Publication:
Stable-isotope microprofiling of wombat tooth enamel records seasonal changes in vegetation and environmental conditions in eastern Australia

dc.contributor.author Fraser, Rebecca en_US
dc.contributor.author Grun, Rainer en_US
dc.contributor.author Privat, Karen en_US
dc.contributor.author Gagan, Michael en_US
dc.date.accessioned 2021-11-25T16:37:31Z
dc.date.available 2021-11-25T16:37:31Z
dc.date.issued 2008 en_US
dc.description.abstract We present the first high-resolution carbon and oxygen isotope profiles of carbonate in modern wombat (genera Vombatus and Lasiorhinus) tooth enamel and demonstrate that the carbon isotope ratios (δ13C) clearly preserve seasonal changes in diet and local environmental conditions. Our baseline study of δ13C in tooth enamel and bone collagen from wombats that inhabited semi-arid, savannah, temperate and alpine environments in eastern Australia documented an offset of 5.2±0.4‰ and 12.9±0.3‰ from the animal's diet, respectively. Marsupial wombats are obligate grazers, whose teeth grow continuously. Sequential microanalysis of δ13C and δ18O along the length of wombat incisors yielded a time-series of isotopic variation. The microprofiles of wombat tooth δ18O are highly variable between and within sites. Notwithstanding, the δ18O values were relatively high in wombat teeth from arid and semi-arid sites, and significantly lower in those from southern temperate and coastal regions. In contrast, the δ13C of wombat tooth enamel correlates well with the local environmental setting and the seasonality of C3 and C4 grass growth. In areas with marked seasonal changes in the proportions of winter C3 and summer C4 grasses, wombat microprofile δ13C values varied by up to 8‰. Importantly, at sites with predominantly C3 or C4 grasses all year, variations in microprofile δ13C values are small (b1.9‰), indicating that the relatively large seasonality in δ13C we observe in wombat teeth must be primarily controlled by changes in diet, rather than animal-specific factors. This study shows that microprofiling of δ13C in wombat incisors, in particular, provides a high level of isotopic detail which is not available from time-averaged isotope records from bone collagen, or bulk analysis of isotopes in tooth enamel. Wombat teeth are common in the Quaternary fossil record and, as such, they have the potential to be outstanding archives of palaeoecological information. For example the δ13C of fossil wombat teeth could be used to define the changing proportions of C3 and C4 grasses inwombat diets through the Quaternary, which in turn reflect changes in the seasonality of precipitation, summer temperatures, and possible ecosystem modification by human activities. en_US
dc.identifier.issn 0031-0182 en_US
dc.identifier.uri http://hdl.handle.net/1959.4/45643
dc.language English
dc.language.iso EN en_US
dc.rights CC BY-NC-ND 3.0 en_US
dc.rights.uri https://creativecommons.org/licenses/by-nc-nd/3.0/au/ en_US
dc.source Legacy MARC en_US
dc.subject.other Enamel en_US
dc.subject.other Stable isotopes en_US
dc.subject.other Palaeodiet en_US
dc.subject.other Palaeoecology en_US
dc.subject.other Marsupials en_US
dc.title Stable-isotope microprofiling of wombat tooth enamel records seasonal changes in vegetation and environmental conditions in eastern Australia en_US
dc.type Journal Article en
dcterms.accessRights metadata only access
dspace.entity.type Publication en_US
unsw.accessRights.uri http://purl.org/coar/access_right/c_14cb
unsw.description.notePublic Journal website: http://www.sciencedirect.com/science/journal/00310182 en_US
unsw.identifier.doiPublisher http://dx.doi.org/10.1016/j.palaeo.2008.08.004 en_US
unsw.relation.faculty Science
unsw.relation.ispartofissue 1-2 en_US
unsw.relation.ispartofjournal Palaeogeography, Palaeoclimatology, Palaeoecology en_US
unsw.relation.ispartofpagefrompageto 66-77 en_US
unsw.relation.ispartofvolume 269 en_US
unsw.relation.originalPublicationAffiliation Fraser, Rebecca, Research School of Earth Sciences, Australian National University en_US
unsw.relation.originalPublicationAffiliation Grun, Rainer, Research School of Earth Sciences, Australian National University en_US
unsw.relation.originalPublicationAffiliation Privat, Karen, Electron MIcroscope Unit, UNSW en_US
unsw.relation.originalPublicationAffiliation Gagan, Michael, Research School of Earth Sciences, Australian National University en_US
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