Recycling of Earth's crust through subduction and delamination contributes to mantle heterogeneity. Melt inclusions in early crystallised magmatic minerals record greater geochemical variability than host lavas and more fully reflect the heterogeneity of magma sources. To date, use of multiple isotope systems on small (< 300 μm) melt inclusions was hampered by analytical limitations. Here we report the first coupled Sr-Nd-Pb isotope data on individual melt inclusions from potassium-rich lavas from neighbouring Quaternary volcanoes in central Italy and infer the presence of a previously unidentified ancient lower crustal component in the mantle. We suggest derivation from Variscan or older basement included in the upper mantle by either delamination, sediment recycling, subduction erosion and/or slab detachment processes during Cenozoic subduction and collision of the western Mediterranean. The capability to determine isotope ratios in individual melt inclusions permits the detection of distinctive mantle contaminants and can provide insights into how geodynamic processes affect subduction recycling.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6642164 | PMC |
http://dx.doi.org/10.1038/s41467-019-11072-5 | DOI Listing |
Curr Biol
December 2024
Department of Biochemistry, University of Cambridge, Tennis Court Road, Cambridge CB2 1QW, UK. Electronic address:
The plastids of photosynthetic organisms on land are predominantly "primary plastids," derived from an ancient endosymbiosis of a cyanobacterium. Conversely, the plastids of marine photosynthetic organisms were mostly gained through subsequent endosymbioses of photosynthetic eukaryotes generating so-called "complex plastids." The plastids of the major eukaryotic lineages-cryptophytes, haptophytes, ochrophytes, dinoflagellates, and apicomplexans-were posited to derive from a single secondary endosymbiosis of a red alga in the "chromalveloate" hypothesis.
View Article and Find Full Text PDFArchaeol Anthropol Sci
November 2024
Ecole Normale Supérieure de Lyon and CNRS, Lyon, France.
Unlabelled: Local types of coinage testify to the emerging use of silver in the Balkan interior, possibly related to abundant ore deposits in the region. Here, we present Pb isotope data for silver coins minted by local tribes and settlements (anepigraphic coins attributed to the Derrones/Laeaei, Damastion, Pelagia, Kings of Paeonia) between the 5th and 3rd centuries BCE. For comparison, we analysed coinage of the potential Greek Dyrrhachium and Apollonia for their main element and Pb-Ag isotope compositions.
View Article and Find Full Text PDFPLoS One
July 2024
Institute of Archaeology, The Hebrew University of Jerusalem, Jerusalem, Israel.
A longstanding debate concerns the function of carinated elements in both, the Levantine, and European Aurignacian. The present study aims to contribute to this topic with the evaluation of the carinated assemblage from layer D in Hayonim Cave, Western Galilee, Israel, one of the type sites of the Levantine Aurignacian. An operational chain reconstruction with an attribute analysis is paired with a typological approach to the preparation and maintenance products based on artefacts defined as West European Aurignacian.
View Article and Find Full Text PDFISME J
January 2024
Department of Insect Symbiosis, Max Planck Institute for Chemical Ecology, 07745 Jena, Germany.
Many insects feeding on nutritionally challenging diets like plant sap, leaves, or wood engage in ancient associations with bacterial symbionts that supplement limiting nutrients or produce digestive or detoxifying enzymes. However, the distribution, function, and evolutionary dynamics of microbial symbionts in insects exploiting other plant tissues or relying on a predacious diet remain poorly understood. Here, we investigated the evolutionary history and function of the intracellular gamma-proteobacterial symbiont "Candidatus Dasytiphilus stammeri" in soft-winged flower beetles (Coleoptera, Melyridae, Dasytinae) that transition from saprophagy or carnivory to palynivory (pollen-feeding) between larval and adult stage.
View Article and Find Full Text PDFPsychol Sci
July 2024
Department of Cognitive and Information Sciences, University of California-Merced.
According to accounts of neural reuse and embodied cognition, higher-level cognitive abilities recycle evolutionarily ancient mechanisms for perception and action. Here, building on these accounts, we investigate whether creativity builds on our capacity to forage in space ("creativity as strategic foraging"). We report systematic connections between specific forms of creative thinking-divergent and convergent-and corresponding strategies for searching in space.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!