The Swedish Museum of Natural History (Swedish: Naturhistoriska riksmuseet, literally, the National Museum of Natural History), in Stockholm, is one of two major museums of natural history in Sweden, the other one being located in Gothenburg.The museum was founded in 1819 by the Royal Swedish Academy of Sciences, but goes back to the collections acquired mostly through donations by the academy since its foundation in 1739. These collections had first been made available to the public in 1786. The museum was separated from the Academy in 1965.One of the keepers of the collections of the academy during its earlier history was Anders Sparrman, a student of Carl Linnaeus and participant in the voyages of Captain James Cook. Another important name in the history of the museum is the zoologist, paleontologist and archaeologist Sven Nilsson, who brought the previously disorganised zoological collections of the museum into order during his time as keeper (1828–1831) before returning to Lund as professor.The present buildings for the museum in Frescati, Stockholm, was designed by the architect Axel Anderberg and completed in 1916, topped with a dome. As of 2014[update] it is the largest museum building in Sweden. The main campus of Stockholm University was later built next to the museum.The museum has Sweden's first purpose-built IMAX Dome cinema called Cosmonova, which opened in a dedicated annex of the museum in 1993. The cinema is also the largest planetarium in Sweden.The Index Herbariorum code assigned to this museum is S and it is used when citing housed specimens.
Assessments of arthropod herbivory patterns through deep time are reliant on accurate interpretations of feeding traces on fossil plants, which may be morphologically ambiguous. Prior work has emphasised the importance of ‘reaction rims’ for identifying herbivory, where the plant's histological response forms a region of altered and often thickened tissue that both seals and surrounds the damaged area during healing. However, the potential for diagenesis to form similar rimmed structures on plant fossils has not been well evaluated. In this study, we describe a collection of rimmed, subcircular structures on Glossopteris from the Wilton Formation (Upper Permian) of New South Wales, Australia. Although their morphology is consistent with recognised insect damage types (especially galling or hole feeding), less frequent, more poorly preserved examples that occur outside the leaf margins confirm a diagenetic origin. We hypothesise that these structures are the weathered remnants of small, concentric iron sulphide or siderite growths due to their rimmed morphology, association with iron oxide, and concentrated distribution on or near the fossilised Glossopteris. Our findings emphasise that diagenesis can create structures that superficially resemble insect feeding damage. Thus, although reaction rims remain a key criterion for identifying herbivory, care must also be taken to consider diagenetic and preservational factors so as not to artificially inflate the fossil record of insect herbivory.
Kimberlites allow exceptional insights deep into cratons by rapidly bringing to the surface well-preserved mantle fragments from a broad depth range. Water, mainly dissolved as hydroxyl, OH, is a key parameter for craton long-term stability as it affects viscosity and melting properties. We report here a multi-disciplinary (FTIR, Mössbauer, XANES, EPMA, LA-ICPMS) study of 17 harzburgite and dunite xenoliths from the Jagersfontein mine (Kaapvaal, South Africa) that are typical residues of high-degree melting (Mg# 92–94) and display minimum metasomatic interaction with the kimberlite as evidenced using trace elements. Thermobarometry yields 742–887 °C and 30-37.5 kbar for the equilibrium conditions of garnet free peridotites and 674–1084 °C and 27–51 kbar for garnet bearing peridotites. Oxygen fugacity, expressed as ΔlogfO2 relative to the FMQ buffer, varies between − 1.32 and − 0.29 ± 0.5 in the Cr-spinel bearing peridotites and between − 2.87 and − 0.57 ± 0.5 in garnet peridotites. OH content ([OH]) in the bulk rock varies between 29 and 99 ppm wt. H2O. Considering the low evidences of metasomatic interactions within the peridotites and the OH equilibrium between minerals, we suggest that the hydrogen content within the xenoliths remained pristine for billions of years. The [OH] decrease with depth can be explained by melting or, because bulk [OH] and ΔlogfO2 decrease with increasing depth, by a change in speciation from oxidized H2O to reduced H2 in line with thermodynamic modelling of fluid-saturated and undersaturated peridotite. Still, despite our efforts we did not observe H2 in the samples.
After 1970s, polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) concentrations peak in Baltic biota, concentrations started to decline following environmental legislation. However, in common guillemot eggs, this decline plateaued in 1990s, despite continued emissions reductions. Here, we test whether these contrasting trends can be explained by environmental and food web structural changes, including prey availability. Analysing temporal variation in the Central Baltic offshore fish community, including guillemot prey, we identified three structural phases: cod and herring dominance (1976–1986), sprat dominance (1987–2001), and stickleback population increase (2002–2021). We linked them with corresponding phases in PCDD/F trends: a steep decline (− 6.4
Little is known about the effects of invasive bryophytes on native biodiversity. To date, the main documented effect is competition, mostly with other bryophytes. Campylopus introflexus is an invasive moss in Europe and North America that can form dense monocultural carpets that displace native vegetation and influence the composition of native arthropod communities. It was first recorded in Sweden in 1976, where it commonly invades disturbed peatlands and its invasion potential is currently assessed as ‘severe’. Despite this long invasion history, little is understood about its local impacts, including on ground-dwelling arthropods. We analysed the effect of C. introflexus invasion on ground-dwelling beetle and spider communities at 14 sites in south-west Sweden. We collected arthropods along paired transects (50–200 m apart) in disturbed peatlands that were invaded or uninvaded by C. introflexus. Pitfall traps were emptied during the months of July, August, and September. We characterized the ground layer vegetation using quadrats (50 × 50 cm) centred over pitfall traps. We collected 2237 beetles belonging to 109 species from 18 families and 2139 spiders belonging to 85 species from 18 families. We found that C. introflexus invasion was associated with increased beetle abundance, richness, and diversity, but had no effect on spider abundance, richness, and diversity. We found no effect of C. introflexus invasion on beetle or spider community composition. Our results suggest that C. introflexus invasion into disturbed peatlands affects beetle communities, demonstrating that bryophyte invasions can have ecological consequences and highlighting the need for further research on this often overlooked group.
Reworking of limestone (CaCO3) by magma is an important source of carbon in volcanic arc emissions. However, while it is broadly understood that CO2 is liberated during magma-limestone interaction, the degassing behaviour of calcite in silicate melts is less well constrained. In this study, we carried out microspectroscopic analysis of volatiles within fluid inclusions and glass (former melt) in the products of short-term experiments simulating limestone assimilation in mafic arc melt (T = 1200 degrees C, P = 0.5 GPa, runtimes of 0 to 300 s). The experimental products consist of partly to wholly assimilated limestone xenoliths enveloped by CaO-rich silicate glass (reacting melt) that grades into mafic glass (host melt). Micro-to milli-metric sized fluid-filled bubbles permeate the experimental products. This study reveals that limestone assimilation induces extremely fast apparent diffusivity of CO2 (DCO2 greater than or similar to 10-7 m2/s) through both the reacting melt and the host melt. Volatile saturation is thus quickly reached, triggering nucleation of bubbles mainly containing CO2 +/- CO, CH4, N2, H2, and H2O. Crucially, we find that the host melt contains dissolved CO2 from limestone, despite showing no other compositional evidence for limestone assimilation. Mafic melts in volcanic regions underlain by limestone may therefore mobilise and transport more carbon than previously thought, with implications for eruptive behaviour, volcanic CO2 inventories, and long-term climate warming.
