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1.
Zootaxa ; 5424(1): 116-126, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38480297

RESUMO

The rove beetle fauna (Coleoptera: Staphylinidae) (excluding the subfamily Silphinae) of the PlioceneofWillershausen (Lower Saxony, North Germany) is reviewed based on the type and other material of previously described or reported taxa, as well as two new specimens. Six subfamilies are represented in the deposit, with two subfamilial assignments considered tentative: Aleocharinae?, Micropeplinae, Oxytelinae, Paederinae, Staphylininae? and Tachyporinae. Pliosyntomium Korge, 1967 syn. nov. is placed as a junior synonym of PaederusFabricius, 1775. The following new combination is established: Paederusschmidti (Korge, 1967) comb. nov. All rove beetle fossils from Willershausen housed in theCollections of theGeoscienceMuseum, University of Gottingen.


Assuntos
Besouros , Animais , Fósseis , Alemanha
3.
Proc Natl Acad Sci U S A ; 113(28): 7739-44, 2016 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-27354522

RESUMO

The Paleocene-Eocene Thermal Maximum (PETM) is a remarkable climatic and environmental event that occurred 56 Ma ago and has importance for understanding possible future climate change. The Paleocene-Eocene transition is marked by a rapid temperature rise contemporaneous with a large negative carbon isotope excursion (CIE). Both the temperature and the isotopic excursion are well-documented by terrestrial and marine proxies. The CIE was the result of a massive release of carbon into the atmosphere. However, the carbon source and quantities of CO2 and CH4 greenhouse gases that contributed to global warming are poorly constrained and highly debated. Here we combine an established oxygen isotope paleothermometer with a newly developed triple oxygen isotope paleo-CO2 barometer. We attempt to quantify the source of greenhouse gases released during the Paleocene-Eocene transition by analyzing bioapatite of terrestrial mammals. Our results are consistent with previous estimates of PETM temperature change and suggest that not only CO2 but also massive release of seabed methane was the driver for CIE and PETM.


Assuntos
Apatitas/química , Mudança Climática , Esmalte Dentário/química , Fósseis , Gases de Efeito Estufa , Isótopos de Oxigênio/análise , Atmosfera/química , Dióxido de Carbono , Metano , Temperatura
4.
PLoS One ; 7(11): e49531, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23226212

RESUMO

BACKGROUND: The oxygen (δ(18)O) and carbon (δ(13)C) isotope compositions of bioapatite from skeletal remains of fossil mammals are well-established proxies for the reconstruction of palaeoenvironmental and palaeoclimatic conditions. Stable isotope studies of modern analogues are an important prerequisite for such reconstructions from fossil mammal remains. While numerous studies have investigated modern large- and medium-sized mammals, comparable studies are rare for small mammals. Due to their high abundance in terrestrial ecosystems, short life spans and small habitat size, small mammals are good recorders of local environments. METHODOLOGY/FINDINGS: The δ(18)O and δ(13)C values of teeth and bones of seven sympatric modern rodent species collected from owl pellets at a single locality were measured, and the inter-specific, intra-specific and intra-individual variations were evaluated. Minimum sample sizes to obtain reproducible population δ(18)O means within one standard deviation were determined. These parameters are comparable to existing data from large mammals. Additionally, the fractionation between coexisting carbonate (δ(18)O(CO3)) and phosphate (δ(18)O(PO4)) in rodent bioapatite was determined, and δ(18)O values were compared to existing calibration equations between the δ(18)O of rodent bioapatite and local surface water (δ(18)O(LW)). Specific calibration equations between δ(18)O(PO4) and δ(18)O(LW) may be applicable on a taxonomic level higher than the species. However, a significant bias can occur when bone-based equations are applied to tooth-data and vice versa, which is due to differences in skeletal tissue formation times. δ(13)C values reflect the rodents' diet and agree well with field observations of their nutritional behaviour. CONCLUSIONS/SIGNIFICANCE: Rodents have a high potential for the reconstruction of palaeoenvironmental conditions by means of bioapatite δ(18)O and δ(13)C analysis. No significant disadvantages compared to larger mammals were observed. However, for refined palaeoenvironmental reconstructions a better understanding of stable isotope signatures in modern analogous communities and potential biases due to seasonality effects, population dynamics and tissue formation rates is necessary.


Assuntos
Apatitas/química , Evolução Biológica , Osso e Ossos/anatomia & histologia , Roedores/anatomia & histologia , Dente/anatomia & histologia , Animais , Tamanho Corporal , Isótopos de Carbono/análise , Ecossistema , Fezes , Fósseis , Isótopos de Oxigênio/análise , Paleontologia/métodos , Filogenia , Dinâmica Populacional , Roedores/classificação , Estações do Ano , Estrigiformes/fisiologia
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