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DINOSAURIAN PALAEOBIOLOGY: A NEWZEALAND PERSPECTIVE J.WIFFEN Wiffen,J. 1996 1220: Dinosaurianpalaeobiology: aNewZealandperspective.Memoirsof theQueenslandMuseum 39(3): 725-731. Brisbane. ISSN0079-8835. ThefirstknowndinosaurbonefromNew Zealand wasidentified from theLateCretaceous marine sandstones at the Mangahouanga Stream site in 1980 (Molnar, 1981). Since then isolated bones indicate that a variety ofherbivores and carnivores were present after the separationfromGondwana80-85millionyearsagountiltheirextinction.Thoughgeographi- cally polarinorigin, survival fora long periodon an island landmass suggests a temperate Q climate prevailed as New Zealand drifted north. New Zealand, Cretaceous, dinosaur, palaeoclimate,paleobotany, taphonomy. J. Wiffen, 138BeachRoad, Haumoana, Hawke'sBay, NewZealand, 5July 1996. The only dinosaur fossils so far found in New dry summers), with resulting surfaces worn by Zealand come from the Late Cretaceous running water. Maastrichtian-Campanian marine sediments in the Mangahouanga Stream fossil site, North Is- SIGNIFICANCE land, New Zealand. These bones represent a By and large the record of terrestrial life from tdeirvreersstreiadlilniofesafurromfMauensaozaonidcNtheewoZnelaylarnedc.orTdheoyf ealnscieewnhterNe.ewAcZiedalcoanndditisino'ntsapsrgoodoudceadsbtyhotsheefhriogmh includevertebraeandphalanges from2-3 species rainfall and extensive forestcover are thoughtto oftheropod, vertebrae(Fig. 1A)andaribfroman account for the generally poor fossil record ankylosaur, an ilium (Fig. IB) from an or- (Fleming, 1962). nithopod and a rib fragment (Fig. 1C) from a Consequently althoughthe numberofdinosaur & sauropod(Molnar, 1981;Wiffen Molnar, 1989; bones identified to date is small, they are sig- Molnar & Wiffen, 1994). nificant for several reasons: Thebonesarefoundinhardcalcareousconcre- 1)They show thatdinosaursinhabitedthis part tions, locallyderived fromtheupperlayersofthe of Gondwana prior to its separation from the Maungataniwha Sandstone. This was laid down Marie Byrd Land area of western Antarctica on the eastern coastline of ancient New Zealand (Stevens, 1985). in Campanian-Maastrichtian (Haumurian- 2) They are the first evidence that terrestrial Piripauan) times and is now exposedat theMan- vertebrates survived in New Zealand after its gahouanga Stream (Fig. 2). Isolated bones were separation from Gondwana,asopposedtohaving carried from the adjacent l—andmass by rivers arrived there by dispersal. probably in seasonal floods the larger bones 3)Thisistheonlyknown SouthernHemisphere dropped as the f—low slowed through lagoonal or region where dinosaurs lived on a small island, estuarine areas prior to burial in riverborne for up to 15-20 million years, until their extinc- debris in nearshore wave base deposits tion. (Crampton & Moore, 1990; Moore & Joass, Whatevolutionary changes, ifany, occurred in 1991; Wilson & Moore, 1988). Theyoccuralong tvhiersoenmfeonrtm,sininthteheabpsreenscuemaobflmyigsrtaattiiconissltaondNeenw- with fossils ofmarine origin. Zealand and with (presumably) decreased com- Thedescribedterrestrialbonesareeasilyrecog- petition, are not known. To date no unique fea- nised(Fig. 3)andwellpreserved, withdiagnostic tures have been seen to suggest morphological features. Soitseemslikelythatthebonesweren't changes or geographic or climatic adaptations: transported far from land to the site. When ex- however, considerably more complete fossil tracted from the rock, there is little apparent material is required to determine this. abrasive damage on the bone surface that oc- Although similar taxa have been found from curredpriortoburial. Mostofthedamage seen is this period in Antarctica (Hooker et al., 1991; recent, from exposure afterthe concretions have Hammer & Hickerson, 1994) no closely-related eroded out ofthe enclosing rock and split due to forms h—ave been detected, in spite ofthe variety temperature extremes (i.e., winter frosts and hot oftaxa ornithopod, sauropod and ankylosaur, 726 MEMOIRS OFTHEQUEENSLAND MUSEUM thisvolume)andasecondskull of the large ornithopod Mut- taburrasaurus (Molnar, this volume) from Queensland and a range of new Jurassic material from Antarctica (Hammer & Hickerson, 1994) suggest the early and widespread distribution of dinosaurs on the southern con- tinent. So a greater under- standing ofthedistributions of thesepolardinosaurs,andtheir relationships to those from New Zealand, should result when more becomes known aboutthese new discoveries. Thedifficultiesofclosecom- parisons with New Zealand dinosaur bones are due to the paucity of fossil material col- lected and identified to date, hence the difficulty in finding homologouselementsforcom- parison, as well as the dis- crepancy in geological age from most other Australasian /Antarctic sites. FLORAANDFAUNA The New Zealand marine fossilrecordis relativelygood, andtheMangahouangaStream site has contributed fossils to 9 both marine (Crampton & Moore, 1990; Glaessner, 1980; Feldmann, 1993; Wiffen—, 1981)andterrestrialrecords including (possibly fresh- FIG. 1. A, Articulated nodosaurian caudal vertebrae (CD 546) from the water\ turtles (Gaffnev oers MaungataniwhaSandstone,MangahouangaStream,inposterolateralobli- cornm iQflQi flvinp rentTles cqaumeevriae.w.CDT,heNsepweciZmeeanlaunndfoGretoulnoagtielcyalexScuerevdeeydCtohleldecetpitohn,ofLfoowceusroHfuttth.e \(V,^- \ 4A\nr\Wk*/'ifrfen &s \M/oilnlar&, Scale= lcm.B,Posteriorpartoftherightilium(CD529)ofadryosaur-like 198**)> a coleopteran (Craw ornithopod from the Maungataniwha Sandstone, Mangahouanga Stream. Watt, 1987) and a cockroach, Scale = 1cm. C, Fragment of sauropod rib (CD 542) from the Maun- whichisstillunderstudy(Fig.5). gataniwhaSandstone,MangahouangaStream. Scale=5cm. A considerable quantity of — fossil wood and plant material probablynodosaurian,dinosaurs thathavebeen has been collected as well and this is currently &identified from the Mangahouanga site (Molnar beingdescribedbyJ.LRaine.Theavailablefossil Wiffen, 1994): the ankylosaurid bones found by the British Museum are as yet undescribed. plant material (wood, leaves, seeds and cone Recent discoveries, which include a neoceratop- scales) is probably biased due toits prese—rvation sian, Timimus hermani and a possible ovirap- in shallow wave-base marine sediments with torosaur(Rich & Rich, 1994; Currieetal., 1996) only the tougher plant material surviving fromVictoria, new ankylosaurmaterial (Molnar, transportationbyrivertotheregionofdeposition. DINOSAURIANPALAEOBIOLOGY: ANEWZEALAND PERSPECTIVE 727 bivorous dinosaur population, which in turn provided the food forthe carnivorous dinosaurs. However, palaeobotanical evidence appears to be accumulating to support the view of a cold Australasian polar climate, i.e., dominant an- giosperms that were deciduous, dormant in periods of cold and darkness and dropping all theirleaves overa shortperiod to formleafmats & (Vickers-Rich Rich, 1993; Johnson, 1993), thoughPole(1993)suggeststhatthisisstillbased on scant evidence. If true, presumably the deciduous plants would have, to some extent, replaced the conifers. From a practical point of FIG.2.TheMangahouangaStreamfossilsite,showing view, suchadeciduous vegetation wouldseemto a concretion eroding from the Maunataniwha haveprovidedameagrewinterdietfortheactive, Sandstone. Dinosaurian, and other, boneshavebeen medium-sized dryosaur-like herbivorous recovered fromsomeoftheseconcretions. dinosaur, while having the larger herbivores (sauropods) dependent on foraging for and Howevereighttypes ofangiosperm leaves and browsing on fallen leaf mats to sustain life over several seed capsules have been recognised and prolonged periods ofdarkness and low tempera- a considerable amount ofpodocarp-li—ke foliage, tureseemsan unlikelyscenario. Howmuchnutri- similar to present-day material though ment could be derived from cold, semi-frozen, araucarian wood, leaves and cone scales fallen leaves alone does not appearto have been dominate the collections (Raine, 1990; calculated, but it was probably substantially Crampton, 1990). It is hoped that ultimately the lower than in still-attached leaves, because most study ofthis material, combined with pollen and nutrients are withdrawn from leaves before they sporesamples,willgiveaclearerindicationofthe are dropped. The feasibility ofsauropodsofeven botanical environment in which these dinosaurs modest proportions 'grazing' on such a leafmat survived. is unclear, and even the question of how sauropods supported themselves in more POLAR DINOSAURS? temperateclimates isunresolved(Ostrom, 1985). There is no evidence that herbivorous dinosaurs roamed New Zealand in large herds, as occurred WhileitisevidentthatNewZealand'sdinosaur oinfNboortthhhAemrebriviocraesatatnhdiscpaerrniiodv,oraensdwtohuelbdalhaanvcee population was subpolarin the geographic sense & been ultimately controlled on this island (Fig. 6) (Molnar Wiffen 1994), it is notreadily landmass by the quality, quantity, reproductive apparentthattheclimateandconditions in which they survived during the subsequent 15-20 mil- rate and availablity ofthe vegetation that formed lion years werepolarintheclimatic sense. Water the food supply. The deciduous vegetation does temperatures of 14.3°C are suggested from not appear to have been adequate to support the oxygen isotope studies by Stevens & Clayton known dinosaurs through a cold polar winter. (1971) and the marine record shows that Migration was not an option on this relatively plesiosaurs, mosasaurs andturtles werecommon small island landmass (Molnar & Wiffen, 1994). in offshore waters in the Late Cretaceous. On There is nothing in the dinosaur bones so far land, there is—evidence of continuous forest and identifiedfrom the Mangahouanga Stream siteto plant growth e.g., the Jurassic fossil forest at indicate dwarfism, as suggested for Victorian & Curio Bay, Southland, the plant beds at Port dinosaurs by Vickers-Rich Rich (1993): a use- Waikato, the lignite and plant fossils in both ful strategy if food resources or climatic condi- South and North Islands, material from Shag tions made hibernation necessary for survival. Point and Cretaceous material from Putarau, But hibernation forthe relatively large dinosaurs northwesternNelson, KaiparaHarbourandMan- (Allosaurus-slze theropods and medium-size gahouanga Stream (Bose, 1975; Edwards, 1926; sauropods) found in New Zealand seems unlike- Ettingshausen, 1891; Johnson, 1993; K—ennedy, ly. Even remaining stationary for long periods in 1993;Mildenhall, 1970;Stevens, 1985) which groups toconserve warmthwouldbeunlikelyfor would have been essential to maintain a her- dinosaurs of this large size, while laying down 728 MEMOIRS OFTHEQUEENSLAND MUSEUM DINOSAURIAN PALAEOBIOLOGY: ANEWZEALANDPERSPECTIVE 729 FIG.4.Pterosaurdistalulna(CD467)fromtheMaun- gatanwha Sandstone, Mangahouanga Stream. Scale = 1cm. and curling up to keep the extremities warm would be improbable and finding sufficient handy caves to accommodate a number of animals ofthissize unbelievable. Sothere are no obviousbehavioral strategiesforthedinosaursto have coped with acold polar winter, either. The difficulty of comparing the environment and dinosaurs from New Zealand and Australia arises from the difference in geological ages of rthaensgeedfirnoomsaJuurrafsasuincast.oTEhaerlAyusCtrreatlaicaenoudsi,nowshaiulres FIMGa.un5.gaFtosasniilwchoackSraonadcsht,onaeb,ouMta4ng3amhmoulaonngg,afSrtormeatmh.e wAuhsetrreaalsiathweasonsltyillknatotwanchebdonteosGfornodmwaNneaw, Tprheesehnet.ad was not found, but the right antenna (a) is Zealand are Late Cretaceous (Maastrichtian, 65- 70 mill—ion years) when New Zealan—d had been bered that Sphenodon punctatus was a New adrift and an isolated island for ap- Zealandresidentpriortoand sincethe separation proximately 15-20 million years after separation from Gondwana and that it apparently survived from Gondwana. It would appear that dinosaurs everything, including the Pleistocene ice ages eitheradapted to whateverclimatic changes they from around 2 million to 14,000 years ago: an encountered over their 15-20 million years of example ofenduranceovera longperiodoffluc- occupation or the climate on the New Zealand tuating temperature. Admittedly, the relatively landmass remained relatively stable and smallsizeandlowermetabolicrateoftheTuatara temperate. Doubtless even with a reasonably allowed it to hibernate using holes and tunnels stableandtemperatemaritimeclimate,asprobab- made by birds, or tree roots, for shelter. On the ly existed, there were times when temperatures other hand the Moas, flightless ratite birds of droppedorroseand—conditions wereunfavorable large proportions whose ancestors are also fordinosaurian life withsubsequentdecreases believed to have lived on New Zealand since it in population size and reproduction at that time, separated from Gondwana, would have had dif- such as occurs in the wild (and also with domes- ficulty in hibernating during the Ice Age, b—ut ticated) animals today, but so far as is known of survived until shortly afterthe arrival ofman insufficient magnitude to wipe out any species around 1,000 years ago. This in spite of their before the end ofthe Cretaceous. higher metabolic rates and hence increased sus- Aliving example ofthe resiliency that favours ceptibility to low temperatures and winter food long-term survival is the Tuatara (Sphenodon shortages. punctatus): toquoteVickers-Rich&Rich(1993), These are just two of a number of the forms 'this reptile can live in conditions down to 5°C which are known to have survived, regardless of r as long as it can sun itself. It must be remem- climaticchangesand turbulentgeologicalevents, FIG,3.A,PlesiosaurianvertebraeexposedinaconcretionattheMangahouangaStreamlocality.B,Pedalphalanx ofalargetheropodexposedinaconcretionatthislocality. Bothspecimensshow thecharacteristicstructureof fossilbone as itis seen inthe fieldand show how thebonecanbe easilyrecognised in situ. 730 MEMOIRS OFTHEQUEENSLANDMUSEUM dominated the forests in this region. The recovered dinosaur material shows no special adaptations to cold climates. However, the sur- vival ofTuataras and Moas through the climatic variations that occurred in New Zealandsinceits separation from Gondwana shows that both en- dothermicandectothermicformswerecapableof surviving here for long periods. There is no reasonto thinkthat dinosaurs werenotabletodo so, too. It is hoped that other New Zealand sites yield- ingMesozoicterrestrialfossilswillbefound,and that more material will add to what we already know and expand our understanding of dinosaurian life and survival here on New Zealand and our place in the evolution of Gondwanan dinosaurs. ACKNOWLEDGEMENTS FIG. 6. MapofLateCretaceousSouthernHemisphere IwouldliketothankMikePole,I.L.Danieland insouthpolarprojectionshowingthepositionofNew J.P. Lovis for information regarding Cretaceous Zealand(NZ). SP=South Pole. plant life in New Zealand, J.I. Raine forhis con- tinuing study of the Mangahouanga Stream site since New—Zealand's isolation 80-85 million plant fossils, and R.E. Molnar for his editorial years ago though, as yet, there is little fossil assistance. evidence oftheir long period ofresidence. So it is not unexpected that the—dinosaurs whetherec- LITERATURECITED tothermicorendothermic consideredby som—e tobethe mostsuccessfulformsoflifeonearth BOSE, M.N. 1975. Araucaria Haastii Ettingshausen were capable ofsurviving whatever changes oc- fromShagPoint,NewZealand.ThePaleobotanist Zcuerarleadndw.itEhsipnectiheailrlypearsiodthoefseoccchuapnagteisonsoefeNmetwo CRAMm2P2e:Tn7Ot6N-o8,f0.Jd.eS.po&sitMiOonORoEf,thPe.R.Ma1u9n8g9.atEannviirwohna- have been substantially less great than those un- Sandstone (Late Cretaceous), Te Hoe Riverarea, dergone during the Caenozoic. western Hawke's Bay, New Zealand. New Zealand Journal ofGeology and Geophysics 33: SUMMARY 333-348. CRAW, R.D. & WATTS, J.C. 1987. An Upper Although the New Zealand contribution of Cretaceous beetle (Coleoptera) from Hawke's dinosaur fossils is small at this stage, they do Bay.JournaloftheRoyalSocietyofNewZealand contribute to the overall knowledge ofdinosaurs 17: 395-398. from the southern supercontinent, theirdispersal CURRIE, P.J., VICKERS-RICH, P. & RICH, T.H. 1996. Possible oviraptorosaur (Theropoda, andtheirsurvivaluntiltheirworldwideextinction Dinosauria)specimens fromtheEarlyCretaceous attheendoftheCretaceous.Thefossilsshowthat Otway Group of Dinosaur Cove, Australia. Al- dinosaurs did inhabit New Zealand after it cheringa20: 73-79. separated from Gondwana early in the Cam- DANIEL, I.L., LOVIS, J.D. & REAY, M.B. 1989. A panian. They are the oldest evidence for ter- brief introduction on the Mid-Cretaceous restrial vertebrates in New Zealand, and are the megaflora ofthe Clarence Valley, New Zealand. only near-polar dinosaurs from the Southern Pp. 27-29. In Douglas, J.G. & Christophel, Hemisphere that lived on an island landmass. M.D.C. (eds) 'Proceedings of the Third Interna- TheclimateofNewZealandat thattimeseems tionalOrganisationofPaleobotanyConference'. (Melbourne). to have been temperate, judging from the EDWARDS, W.N. 1926. Cretaceous plants from dinosaurianandplantfossils.Someplantmaterial Kaipara. New Zealand. Transactions ofthe New suggests that leaves were dropped during the ZealandInstitute 56: 121-128. winter forming leaf mats although conifers, not FELDMANN, R.M. 1993. Additions to the fossil these deciduous forms, still appear to have decapod crustacean fauna ofNew Zealand. New DINOSAURIAN PALAEOBIOLOGY: ANEWZEALANDPERSPECTIVE 731 Zealand Journal ofGeology and Geophysics 36: MOLNAR, R.E. & WIFFEN, J. 1994. A Late 201-211. Cretaceous polar dinosaur fauna from New FLEMING, C.A. 1962. New Zealandbiogeography, A Zealand. Cretaceous Research 15: 689-706. paleontologist's approach.Tuatara 10: 53-108. OSTROM, J.H. 1987. Romancing the dinosaurs. The GLAESSNER, M.F. 1980. New Cretaceous and Ter- Sciences27: 56-63. tiarycrabs(Crustacea: Brachyura)fromAustralia POLE, M. 1992. Cretaceous macrofloras of Eastern and New Zealand. Transactions of the Royal Otago, New Zealand. Australian Journal of HAMMSoEcRie,tyWo.fRS.out&hAHusItCraKlEiaRS10O4N:,171W-.1J9.2.1994. A Botany40: 169-206. HOOKc81Er29eR98s1-,t.8ed3J.0AJd.n,inMooIsrLanuNirtEhRfo,rpooAmd.CAd.nitn&aorscSatEiucrQaU.fErSRocImiAent,hceeS.E2L.6aK4t.:e RAINECDf,a.rmCoJ.p.mbI.(eelMd1ls9a,)9n0Hg.'.GaJLe.hao,tloeoHugaCiaycrnwaeglataraScdoe,coSiutBesrt.eyWpal.oamfn.&tNmePMa.wiclrd1oZef1eno1ahs.lasalinIlldn,s CretaceousofWestAntarctica. AntarcticScience AAbnsnturaacltsC'o.nf(eGreeonlcoeg,icNaalpiSeorci1e9t9y0,ofPrNoegwraZmemaleaannd:d ISAACT3:,ah3o3Mr.1Ja-.3,3F2oM.rOmaOtRioEn,: tP.hRe.b&asalJOfAaScSie,s Yo.fJ.a1L97a1t.e SCARLLoEwTeTr,HuRt.Jt.).& MOLNAR, R.E. 1984. Terrestrial Cretaceous transgressive sequence, northeastern bird or dinosaur phalanx from the New Zealand New Zealand. New Zealand Journal ofGeology Cretaceous. NewZealandJournalofZoology 11: andGeophysics 34: 227-236. 271-275. JOHNSON, K. 1993. Ancient leaves write history of STEVENS, G. 1980. 'New Zealand adrift.' (A.H. & forests. National Geographic 148, 2 A.W. Reed: Wellington),442pp. (Pp. 226-231) ('Geographica' column: notpaginated) VICKERS-RICH, P. & RICH, T.H. 1993. Australia's KENNEDY, L.M. 1993. Palaeoenvironment of an polardinosaurs. Scientific American 269(1): 50- Huamaurianplantfossillocality,PakawauGroup, 55. MILDNE.NWH.ANLelLs,on.DT.hCesi1s9.76. Checklist of valid and WIFFENNe,wJ.Ze1a9l8a1n.dT.hNeefiwrstZLeaatleaCnrdeJtoaucrenoaulsotufrtGleesolforgoym MOLNTiPZAnperv.aaRalnl,as9in1addR-c,.9tpE6ilE..aoanrn1ttIs9nh8moSa1Vfc.ceiriAelotanfhd,eoeissnsPRo8.i:solasy&7ua7r-flC8rfr9orSe.mosomwceNiNleeletw,ywMZZo.eefaall(Naaennedddsw..) WIF19F8E&f9rN.oG,mAeoJnN.peh&UywpspMiZeecOrasLlC2aNr4n:Aedt.R2a9A,c3le-coR2hu.9esE9r..ionr1gn9ai8t81h.2o:pFi5or3ds-t5f9pr.toemroNseauwr 'GondwanaFive'. (A.A. Balkema: Rotterdam). Zealand. Geobios 22: 531-536. 1996, this volume.. Observations ofthe Australian WILSON,G.J.&MOORE,PR. 1988.Cretaceous-Ter- ornithopod dinosaur, Muttaburrasaurus. tiary boundary in theTe Hoe Riverarea, western MemoirsoftheQueenslandMuseum39(3): 639- Hawke's Bay. New Zealand Geological Survey 652. Records33: 34-37.

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