14 results on '"Tietje M"'
Search Results
2. Evolutionary and ecophenotypic controls on bivalve body size distributions following the end-Permian mass extinction
- Author
-
Foster, W.J., primary, Gliwa, J., additional, Lembke, C., additional, Pugh, A.C, additional, Hofmann, R., additional, Tietje, M., additional, Varela, S., additional, Foster, L.C., additional, Korn, D., additional, and Aberhan, M., additional
- Published
- 2020
- Full Text
- View/download PDF
3. Chemostratigraphy Across the Permian‐Triassic Boundary
- Author
-
Schobben, M, Heuer, F., Tietje, M., Ghaderi, A, Korn, D, Korte, Christoph, Wignall, Paul B., Sial, A. N., Gaucher, C., Ramkumar, M., Ferreira, V. P., Marine Palynology, and Marine palynology and palaeoceanography
- Subjects
isotope stratigraphic markers ,Permian ,Lithology ,microbially‐mediated precipitates ,carbonate polymorphs ,Paleontology ,chemistry.chemical_compound ,chemistry ,Isotopes of carbon ,Chemostratigraphy ,Dissolved organic carbon ,Facies ,carbonate microfacies ,carbonate diagenesis ,Carbonate rock ,Carbonate ,carbonate archive ,Geology - Abstract
A major extinction pulse occurred just below the conodont‐defined Permian‐Triassic boundary. Global‐scale compilations of increasingly larger paleontological, sedimentological, and geochemical datasets further amplify our understanding of this event by unraveling temporospatial patterns. Robust stratigraphic frameworks are an integral part of these worldwide compilations. Bulk carbonate rock carbon isotope records are a widely used, and easy‐to‐generate, stratigraphic tool; it can substitute for biostratigraphy. However, inconsistencies in the amplitude and shape of stratigraphic carbon isotope patterns have also hampered the successful linkages of different geographic locations. In this study, we focus on the multicomponent nature of various limestone facies. We show how sampling strategies can be adapted in order to retrieve material from this multicomponent system that will most likely represent secular patterns in marine dissolved inorganic carbon δ13C. By obtaining multiple and randomly chosen bed‐internal samples, we reveal that the magnitude of bed‐internal δ13C variations can differ between distinct lithologies. However, we also note that the largest within‐bed variations (in excess of 0.5‰) do not correspond to obvious textural variations for this specific rock. Bed‐internal variations do not always trace marine dissolved inorganic carbon δ13C and might cause identification of ambiguous isotope stratigraphic markers that do not allude to globally correlative signals.
- Published
- 2018
4. Chemostratigraphy across the Permian-Triassic Boundary: The Effect of Sampling Strategies on Carbonate-carbon Isotope Stratigraphic Markers
- Author
-
Schobben, M, Heuer, F., Tietje, M., Ghaderi , A, Korn , D, Korte, Christoph, Wignall, Paul B., Sial, A. N., Gaucher, C., Ramkumar, M., Ferreira, V. P., Marine Palynology, and Marine palynology and palaeoceanography
- Subjects
carbonate polymorphs ,isotope stratigraphic markers ,carbonate microfacies ,carbonate diagenesis ,carbonate archive ,microbially‐mediated precipitates - Abstract
A major extinction pulse occurred just below the conodont‐defined Permian‐Triassic boundary. Global‐scale compilations of increasingly larger paleontological, sedimentological, and geochemical datasets further amplify our understanding of this event by unraveling temporospatial patterns. Robust stratigraphic frameworks are an integral part of these worldwide compilations. Bulk carbonate rock carbon isotope records are a widely used, and easy‐to‐generate, stratigraphic tool; it can substitute for biostratigraphy. However, inconsistencies in the amplitude and shape of stratigraphic carbon isotope patterns have also hampered the successful linkages of different geographic locations. In this study, we focus on the multicomponent nature of various limestone facies. We show how sampling strategies can be adapted in order to retrieve material from this multicomponent system that will most likely represent secular patterns in marine dissolved inorganic carbon δ13C. By obtaining multiple and randomly chosen bed‐internal samples, we reveal that the magnitude of bed‐internal δ13C variations can differ between distinct lithologies. However, we also note that the largest within‐bed variations (in excess of 0.5‰) do not correspond to obvious textural variations for this specific rock. Bed‐internal variations do not always trace marine dissolved inorganic carbon δ13C and might cause identification of ambiguous isotope stratigraphic markers that do not allude to globally correlative signals.
- Published
- 2018
5. Tunneling in photochemical solid-state H-transfer.
- Author
-
Tietje, M., primary, Von Borczyskowski, C., additional, Prass, B., additional, and Stehlik, D., additional
- Published
- 1986
- Full Text
- View/download PDF
6. Meta-analysis shows that wild large herbivores shape ecosystem properties and promote spatial heterogeneity.
- Author
-
Trepel J, le Roux E, Abraham AJ, Buitenwerf R, Kamp J, Kristensen JA, Tietje M, Lundgren EJ, and Svenning JC
- Subjects
- Animals, Biodiversity, Soil, Biological Evolution, Ecosystem, Herbivory
- Abstract
Megafauna (animals ≥45 kg) have probably shaped the Earth's terrestrial ecosystems for millions of years with pronounced impacts on biogeochemistry, vegetation, ecological communities and evolutionary processes. However, a quantitative global synthesis on the generality of megafauna effects on ecosystems is lacking. Here we conducted a meta-analysis of 297 studies and 5,990 individual observations across six continents to determine how wild herbivorous megafauna influence ecosystem structure, ecological processes and spatial heterogeneity, and whether these impacts depend on body size and environmental factors. Despite large variability in megafauna effects, we show that megafauna significantly alter soil nutrient availability, promote open vegetation structure and reduce the abundance of smaller animals. Other responses (14 out of 26), including, for example, soil carbon, were not significantly affected. Further, megafauna significantly increase ecosystem heterogeneity by affecting spatial heterogeneity in vegetation structure and the abundance and diversity of smaller animals. Given that spatial heterogeneity is considered an important driver of biodiversity across taxonomic groups and scales, these results support the hypothesis that megafauna may promote biodiversity at large scales. Megafauna declined precipitously in diversity and abundance since the late Pleistocene, and our results indicate that their restoration would substantially influence Earth's terrestrial ecosystems., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)
- Published
- 2024
- Full Text
- View/download PDF
7. Functional traits-not nativeness-shape the effects of large mammalian herbivores on plant communities.
- Author
-
Lundgren EJ, Bergman J, Trepel J, le Roux E, Monsarrat S, Kristensen JA, Pedersen RØ, Pereyra P, Tietje M, and Svenning JC
- Subjects
- Animals, Ecology, Phylogeny, Conservation of Natural Resources, Ecosystem, Herbivory physiology, Mammals, Plants, Extinction, Biological, Introduced Species
- Abstract
Large mammalian herbivores (megafauna) have experienced extinctions and declines since prehistory. Introduced megafauna have partly counteracted these losses yet are thought to have unusually negative effects on plants compared with native megafauna. Using a meta-analysis of 3995 plot-scale plant abundance and diversity responses from 221 studies, we found no evidence that megafauna impacts were shaped by nativeness, "invasiveness," "feralness," coevolutionary history, or functional and phylogenetic novelty. Nor was there evidence that introduced megafauna facilitate introduced plants more than native megafauna. Instead, we found strong evidence that functional traits shaped megafauna impacts, with larger-bodied and bulk-feeding megafauna promoting plant diversity. Our work suggests that trait-based ecology provides better insight into interactions between megafauna and plants than do concepts of nativeness.
- Published
- 2024
- Full Text
- View/download PDF
8. Global hotspots of plant phylogenetic diversity.
- Author
-
Tietje M, Antonelli A, Forest F, Govaerts R, Smith SA, Sun M, Baker WJ, and Eiserhardt WL
- Subjects
- Humans, Phylogeny, Plants, Ecosystem, Biodiversity, Conservation of Natural Resources methods
- Abstract
Regions harbouring high unique phylogenetic diversity (PD) are priority targets for conservation. Here, we analyse the global distribution of plant PD, which remains poorly understood despite plants being the foundation of most terrestrial habitats and key to human livelihoods. Capitalising on a recently completed, comprehensive global checklist of vascular plants, we identify hotspots of unique plant PD and test three hypotheses: (1) PD is more evenly distributed than species diversity; (2) areas of highest PD (often called 'hotspots') do not maximise cumulative PD; and (3) many biomes are needed to maximise cumulative PD. Our results support all three hypotheses: more than twice as many regions are required to cover 50% of global plant PD compared to 50% of species; regions that maximise cumulative PD substantially differ from the regions with outstanding individual PD; and while (sub-)tropical moist forest regions dominate across PD hotspots, other forest types and open biomes are also essential. Safeguarding PD in the Anthropocene (including the protection of some comparatively species-poor areas) is a global, increasingly recognised responsibility. Having highlighted countries with outstanding unique plant PD, further analyses are now required to fully understand the global distribution of plant PD and associated conservation imperatives across spatial scales., (© 2023 The Authors. New Phytologist © 2023 New Phytologist Foundation.)
- Published
- 2023
- Full Text
- View/download PDF
9. A global assessment of the Raunkiaeran shortfall in plants: geographic biases in our knowledge of plant traits.
- Author
-
Maitner B, Gallagher R, Svenning JC, Tietje M, Wenk EH, and Eiserhardt WL
- Subjects
- Phenotype, Bias, Plants, Ecosystem
- Published
- 2023
- Full Text
- View/download PDF
10. Global variation in diversification rate and species richness are unlinked in plants.
- Author
-
Tietje M, Antonelli A, Baker WJ, Govaerts R, Smith SA, and Eiserhardt WL
- Subjects
- Biodiversity, Climate, Datasets as Topic, Ecosystem, Phylogeny, Extinction, Biological, Genetic Speciation, Plants classification, Plants genetics
- Abstract
Species richness varies immensely around the world. Variation in the rate of diversification (speciation minus extinction) is often hypothesized to explain this pattern, while alternative explanations invoke time or ecological carrying capacities as drivers. Focusing on seed plants, the world's most important engineers of terrestrial ecosystems, we investigated the role of diversification rate as a link between the environment and global species richness patterns. Applying structural equation modeling to a comprehensive distribution dataset and phylogenetic tree covering all circa 332,000 seed plant species and 99.9% of the world's terrestrial surface (excluding Antarctica), we test five broad hypotheses postulating that diversification serves as a mechanistic link between species richness and climate, climatic stability, seasonality, environmental heterogeneity, or the distribution of biomes. Our results show that the global patterns of species richness and diversification rate are entirely independent. Diversification rates were not highest in warm and wet climates, running counter to the Metabolic Theory of Ecology, one of the dominant explanations for global gradients in species richness. Instead, diversification rates were highest in edaphically diverse, dry areas that have experienced climate change during the Neogene. Meanwhile, we confirmed climate and environmental heterogeneity as the main drivers of species richness, but these effects did not involve diversification rates as a mechanistic link, calling for alternative explanations. We conclude that high species richness is likely driven by the antiquity of wet tropical areas (supporting the "tropical conservatism hypothesis") or the high ecological carrying capacity of warm, wet, and/or environmentally heterogeneous environments.
- Published
- 2022
- Full Text
- View/download PDF
11. USP42 protects ZNRF3/RNF43 from R-spondin-dependent clearance and inhibits Wnt signalling.
- Author
-
Giebel N, de Jaime-Soguero A, García Del Arco A, Landry JJM, Tietje M, Villacorta L, Benes V, Fernández-Sáiz V, and Acebrón SP
- Subjects
- Animals, Mice, Receptors, G-Protein-Coupled genetics, Ubiquitination, Wnt Signaling Pathway, Thrombospondins genetics, Thrombospondins metabolism, Ubiquitin-Protein Ligases metabolism
- Abstract
The tumour suppressors RNF43 and ZNRF3 play a central role in development and tissue homeostasis by promoting the turnover of the Wnt receptors LRP6 and Frizzled (FZD). The stem cell growth factor R-spondin induces auto-ubiquitination and membrane clearance of ZNRF3/RNF43 to promote Wnt signalling. However, the deubiquitinase stabilising ZNRF3/RNF43 at the plasma membrane remains unknown. Here, we show that the USP42 antagonises R-spondin by protecting ZNRF3/RNF43 from ubiquitin-dependent clearance. USP42 binds to the Dishevelled interacting region (DIR) of ZNRF3 and stalls the R-spondin-LGR4-ZNRF3 ternary complex by deubiquitinating ZNRF3. Accordingly, USP42 increases the turnover of LRP6 and Frizzled (FZD) receptors and inhibits Wnt signalling. Furthermore, we show that USP42 functions as a roadblock for paracrine Wnt signalling in colon cancer cells and mouse small intestinal organoids. We provide new mechanistic insights into the regulation R-spondin and conclude that USP42 is crucial for ZNRF3/RNF43 stabilisation at the cell surface., (© 2021 The Authors. Published under the terms of the CC BY NC ND 4.0 license.)
- Published
- 2021
- Full Text
- View/download PDF
12. Diversity partitioning in Phanerozoic benthic marine communities.
- Author
-
Hofmann R, Tietje M, and Aberhan M
- Subjects
- Animals, History, Ancient, Oceans and Seas, Paleontology, Aquatic Organisms, Biodiversity, Fossils
- Abstract
Biotic interactions such as competition, predation, and niche construction are fundamental drivers of biodiversity at the local scale, yet their long-term effect during earth history remains controversial. To test their role and explore potential limits to biodiversity, we determine within-habitat (alpha), between-habitat (beta), and overall (gamma) diversity of benthic marine invertebrates for Phanerozoic geological formations. We show that an increase in gamma diversity is consistently generated by an increase in alpha diversity throughout the Phanerozoic. Beta diversity drives gamma diversity only at early stages of diversification but remains stationary once a certain gamma level is reached. This mode is prevalent during early- to mid-Paleozoic periods, whereas coupling of beta and gamma diversity becomes increasingly weak toward the recent. Generally, increases in overall biodiversity were accomplished by adding more species to local habitats, and apparently this process never reached saturation during the Phanerozoic. Our results provide general support for an ecological model in which diversification occurs in successive phases of progressing levels of biotic interactions., Competing Interests: Conflict of interest statement: Michael Hautmann (University of Zurich), the author of the diversification model which is herein used to link diversity trajectories to competition, has been the thesis advisor of the first author., (Copyright © 2019 the Author(s). Published by PNAS.)
- Published
- 2019
- Full Text
- View/download PDF
13. Evaluating the predicted extinction risk of living amphibian species with the fossil record.
- Author
-
Tietje M and Rödel MO
- Subjects
- Animals, Conservation of Natural Resources, Amphibians, Extinction, Biological, Fossils
- Abstract
Bridging the gap between the fossil record and conservation biology has recently become of great interest. The enormous number of documented extinctions across different taxa can provide insights into the extinction risk of living species. However, few studies have explored this connection. We used generalised boosted modelling to analyse the impact of several traits that are assumed to influence extinction risk on the stratigraphic duration of amphibian species in the fossil record. We used this fossil-calibrated model to predict the extinction risk for living species. We observed a high consensus between our predicted species durations and the current IUCN Red List status of living amphibian species. We also found that today's Data Deficient species are mainly predicted to experience short durations, hinting at their likely high threat status. Our study suggests that the fossil record can be a suitable tool for the evaluation of current taxa-specific Red Listing status., (© 2018 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.)
- Published
- 2018
- Full Text
- View/download PDF
14. Contradicting habitat type-extinction risk relationships between living and fossil amphibians.
- Author
-
Tietje M and Rödel MO
- Abstract
Trait analysis has become a crucial tool for assessing the extinction risk of species. While some extinction risk-trait relationships have been often identical between different living taxa, a temporal comparison of fossil taxa with related current taxa was rarely considered. However, we argue that it is important to know if extinction risk-trait relations are constant or changing over time. Herein we investigated the influence of habitat type on the persistence length of amphibian species. Living amphibians are regarded as the most threatened group of terrestrial vertebrates and thus of high interest to conservationists. Species from different habitat types show differences in extinction risk, i.e. species depending on flowing waters being more threatened than those breeding in stagnant sites. After assessing the quality of the available amphibian fossil data, we show that today's habitat type-extinction risk relationship is reversed compared to fossil amphibians, former taxa persisting longer when living in rivers and streams, thus suggesting a change of effect direction of this trait. Neither differences between amphibian orders nor environmentally caused preservation effects could explain this pattern. We argue this change to be most likely a result of anthropogenic influence, which turned a once favourable strategy into a disadvantage., Competing Interests: We declare we have no competing interests.
- Published
- 2017
- Full Text
- View/download PDF
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.