativetoComplexIsubstratepyruvate.OtheranalysesconductedatlowtemperatureshowedthatG3P-supportedrespirationislessaffectedbylowtemperaturethanothermitochondrialrespiratorypathways.Furthermore,theapparentaffinityofmGPDHforG3PsuggeststhattemperaturemayplayaroleinthepassiveregulationofmGPDHasathermogenicmechanism.
WeconcludethatmGPDHmayprovideatemperature-sensitivemechanismadditivetofutilesubstratecyclingtowarmbeeflightmusclepriortoshivering.
ANZSCPB2016 26
Restingmetabolicrateofmotherspredictsoffspringgrowthrateinmice
ElleMcDonaldandChristopherTurbill
HawkesburyInstitutefortheEnvironment,WesternSydneyUniversity,HawkesburyCampus,Richmond2753,NewSouthWales,AustraliaCurrenthypothesesmakecontrastingpredictionsregardinghowrestingmetabolicrate(RMR)relatestototaldailyenergyexpenditure(DEE).ThecompensationhypothesisproposesanegativerelationshipbetweenRMRandDEEbecauselowmaintenanceenergycostswouldallowmoreenergytobeallocatedtoothercostssuchasactivity,growthandreproduction.Incontrast,theincreasedintakehypothesispostulatesapositiverelationshipbetweenRMRandDEEbecausehighmaintenanceenergycostscouldbeindicativeofalarger'metabolicengine'thatiscapableofprocessingfoodintoenergyatafasterrate,therebyincreasingtheamountofenergythatcanbeallocatedtoproduction.WeaimedtotestthesehypothesesbyfirstdeterminingtherepeatabilityofRMRandDEE,andthenassessingtheecologicalconsequencesofvariationinRMRbymeasuringreproductiveoutput.
WemeasuredtheRMRandDEEof‘diversityoutbred’(J:DO)laboratorymice(n=97)whichexhibitedawiderangeofmetabolicphenotypes.Metabolicratewasmeasuredinresponsetovariabletemperatureandfoodavailabilityduringthreerespirometrytrials,eachlastingfourdays,overoneyear.RMRat31°C,equivalenttobasalMR(BMR),exhibitedrepeatabilityacrossthethreetrials(ICC,0.26).RMRat15°C(RMR15),whichaccountsforthermoregulatoryresponsessuchastorporuse,showedlowerrepeatabilityacrosstrials(ICC,0.13)andtotalDEEdisplayedthehighestrepeatabilityacrosstrials(ICC,0.34).Asubsetoffemalemice(n=47)werebredoncetodetermineifRMRaffectsoffspringproduction.Wefoundanegativerelationshipbetweenamother’sBMRandthegrowthrateofheroffspring,afteraccountingforeffectsofRMR15,bodymass,littersize,andsexratio.Onaverage,offspringfrommotherswithBMRinthelowest10thpercentilewere4.46glighteratthetimeofweaningthanoffspringfrommotherswithBMRinthe90thpercentile.Conversely,RMR15hadapositiveeffectongrowthrate.
TheseresultssuggestthatBMRrepresentsanenergycostallocatedawayfromgrowth,thereforeprovidingsupportforthecompensationhypothesis.ThepositiveeffectofRMR15mightbeexplainedifRMRisrepresentativeofmetabolicscope.IncreasedoffspringgrowthratesinmotherswithlowBMR(lowmaintenanceandheatproduction)andhighRMR15(highthermalconductance)isalsopredictedbytheheatdissipationlimitationhypothesis.Thesepreliminaryresultsprovideasolidfoundationfordeterminingtheecologicalfunctionofvariationinmetabolicrate.
ANZSCPB2016 27
Avianbrainmetabolism:Arebirdsbird-brained?
ThomasNelsonandRogerS.Seymour
SchoolofBiologicalSciences,UniversityofAdelaide
Manycomparisonshavebeendrawnbetweentheintelligenceandcognitionofprimateandavianspecies,withsomestudiesputtingforthprimateandavianintelligenceasacaseofconvergentevolution.Cerebralperfusionisdirectlyrelatedtothemetabolicrateofthebrainandcognitiveability.Recently,atechniqueofestimatingcerebralperfusionfromthesizeofthebonyforaminaoftheskullhasbeendeveloped.Cerebralbloodflowinbirdsisprincipallyderivedfromtheinternalcarotidandvertebralarterieswhichanastomoseatthebaseofthebrain.WeusedX-raycomputedtomographytotakecranialmeasurementsofbrainvolumeandcarotidforaminaradiusfromarangeofavianspecies.Betterunderstandingoftheratescerebralperfusionratesindifferentgroupsofbirdscanleadtointerestingcorrelationsbetweencranialarterialsizeandanimalbehaviour.Thisapproachissofaruniqueandpromisestoprovidefurtherinsightsintobothlivingandextinctspecies.
ANZSCPB2016 28
Thebuzzonhoneybeeenergetics:Mismatchesbetweenmodelsandmeasurement
SeanTomlinson1,KingsleyDixon1andS.DonBradshaw2
1DepartmentofEnvironmentandAgriculture,CurtinUniversity2SchoolofAnimalBiology,UniversityofWesternAustraliaWithafewexceptions,themeasurementoffieldmetabolicrate(FMR)infree-ranginginsectshasprovenimpossiblethusfar.Hereweprovideareviewoftheuseofradio-isotopicturnoverstomeasuremetabolicrate(VCO2),andconfirmthatVCO2oftheHoneybeeApismelliferawassignificantlypredictedby86Rbkb(r2=0.57,p=0.002),andconformedtoexpectationsforanectothermicspecies.Themassofhoneysolutionconsumedwassignificantlyrelatedto22Nakb(r2=0.48,p=0.008).Weappliedthesecalibrationstothestudyoffree-rangingworkerbeesinlandscapeswithdifferentlevelsofanthropogenicdisruption.TherewereunexpecteddifferencesinFMRandfoodintakebetweenthetwodifferentlandscapecontexts.Honeybeesindeforestedlandscapesprobablyforagedlessanddependeduponstoredresourcesduringourstudy.Weconcludethatradio-isotopictechniquescanbeparticularlyusefulforestimatingFMRofinsects.Theuseofsuchtechniquescaninformecophysiologically-basedquestionsonecosystemfunction,productivityandconservationandlandmanagementthathavepreviouslybeenbeyondreachininsectsystems.
ANZSCPB2016 29
Respirationinsubterraneandivingbeetles
KarlJones1,SteveCooper2,3andRogerS.Seymour1
1DepartmentofEcology&EnvironmentalSciences,UniversityofAdelaide2EvolutionaryBiologyUnit,SouthAustralianMuseum3AustralianCentreforEvolutionaryBiologyandBiodiversity,SchoolofBiologicalSciences,UniversityofAdelaide
Respirationinmanysurfacedwellingdivingbeetles(Coleoptera:Dytiscidae)hasbeenwellunderstoodforacentury.Beetlescollectanairbubblewhichisstoredunderneaththeelytrafromwhichoxygenisconsumedduringthedive.Asmallbubblepushedfromthetipoftheabdomencanalsobeusedtoextractoxygenfromthewater.However,thisairstorestillrequiresperiodicreplenishmentatthesurface.Severalepigeansubmergenttolerantdytiscidshavebeenidentifiedandrecentstudiessuggestthesebeetlesmayutiliseporesorsetaeontheirsurfacesforoxygenuptakenegatingtheneedtoreturntothesurface.However,respirationinsubterraneandytiscidsisnotunderstood.WeinvestigatedrespirationinstygobiticdytiscidsfromcalcreteaquifersoftheYilgarnregioninWesternAustralia.Therehavebeennumerousindependentevolutionaryincursionsintothesubterraneanenvironmentbyancestralsurfacedytiscids,aswellasinsituspeciationwithincalcretes,resultinginthemostdiverseassemblageofsubterraneandytiscidsintheworld.Weusedmicroscopy,respirometry,fibre-opticoxygensensors,andsubmergenceexperimentstoexplorerespirationintwosympatricsisterspecies,Parostermacrosturtensis(3.6–4.1mmlong)andParostermesosturtensis,(1.9–2.3mmlong)andanindependentlyevolvedsubterraneanspeciesLimbodessuspalmulaoides(4.2mmlong).Allthreespeciescanconsumeoxygenfromwater,andhaveanoxygenboundarylayer,butlackstructuresthatcouldhaverespiratoryfunctionsuchasporesorsetae.P.macrosturtensishasalowmetabolicrate,only25%ofthatpredictedbyotherinsects,andcantolerateatleast12daysofsubmergence.Theseresultsindicatethatthesebeetlesrespirecutaneouslyandthatthismodeofrespirationhasevolvedindependentlyatleasttwiceinsubterraneandytiscids.Thisadaptationlimitsbeetlesizeduetoamismatchbetweenmetabolismandsurfacearea,buthasledtoanextraordinaryradiationofsubterraneanbeetles.
ANZSCPB2016 30
Metabolicdepressiononalowcarbdiet:amechanismtoconserveglycogen?
HughWinwood-Smith1,CraigWhite2andCraigE.Franklin1
1SchoolofBiologicalSciences,UniversityofQueensland2MonashUniversity
Long-termstudieshavefoundlowcarbohydratedietsaremoreeffectiveforweightlossthancalorierestricteddietsintheshort-term,butequallyoronlymarginallymoreeffectiveinthelong-term.Lowcarbohydratedietshavebeenlinkedtoreducedglycogenstoresandincreasedfeelingsoffatigue.Weproposethatreducedphysicalactivityinresponsetoloweredglycogenexplainsthediminishingweightlossadvantageoflowcarbohydratecomparedtolowcaloriedietsoverlongertimescales.WeexploredthispossibilitybyfeedingadultDrosophilamelanogastereitherastandardorlowcarbohydratedietforninedaysandmeasuredchangesinmetabolicrate,glycogenstores,activity,andbodymass.Wehypothesisedthatalowcarbohydratedietwouldcauseareductioninglycogenstoresthatrecoversovertime,reducedphysicalactivity,andanincreaseinrestingmetabolicrate.Thelowcarbohydratedietwasfoundtoreduceglycogenstores,whichrecoveredovertime.Activitywasunaffectedbydietbutthelowcarbohydrategroupexperiencedareductioninmetabolicrate.Weconcludethatmetabolicdepressioncouldexplainthedecreasedeffectivenessoflowcarbohydratedietsovertimeandrecommendfurtherinvestigationoflong-termmetaboliceffectsofdietaryinterventionsandagreaterfocusonphysiologicalplasticitywithinthestudyofhumannutrition.
ANZSCPB2016 31
Copingwithclimatechange:CandietimprovethethermalresilienceofBarramundi,Latescalcarifer?
DanielGomez-Isaza1,RebeccaL.Cramp1,RichardSmullen2andCraigE.Franklin1
1SchoolofBiologicalSciences,TheUniversityofQueensland2RidleyAqua-Feed
Environmentaltemperaturehasbeenidentifiedasthesinglemostinfluentialfactor,directlyaffectingkeyphysiologicalprocessessuchasmetabolismandlocomotioninectotherms,includingeconomicallyimportantculturedspecies.Thisisbecomingamajorconcernassomespecies(e.g.salmonids)arenowbeingculturedinwatersclosetotheupperthermallimits.Muchofthecurrentresearchaimstodevelopdietsthatmaintainorenhancefishgrowthwhilstincreasingresiliencetohightemperatures.Here,weexaminedifdiet(highfatvs.lowfat)canimprovethegrowthperformanceinjuvenilebarramundi(~3.2±0.07g)whileincreasingtheirresiliencetoacutethermalstress.Thehighfatdietincreasedfishgrowthcomparedtothelowfatdiet,buthadnoeffectonthethermalsensitivityofperformancetraits.However,fishfedthehighfatdietshowedanoverallreductioninwholeanimalthermaltolerance(CTMax).Together,theseresultsindicatethathighfatdietsmaintainaerobicperformanceathightemperaturesandincreasesgrowthperformancehenceitmaybebeneficialforaquaculturalproductioninawarmingworld.
ANZSCPB2016 32
PLENARYLECTURE
Utilizingthemousemodeltoexamineneuralmechanismsofdailytorpor
SteveSwoap,MariaVicent,JakeBingamanandElissaHult
BiologyDepartment,WilliamsCollege
Inresponsetofoodscarcityandlowambienttemperature,miceenterboutsoftorporresultinginenergyconservation.Tomediatethetorporresponse,thebrainrequiresinputrelayinginformationconcerningtheenvironment(nutrients,temperature,etc).Thebrainalsohasseparatecenterstoevokethephysiologicalchangesoftorpor.However,theneuralmechanismsandcircuitsinvolvedwithdailytorporareunknown.Weusedtwoapproachestowardsidentifyingthedifferentregionswithinthebrainthatareinvolvedinthetorporresponse.First,wetookacomparativeapproach,comparingthephysiologicaleffectsoftorporvs.diving,asthosebrainstemregionsinvolvedinmediatingthedivingresponseareknown.Wehypothesizedthatthecardiovasculareffectsinvolvedinthemurinediveresponse(dropinheartrate,fallinbloodpressure,andconstrictionofperipheralbloodvessels)aresimilartothoseusedindailytorpor.Thephysiologicalresponsestotorporanddivingwereindistinguishable.Duringbothdivingandtorpor,diastolicBPfelldropped1.5x:theinterbeatintervalincreased4x,andtotalperipheralresistanceincreased4xrelativetocontrol.Thesedatasuggestthatthedriversofthecardiovascularchangesduringaboutoftorporandduringthedivingresponsearelikelyshared.Second,weusedoptogeneticstoexaminetheroleofAgouti-relatedprotein(AgRP)containingneuronsinthearcuatenucleusofthehypothalamusindailytorpor.Astheseneuronssensecirculatingcuesofenergyavailability,wehypothesizedthatdirectstimulationofAgRPneuronswoulddecreasetheminimumTboftorpidmiceandincreasethetimespentintorpor.Totestthishypothesis,hypothalamicAgRPneuronswereselectivelytargetedwiththelight-sensitivechannelrhodopsin-2transgene.Micewerecaloricallyrestricteddaily(65%ofnormalcaloricintake)untilregulardailytorporboutswereachieved.Onbaselinedays,whenAgRPneuronswerenotactivated,minimumTbwas25.6±0.8°Candtimeintorporwas233±34minutes.WhenAgRPneuronswerestimulatedforonehourduringentryintotorpor(20Hzfor1secondevery4secondsfor60minutes),minimumTbwassignificantlylower(22.8±0.3°C)andtorporboutsweresignificantlylonger(435±29min).ThesedatasupportthehypothesisthatAgRPneuronsdirectlyregulatetorporphysiology.
ANZSCPB2016 33
Interactionbetweenplantsecondarycompoundsandthermoregulationinmammalianherbivores
PhillipaK.Beale1,KarenFord1,BenMoore2andBillFoley1
1AustralianNationalUniversity2UniversityofWesternSydney
Throughmechanismsthatcontrolthegeneration,conservationanddissipationofheat,endothermscanmaintainarelativelyconstantTbacrossabroadrangeofambienttemperatures.Thedietofmammalianherbivoresisfundamentallylinkedtothermoregulation.However,theinterplaybetweendietselectionandambienttemperatureisoftenoverlookedinecology.Thedietofherbivoresinparticularcontainsplantsecondarycompoundsthatareabletoalterthephysiologicalprocessesresponsibleforappropriatethermoregulationinmultipleways,suchasbyuncouplingmitochondria,bindingtothermoreceptors,orbecausethepathwaysrequiredtometaboliseplantsecondarycompoundsarethermogenic.Theseinteractionsmaybecomemoreimportantasambienttemperaturerisessincedissipatingexcessbodyheatintotheenvironmentbecomesmoredifficult.Itislikely,therefore,thattheimplicationsofariseinambienttemperaturearegreaterforherbivoresthanforothermammals,andthataneedtomanageinternalandexternalheatloadsundertheseconditionscoulddrivechangesinfeedingecology.Dataontheroleoftheliverindetoxificationatelevatedtemperaturesandtheuncouplingpotentialofcommonsecondarymetaboliteswillbedescribed.
ANZSCPB2016 34
Aren’tyoucold?SeasonaltorporexpressionandroostchoicedifferbetweenpopulationsofNewZealandbats
ZenonCzenze1,MarkBrigham2,AnthonyHickey1andStuartParsons3
1UniversityofAuckland 2UniversityofRegina3QueenslandUniversityofTechnology
Variationsinweatherandfoodavailabilitydifferentiallyimpactstheenergybudgetsofendotherms.Therehasbeenconsiderablefocusonthethermalphysiologyofspeciesthatexperienceextremeseasonaldifferences.However,muchlessisknownaboutresponsesbyspeciesthatexperiencemoresubtlechangesinseasonalweather.Wemonitoredambienttemperatures(Ta)andskintemperatures(Tsk)ofindividualsfrom3populationsofNewZealandlessershort-tailedbats(Mystacinatuberculata)usingtemperaturetelemetry.RelativetotheNorthIsland(NI),meansummerTawas1°ClowerintheSouthIsland(SI),yetSIindividualsusedtorporon36%ofobservationdayscomparedto11%forNIbats.Noneoftheweathervariableswerecordeddifferedbetweenthedaysbatsdid,ordidnot,usetorpor.Solitaryroostswereoccupiedon17%ofobservationdaysforNIpopulationsand38%forSIpopulations,withindividualsoccupyingthemexclusivelywhileusingtorpor.RelativetotheNI,meanwinterTawashigherinLittleBarrierIsland(LBI).BatsinLBIuseddailytorpormore(51%)thanintheNI(33%).FurthermoreinLBI,butnottheNI,batsweremorelikelytoarouseonnightswithwarmersunsetTa.InLBIbatspreferredthermallylabileroostsandpreferentiallyroostedinsidedeadpunga/silverfern-tree(Cyatheadealbata)whichcontrastswithNIindividualswhichprefermorethermallystabletreecavities.PungaroostthermalcharacteristicswerenodifferentthanTaallowingforindividualstopotentiallytakeadvantageofpassiverewarming.OurresultsprovideevidencethatevensmalldifferencesinTadifferentiallyimpactpopulations.Site-specificenergeticstrategiesareapparentbetweenM.tuberculatapopulationsduringsummerandwinter,demonstratingthatclimateaffectsbothroostchoiceandtorporpatterns.Clearlypopulationsinwarmerclimatesareunderlessenergeticstressandusesite-specificadaptationsdemonstratingthatclimateaffectsbothroostchoiceandtorporpatterns.
ANZSCPB2016 35
Dohamstersbask?
FritzGeiser1,2,KristinaGasch2,ClaudiaBieber2,GabrielleL.Stalder2,HannoGerritsmann2andThomasRuf2,
1Zoology,UniversityofNewEngland2WildlifeEcology,UniversityofVeterinaryMedicineVienna
Baskingcansubstantiallyreducethermoregulatoryenergyexpenditureofmammals.Wetestedthehypothesisthatthelargelywhitewinterfurofhamsters(Phodopussungorus),originatingfromAsiansteppes,mayberelatedtocamouflagetopermitsunbaskingonornearsnow.Winter-acclimatedhamstersinourstudywerelargelywhiteandhadahighproclivitytobaskwhenrestingandtorpid.Restinghamstersreducedmetabolicrate(MR)significantly(>30%)whenbaskingatambienttemperatures(Ta)of~15and0°C.Interestingly,bodytemperature(Tb)alsowassignificantlyreducedfrom34.7±0.6°C(Ta15°Cnotbasking)to30.4±2.0°C(Ta0°Cbasking),whichresultedinanextremelylow(<50%ofpredicted)apparentthermalconductance.Inducedtorpor(foodwithheld)duringrespirometryatT¬a15°Coccurredon83.3±36.0%ofdaysandtheminimumtorporMRwas36%ofbasalMRatanaverageTbof22.0±2.6°C;movementtothebaskinglampoccurredatTb<20.0°C.Energyexpenditureforrewarmingwassignificantlyreduced(by>50%)duringradiantheat-assistedrewarming,however,radiantheatpersewithoutanendogenouscontributionbyanimalsdidnotstronglyaffectmetabolismandTbduringtorpor.Ourdatashowthatbaskingsubstantiallymodifiesthermalenergeticsinhamsters,withadropofrestingTbandMRnotpreviouslyobservedandareductionofrewarmingcosts.Theenergysavingsaffordedbybaskinginhamsterssuggestthatthisbehaviourisofenergeticsignificancenotonlyformammalslivingindesertswherebaskingiscommon,butalsoforP.sungorusandlikelyothercold-climatemammals.
ANZSCPB2016 36
Brightnights,costlymornings:night-timebodytemperatureincreasescorrespondwithmoonphaseandcloudlessnightsinwinteringBarnacleGeese(Brantaleucopsis)
StevenPortugal
BiologicalSciences,RoyalHollowayUniversityofLondon
Itiswellknownthatanimalsrespondtofluctuationsinlightlevels,withdistinctcircadianrhythmsapparentinphysiologicalparameterssuchasheartrate(fH)andbodytemperature(Tab).WedeployedimplantabledataloggersthatcontinuouslyrecordfHandTab,in7wildbarnaclegeese(Brantaleucopsis)winteringinsouth-westScotland.ThegeesehadadistinctcircadianrhythminfHandTab,withnight-timevaluesbeing,onaverage,25beatsperminand2.5oClowerforfHandTabrespectivelywhencomparedtoday-timevalues.Furthermore,wehaveidentifiedrhythmicnight-timepeaksinTab,withincreasesof1.5oCabovenormalnight-timevaluesoccurringinthemiddleofthenightatregularintervalsthroughoutthewinterperiod.Thesenight-timepeaksinTabcoincidedwithspecificphasesofthemoon,illuminationlevelsandcloudcover.Upondawn,restingfHwassignificantlyhigherduringthesemorningsfollowingtheincidencesofnight-timepeaksinTabthanthosenightswherenonight-timepeakinTaboccurred.Thissuggestsa‘hangovereffect’ofthesenight-timepeaksinTab,whichwillhaveconsequencesfordailyenergybudgets.Itisapparentthatcircadianrhythmsinphysiologicalparameterscanbedisruptedbynaturaloccurrencesaswellasartificiallightsources.
ANZSCPB2016 37
Post-firerecoveryofthebehaviourandphysiologyofasmallmarsupial
ClareStawski1,TaylorHume1,GerhardKörtner1,ShannonE.Currie1,2,JuliaNowack1,3andFritzGeiser1
1CentreforBehaviouralandPhysiologicalEcology,Zoology,UniversityofNewEngland,Armidale2DepartmentofZoology,FacultyofLifeSciences,Tel-AvivUniversity,Tel-Aviv6997801,Israel3ResearchInstituteofWildlifeEcology,DepartmentofIntegrativeBiologyandEvolution,UniversityofVeterinaryMedicineVienna,Savoyenstrasse1,1160Vienna,Austria
Theinitialandshort-termeffectoffireisoftenadramaticchangeoftheenvironment,however,burnthabitateventuallyrecovers.Howanimalsrespondbehaviourallyandphysiologicallytosuchenvironmentalchangesispoorlyunderstood.Ourworkhasshownthatafteraprescribedfire(post-fire)femalebrownantechinus(Antechinusstuartii)spentsignificantlylesstimeactivethanbeforethefire(pre-fire)andindividualsinanunburntcontrolarea(control).Thisreductionintotalpost-fireactivitybyantechinuswasmadeenergeticallypossiblebyincreasingthedurationoftorpor—ahighlyefficientenergyconservationmechanism—andalsobydecreasingdailyminimumbodytemperatureincomparisontopre-fireandcontrolindividuals.Wehypothesisedthatasvegetationandfoodresourcesrecover,thebehaviourandphysiologyoftheantechinuspopulationwouldreturntonormal.Therefore,wequantifiedtheactivityandtorporpatternsofantechinusatthesametimefromthreegroups:i)theareaoftheprescribedfireoneyearpost-fire,ii)anareathatburnedtwoyearspriorandiii)thecontrolarea.Whileafteroneandtwoyearsgroundcoverintheareasoftheprescribedburnswasstillpatchyincomparisontothecontrolarea,ithadrecoveredsubstantially.Importantly,thedurationofactivityofantechinusinallthreegroupswassimilartothatmeasuredpre-fireandinthecontrolareathepreviousyear.Further,torporfrequency,torporboutdurationanddailyminimumbodytemperatureinallthreegroupshadalsoreturnedtovaluessimilartothoserecordedtheprecedingyearinthepre-fireandcontrolareas.Therefore,ournewresultsshowthat,inthecaseofalowintensityburn,onlyoneyearpost-fireantechinusresumednormaldailyactivityandtorporpatterns,likelyinresponsetothereturnofgroundcoverandincreasedforagingopportunities.
ANZSCPB2016 38
Controlofevaporativewaterlossbyaheterothermicdasyuridmarsupial
ChristineCooper1andPhilipWithers2
1DepartmentofEnvironmentandAgriculture,CurtinUniversity,Perth,WesternAustralia2AnimalBiology,UniversityofWesternAustralia,Perth,WesternAustralia
Wehaverecentlyrecognisedthatendothermicmammalsandbirdsappeartoregulatetheirinsensibleevaporativewaterlossindependentofexternalfactorswhichwouldbeexpectedtoperturbevaporationfromtheskinorlungs.Observationsofthisphenomenonforbothmarsupialandplacentalmammals,andforbirds,suggestsitisafundamentalcharacteristicofendothermicanimals,andwehypothesisethatitmaybeanimportantaspectofthermoregulation.Hereweexaminetheimpactofambienttemperatureandrelativehumidityontheevaporativewaterlossofaheterothermicdasyuridmarsupial,thered-tailedphascogale(Phascogalecalura),tocharacterisethisregulatoryresponseinaseconddasyuridspecies,andimportantlytoquantifytheimpactoftorporoncontrolofevaporativewaterloss.Normothermicphascogalesmaintainedinsensibleevaporativewaterlossindependentofambientrelativehumidityatambienttemperaturesof20,25and30°C,atleastathumidities≤60%.Therewasstrongstatisticalevidencethattheirevaporativewaterloss,correctedforwatervapourpressuredeficit,differedfromtheexpectedbiophysicalpatternatambienttemperaturesof20°Cand30°C,butnot25°C.Phascogalesenteredtorporatambienttemperaturesof20and25°Candtorporfrequencywasnotinfluencedbyambienthumidity.Phascogalesregulatedtheirevaporativewaterlossagainsttheexpectedbiophysicaldriversofevaporationduringtorporat20°C,butnotat25°C.Controlofevaporativewaterlossregulationamongstdasyuridmarsupialsisclearlynotjustacharacteristicofhyper-aridadaptedspecies,andismaintained,orevenenhanced,duringthermoregulatoryphasesoftorpor.However,itmaynotoccurwhenheterothermicspeciesarethermoconforming,providingsupportforthehypothesisthatinsensibleevaporativewaterlosscontrolservesathermoregulatoryroleforendothermicanimals.
ANZSCPB2016 39
Ontogeneticscalingoffemoralbloodrateinwesterngreykangaroo(Macropusfuliginosus),easterngreykangaroo(Macropusgiganteus)andredkangaroo(Macropusrufus)
QiaohuiHu,RogerS.SeymourandEdwardP.Snelling
DepartmentofBiologicalSciences,AdelaideUniversity
Anutrientartery,whichpassesthroughaforamenlocatedonafemurshaft,suppliesmorethanhalfofthetotalbloodsupplytothefemur.Nutrientforamensizecorrelateswitharterysize,thusfemoralbloodflowcanbeestimatedbymeasuringtheforamenarea.Interspecificfemoralbloodflowhasbeensuggestedtobeproportionaltotheanimals’locomotionlevelsinpreviousnutrientforamenstudies,butnostudyhaslookedintointraspecificfemorabloodflowofanimals.Thisstudydeterminedontogeneticfemoralbloodflowrateinthreespeciesofdiprotodontmarsupials,whicharewesterngreykangaroos(Macropusfuliginosus),easterngreykangaroos(Macropusgiganteus)andredkangaroos(Macropusrufus).Abiphasicrelationshipisrevealedforthescalingofwesterngreykangaroofemoralbloodflowduringontogeny,withasteepexponentof0.97±0.10,andthenashallowexponentof-0.49±0.94.Thebreakpointmatchesthepouchexitbodymass(ca.4-5kg).Growthrateissuggestedtobethemaindrivingfactorforintraspecificfemoralbloodflowduringkangaroos’in-pouchstateofdevelopment,whereasthemaindrivingfactorgraduallychangesfromgrowthratetolocomotionlevelasthekangaroosleavethepouch,andbecomemoreactive.Thereisnosignificantdifferenceinfemoralbloodflowbetweenthetwosexesofkangaroosduringin-pouchstage,butpost-pouchmalekangaroohavehigherfemoralbloodthanthefemalesbecauseoftheirhighergrowthrateandactivitylevels.
ANZSCPB2016 40
Quantifyingtheinfluenceofphysiologyandbehaviouronreptilianevaporativewaterlossrates
EliaPirtle1,ChristopherR.Tracy2andMichaelR.Kearney1
1UniversityofMelbourne2CaliforniaStateUniversityFullerton
Globalclimatechangeisexpectedtocausesignificantthermalstressforectothermicspecies,potentiallyresultinginextinctions.Anothersignificantsourceofstressmaybethechangesinprecipitationandaridityassociatedwithtemperaturechanges,theeffectsofwhicharepoorlyunderstood.Despitethestrongphysicalconnectionsbetweentemperatureandwaterdynamics,thetwoareoftenconsideredindependently.Moreover,thepotentialforregulatorybehaviourstomitigatetheeffectsofclimatechangesareoftenoverlooked:inparticular,reptilianbehaviouralhydroregulation.Ibeginbypresentingapredictivemodelofamajorcomponentofreptilianwaterbudgets:evaporativewaterlossrates.Thismodelisvalidatedbycomparingpredictionsofwaterlossratestomeasuredvaluesfor39squamatespecieswithseparatedcutaneousandrespiratorywaterlossratemeasurements.NextIpresentaquantitativeanalysisoftheadaptivesignificanceofseveralformsofphysiologicalandbehaviouralhydroregulationontheevaporativewaterlossratesoftwospeciesofcloselyrelatedyetecologicallydistinctAustralianskinks.Thisapproachpredictsananimal’sresponsestodifferentenvironmentalconditionsbycombiningamicroclimaticmodelwithamechanisticheatandwaterbudgetmodelthataccountsforbothphysiologicalconstraintsandregulatorybehaviours.Ifindthatbothphysiologicalandbehaviouralhydroregulatorymechanismscaninfluencewaterbudgetssubstantially,withsomebehaviouralmechanismspotentiallyreducingevaporativewaterlossratesbyover70%.Moreover,theamountofwaterthatcanbesavedthrougheachhydroregulatorymechanismvariesgreatlyacrossphysiology,behaviourandlifestyle,suggestingthattheabilitytocopewithchangingclimatesmayalsovarygreatlybetweenspecies.Understandingthesevariationswillimproveourabilitytoidentifyspeciesmostatrisk.
ANZSCPB2016 41
Livingwithaleakyskin:Upregulationofiontransportproteinsduringsloughing
NicholasWu,RebeccaL.CrampandCraigE.Franklin
TheUniversityofQueensland
Amphibianskinisamultifunctionalorganprovidingprotectionfromtheexternalenvironmentandfacilitatingthephysiologicalexchangeofgases,waterandsaltswiththeenvironment.Inordertomaintainthesefunctionstheouterlayerofskinisregularlyreplacedinaprocesscalledsloughing.Duringsloughing,theoutermostlayeroftheskinisremovedinitsentiretywhichhasthepotentialtointerferewithskinpermeabilityandiontransport,disruptinghomeostasis.Inthisstudywemeasured,invivo,theeffectsofsloughingonthecutaneouseffluxofionsintoadsRhinellamarinakeptinfreshwaterconditions.Wealsomeasuredtransepithelialpotential,cutaneousresistance,activeiontransport,andthedistribution,abundanceandgeneexpressionofkeyiontransportproteinssodium-potassiumATPase(NKA),andtheepithelialsodiumchannel(ENaC)duringsloughing.Wehypothesisedthatduringsloughing,therewouldbeagreatereffluxofionsasaconsequenceofincreasedpermeabilityand/orviaareductionintheabundanceorexpressionofcutaneousiontransportproteins.TherewasasignificantincreaseinsodiumandchlorideeffluxduringsloughinginR.marina.However,althoughinvitroskinresistancedecreasedaftersloughing,activesodiumtransportincreasedcommensuratewithanincreaseinNKAandENaCproteinabundanceintheskin.Thesechangesinskinfunctionassociatedwithsloughingdidnotaffectthemaintenanceofinternalelectrolytehomeostasis.Theseresultssuggestthatduringsloughing,amphibiansactivelymaintaininternalhomeostasisbyincreasingcutaneousionuptakerates.
ANZSCPB2016 42
Experimentalevolutionofdispersal-relatedtraitsinamodelinsect:morphological,physiological,andbehaviouralresponsestospatialselection
PieterArnold1,PhillipCassey2andCraigWhite3
1SchoolofBiologicalSciences,TheUniversityofQueensland2UniversityofAdelaide3MonashUniversity
Dispersalabilityvariessignificantlyamongindividuals.Muchofthisvariationhasbeenattributedtodispersalsyndromes–suitesofcovaryingmorphological,physiological,behavioural,andlife-historytraits–whichcorrelatewithdispersalandinvasioninfree-livingpopulations.Atpopulationrangeedgesandinvasion-fronts,thesedispersal-relatedtraitsappeartobeevolvingthroughthespatialassortmentofphenotypes.Yetdespitetheapparentubiquityoftheseobservations,noexperimentalstudyhasattemptedtoreplicatetheevolutionofphenotypictraitsunderspatialassortmentondispersal.Weusedtheredflourbeetle(Triboliumcastaneum)inalaboratorydispersalsystemtoassesshowselectiveprocesses,forandagainstdispersal,affecteddispersal-relatedtraits.HereIwilldiscussourfindingsthatbodysizerapidlydivergedoversevengenerations–dispersersbecamesmallerandnon-dispersersbecamelarger–andthatdispersershadarelativelylowermetabolicrate.Smallindividualsweremoreenergeticallyandbiomechanicallyefficientatclimbing,andwerethereforetheonesthatdispersedmorereadily.Thevarianceindispersalrateandmovementwasmaintainedevenunderintensiveselectionforopposingdispersalbehaviours.Thissuggeststhatindividualsmaymaximisetheirfitnessbyproducingoffspringthatexhibitavarietyofdispersalbehaviours;ahypothesisthatisfurthersupportedbythelackofatrade-offbetweendispersalbehaviourandreproductivesuccess.
ANZSCPB2016 43
Doesaridityaffecthomerangesize?ThespatialecologyofAustralia'sdasyuridmarsupials
GerhardKörtnerandFritzGeiser
CentreforBehaviouralandPhysiologicalEcology,Zoology,UniversityofNewEngland,Armidale,NSW2351,Australia
WeinvestigatedrelationshipbetweenbodymassandhomerangesizeinAustraliancarnivorousmarsupials(Dasyuridae)andtestedwhetherthosespecieslivinginresource-poordesertenvironmentshaverelativelylargerarearequirementsthantheirmesiccounterparts.Themovementpatternsoftwosympatricspeciesofdesertdasyurids(bodymass16&105g)wereinvestigatedviaradio-telemetryduringwinterinAstreblaNP,Queensland.TheseresultswerecomparedwithpublishedrecordsforotherAustraliandasyurids.Overall,homerangesizeofdasyuridsscaledwithbodymasswithacoefficientof1.29,whichisconsiderablyhigherthanthatforbasalandfieldmetabolicrates.Inaddition,malesofespeciallythelargerspeciesoccupiedlargerhomerangesthanfemales,evenafteraccountingforthesizedimorphismthatiscommonindasyurids.Whileasimpleseparationofhonerangesizebetweenmesicandaridzonespecieswasnotstatisticallysupported,analternativemodelbasedonaverageyearlyrainfallandprimaryproductionwastestedandthisyieldedsignificantdifferences.OurstudythereforeindicatesthathabitatqualityaffectshomerangesizeinAustraliandasyurids,albeitthiseffectwasnotasstrongasanticipated.Therefore,alternativeavenuesforreducingenergyexpendituresuchasadjustmentsofpopulationdensityaswellastheuseofdailytorporandbasking,commonlyobservedindesertdasyurids(includingthetwostudyspecies),likelyplayarole.However,thesecanapparentlyonlypartlycompensatefortheonaveragelowerresourcedensityinaridhabitats.
ANZSCPB2016 44
ConservationphysiologyofAsiaticblackbears(Ursusthibetanus):MonitoringstressandbehaviourinbearsrescuedfrombilefarmsinVietnam
EdwardNarayan1,AsumiWillis1,CorinnevandenHoek1,MandalaHunter-Ishikawa2,RichardThompson2andTuanBendixsen2
1SchoolofAnimalandVeterinarySciences,CharlesSturtUniversity2AnimalsAsiaBearRescueCentre,Vietnam
Conservationphysiologyconcepts,toolsandknowledgecanhelpsolveconservationchallengesacrossabroadrangeoftaxabyunderstandingandpredictinghoworganisms,populationsandecosystemsrespondtoenvironmentalstressors.Asiaticblackbearpopulationsaredecliningin-situduetobearbilefarmingtosourcebileuseintraditionalmedicine.AnimalsAsiaisbattlingthisbarbarictradethroughthecoordinationofbearrescuefromfarmsandrehabilitationprogramsinVietnamandChina.Westudied16Asiaticblackbears(6males,10females)afterimmediaterescuefrombearbilefarmsintheQuangNinhprovince,Vietnam.ItwashypothesisedthatnewlyrescuedAsiaticblackbearswilldemonstrateahighnumberofstereotypiesandhealthproblems,andhighlevelsoffaecalglucocorticoidmetabolites(anon-invasiveindexofphysiologicalstress).Theseclinicalresponseswouldbeindicativeofthelong-termeffectsofphysicalandpsychologicalstressthatthebearshaveensuedonthebearbilefarms.Afaecalcortisolmetabolite(FCM)enzyme-immunoassaywasusedtoquantifyFCMlevelsoverastudyperiodof22weeks.ThekeyresultsshowedthatmeanFCMconcentrationsreducedsignificantlyoverthefirst22weekssincearrivalofthebearsatAnimalsAsia'sVietnamBearRescueCentre.Allbearsperformedatleastonestereotypyandhadatleastthreedifferenttypesofhealthissues.Headswayingandpacingwerethemostcommonstereotypiesperformedbythebearswhileskin,limb,musculoskeletal,dentalandbloodproblemsweremostprevalentinthegroupof16Asiaticblackbears.Inconclusion,ourresultsdemonstratethatphysiologicalstresscanbereducedwhenbearsarerehabilitatedintheVietnamBearRescueCentre.Theresultsalsoshowthatsomedegreeofstereotypicbehaviourandhealthproblemsmayhavebecomeinherentasaresultofchronicstress.
ANZSCPB2016 45
Effectsofbehaviouralandphysiologicaltraitsonreleasebehaviourforash-greymice(Pseudomysalbocinereus)
PhilipWithers1,LukeKealley1,ChristineCooper2,HarrietMills1andDominiqueBlache1
1SchoolofAnimalBiology,UniversityofWesternAustralia2DepartmentofEnvironmentandAgriculture,CurtinUniversity
Weexaminedpotentialrelationshipsbetweenbehaviouralandphysiologicaltraits,andpost-releasemovementanddispersalinthefield,fortheash-greymouse(Pseudomysalbocinereus)todetermineifwecanpredictpost-releasebehaviourofamammalfromeasily-measuredlaboratorytraits.Laboratorymeasuresofpersonalityforeachindividual,suchasexploratorybehaviour(openfield)andlearningcapacity(Barnesmaze),alongwithphysiologicalvariablessuchasfaecalstresshormonelevels(cortisol)andbasicenergetic,hygricandthermalvariables(metabolicrate,waterloss,bodytemperature,thermalconductance)weremeasured.Individualpersonalityandphysiologywasthencharacterisedusingvariousapproachestocombinethesedata,includingrawvariables,factoranalysis,behaviouralindicesandmixedmodelassessmenttodeterminethemostusefulapproachtoquantifythesetraits.Rawvariableswerethemostsuccessfulforcharacterisingindividualpersonalityandphysiology,andthereforewereusedtorelatelaboratoryphysiologyandbehaviour,andtorelatethesetofieldmovements.Therewerenointer-correlationsbetweenthelaboratoryfactorsforopenfield,Barnesmaze,physiologyorfaecalcortisollevels,suggestingthateachmethodologymeasuresquitedifferentindividualtraits.Theonlysignificantrelationshipoflaboratorymeasureswithfieldmovementwasfortheopenfield(rawvariables,P=0.001;rawvariablessignificantlycontributingtofactors,P=0.006),indicatingthatifanash-greymousemovesmoreinanopenfieldinthelaboratory,itwillmovemorewhenrelocatedintothefield.Weconcludethattheopenfieldbehaviouraltestisthemostlikelylaboratorypredictoroffieldmovementanddispersalforthissmallnativerodentaftertranslocation.
ANZSCPB2016 46
Dietgeneralisationandspecialisationinafreshwaterturtle(Emyduramacquarii)
KristenPetrov1,JamesVanDyke1,NatashaMalkiewicz1,JessicaLewis1,MichaelB.Thompson2andRicky-JohnSpencer1
1SchoolofScienceandHealth,WesternSydneyUniversity2UniversityofSydney
Animalsforagefordifferentfoodstomaximisetheirratesofenergyandnutrientuptake.Preyareselectedbasedontheirnutritionalvalues,butarealsoselectedbasedonhowcostlyafoodresourceistoobtain.Whenfoodresourcesarescarce,individualsmayshifttheirforagingstrategiestofocusmoreonabundantfoodresources,leadingtointraspecificvariationindiet.Asageneralistconsumer,thefreshwaterturtleEmyduramacquariiiscapableofutilisingdifferentfoodresourcesbasedonpreythatispresentandabundant.Becauseofitsgeneralistdiet,E.macquariiiscapableofexploitingandsurvivingindifferenthabitats.Mystudyexaminedspatialandtemporalvariationinthedietofafreshwaterturtlespecies(Emyduramacquarii)inwetlandsneartheMurrayRiver,Australia,todetermine1)ifpopulationsofE.macquariivaryintheirdietand/ordisplayintrapopulationvariationand2)whetherthedietofindividualE.macquariivaryovertime.Usingstableisotopesandgutcontents,Ideterminedwhetherindividualturtlesvariedintheirdietacrossdifferentwetlands.Ialsousedstableisotopestodeterminewhetherturtlesvariedintheirdietoverlong(6-12months)andshort(3-6months)timescales.Bothstableisotopeandgutcontentdatarevealedamong-wetlanddifferencesinthedietofE.macquarii,withindividualsfromsomewetlandsbeingmorecarnivorousandindividualsfromothersbeingmoregeneralist/herbivorous.Specifically,E.macquariithatwerecarnivorousappearedtobestrictlycarnivorous,whilethegeneralist/herbivorousE.macquariiconsumedanimalsopportunistically.ThedegreeofherbivoryofE.macquariiwasdirectlycorrelatedwithincreasingplantabundance,butinverselycorrelatedwithwaterclarity.TheseresultssuggestthatE.macquariiconsumeamoregeneralist/herbivorousdietwhenplantsareavailable,butadoptamorespecialisedcarnivorousdietwhenvegetationislessabundant.HabitatanddiversityofavailablepreyconstrainthedietofE.macquarii,howeverE.macquariiappeartorespondbyshiftingtheirforagingstrategyfromgeneralisttofunctionallyspecialist.
ANZSCPB2016 47
Themechanisticbasesformaternaleffectsinturtles
JamesVanDyke,MichaelKelly,KristenPetrov,FionaLoudonandRicky-JohnSpencer
SchoolofScience&Health,WesternSydneyUniversity
Maternaleffectsarethenongeneticinfluencesmothershaveonoffspringphenotype.Theyincludenestsitechoice,eggbrooding,genomicimprinting,andthenutrientsandhormonesmothersallocatetotheireggs.Thenutrientsmothersallocatetotheiryoungdependnotonlyonthemechanismsunderpinningreproductiveallocation,butalsoonthenutritionalresourcesavailabletoherduringreproductiveallocation.Weusedawell-studiedsetofpopulationsofdecliningMurrayRiverShort-neckedTurtles(Emyduramacquarii)toinvestigatethemechanisticcausesofmaternaleffectsinoviparousvertebrates.Emyduramacquariiisageneralistthatconsumesgreenalgae,aquaticplants,periphyton,aquaticinvertebrates,fish,andcarrion.WestudiedE.macquariiinfourpopulationsinnorth-centralVictoriathatdifferinadultdiet.Weshowthatfemalesfromherbivorous/generalistpopulationsexhibithigherbodyconditionindicesthandofemalesfrommorecarnivorous,andpotentiallyfood-limited,populations.Theseconstraintscouldlimitthetotalamountofresourcesfemalescanallocatetoeggs,andthusconstrainreproductiveoutput.Theycouldalsoconstrainthespecificmacronutrientsthatfemalescanallocatetoyolk.Ourstudyaimstodeterminehowmaternaldietconstrainsarangeofreproductivevariableswithimplicationsforoffspringfitness.Wereportdifferencesinclutchsizeandeggsizethatmayindicatefoodconstraintsonreproductiveoutput.Theremainderofthestudyisinprogress,butweaimtotestforeffectsofpopulation-of-origin(diet)onthefollowingvariables:eggcomposition,embryometabolism,hatchingsuccess,hatchlinggrowthrate,hatchlingmetabolism,andhatchlinglocomotorperformance.Furthermore,becauseE.macquariieggandhatchlingphysiologydifferwithlayingorderwithinfemales,wealsoaimtodeterminehoweggcompositionvarieswithlayingorder.Inadditiontoadvancingknowledgeofmaternaleffects,ourresultsprovideinitialunderstandingofhowenvironmentalconstraintsonreproductiontranslatetofitnessimpactsonoffspringofadecliningspecies.
ANZSCPB2016 48
Evolutionofplasticity:mechanisticlinkbetweendevelopmentandreversibleacclimation
JulianBeaman1,CraigWhite2andFrankSeebacher3
1SchoolofBiologicalSciences,TheUniversityofQueensland2SchoolofBiologicalSciences,MonashUniversity3SchoolofLifeandEnvironmentalSciences,UniversityofSydney
Phenotypiccharacteristicsofanimalscanchangeindependentlyfromchangesinthegeneticcode.Theseplasticphenotypicresponsesareimportantforpopulationpersistenceinchangingenvironments.Plasticitycanbeinducedduringearlydevelopment,withpersistenteffectsonadultphenotypes,anditcanoccurreversiblythroughoutlife(acclimation).Thesemanifestationsofplasticityhavebeenviewedasseparateprocesses.Inarecentreview,wearguethatdevelopmentalconditionsnotonlychangemeantraitvaluesbutalsomodifythecapacityforacclimation.Acclimationcounteractsthepotentiallynegativeeffectsofphenotype-environmentmismatchesresultingfromepigeneticmodificationsduringearlydevelopment.Developmentalplasticityisthereforealsobeneficialwhenenvironmentalconditionschangewithingenerations.Hence,theevolutionofreversibleacclimationcannolongerbeviewedasindependentfromdevelopmentalprocesses.
ANZSCPB2016 49
LifeatlowpH:ThemechanisticbasisfortoleranceofextremelylowpHbyLimnodynastesterraereginaelarvae
RebeccaL.Cramp,EdwardA.MeyerandCraigE.Franklin
UniversityofQueensland
AquaticpHsbelow5.0aretoxictomostfreshwateranimals.Thistoxicityariseslargelythroughtheperturbationofionichomeostasis–lowpHdisruptsepithelialintegrityandcompromisesionuptakemachinery.Unusuallyforamphibians,embryosandlarvaeoftheAustralianfrog,LimnodynastesterraereginaecanhatchanddevelopinwateraslowaspH3.0makingthemoneofthemostacidtolerantvertebratesontheplanet.ThisstudyexploredthemechanisticbasisfortoleranceofextremelylowpHbylarvaeofL.terraereginae.LarvaewererearedfromembryosateitherpH3.5orcircumneutral(6.0-6.5).Branchialmorphologies,wholebodysodiumfluxesandepithelialiontransporterexpressionpatternswerecomparedacrosstreatments.LarvaerearedatpH6.5andacutelyexposedtopH3.5sufferedanetlossofsodiumasaconsequenceoftheinhibitionofsodiumuptake;effluxrateswerenotsignificantlydifferentfromthoseoflarvaerearedandtestedatpH6.5.However,larvaerearedandtestedatpH3.5sufferednonetlossofsodium,suggestingthatsodiumuptakemechanismsareplasticandcanacclimatetorestoresodiumhomeostasisinL.terraereginae.Comparedwithotheramphibianspecies,larvaeofL.terraereginaehaveaveryhighaffinitysodiumtransportsystemwhichmayallowthemtotakeupsodiumfromnaturallydilutewaters.However,thenatureofthetransportersresponsibleforsodiumuptakeinL.terraereginaeremainunclear.L.terraereginaelarvaerearedatlowpHareabletoresistthedamagingactionsofH+onepithelialjunctions,possiblythroughincreasedmucusproductionwhichservestocreateasemi-permeablebarrierbetweenthetissueandtheacidicenvironment.Takentogether,exploitationofextremelylowpHenvironmentsbylarvaeofL.terraereginaeappearstobeachievedthroughbothphysiologicalandmorphologicaladaptationswhichprotectbothsodiumuptakecapabilitiesandepithelialintegrity.
ANZSCPB2016 50
Hypoxiatolerantspeciestakeadvantageofintracellularacidosistomaintainmitochondrialfunction
JulesDevaux,AnthonyHickeyandCrystalJames
SBS,UniversityofAuckland
Fishinhabitenvironmentswithvariableoxygensupplies,inparticularforintertidalfishes.Problematically,hypoxiapromotesanaerobicmetabolism,lactateaccumulationandassociatedcellularacidosis.Thebrainisverysensitivetotheaccumulationofprotons,andthislikelyimpactshypoxicbrainmitochondria(mt).Whilemtconsumeoxygen(JO2)togeneratechemical(∆pH)andelectrical(∆)gradientsacrosstheinner-mt-membranestoproduceATP,theeffectsofextramitochondrialpHonbrainmtfunctionremainslargelyunexplored.Wepredictedthathypoxia-tolerantspecies(HTS)shouldbettertolerateacidosisthanhypoxia-sensitivespecies(HSS)intermsofbufferingcapacitiesandmtfunctionanddynamic.Usinghighresolutionrespirometrywetitratedlactic-acidtodecreaseextramitochondrialpH,andsimultaneouslyfollowJO2,∆m,H+bufferingcapacitiesandmtswellingofbrainmtwithinpermeabilisedbrainandisolatedmt.FourNewZealandtriplefinfishspecieswerecompared,eachwithdifferenthypoxia-tolerancesandrangingfromhighintertidaltosubtidalniches.WhileHTSandHSSdisplayedsimilarH+bufferingcapacities(~5mUpH.mg-1),contrastingresponseswerefoundformtfunction.InHSS4mMlactateelevatedJO2,yetdecreased∆mby~5%withamildacidosis(ΔpH-0.3)andmtweretotallyuncoupledmtatpH5.8.Incontrast,10mMlactate(ΔpH-0.6)induceda15%inhibitionofJO2inBellapiscusmedius,themostHTS.InB.medius∆remainedstableandcouplingcapacityatpH5.8wasmaintainedto30%ofthatatpH7.2.Overall,thesedataindicatethatintheHTSB.mediusdecreasedpHsupressesJO2yetmaintainsphopsphorylationintegritytoextremelylowpH.
ANZSCPB2016 51
Parentalenvironmentaffectsoffspring'sresponsestoUV-B
EnsiyehGhanizadehKazerouni1,FrankSeebacher1andCraigE.Franklin2
1SchoolofLifeandEnvironmentalSciences,UniversityofSydney,NSW2006,Australia 2SchoolofBiologicalSciences,UniversityofQueensland,St.LuciaQLD4072,Australia
Theparentalenvironmentplaysanimportantroleindeterminingtheabilityofoffspringtocopewiththeirenvironment.Suchdevelopmentalplasticityisbeneficialwhenparentalandearlydevelopmentalandlateroffspringenvironmentsarematched,butitcanbedetrimentalifthereisamismatch.UV-Bradiationdamagescellsdirectlyandbyincreasingreactiveoxygenspecies(ROS)formation.OuraimwastotestwhetherparentalexposuretoUV-BincreasesoffspringROSdefencemechanismtoreducethenegativeeffectsofUV-Binoffspring.Totestourhypothesis,weraisedjuvenileguppies(Poeciliareticulata)underUV-Bandcontrol(no-UV-B)conditionstomatureandbreed.Afterparturition,offspringfromeachparentalgroupweretransferredtoUV-Bandcontroltreatmentsandraisedtomaturity.OurresultsshowedthatexposingparentstoUV-BincreasedtheresilienceoftheiroffspringtothenegativeeffectsofUV-B.WhenexposedtoUV-B,offspringfromparentsalsoexposedtoUV-Bhadsignificantlygreatersustainedswimmingperformance,whichwasparalleledbyincreasedcatalaseactivityandglutathioneconcentrations,andreducedROSdamagetomembraneandproteins,comparedtooffspringfromcontrolconditions.However,parentalexposuretoUV-Bincreaseddamagetoproteinsandinfectionratesbywhitespotprotozoanincontroloffspring.TherewasnoeffectofparentalexposuretoUV-Bonoffspringsuperoxidedismutaseactivity,restingandactivemetabolicrates,oroffspringsize.WeshowedthatparentalexposuretoUV-BcanbebeneficialonlywhenoffspringwerealsoexposedtoUV-B.Thetrade-offbetweenthebeneficialeffectsofparentalexposuretoUV-BonoffspringalsoexposedtoUV-BenvironmentandtheincreasedsusceptibilitytoinfectioninoffspringnotexposedtoUV-Bcanbeimportantindeterminingtheresilienceofpopulationsinvariableenvironments.
ANZSCPB2016 52
IshypoxiatolerancereflectedinNewZealandTriplefinbrains?(Tripterygiidae):Analysingenzymeactivitiesandmetabolites
CrystalJames,AnthonyHickey,JulesDevaux,ChristopherHedgesandStewartMasson
UniversityofAuckland
Adultmammalianbrainsareextremelysensitivetoreducedoxygen,failingwithinminutesofanoxia.Hypoxiaenhancesanaerobicmetabolism,causingredoximbalance,andlactateandglutamateaccumulationwhichpotentiallyleadstoexcitotoxicityandcelldeath.Incomparison,someaquaticanimalsroutinelysurvivelevelsoflessthan3%atmosphericoxygen.WehavefoundthatNewZealandtriplefinfish,especiallyintertidalrockpoolspecies,arerobusttolowoxygenrepeatedlyexperiencinghypoxiaornearanoxia,whilemaintainingbrainfunction.Investigationsintomechanismsenhancingsurvivalofthebrainofthesefishshouldbeinformativeastohowhumanscouldincreasehypoxiatolerance(HT).
AspartofalargerprojectfiveNewZealandtriplefinspeciesrangingfromintertidal(experiencehypoxia)tosubtidalzones(donotexperiencehypoxia)wereinvestigatedastheyshowdifferentdegreesofHT.TwokeymechanismsthoughttobeimpactingHTwereexamined.Firstly,theactivityofkeyenzymeswasassessedtodeterminetheircontributionstooverallmetabolism.Thesecondmechanismtocomplimentthisisanalysisofabundanceinmetabolitesbetweenspeciessubjectedtoa20minutehypoxicevent.Enzymaticactivitywasdeterminedspectrophotometrically,whilstGasChromatography-Massspectrometry(GC-MS)wasusedtodetermineconcentrationsofkeymetabolites(sugars,organicacids,fattyacids,lipidsandproteins).PreliminarydatahasfoundthatanaerobicassociatedlactatedehydrogenaseactivitywassurprisinglylowerinHTspeciesthanhypoxiasensitivespecies(420±27&520±20umol/min-1/g-1respectively).However,HTspecieshad~22%greatercreatinekinaseactivitiescomparedtotheirhypoxiasensitiverelatives.Glutamatedehydrogenase,citratesynthase,malatedehydrogenase,andadenylatekinaseallshowednorelationshipbetweenenzymeactivityandHT.PrimaryresultsfromGC-MSshowhypoxiainfluencesmetaboliteabundanceamongspecies.OveralltheseresultssuggestHTspeciesmayhavedecreasedanaerobiccapacitiesintermsoflactateformation,butmaysustainhypoxicfunctionusingcreatinephosphatestores.
ANZSCPB2016 53
Synchronoushatchinginfreshwaterturtles:metabolicandendocrinemechanisms
JessicaK.McGlashan1,MichaelB.Thompson2,FredricJ.Janzen3,JamesVanDyke1andRicky-JohnSpencer1
1SchoolofScienceandHealth,WesternSydneyUniversity2SchoolofBiologicalSciences,TheUniversityofSydney3DepartmentofEcology,EvolutionandOrganismalBiology,IowaStateUniversity
Synchronoushatchingisaformofenvironmentallycuedhatching(ECH)whichallowsembryostoalterthetimeofhatchinginrelationtotheenvironmentthroughphenotypicplasticity.Synchronoushatchinginturtleshasevolvedtoreducevariationinincubationtimeandincreaseanindividual’schanceofsurvival.Eggpositionandthermalgradientsinanestalterdevelopmentalratesofembryos,andhavepotentialtocauseasynchronoushatchingtimes.Cuesfrommoreadvancedeggsstimulatelessadvancedeggstoeitherhatchearlyoracceleratedevelopmentthroughmetaboliccompensation.Hormoneslikelyplayacriticalroleinenablingmetaboliccompensationandearlyhatching.Thyroidhormonesandglucocorticoidsregulateembryogenesisandarevitalduringbirth/hatchingeventsinmanyspecies.Icomparedthemetabolicandendocrinemechanismsofhatchingsynchronyinfreshwaterturtles.Metaboliccompensationandchangesincircadianrhythmsenabledembryostoadjusttheirdevelopmentalratesandcatch-uptomore-advancedeggs.Hormoneanalysesindicatedtherewasnodifferenceintriiodothyronine(T3)andcorticosteroneconcentrationsduringasynchronousdevelopmentthusarenotresponsibleforstimulationofmetaboliccompensation.TherewashoweveraclearphysiologicalresponsetoexogenousT3applications,whichcausedneonatestohatchearlierthanexpectedbutwithnodevelopmentalormetaboliccosts.Triiodothyronineandcorticosteroneconcentrationsincreasedintheyolkofthedevelopingembryostowardstheendofincubationinbothasynchronousandsynchronousclutches,whichcoincideswithhatching.Thesehormonesmightnotregulatemetaboliccompensation,buttheyarelikelyimportantforsynchronoushatching.Synchronoushatchinghasevolvedindependentlyindifferentturtlelineagesandthespecificmechanismsutilisedtoachievesynchronoushatchingineachspecieslikelymaximiseanindividual’schanceofsurvival.ComparingthemechanismsusedtosynchronouslyhatchfurtherimprovestheunderstandingofthedifferentwaysinwhichECHhasevolvedinreptiles.
ANZSCPB2016 54
Regulatoryelementsthatdrivecorticotropin-releasinghormonereceptor2geneexpressioninavianthyrotropes
YugoWatanabe,BertDeGroefandSylviaV.H.Grommen
DepartmentofPhysiology,AnatomyandMicrobiology,LaTrobeUniversity
Inrepresentativenon-mammalianvertebrates,CRHhasapotentthyrotropin(TSH)-releasingeffectinadditiontoitscorticotropin(ACTH)-releasingeffect.Inchickens,theTSH-releasingactivitybyCRHismediatedbytype2CRHreceptor(CRHR2)inthethyrotropes(TSH-producingcells)ofthepituitarygland.However,itisnotknownwhetherCRHcontrolsTSHreleaseinotheravianspeciesthathavedifferentthyroidalactivityduringtheirlifecycle.Therefore,weinvestigatedtheTSH-releasingcapacityofCRHinanaltricialspecies,thezebrafinch(Taeniopygiaguttata).ThecellularlocalisationofCRHR2mRNAinthepituitarywasdeterminedbyinsituhybridisation,combinedwithimmunohistochemicalstainingofpituitarythyrotropes.OurstudyshowedthatCRHR2mRNAispresentinthezebrafinchthyrotropes,similartowhatwaspreviouslyfoundinchickenpituitary.Furthermore,isolatedzebrafinchpituitariesstimulatedwith100nMCRHshowedincreasedsecretionofTSH-likeactivityasmeasuredinathyroidbioassay.TheseresultssuggestthattheCRHR2expressedonthyrotropesareresponsibleforTSHreleasebyCRHinaltricialavianspecieslikeinprecocialspecies.WethenattemptedtoidentifytheregulatoryelementsinthegenepromoterofCRHR2inchicken.Sincetwotranscriptionfactors,Pit1andGATA2,determinethyrotropedifferentiationandmaintainexpressionoftheTSHβsubunit,wehypothesizedthatthethyrotrope-specificexpressionofCRHR2isalsogovernedbythesameregulatoryelementsandtranscriptionfactors.FragmentsoftheputativechickenCRHR2promoterwerefusedtotheluciferasereportergeneandco-transfectedwithPit1and/orGATA2expressionplasmidsintoCOS7ormurinethyrotrope-derivedTαT1cells.LuciferasereporterassaysshowedthatGATA2butnotPit1activatedtheCRHR2promoter.TheseresultsindicatethatCRHR2expressionisinducedbyGATA2activityasisthecasefortheTSHβgene,butincontrasttoTSHβ,themechanismdoesnotrequirePit1binding.
ANZSCPB2016 55
Doesthespottedgar,Lepisosteusoculatus,expressafunctionalendothelialnitricoxidesynthase?
MelissaCameron1andJohnDonald2
1SchoolofMedicalSciences,TheUniversityofSydney2SchoolofLifeandEnvironmentalSciences,DeakinUniversity
Theevolutionofendothelium-derivednitricoxide(NO)inbloodvessels,anditsassociatedsignallingpathway,remainscontentiousincomparativecardiovascularphysiology.TheadvancementofcomparativegenomicshasprovidedinsightintotheevolutionoftheNOsynthase(NOS)enzymes(NOS1,NOS2andNOS3),inparticularthatofNOS3thatisexpressedintheendotheliumofmammalianbloodvessels.Untilrecently,theparsimoniousviewwasthatNOS3evolvedearlyinthetetrapods,asallthreeisoformsarefoundinamphibians,butonlytwoisoforms(NOS1andNOS2)arefoundinthegenomesofteleostandchondrichthyanfishes.Recently,allthreeNOSproteinshavebeenpredictedinthegenomeofthenon-teleostactinopterygian,Lepisosteusoculatus,whichreshapesourunderstandingofNOS3evolution.Thisstudyaimedtocharacterisethenos3geneanddetermineifNOS3isafunctionalproteinwithinthevasculatureofL.oculatus.Thepredictednos3genedidnotdemonstrateaconservedsyntenywiththenos3geneofmouseandXenopusnos3,comparedtotheconservedsyntenythatisfoundfornos1andnos2.PhylogeneticanalysisshowedthatthepredictedNOS3proteingroupedwithothervertebrateNOS3proteins;L.oculatusNOS1andNOS2groupedwiththeirrespectiveisoforms.Toconfirmthegenomicsequence,wehavecloned57%oftheL.oculatusnos3mRNA,whichwasfoundtobe99%similartothepredictedsequence.WethendesignedaspecificL.oculatusNOS3antibody,anddemonstratedNOS3-immunoreactivityintheadventitiaofmanybloodvessels.TodetermineifthepresenceofNOS3withinthevasculaturecontributedtovasodilation,myographywasperformedonthedorsalaorta.Interestingly,additionoftheNOdonor,sodiumnitroprusside,hadnoeffectonvasculartone.Together,thesedatasuggestthatL.oculatusdoesexpressaNOS3proteinwithinthevasculature,butitdoesnotappeartocontributetovascularregulation.
ANZSCPB2016 56
TheroleofleptinandghrelininappetiteregulationintheAustralianSpinifexhoppingmouse,Notomysalexis,duringlong-termwaterdeprivation
JohnDonald1,NoorKhalidahAbdulHamid1andJanetMcLeod2
1SchoolofLifeandEnvironmentalSciences,DeakinUniversity2SchoolofMedicine,DeakinUniversity
Manymammalsliveindesertswheredrinkingwaterisabsentandsurvivebygainingpreformedand/ormetabolicwaterfromfoodandemployingasuiteofadaptationstoreducewaterloss.However,giventheimportanceoffoodasasourceofwater,littleisknownabouthowdesertmammalscanregulateappetitetoincreaseconsumptionofpreformedwaterandsubstrateformetabolicwaterproduction.IntheSpinifexhoppingmouse,Notomysalexis,waterdeprivation(WD)inducedabiphasicpatternoffoodintakewithaninitialhypophagiathatwasfollowedbyanincreased,andthensustainedfoodintake.Themicelostapproximately20%oftheirbodymass,andtherewasalossofwhiteadiposetissue.StomachghrelinmRNAwassignificantlyhigheratday2ofWDbutthenreturnedtothesamelevelsaswater-replete(day0)miceforthedurationoftheexperiment.PlasmaghrelinwasunaffectedbyWDexceptatday10whereitwassignificantlyincreased.Plasmaleptinlevelsdecreasedatday2andday5ofWD,andthenincreasedsignificantlybytheendoftheWDperiod.WaterdeprivationcausedasignificantdecreaseinskeletalmuscleleptinmRNAexpressionatdays2and5,butthenitreturnedtoday0levelsbyday29.Inthehypothalamus,WDcausedasignificantup-regulationinbothghrelinandneuropeptideYmRNAexpression,respectively.Incontrast,hypothalamicghrelinreceptormRNAexpressionwassignificantlydown-regulated.AsignificantincreaseinleptinreceptormRNAexpressionwasobservedatdays17and29ofWD.ThisstudydemonstratedthatthesustainedfoodintakeinN.alexisduringWDwasuncoupledfromperipheralappetite-regulatingsignals,andthatthehypothalamusappearstoplayanimportantroleinregulatingfoodintake;thismaycontributetothemaintenanceoffluidbalanceintheabsenceoffreewater.
ANZSCPB2016 57
SPEEDTALK
DNAdamageinducedbyultravioletradiationisrepairedfasterbyenzymaticphotoreactivationthanbynucleotideexcisionrepairinanamphibianspecies
LesleyA.Alton1,RebeccaL.Cramp2,EmmaCeccato2,FrankSeebacher3andCraigE.Franklin2
1SchoolofBiologicalSciences,MonashUniversity2SchoolofBiologicalSciences,TheUniversityofQueensland3SchoolofBiologicalSciences,TheUniversityofSydney
Ultravioletradiation(UVR)hasbeenanimportantenvironmentalstressorandselectionpressureforbiologicalorganismssincelifebegan.UVRabsorbancebyimportantmoleculeswithincellscaninitiatearangeofphotochemicalreactionsthatarebothdetrimentalandbeneficialtolivingorganisms;UVRcausesinjurytocellsbydamagingDNA,proteinsandlipids,butisalsonecessaryforvitaminDsynthesis,DNArepairandvision.AsaconsequenceofanthropogenicozonedepletiontheamountofdamagingUVRreachingthebiospherehasincreased.IncreasedUVRissuspectedtohavecontributedtotherapiddeclineofnumerousamphibianpopulationsaroundtheworld.ExposuretoUVRisknowntohavenegativeconsequencesforthehealthandsurvivaloftheembryosandtadpolesofseveralamphibianspecies.However,likeotherorganisms,amphibianshaveevolvedanumberofdefencesagainstthedamagingeffectsofUVR,includingtherepairofDNAdamage.Enzymaticphotoreactivation(EPR)andnucleotideexcisionrepair(NER)aretwoprocessesbywhichDNAdamagecanberepaired.TheefficacyofEPRisknowntovaryamongamphibianspeciesandisnegativelycorrelatedwithUVRsensitivity,butlessisknownofNER.HerewepresentourfindingsontherateofDNArepairbyEPRandNERintadpolesofthestripedmarshfrogLimnodynastesperonii.OurdatashowthatEPRisconsiderablymoreeffectiveatremovingDNAdamagethanNERinL.peroniiwith50%ofthedamagerepairedafter1.4hbyEPRand42hbyNER.WithoutEPRtorepairDNAdamage,tadpolesurvivalwassignificantlyreducedbetween18and24h,addingsupporttoourfindingthatNERisnotaneffectiverepairmechanisminthisamphibianspecies.
ANZSCPB2016 58
Thehypothalamo-pituitary-adrenalaxisinthefat-taileddunnart(Sminthopsiscrassicaudata),anAustralianmarsupial
EllyseNoy,MelissaScott,DianaRayment,SylviaV.H.Grommen,KylieRobertandBertDeGroef
DepartmentofPhysiology,AnatomyandMicrobiology,LaTrobeUniversity
Aswildlifemanagementdecisionscanbeinformedbytheunderstandingofhowananimalrespondstothreats,thestressphysiologyofthefat-taileddunnart(Sminthopsiscrassicaudata),anAustralianmarsupial,wasstudied.Likemostvertebrates,marsupialsrespondtostressorswiththeactivationofthehypothalamo-pituitary-adrenal(HPA)axis.Uponperceptionofastressor,thehypothalamusreleasescorticotropin-releasinghormone(CRH),whichstimulatestheanteriorpituitaryglandtosecreteadrenocorticotropichormone(ACTH)intothesystemiccirculation.Thishormone,inturn,stimulatestheadrenalcortextoreleaseglucocorticoids,theactualstresshormones.Wecloneddunnartprepro-CRHandtheACTHprecursorpro-opiomelanocortin(POMC)mRNAanddeterminedtheglucocorticoidresponsetorestraintstress.Restraintstresswasfoundtoeffectivelyinducearesponsewithin30minutes,withfreecortisollevelsincreasingmorethanthoseofcorticosterone,evenwiththecorticosteroneconcentrationsbeingmoreabundantinthecirculationinunstressedanimals.ThedunnartcodingsequencesofPOMCandprepro-CRHencodepeptidesof399and200aminoacids,respectively.WhiletheACTHandbeta-endorphinsequenceswithinPOMCarehighlyconserved,thePOMCsequenceshowssomeuniquefeaturesinthisspecies,andperhapsallAustralianmarsupials,includingthesecondarylossofagamma-melanotropinsequenceandduplicationsoftheACTHsequence,possiblyasaresultofaberrantcrossing-overevents.MaturedunnartCRHisidenticaltoCRHinhuman,mouse,ratandchicken,andasaconsequence,toolsusedtostudyCRHinthesespeciesarepredictedtoworkinthedunnartaswell.
ANZSCPB2016 59
Divinginawarmingworld:Environmentalandphysiologicaldeterminantsofdivedurationincrocodiles
CraigE.Franklin,EssieRodgers,LilyBentleyandRossDwyer
SchoolofBiologicalSciences,TheUniversityofQueensland
Temperaturehasapervasiveeffectonphysiologicalfunctionandorganismalperformance.Divedurationofectothermsisinfluencedbyphysiologicalresponsesandcapacitiesandhasbeenshowntobehighlythermallydependent,whereelevatedtemperaturescansignificantlyreducedivetimes.Giventhatdivingplaysasignificantecologicalroleincrocodiles,includingforagingandpredatoravoidance,understandingthepotentialeffectsofpredictedrisesinglobaltemperaturesonthiscriticalbehaviourisofinterest.Usingfielddataandtakinganexperimentalapproachweexaminedthethermalsensitivityofdivinginestuarinecrocodilesandexploredtheflexibilityandplasticityofphysiologicalsystemstobufferthenegativeimpactsofelevatedtemperaturesondiveduration.Crocodileswereexposedtolong-termthermaltreatments,designedtoemulatewatertemperaturesunderdifferentclimatechangescenariosandphysiologicalresponsesanddivecapacitiestested.Theabilityofcrocodilestomitigatetheeffectsoftemperatureondivingabilityviathermalphenotypicplasticityandcompensationwillbediscussed.
ANZSCPB2016 60
AnestimateofthewaterbudgetfortheendangerednightparrotofAustraliaunderrecentandfutureclimates
MichaelKearney1,WarrenP.Porter2andStephenA.Murphy3
1SchoolofBioSciences,TheUniversityofMelbourne2DepartmentofZoology,TheUniversityofWisconsin,Madison53706,USA3BushHeritageAustralia,Level1,395CollinsSt,Melbourne,VIC3000
Endangeredspeciesmanagementmustnowincorporatethepotentialeffectsofclimatechange,butthisisofteninthecontextoflimiteddata.TheendangerednightparrotwasrecentlyrediscoveredintheAustralianaridzoneandamajoreffortisunderwaytoensureitssurvival.Akeyquestionistowhatextentitisdependentonstandingwaterundercurrentandfutureclimates,asthishasmajorimplicationsforunderstandingandmanagingitshabitatrequirements.However,verylittleisknownaboutitsecologyandphysiology,anditsconservationstatusprecludesinvasiveecophysiologicalstudies.Hereweshowhowthemethodsofbiophysicalecologypermitstronginferencesaboutthisproblemwithminimaldata.Wedevelopedabiophysicalmodelofboththeparrotanditshabitatattheonlyknownsiteofoccurrence.Weusedallometrically-adjustedobservationsoftheknownphysiologyofacloselyrelateddesert-adaptedAustralianparrot,thebudgerigar,toinferunknownaspectsofthenightparrot’sphysiologicalresponses,togetherwithplumagemeasurementsfrommuseumspecimens.Wetestedthemicroclimatemodelagainstempiricaldataonmicrohabitattemperaturesandcomparedtheendothermmodelpredictionsagainstaninfra-redthermographofthebirditself.Wethenusedthemodeltopredictthefrequencywithwhichtheparrotwouldneedtofindstandingwaterundercurrentandfutureclimatesdependingonthewatercontentofitsfood.Ourfielddatashowthatairtemperatureinnightparrotroostsduringhighsummertypicallyexceedstheinferredrestingcoretemperature(38°C)andcanexceed45°C.Ourcalculationsimplythatnightparrotscanpersistondryseedduringwinterconditionswithoutexceedingdangerouslevelsofdehydration,butwouldneedaccesstowaterorsucculent(55%water)foodduringsummer.Airtemperatureatthesiteisprojectedtoincrease3°Cby2070,whichwouldleadtolikelylethal(22%ofbodymass)levelsofdailydehydrationinsomeyearsevenonsucculentfood,andwoulddramaticallyincreaseitsdependenceonstandingwater.Ourfindingshavesignificantimplicationsfortheconservationmanagementofthenightparrotandprovideguidanceforfutureresearchpriorities.
ANZSCPB2016 61
Stressorinteractionsshapeupperthermallimits
PippaKern,RebeccaL.CrampandCraigE.Franklin
SchoolofBiologicalSciences,UniversityofQueensland
Thevulnerabilityoforganismstoclimatewarmingcanbepredictedbyhowclosespeciesaretotheirupperthermallimits,andtheircapacityforplasticityinthistrait.Inadditiontotemperature,manybioticandabioticfactorscanalterthermaltoleranceandshapethesensitivityoforganismstorisingtemperatures.Importantly,ithasbeendemonstratedthatinteractiveeffectsbetweenmultiplestressorsshapephysiologicaltolerances.Assuchacclimationcapacityofupperthermallimitsshouldbeassessedinrelationtovariationinmultipleenvironmentalstressors.Ifcrosstolerancebetweenstressorsresultsinchangestoupperthermallimits,singlefactorstudiesmaypoorlypredictthermaltoleranceundernaturalconditions.Hereweexaminetheinteractiveeffectsoftemperatureandultravioletradiationontheupperthermallimitsoftadpoles(LimnodynastesperoniiandPlatyplectrumornatum)inthecontextofstableandfluctuatingtemperaturevariation.TemperatureandultravioletradiationhadinteractiveeffectsontheupperthermallimitsofL.peroniitadpolesinstabletemperaturecondition.Exposuretoultravioletradiationincreasedupperthermallimitsoftadpolesincoldtemperatures,butreducedupperthermallimitsofwarmacclimatedtadpoles.UnderfluctuatingtemperatureconditionsexposuretoultravioletradiationincreasedtheupperthermallimitsofP.ornatumtadpoles,butreducedupperthermallimitsunderstablemeantemperatures.Thesedatademonstratethatexposuretoultravioletradiationcanmodulatetheeffectsoftemperatureonupperthermallimits,andhighlighttheimportanceofassessingstressorinteractionswhenpredictingresponsestoenvironmentalvariation.Speciessurvivalinthefaceofclimatewarmingwillbedeterminedbytheinteractiveeffectsoftemperaturewithmultiplenaturalandanthropogenicfactors.
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Mitochondrialplasticityasadeterminantofsurvivingclimatechange
GillianRenshaw1,JulesDevaux2andAnthonyHickey2
1HypoxiaandIschemiaResearchUnit,SchoolofAlliedHealthSciences,GriffithUniversity2SchoolofBiologicalSciences,UniversityofAuckland
Thethermallimitofcardiacmitochondrialefficiencycouldbeamajordeterminantofspeciesdistribution(1).Theeffectsofhightemperatureonbrainmitochondriaislesswellexplored.Weexaminedtheeffectof6temperaturesonbrainmitochondrialfunctioninhomogenatesfromtwoOrectolobiformsharkswhichoccupyshallowreefflatsexposedtothermalstressduringsummerlowtidesand/orperiodicnocturnalhypoxia.Epaulettesharks(Hemiscylliumocellatum),canundergometabolicdepressionbutGreycarpetsharks(Chilloscylliumpunctatum)cannot,yetbothcanwithstandcomparableperiodsofanoxia.Wemeasuredtheeffectofeachtemperatureon:i)mitochondrialcouplingefficiency;ii)non-phosphorylatingprotonleakfrommitochondria;andiii)changesinsubstrateutilisationforcomplexIandcomplexII.
Highresolutionoximetrywithamultiplesubstrate-inhibitorprotocolrevealedthatforbothspecies:mitochondrialcoupling(efficiency)wasgreatestat25oC,andmaintainedat30oCbutwas25%lowerat37oCand50%lowerat40oC.Mitochondriainbothspeciesweretotallyuncoupledat45oC.
Despiteanexponentialincreasedinprotonleakastemperatureincreased,Epaulettemitochondriamaintainedtheirelectrontransportsystemincoupledmitochondriaat25-37oC,whileGreycarpetsharkmitochondriashoweda30%decreaseinmitochondrialefficiencyat37oCcomparedto25oC.ExaminationofsubstrateutilisationrevealedthatEpaulettesharkmitochondriahadamorestablecomplex1utilisationthanGreycarpetsharks,especiallyat37oC.
ThesetwospeciesofOrectolobiformsharksmaintainedmitochondrialcouplingefficiencyoverawiderangeofthermalchallengesbutfailedattemperatureshigherthantheycurrentlyencounterintheirnaturalenvironment.
1. Reference:Iftikaretal.,(2014)J.Exp.Biol.217,2348-2357.
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ListofSpeakersPresenter AbstractpagenumberAlton,Lesley………………………………………………………………………………………………………………………………57Arnold,Pieter…………………………………………………………………………………………………………………………….42Beale,Phillipa…………………………………………………………………………………………………………………………….33Beaman,Julian…………………………………………………………………………………………………………………………..48Bieber,Claudia…………………………………………………………………………………………………………………………..13Braz,Henrique…………………………………………………………………………………………………………………………..20Bromfield,Lisa…………………………………………………………………………………………………………………………..17Cameron,Melissa………………………………………………………………………………………………………………………55Cooper,Christine………………………………………………………………………………………………………………………38Cramp,Rebecca…………………………………………………………………………………………………………………………49Czenze,Zenon……………………………………………………………………………………………………………………………34Devaux,Jules……………………………………………………………………………………………………………………………..50Donald,John………………………………………………………………………………………………………………………………56Dudley,Jessica…………………………………………………………………………………………………………………………..19Franklin,Craig……………………………………………………………………………………………………………………………59Friesen,Chris……………………………………………………………………………………………………………………………..14Geiser,Fritz……………………………………………………………………………………………………………………………….35GhanizadehKazerouni,Ensiyeh…………………………………………………………………………………………………51Gomez-Isaza,Daniel…………………………………………………………………………………………………………………..31Hu,Qiaohui……………………………………………………………………………………………………………………………….39James,Crystal…………………………………………………………………………………………………………………………….52Jones,Karl………………………………………………………………………………………………………………………………….29Kearney,Michael……………………………………………………………………………………………………………………….60Kern,Pippa………………………………………………………………………………………………………………………………..61Khan,Mohammad……………………………………………………………………………………………………………………..22Koertner,Gerhard……………………………………………………………………………………………………………………..43Kong,Jacinta………………………………………………………………………………………………………………………………18Laird,Melanie……………………………………………………………………………………………………………………………23Martin,Nicolas………………………………………………………………………………………………………………………….16Masson,Stewart……………………………………………………………………………………………………………………….25McDonald,Elle…………………………………………………………………………………………………………………………..26McGlashan,Jessica…………………………………………………………………………………………………………………….53Narayan,Edward……………………………………………………………………………………………………………………….44Nelson,Thomas…………………………………………………………………………………………………………………………27Noy,Ellyse…………………………………………………………………………………………………………………………………58Petrov,Kristen……………………………………………………………………………………………………………………………46Pirtle,Elia…………………………………………………………………………………………………………………………………..40Portugal,Steve…………………………………………………………………………………………………………………………..36Renshaw,Gillian………………………………………………………………………………………………………………………..62Stawski,Claire……………………………………………………………………………………………………………………………37Swoap,Steve……………………………………………………………………………………………………………………………..32Tomlinson,Sean…………………………………………………………………………………………………………………………28Turbill,Christopher……………………………………………………………………………………………………………………15VanDyke,James………………………………………………………………………………………………………………………..47Watanabe,Yugo………………………………………………………………………………………………………………………..54White,Craig……………………………………………………………………………………………………………………………….24Withers,Philip……………………………………………………………………………………………………………………………45Whittington,Camilla………………………………………………………………………………………………………………….21Winwood-Smith,Hugh………………………………………………………………………………………………………………30Wu,Nicholas……………………………………………………………………………………………………………………………..41
ContactDetailsSurname Firstname Organisation EmailAlton Lesley MonashUniversity [email protected] Pieter UniversityofQueensland [email protected] Phillipa AustralianNationalUniversity [email protected] Julian UniversityofQueensland [email protected] Eduardo UniversityofWollongong [email protected] Claudia UniversityofVetMed,Vienna [email protected] Henrique UniversityofSydney [email protected] Bromfield Lisa WesternSydneyUniversity [email protected] Candice MonashUniversity [email protected] Melissa UniversityofSydney [email protected] Christine CurtinUniversity [email protected] Rebecca UniversityofQueensland [email protected] Zenon UniversityofAuckland [email protected] Terence UniversityofNewSouthWales [email protected] Jules UniversityofAuckland [email protected] John DeakinUniversity [email protected] Jessica UniversityofSydney [email protected] Else Paul UniversityofWollongong [email protected] Craig UniversityofQueensland [email protected] Chris UniversityofSydney [email protected] Fritz UniversityofNewEngland [email protected]
Ensiyeh UniversityofSydney [email protected]
Gomez-Isaza Daniel UniversityofQueensland [email protected] Christopher Hickey Anthony UniversityofAuckland [email protected] Qiaohui AdelaideUniversity [email protected] Madeline [email protected] Anthony UniversityofWollongong [email protected] Crystal UniversityofAuckland [email protected] Karl UniversityofAdelaide [email protected] Michael UniversityofMelbourne [email protected] Pippa UniversityofQueensland [email protected] Mohammad UniversityofSydney [email protected] Koertner Gerhard UniversityofNewEngland [email protected] Jacinta UniversityofMelbourne [email protected] Melanie UniversityofSydney [email protected] Lundsgaard Niclas Martin Nicolas UniversityofWollongong [email protected] Masson Stewart UniversityofAuckland [email protected] Elle WesternSydneyUniversity [email protected] Jessica WesternSydneyUniversity [email protected] Edward CharlesSturtUniversity [email protected] Thomas UniversityofAdelaide [email protected] Ellyse LaTrobeUniversity [email protected] Kristen WesternSydneyUniversity [email protected] Elia UniversityofMelbourne [email protected] Steve UniversityofLondon [email protected] Gillian GriffithUniversity [email protected] Claire UniversityofNewEngland [email protected]
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Swoap Steve WilliamsCollege [email protected] Michael UniversityofSydney [email protected] Sean CurtinUniversity [email protected] Christopher WesternSydneyUniversity [email protected] James WesternSydneyUniversity [email protected] Yugo LaTrobeUniversity [email protected] Koa MacquarieUniversity [email protected] Craig MonashUniversity [email protected] Philip UniversityifWesternAustralia [email protected] Camilla UniversityofSydney [email protected] Hugh UniversityofQueensland [email protected] Nicholas UniversityofQueensland [email protected]