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| Titel |
Changes in vegetation and climate as reflected in tooth enamel isotopes of Quaternary mammalian faunas from Indonesia |
| VerfasserIn |
Renee Janssen, Josephine Joordens, Dafne Koutamanis, Mika Puspaningrum, John de Vos, Natasja den Ouden, Jeroen van der Lubbe, John Reijmer, Oliver Hampe, Gareth Davies, Hubert Vonhof |
| Konferenz |
EGU General Assembly 2017
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| Medientyp |
Artikel
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| Sprache |
en
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| Digitales Dokument |
PDF |
| Erschienen |
In: GRA - Volume 19 (2017) |
| Datensatznummer |
250138702
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| Publikation (Nr.) |
 EGU/EGU2017-1810.pdf |
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| Zusammenfassung |
| Climate and sea level fluctuations play a dominant role in the Quaternary biodiversity
dynamics of Indonesia, with glacial-interglacial cycles affecting hydroclimate, vegetation,
and animal migrations. We analyzed the carbon (δ13C), oxygen (δ18O), and strontium
(87Sr/86Sr) isotopes of bovid, cervid, and suid teeth from several Pleistocene and Holocene
sites on Java and Sumatra, in order to refine reconstructions of the paleohabitats of these
faunas, gain more insight into their climatic background, and constrain their chronology. Our
carbon isotope data indicate that individual sites are strongly dominated by the presence of
either C3-browsers or C4-grazers. Herbivores from the Padang Highlands (Sumatra) and
Hoekgrot (Java) cave faunas were mainly C3-browsers, while the studied herbivores from
Homo erectus-bearing sites Trinil and Sangiran (Java) utilized an almost exclusive C4 diet.
The C4 signal of Trinil herbivores confirms that the Hauptknochenschicht (Trinil HK) was
deposited during glacial conditions, allowing us to hypothesize that it can be dated to
MIS 16, 14 or 12. We propose that the dominant vegetation signals in Indonesian
fossil sites, as revealed by δ13C data, reflect a glacial-interglacial contrast. The
scarcity of δ13C values typically indicating mixed C3/C4 feeding may indicate that the
transition between glacial and interglacial precipitation regimes was relatively abrupt.
The observed positive correlation between δ13C and δ18O values can be attributed
to the glacial-interglacial contrast between precipitation δ18O values, caused by
differences in monsoon intensity. The 87Sr/86Sr data show that the dominant C4 signal
observed in the Sangiran and Trinil herbivore faunas corresponds with roaming in a
variety of landscape settings, corroborating our hypothesis that the δ13C values are
representative of the overall C3/C4vegetation balance in these areas. These results provide a
framework that will allow interpretation of future isotope data from these and other fossil
sites in this region, including the isotopic composition of Homo erectus fossils. |
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