The abundance and distribution of rare-earth elements (REE) within fish debris from the Japanese Exclusive Economic Zone around Minami-Torishima Island have been investigated to determine the host materials of REE in the REE-rich deep-sea mud. The study was performed using REE-extraction experiments, field emission electron probe microanalysis (FE-EPMA), transmission electron microscopy with an energy-dispersive X-ray spectrometer (TEM-EDX), laser-induced breakdown spectroscopy (LIBS), Fourier-transform infrared (FTIR) spectroscopy and X-ray absorption near edge structure (XANES) analysis.

The EPMA data indicate that the amount of REE in the apatite in the teeth is less than that in the bone debris. According to TEM-EDX analysis, yttrium (Y) is contained in the rod-like apatite crystals in the bone debris, but not in the long rod-like apatite crystals of the teeth. Analyses by LIBS and EPMA indicate that Y-rich bone debris is also rich in C. The FTIR spectroscopic analysis indicates the presence of carbonate groups within the Y-rich apatite structure. Moreover, the results of the XANES analysis and REE-extraction experiments indicate that Y occurs within the crystal structure of C-bearing apatite in the bone debris. These results suggest that the REE within C-bearing apatite in the fish debris from the Minami-Torishima REE-rich deep-sea mud substitute for Ca in apatite via an ionic exchange reaction, probably Ca2⁺ + P⁵⁺ ↔ REE3⁺ + C⁴⁺.

Minerals incorporate 72 different essential elements, many of which are redox sensitive. We compiled oxidation states of ions in 4834 IMA-approved mineral species with oxygen and/or halogens as anions and have identified 87 essential mineral-forming ions. We compiled data on the coexistence of these ions as recorded in their minerals’ chemical formulas, and applied methods of network analysis with community detection and heatmap analysis with agglomerative clustering to reveal patterns of ion coexistence.

Unipartite networks illustrate the most common coexisting ion pairs, whereas Louvain and Walktrap methods reveal distinct ion groups—patterns that both reinforce and refine the Goldschmidt geochemical classification of elements. Key findings include: (1) that mineral-forming ions group into two major communities with a number of subcommunities; (2) that different ion communities primarily reflect contrasting geochemical and paragenetic processes such as primary igneous mineralisation, hydrothermal precipitation, and near-surface oxidation and weathering, rather than crystal chemical constraints; and (3) that different oxidation states of some redox-sensitive elements fall into two or more of these communities, underscoring how ions of the same elements commonly display contrasting geochemical and/or paragenetic affinities.

Heatmap analysis reveals groupings of co-occurring ions that mimic many aspects of community detection methods, as well as significant patterns of ion antipathies—groups of ions that are seldom if ever paired. For example, alkali metals commonly associated with late-stage igneous fluids (Cs+, Li+ and Rb+) rarely co-occur with low field strength ions found concentrated in brines (Ag+, Br–, Cu+, Hg+ and I–) or high field strength ions from weathered primary oxide or sulfide deposits (Cr6+, Pb4+, Mo4+, Te4+ and Te6+). Such ion pairs are well known in synthetic oxides. Therefore, with the exceptions of cations having very different redox potentials, unobserved ion pairs are principally the consequences of element rarity coupled with natural geochemical and paragenetic antipathies rather than crystal chemical constraints.

Woodrats of the genus Neotoma are an important study system for ecological and paleoecological research. However, paleontological studies are often hindered by the difficulty of identifying woodrat remains to species. We address this limitation by using 2D landmark-based geometric morphometrics to classify 199 lower first molars (m1s) of five extant western North American Neotoma species (N. albigula, N. cinerea, N. fuscipes, N. lepida, and N. macrotis) collected throughout California. We then use discriminant analysis of principal components (DAPC) models to identify Late Pleistocene fossils of unknown species from the Rancho La Brea Tar Pits in Los Angeles, California. DAPC correctly identifies ∼85–90% of extant individuals to species, with most misclassifications occurring between sister taxa N. fuscipes and N. macrotis. Most fossil m1s are classified as N. macrotis by DAPC, which may be the first confirmation of N. macrotis in the fossil record. We show that landmark-based geometric morphometric analyses are generally effective at differentiating m1s of extant Neotoma species in California and they are an auspicious method for unknown fossil identification. Further applications of this method across a broader range of geographic locations and species will better contextualize its utility.

Bornite (Cu5FeS4) and digenite (Cu9–xFexS5; x = 0.4) have closely related cubic structures and are known for their range of superstructures derived from metal vacancies leading to larger unit cells expressed as n × a, where a = ∼5.5 Å and n is an integer. Such polymorphs can form during cooling from higher temperature bornite (Bn)–digenite (Dg) 1a solid solution (ss). The alleged basket-weave textures in natural bornite are investigated using high-angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) imaging and energy-dispersive X-ray spectrometry. These techniques, combined with crystal modelling and STEM simulations, are suitable for depicting changes in phases related to crystal-structural modularity as they collectively better reproduce atomic distributions in real space. Bornite associated with either chalcocite or chalcopyrite from the Olympic Dam Cu-U-Au-Ag deposit, South Australia has non-stoichiometric Cu/Fe ratios and displays nanoscale basket-weave textures between the main components Bn2a and anilite (Cu7S4); Dg1a is preserved throughout, albeit as a minor phase. Anilite is a derivative of digenite, whereby a = b = √2aDg and c = 2aDg. Two intermediate phases, Dg3a and Bn2a4a, are documented and an additional phase, Bn2a6a, is tentatively suggested to occur in Fe-rich nanodomains within Bn2a. Considering the epitaxial relationships between all phases, we infer that basket-weave textures record phase transitions via polymorphic transformations of parent Bn2a and Dg1a during cooling. Observed phase assemblages are thus linked to cooling of Bn–Dgss in the range 70–87 mol.% Bn along a Cu6.18Fe1.26S5 – Cu9.12Fe0.89S5 tie-line defined from measured compositions. We depict three associations: Bn2a + Dg1a, Bn2a4a + Dg3a, and Bn2a4a/Bn2a6a + anilite, formed during cooling. Polymorph associations like these are relevant for enrichment of critical/precious metals in copper ores because Bi, Pb, Ag, Te and, probably also Au, if dissolved in Bn–Dgss, could be incorporated into superstructures during Cu-Fe-sulfide phase transitions.

Based on present knowledge of atmospheric composition, a mechanism for the natural formation of vesicles in the lakes of Titan is proposed. It involves precipitation-induced spray droplets coated by a monolayer of amphiphiles. On interaction with the monolayer on the lake’s surface, bilayer membranes are being formed that encapsulate the liquid phase of the original droplet. The resulting vesicles develop thermodynamic stability by continuous compositional selection of various types of amphiphiles in a dynamic equilibrium, leading to an optimized vesicle stability. Different populations of stable vesicles may compete, initiating a long-term evolution process that could eventually result in primitive protocells. The existence of any type of vesicles on Titan would prove that early steps towards increasing order and complexity have taken place, which represent the necessary precondition for abiogenesis. A valid analytical approach could involve a laser device with combined light scattering analysis and surface enhanced Raman spectroscopy. It would allow for very sensitive detection of amphiphiles as well as for the observation of dispersed vesicles.

Rodney M. Feldmann (1939–2024) had a remarkable scientific career. Publishing primarily in paleontology and geology during seven decades, his legacy includes more than 500 journal articles, conference proceedings, books, book chapters, field guides, and laboratory manuals, in addition to many abstracts of talks presented at conferences. His published work has considerable breadth, but much of it concerns the paleobiology of decapods and other crustaceans. He supervised 47 M.S. theses and 14 Ph.D. dissertations and served in multiple societies and organizations and on editorial boards. Prof. Feldmann was an inspiration to his many students and colleagues around the globe and has left a lasting impact on science.

Here we present the resistance of two halophilic Archaea, Halorubrum (Hrr.) sp. AS12 and Haloarcula (Har.). sp. NS06, isolated from the brine in Lunenburg, Germany, to stress factors including desiccation, radiation and elevated perchlorate concentration. This is the first study to describe the stress resistance of halophilic Archaea isolated from the Lunenburg brine. While Hrr. sp. AS12 tolerates desiccation up to 45 days with a -log3 reduction in survival, Har. sp. NS06 displays a strong decline in viability and no detectable survival following 21 days. In contrast, Hrr. sp. AS12 was more sensitive towards X-Ray irradiation with a significant decline in viability (D10 228,2 ± 8,9 Gy) while Har. sp. NS06 showed a slight decline in survival following exposure to 1 kGy. The resistance of both strains against germicidal UV-C254nm radiation follows a similar pattern when compared to X-ray exposure with Hrr. sp. AS12 displaying more sensitivity to UV-C radiation (F10 111,6 ± 6,4 J/m2) compared to Har. sp. NS06 (F10 194,9 ± 13,7 J/m2). Exposure to He, Ar, and Fe heavy ions up to 500 Gy showed little effect on the survivability; however, the transport control of Hrr. sp. AS12 showed a strong decline (-log3 reduction) in survival. Both strains revealed increased growth in the presence of perchlorates (NaClO4 and MgClO4) with a clear preference to NaClO4 up to 5%. Our results provide a first insight into the stress resistance of these two isolates and will further develop our understanding of the parameters of life on Earth and potentially on other planets.

While it is vital to agree to a set of global objectives and targets to reduce plastic pollution as part of the Global Plastic Treaty, past negotiations have been troubled by differences in regional and national priorities and needs. To take these different priorities and needs into account, this letter proposes the adoption of an interdisciplinary source-to-sea approach. A source-to-sea approach emphasizes the connected nature between land-based sources of marine plastic pollution along the life cycle of plastic products on the one hand, and air, soil, and water cycles that determine marine plastic flows and associated sustainability risks on the other hand. It takes into account how we know more about the way in which production, use and plastic waste contribute to the pollution of rivers and seas in one location (e.g. in Europe), than we do for rivers and seas in other places (e.g. Africa). There are also regional and national differences in how much awareness exist about plastic pollution and how it is governed and regulated. These differences translate in different priorities and needs in terms of how to most efficiently and effectively reduce plastic pollution. The letter argues that these differences should be embraced and that an interdisciplinary source-to-sea approach can help to develop tailor-made regional and national targets and measures that in turn contribute to achieving the global ambitions of the Global Plastic Treaty. A key role is foreseen for existing governance institutions, such as river basin commissions and regional seas conventions (coordinated by UNEP Regional seas Programme), while the Global Plastic Treaty can become a platform for sharing of approaches, lessons and strategies between regions and countries so that over time, plastic pollution will be reduced worldwide.

In Iceland, sheltered rocky intertidal zones like Breiðafjörður bay are dominated by monospecific stands of Ascophyllum nodosum, providing key habitats for marine organisms. Increasing demand for A. nodosum has led to its commercial exploitation, yet impacts on fish assemblages remain poorly known. Using a novel multi-mesh netting approach, we characterised seasonal patterns in fish composition, abundance, size structure, age, and diet. Additionally, to assess the local effects of seaweed harvesting, commercial harvesting was conducted, with comparisons being made between treatment and control unharvested areas during different seasons. Nine fish species were identified, with Pollachius virens, Myoxocephalus scorpius, and Gadus morhua being the most common. Fish abundance peaked in summer, and declined the following spring, suggesting cohort turnover with juvenile gadoids relying on these habitats as nurseries. P. virens showed increased length through seasons, whereas no trends in length or abundance were observed for M. scorpius. Effects of seaweed harvesting were minimal, although fish diversity was slightly higher and G. morhua significantly larger in control plots. Stomach contents exhibited a greater diversity of prey types in harvested sites, suggesting potential impacts on trophic dynamics. These findings underscore the importance of A. nodosum-dominated habitats as nursery grounds for commercially valuable gadoids and highlight the need for a precautionary approach to seaweed harvesting to maintain ecosystem health.

The Mazon Creek Lagerstätte (Moscovian Stage, late Carboniferous Period; Illinois, USA) captures a diverse view of ecosystems in delta-influenced coastal settings through exceptional preservation of soft tissues in siderite concretions. The generally accepted paradigm of the Mazon Creek biota has been that of an inferred paleoenvironmental divide between what have been termed the Braidwood and Essex assemblages, wherein the former represents a freshwater ecosystem with terrestrial input and the latter a marine-influenced prodelta setting with abundant cnidarians, bivalves, worm phyla, and diverse arthropods. Here, we revisit the paleoecology of the Mazon Creek biota by analyzing data from nearly 300,000 concretions from more than 270 locations with complementary multivariate ordinations. Our results show the Braidwood assemblage as a legitimate shoreward community and provide evidence for further subdivision of the Essex assemblage into two distinct subassemblages, termed here the Will-Essex and Kankakee-Essex. The Will-Essex represents a benthos dominated by clams and trace fossils along the transition between nearshore and offshore deposits. The Kankakee-Essex is dominated by cnidarians, presenting an ecosystem approaching the geographic margin of this taphonomic window. These new insights also allow a refined taphonomic model, wherein recalcitrant tissues of Braidwood organisms were subject to rapid burial rates, while organisms of the Essex assemblage typically had more labile tissues and were subject to slower burial rates. Consequently, we hypothesize that the Braidwood fossils should record more complete preservation than the Essex, which was exposed for longer periods of aerobic decomposition. This is supported by a higher proportion of non-fossiliferous concretions in the Essex than in the Braidwood.

Peloids are natural therapeutic muds or clays used in balneotherapy and other health treatments. The aim of this study is to prepare and qualify three artificial peloids by maturation for 360 days of some Tunisian smectitic clays with a naturally chlorinated sodic mineral water from a spring in Korbous, Tunisia. This was done to improve our understanding of the behaviour of these clays and the physicochemical changes that affect the clays during maturation, with the purpose of providing suitable raw materials as a solid phase for peloid preparation. The results showed that parameters such as mineralogy, geochemistry, granulometry, cation-exchange capacity, consistency parameters (Atterberg limits and plasticity index), specific surface area, cooling kinetics and pH are all affected by the geochemistry of the thermal water used during maturation. Mineralogical modifications mostly concern the clay minerals’ contents, particularly smectite, and subordinately the dissolution of gypsum and the neoformation of halite. The observed improvements to the plasticity index and cooling kinetics can be explained by the ability of water molecules, and especially cations, to diffuse into the clay particles. The main exchangeable cations are Na+ and Ca2+, along with Mg2+ and K+, which promote swelling and increase water retention and consequently retention of heat in thermal spa treatments. The chemical composition of the major elements is closely linked to the mineralogical compositions of the clays, and also to the chemical composition of the thermal water used in their maturation. The safety profiles of the peloids obtained at different maturation times were evaluated, particularly regarding their content of potentially toxic elements such as arsenic.

Predicting calving in glacier models is challenging, as observations of diverse calving styles appear to contradict a universal calving law. Here, we generalize and apply the analytical Horizontal Force-Balance fracture model from ice shelves to land- and marine-terminating glaciers. We consider different combinations of “crack configurations” including surface crevasses with or without meltwater above saltwater- or meltwater-filled basal crevasses. Our generalized crevasse-depth model analytically reveals that, in the absence of meltwater, the calving criterion depends on two dimensionless variables: buttressing B and dimensionless water level λ. Using a calving regime diagram, we quantitatively demonstrate that glaciers are generally more prone to calving with reduced buttressing B and lower water level λ. For a specified set of $B, \lambda$ and crack configuration, an analytical calving law can be derived. For example, the calving law for an ice shelf, land-, or marine-terminating glacier with a dry surface crevasse above a saltwater basal crevasse reduces to a state with no buttressing (B = 0). With climate warming, glaciers are expected to become more vulnerable to calving due to meltwater-driven surface and basal crevassing. Our findings provide a framework for understanding diverse calving styles.

The Intergovernmental Negotiating Committee (INC) on plastic pollution are United Nations member states who will convene for the second part of the fifth session of the Intergovernmental Negotiating Committee in Geneva (INC5.2) 5-14 August, 2025 to negotiate a global plastics treaty. The Scientists’ Coalition for an Effective Plastics Treaty (‘The Scientists’ Coalition’) is an international network of independent scientific and technical experts who have been contributing robust science to treaty negotiators since INC1 in 2022. The Scientists’ Coalition established a series of working groups following INC5.1 in Busan, Korea 25 November – 1 December 2024. Each working group has produced science-based responses to the selected articles of ‘the Chair’s text’ (the latest version of the draft global plastics treaty text). This Letter to the Editor summarises those responses.

Coral reefs have been rapidly deteriorating, worldwide, due to global warming, ocean acidification, bleaching, diseases, and various local anthropogenic stressors, such as coastal development, habitat destruction, overfishing and eutrophication, all of which have significantly impacted the metabolic functions of corals and other marine organisms. Global warming has been identified as the main culprit in the decline of coral reefs. In response, we assessed the metabolic responses of one of the most iconic Caribbean corals to elevated temperatures. Accordingly, the proteomic profile of Acropora palmata was investigated during the cool dry and hot wet seasons of 2014 and 2015 in Puerto Rico using a combination of two-dimensional gel electrophoresis (2D-GE) and mass spectrometry. The study revealed that the average number of differentially abundant proteoforms between seasons was 527 in the inner-shelf reef at Enrique and 1,115 in the mid-shelf reef at San Cristobal, both located on the insular shelf of southwestern Puerto Rico. Our results show significant changes in A. palmata’s proteome, inducing alterations in key metabolic, enzymatic, translational, and apoptotic processes, between the cool dry and hot wet seasons. Quantitative real-time reverse transcription PCR (qRT-PCR) was used to validate the variation in the expression of five candidate stress-related genes under different seasonal temperatures. The findings highlight key proteoforms whose abundance varied with temperature, offering insight into A. palmata’s metabolic capacity to acclimate and respond to seasonal temperature fluctuations.

Antarctica, which has always been of great interest to researchers worldwide, is currently attracting considerable attention owing to climate change and other topics. In this context, bibliometric analysis allows the identification of hot topics, scientific productivity, cooperation, research gaps and strategic areas of potential interest. We conducted a bibliometric study to evaluate the global production of Antarctic research between 1980 and 2023 and analysed Spanish National Antarctic Programme (NAP) production as a case study. Scientific publications were reviewed and classified based on their main themes, key word co-occurrence and international collaborations. We found that scientific production worldwide and in the Spanish NAP has progressively increased since 1980. Globally, the main areas of research are the geosciences, oceanography and atmospheric sciences. However, the Spanish NAP, which reported 2287 publications, has focused more on the geosciences and ecology. Spanish Antarctic researchers have mainly collaborated with researchers from the USA, the UK, Germany and Italy. Our research highlights the importance of strengthening research plans to diversify and facilitate international collaboration, promoting a more interdisciplinary approach to address the current and future challenges identified by the scientific community. In this context, specific opportunities for developing a Spanish NAP strategic plan are discussed.

From December 2023 to November 2024, regular surveys were conducted to document finfish bycatch in the trawl fishery landing at Veraval Fishing Harbour, northeastern coast of the Arabian Sea. As an outcome of this exploration, three male specimens of Callionymus gardineri and five (four males and one female) specimens of C. omanensis were collected. Both species were recorded for the first time from the north-western Arabian Sea, coastal waters of India, accompanied by a new maximum length record for C. omanensis (Lmax = 122.1 mm standard length). Callionymus omanensis was originally described based on a single male specimen, whereas the description of female C. omanensis was interpreted. While the exact justification for their distribution in this new locality remains unknown, both dragonet species likely moved eastwards from their native habitats along the western Arabian Sea coast. This strongly suggests a significant research gap in our understanding of low-value deep-sea trawl bycatch, necessitating further exploration to improve biodiversity assessments. Herein, the detailed meristic counts and morphometric measurements are compared, and updated distributional information is collated.

Ostracoderms, Paleozoic jawless stem-gnathostomes, are characterized by distinctive bony shields covering the front of their bodies. These headshields exhibit significant variations in morphology across species, boasting frontal, lateral, and dorsal processes. Ostracoderms represent pivotal intermediaries between modern jawless and jawed vertebrates, so understanding their biology and ecology is crucial for unraveling the selective pressures that shaped the early evolution and diversification of jawed vertebrates, which now dominate vertebrate diversity. This study employs virtual paleontology techniques and phylogenetic comparative methods to explore the hydrodynamic and ecological implications of these processes, focusing on pteraspidomorphs, the most diverse ostracoderm group. The analysis reveals widespread convergence in the arrangement and development of headshield processes. Lateral processes enhance hydrodynamic efficiency and generate lift, while combined lateral and dorsal processes provide stability in rolling, yawing, and pitching. Frontal processes reduce drag in many cases. These findings illuminate the enigmatic roles of ostracoderm headshields, showing how the dimensions and arrangement of their processes are biomechanically linked to a range of functions and ecological roles. Collectively, this highlights the intricate evolutionary pathways of lifestyles and ecologies within stem-gnathostomes, challenging the idea of a unidirectional trend toward more active lifestyles in vertebrate evolution and suggesting diverse ecological roles for ostracoderms.