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Ediacara biota flourished in oligotrophic and bacterially dominated marine environments across Baltica.

ABSTRACT: Middle-to-late Ediacaran (575-541?Ma) marine sedimentary rocks record the first appearance of macroscopic, multicellular body fossils, yet little is known about the environments and food sources that sustained this enigmatic fauna. Here, we perform a lipid biomarker and stable isotope (?15Ntotal and ?13CTOC) investigation of exceptionally immature late Ediacaran strata (<560?Ma) from multiple locations across Baltica. Our results show that the biomarker assemblages encompass an exceptionally wide range of hopane/sterane ratios (1.6-119), which is a broad measure of bacterial/eukaryotic source organism inputs. These include some unusually high hopane/sterane ratios (22-119), particularly during the peak in diversity and abundance of the Ediacara biota. A high contribution of bacteria to the overall low productivity may have bolstered a microbial loop, locally sustaining dissolved organic matter as an important organic nutrient. These oligotrophic, shallow-marine conditions extended over hundreds of kilometers across Baltica and persisted for more than 10 million years.

SUBMITTER: Pehr K

PROVIDER: S-EPMC5935690 | biostudies-other | 2018 May

REPOSITORIES: biostudies-other

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Ediacara biota flourished in oligotrophic and bacterially dominated marine environments across Baltica.

Pehr Kelden K Love Gordon D GD Kuznetsov Anton A Podkovyrov Victor V Junium Christopher K CK Shumlyanskyy Leonid L Sokur Tetyana T Bekker Andrey A

Nature communications 20180504 1

Middle-to-late Ediacaran (575-541 Ma) marine sedimentary rocks record the first appearance of macroscopic, multicellular body fossils, yet little is known about the environments and food sources that sustained this enigmatic fauna. Here, we perform a lipid biomarker and stable isotope (δ15Ntotal and δ13CTOC) investigation of exceptionally immature late Ediacaran strata (<560 Ma) from multiple locations across Baltica. Our results show that the biomarke ...[more]

PMID: 29728614

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Ediacara biota flourished in oligotrophic and bacterially dominated marine environments across Baltica.

Publications

Ediacara biota flourished in oligotrophic and bacterially dominated marine environments across Baltica.

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