搜索
2211200211ACTAECOLOGICASINICAVol.22,No.11Nov.,2002,(,310036)::2001203227;:2001208230:(1979),,,E2mail:Chenhuili968@sohu.com:(24273033)(2611,20113217)(Rhabdophistigrinuslateralis),,,242730334510321727132610d,3719d33(1617%),(100%)(ö=016)1:1,;24273033,3333,33;,,33,:;;;;;TheEffectsofThermalEnvironmentsonDurationofIncubation,HatchingSuccessandHatchlingsTraitsinaColubridSnake,Rhab-dophistigrinuslateralis(Boie)CHENHui2Li,JIXiang(SchoolofLifeSciences,HangzhouNormalCollege,Hangzhou310036,Zhe2jiang,China).ActaEcologicaSinica,2002,22(11):18501858.Abstract:WeincubatedRhabdophistigrinuslateraliseggslaidby12femalesatconstant(24,27,30,and33)andfluctuating(mean=26.1,range=20113217)temperaturestoassesstheeffectsofthermalenvironmentsonincubationlength,hatchingsuccess,andhatchlingtraits.Eggswereincubatedatthesamemoisturelevel(2gwaterö1gvermiculite;producingapproximately212kPawaterpotentialindifferentthermalenvironmentsinplasticcontainers(250mm180mm70mm)thatwerecoveredwithaperforatedplasticmembrane.Eggswere1ö32buriedinthesubstrate,withthesurfaceneartheembryoex2posedtoairinsidethecontainer.Weweighedcontainersdailyand,ifnecessary,addedwatertothevermi2culitetocompensateforsmallevaporativelossesandwaterabsorbedbyeggs.Eggswereweighedat52dayintervals.Uponemergence,eachhatchlingwasweighed,examinedforlocomotorperformance,andthenkilledbyfreezingto-15forlaterstudies.Becauselocomotorperformanceishighlysensitivetochangesinbodytemperatureinreptiles,weconductedtrialsatconstantbodytemperatureof30.Bodytemperatureofhatchlingswascontrolledbyplacingtheminanincubatorat30.Locomotorperformancewasas2©1995-2004TsinghuaTongfangOpticalDiscCo.,Ltd.Allrightsreserved.sessedbychasinghatchlingsalongaroundracetrackofwhichthecircumferencewas1.92m,whichal2lowedverticalfilmingwithadigitalvideocamera.Videotapeswereexaminedfortime2specificnumberofstops,time2specificlocomotordistance,andmaximumcontinuouslocomotordistancetraveledwithoutstoppingduringtheentiretrial.Thefrozenhatchlingswerelaterthawedfordatacollection.Sexofhatchlingswasdeterminedbypressingonbothsidesofthetailbaseusingforcepsforthepresenceorabsenceofhemipenes.SVL(snout2ventlength)andtaillengthweremeasuredforeachhatchling.Aftertakingthemeasurements,eachhatchlingwasseparatedintocarcass,fatbodies,andresidualyolk.Thethreecomponentsweredriedinanovenat65toconstantmass,andthenweighed.Weextractednon2polarlipidsfromdriedsamplesinaSoxhletapparatusforaminimumof515husingabsoluteetherassolvent.Theamountoflipidsinasam2plewasdeterminedbysubtractingthelipid2freedrymassfromthetotalsampledrymass.Wedeterminedenergydensityofdriedsamplesusinganadiabaticbombcalorimeter.Ashinsampleswasdeterminedusingamufflefurnaceat700Cforaminimumof12h.AlldataweretestedfornormalityusingKolmogorov2Smirnovtest,andforhomogeneityofvariancesusingBartlett’stest.Logeorarc2sinetransformationswereperformedwhennecessarytosatisfythecondi2tionsforusingparametrictests.Weuselinearregressionanalysis,one2andtwo2factoranalysesofvariance(ANOVA),andone2andtwo2factoranalysesofcovariance(ANCOVA),whentheassumptionsofpara2metricanalysesweremet.Nonparametricanalyseswereusedwhentheseassumptionswereviolated.Throughoutthispaper,valuesarepresentedasmean1standarderror,andthesignificancelevelissetatA=0.05.Incubationlength,hatchingsuccessandtheincidenceofdeformedembryoswereaffectedbyincuba2tionthermalenvironments,andthesexratioofhatchlingswasnot.Incubationlengthdecreaseddramati2callyastemperatureincreased.Theaveragedurationofincubationat24,27,30and33was4510,3217,2713and2610d,respectively;thedurationofincubationatfluctuatingtemperaturesaveraged3719d.Hatchingsuccesswasthelowest(1617%)at33,butthehighestincidence(100%)ofdeformedem2bryoswasrecordedfromeggsincubatedatthistemperaturecomparedtoeggsincubatedinotherthermalenvironments.Theoverallsexratioofhatchlingsdidnotdifferfromequality.Exceptforthatmaleshadlongertailsthandidfemales,allotherexaminedhatchlingtraitsdidnotdifferbetweenbothsexes.Hatch2lingsfromeggsincubatedat24,27,30andfluctuatingtemperaturesdidnotdifferinanyoftheexaminedtraits.Hatchlingsfromeggsincubatedat33werelighterinmassandsmallerinsizethanthosefromotherincubationthermalenvironments,characteristicallyhavingsmallercarcassesbutlargerresidualyolks.Energyexpenditureforembryonicdevelopmentwashigherineggsincubatedat33thaninthoseincubatedinotherthermalenvironments.Hatchlingsfromeggsincubatedat33containedlowerquantitiesofashthandidthosefromotherincubationthermalenvironments,butheavierhatchedshellswererecordedfromeggsincubatedatthistemperature.Exceptforthosefromeggsincubatedat33,hatchlingsfromotherincubationthermalenvironmentsdidnotdifferinthemaximumlengthofcontinuouslocomotion,thelocomotordistanceperminuteandthenumberofstopsperminute.Takentogether,ourdatarevealthat(1)aprolongedexposureofeggsofR.tigrinusat33hasanadverseandpresumablylethaleffectonembryonicdevelopment,and(2)therangeofviableincubationtemperaturescanbewidenedwheneggsareincubatedatfluctuatingtemperatures.Keywords:Colubridae;Rhabdophistigrinuslateralis;egg;incubation;hatchling;locomotorperformance:100020933(200