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We used morphological and molecular surveys to determine the presence or absence of Notodendrodes antarctikos and its congener, Notodendrodes hyalinosphaira, at diverse sites within McMurdo Sound, Antarctica. Morphological surveys were performed using shipboard box-core sampling, as well as handheld coring and visual inspection by divers in shallow (< 23 m) waters. Concurrent molecular analyses were performed using species- and genus-specific PCR primers on environmental DNA extracts. Both survey methods show that N. hyalinosphaira is widely distributed in the region but that N. antarctikos was not detected outside its originally reported range. The survey methods show complementary strengths and weaknesses, with morphological detection being more sensitive in areas where large and distinctive adult forms are present and with molecular detection being more effective for identification of presumed juvenile or propagule stages. Our results suggest that N. antarctikos is a highly endemic protist and may have one of the most restricted ranges ever reported for an Antarctic organism.

Conclusions: European national CPGs for diabetes provide limited recommendations on active CNO. All guidelines showcased deficits in their methodology, suggesting that more rigorous methods should be employed for diabetes CPG development across Europe.

The abyssal seafloor is a mosaic of highly diverse habitats that represent the least known marine ecosystems on Earth. Some regions enriched in natural resources, such as polymetallic nodules in the Clarion-Clipperton Zone (CCZ), attract much interest because of their huge commercial potential. Since nodule mining will be destructive, baseline data are necessary to measure its impact on benthic communities. Hence, we conducted an environmental DNA and RNA metabarcoding survey of CCZ biodiversity targeting microbial and meiofaunal eukaryotes that are the least known component of the deep-sea benthos. We analyzed two 18S rRNA gene regions targeting eukaryotes with a focus on Foraminifera (37F) and metazoans (V1V2), sequenced from 310 surface-sediment samples from the CCZ and other abyssal regions. Our results confirm huge unknown deep-sea biodiversity. Over 60% of benthic foraminiferal and almost a third of eukaryotic operational taxonomic units (OTUs) could not be assigned to a known taxon. Benthic Foraminifera are more common in CCZ samples than metazoans and dominated by clades that are only known from environmental surveys. The most striking results are the uniqueness of CCZ areas, both datasets being characterized by a high number of OTUs exclusive to the CCZ, as well as greater beta diversity compared to other abyssal regions. The alpha diversity in the CCZ is high and correlated with water depth and terrain complexity. Topography was important at a local scale, with communities at CCZ stations located in depressions more diverse and heterogeneous than those located on slopes. This could result from eDNA accumulation, justifying the interim use of eRNA for more accurate biomonitoring surveys. Our descriptions not only support previous findings and consolidate our general understanding of deep-sea ecosystems, but also provide a data resource inviting further taxon-specific and large-scale modeling studies. We foresee that metabarcoding will be useful for deep-sea biomonitoring efforts to consider the diversity of small taxa, but it must be validated based on ground truthing data or experimental studies.

Abstract Paleodictyon is one of the most iconic and widespread of trace fossils in the geological record. However, modern examples are less well known and restricted to deep-sea settings at relatively low latitudes. Here, we report the distribution of Paleodictyon at six abyssal sites near the Aleutian Trench. This study reveals for the first time the presence of Paleodictyon at Subarctic latitudes (51°–53°N) and at depths over 4500 m, although the traces were not observed at stations deeper than 5000 m suggesting that there is some bathymetric constraint for the trace maker. Two small Paleodictyon morphotypes were recognized (average mesh size of 1.81 cm), one having a central hexagonal pattern, the other being characterized by a non-hexagonal pattern. Within the study area, Paleodictyon shows no apparent correlation with local environmental parameters. Finally, based on a worldwide morphological comparison, we conclude that the new Paleodictyon specimens represent distinct ichnospecies that are associated with the relatively eutrophic conditions in this region. Their smaller size may reflect this more eutrophic setting in which sufficient food can be obtained from a smaller area in order to satisfy the energetic requirements of the tracemakers. If so, then Paleodictyon size may provide some assistance when interpreting paleoenvironmental conditions.

Some historians of the ‘Special Loan Collection of Scientific Apparatus’ exhibited in 1876 interpret its principal significance as catalysing the eventual transformation of science collections in the (South) Kensington Museum into London’s present-day Science Museum. Debates about that nexus have not, however, noted that this exhibition was an international crowd-sourced venture in public science. Far from being collection-founding donations, most artefacts displayed were discretionary loans contributed by private citizens, learned societies, instrument makers, universities, engineering companies and state departments from across both the UK and Europe, with most displayed items later returned to their exhibitors. Our paper draws upon the art historiography literature of ‘loan exhibitions’ to consider the 1876 exhibit in (mostly) physical science as part of a growing democratic tradition of resource sharing. This exhibitor-focused approach is illustrated via case studies of two kinds of contributors that did not predominantly have their loans converted to donations: (male) instrument makers and women, especially widows. In that context, we can interpret apparatus lending in 1876 as forms of advertising, memorialising, and just occasionally offloading disused but historically important equipment. It is in such terms that we can better understand why only a small fraction of loaned 1876 apparatus become permanent parts of the South Kensington science collections via such means as state departments discarding obsolete technical equipment.

Sub-Antarctic fjords are among the environments most affected by the recent climate change. In our dynamically changing world, it is essential to monitor changes in these vulnerable settings. Here, we present a baseline study of “living” (rose-bengal-stained) benthic foraminifera from fjords of South Georgia, including fjords with and without tidewater glaciers. Their distribution is analyzed in the light of new fjord water and sediment property data, including grain size and sorting, total organic carbon, total sulfur, and δ13C of bulk organic matter. Four well-defined foraminiferal assemblages are recognized. Miliammina earlandi dominates in the most restricted, near-shore and glacier-proximal habitats, Cassidulinoides aff. parkerianus in mid-fjord areas, and Globocassidulina aff. rossensis and an assemblage dominated by Ammobaculites rostratus, Reophax subfusiformis, and Astrononion echolsi are in the outer parts of the fjords. Miliammina earlandi can tolerate strong glacial influence, including high sedimentation rates in fjord heads and sediment anoxia, as inferred from sediment color and total organic carbon / sulfur ratios. This versatile species thrives both in the food-poor inner reaches of fjords that receive mainly refractory petrogenic organic matter from glacial meltwater and in shallow-water coves, where it benefits from an abundant supply of fresh, terrestrial, and marine organic matter. A smooth-walled variant of C. aff. parkerianus, apparently endemic to South Georgia, is the calcareous rotaliid best adapted to inner-fjord conditions characterized by moderate glacial influence and sedimentation rates and showing no preference for particular sedimentary redox conditions. The outer parts of fjords with clear, well-oxygenated bottom water are inhabited by G. aff. rossensis. Ammobaculites rostratus, R. subfusiformis, and A. echolsi dominate in the deepest-water settings, with water salinities ≥ 33.9 PSU and temperatures 0.2–1.4 ∘C, characteristic of winter water and Upper Circumpolar Deep Water. The inner- and mid-fjord foraminiferal assemblages seem specific to South Georgia, although with continued warming and deglaciation, they may become more widespread in the Southern Ocean.

Trait-based approaches that complement taxonomy-based studies have increased in popularity among the scientific community over the last decades. The collection of biological and ecological characteristics of species (i.e., traits) provides insight into species and ecosystem vulnerability to environmental and anthropogenic changes, as well as ecosystem functioning. Here, we present the FUN Azores trait database, describe our approach, evaluate its scope, compare it to other marine trait databases, and explore the spatial distribution of its traits with “functional maps.” While most of the available trait databases to date contain essential information to understand the functional diversity of a taxonomic or functional group, our ecosystem-based approach provides a comprehensive assessment of diverse fauna (i.e., meio-, macro-, and megafauna) from benthic and pelagic environments in the Azores Marine Park; including ridges, seamounts, hydrothermal vents, and the overlying water column. We used a collaborative approach involving 30 researchers with different expertise to develop the FUN Azores database, which contains compiled data on 14 traits representing morphological, behavioral, and life history characteristics for 1,210 species across 10 phyla. The “functional maps” show a distinct distribution of the two most common size classes, suggesting different communities with different functionalities. The following traits had the best scoring coverage (i.e., >95% of the species scored): maximum body size, body form, skeleton material, feeding structure, motility, environmental position, substratum affinity, distribution, and depth range; while traits related to species behavior (e.g., sociability or aggregation tendencies) and life history (e.g., developmental mechanism) had lower scoring coverage, highlighting the need for further research to fill these knowledge gaps. We found a larger number of species in the benthic compared to the pelagic environment and differing species composition between areas within the Azores Marine Park resulting from varying biodiversity, ecosystem types, sampling effort, and methodologies used. The FUN Azores database will foster and facilitate trait-based approaches in the area, develop a framework for expansion of cross-ecosystem and cross-taxa trait databases elsewhere, and improve our ecological understanding of the Azores Marine Park and its conservation requirements.

Charcot neuroarthropathy (CN) was first described over 150 years ago. Despite this there remains uncertanity around the factors that contribute to its development, and progression. This article will discuss the current controversies around the pathogenesis, epidemiology, diagnosis, assessment and management of the condition. The exact pathogenesis of CN is not fully understood, and it is likely to be multifactorial, with perhaps currently unknown mechanisms contributing to its development. Further studies are needed to examine opportunities to help screen for and diagnose CN. As a result of many of these factors, the true prevalence of CN is still largely unknown. Almost all of the recommendations for the assessment and treatment of CN are based on low-quality level III and IV evidence. Despite recommendations to offer people with CN nonremovable devices, currently only 40–50% people are treated with this type of device. Evidence is also lacking about the optimal duration of treatment; reported outcomes range from 3 months to more than a year. The reason for this variation is not entirely clear. A lack of standardised definitions for diagnosis, remission and relapse, heterogeneity of populations, different management approaches, monitoring techniques with unknown diagnostic precision and variation in follow-up times prevent meaningful comparison of outcome data. If people can be better supported to manage the emotional and physical consequences of CN, then this could improve people’s quality of life and well-being. Finally, we highlight the need for an internationally coordinated approach to research in CN.

OBJECTIVE: Diabetes affects 537 million people globally, with 34% expected to develop foot ulceration in their lifetime. Diabetes-related foot ulceration causes strain on health care systems worldwide, necessitating provision of high-quality evidence to guide their management. Given heterogeneity of reported outcomes, a core outcome set (COS) was developed to standardize outcome measures in studies assessing treatments for diabetes-related foot ulceration. RESEARCH DESIGN AND METHODS: The COS was developed using Core Outcome Measures in Effectiveness Trials (COMET) methodology. A systematic review and patient interviews generated a long list of outcomes that were rated by patients and experts using a nine-point Likert scale (from 1 [not important] to 9 [critical]) in the first round of the Delphi survey. Based on predefined criteria, outcomes without consensus were reprioritized in a second Delphi round. Critical outcomes and those without consensus after two Delphi rounds were discussed in the consensus meeting where the COS was ratified. RESULTS: The systematic review and patient interviews generated 103 candidate outcomes. The two consecutive Delphi rounds were completed by 336 and 176 respondents, resulting in an overall second round response rate of 52%. Of 37 outcomes discussed in the consensus meeting (22 critical and 15 without consensus after the second round), 8 formed the COS: wound healing, time to healing, new/recurrent ulceration, infection, major amputation, minor amputation, health-related quality of life, and mortality. CONCLUSIONS: The proposed COS for studies assessing treatments for diabetes-related foot ulceration was developed using COMET methodology. Its adoption by the research community will facilitate assessment of comparative effectiveness of current and evolving interventions. [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to determine the relationship between HbA1c variability and foot ulcer healing at 12 weeks and 12 months. Methods: Using National Diabetic Foot Care Audit (NDFA) and hospital records, demographics, baseline ulcer characteristics and healing outcomes for subjects presenting with a foot ulcer between 2017–2022 were collected at 12 weeks and 12 months. Subjects had diabetes duration > 3 years and ≥ 3 HbA1c recordings in the 5 years prior to presentation. Results: At 12 weeks, factors associated with an active ulcer were presence on hind foot (adjusted odds ratios) (2.1 [95% CI 1.3–3.7]), ischaemia (2.1 [95% CI:1.4–3.2]), area > 1 cm2 (2.7 [95% CI:1.7–4.2]) and diabetes duration > 24 years vs 3–10 (AOR 2.0 [95% CI 1.2–3.5]). After adjustment, HbA1c variability 6–10 mmol/mol and > 14.5 mmol/mol had AOR of 1.76 (95% CI 1.1–2.8; p = 0.0192) and 1.5 (95% CI 0.9–2.6; p = 0.1148) of an active ulcer at 12 weeks vs variability < 6 mmol/mol. At 12 months, ischaemia (AOR 2.4 [95% CI 1.5–3.8]) and diabetes duration > 24 years vs 3–10 years (AOR 3.3 [95% CI 1.7–6.4] were significant factors. HbA1c variability was not significant at 12 months. Conclusion: In keeping with the national NDFA data, in our cohort ulcer characteristics, but not HbA1c variability, were the key factors associated with ulcer healing at 12 weeks and 12 months. Plain Language Summary: Diabetes complications occur more frequently when glucose control is not as good as it could be. For a long time, HbA1c, or glycated haemoglobin, has been used as a measure of how well someone's diabetes has been controlled. However, another way of looking at diabetes control is to look at the changes of HbA1c over time—this is called glycaemic variability. Diabetes-related foot disease is one of the most feared complications of the condition, and our group has previously shown in a small study that glycaemic variability was associated with ulcer healing at 12 weeks—with lower variability leading to better healing. However, it did not consider other variables known to be associated with not being alive and ulcer free at 12 months. In the UK, data are collected as part of the National Diabetes Footcare Audit (NDFA). This dataset collects a lot of information on new foot ulcers and their outcomes 12 weeks later. We have used our centre's data to look at factors not included in the NDFA dataset—in particular glycaemic variability—to determine whether this influences ulcer outcomes at 12 weeks, but also at 12 months. We found that low glycaemic variability is associated with greater chances of healing but that the greatest association is the presence of poor blood flow and diabetes duration. [ABSTRACT FROM AUTHOR]

Trait-based approaches that complement taxonomy-based studies have increased in popularity among the scientific community over the last decades. The collection of biological and ecological characteristics of species (i.e., traits) provides insight into species and ecosystem vulnerability to environmental and anthropogenic changes, as well as ecosystem functioning. Here, we present the FUN Azores trait database, describe our approach, evaluate its scope, compare it to other marine trait databases, and explore the spatial distribution of its traits with "functional maps." While most of the available trait databases to date contain essential information to understand the functional diversity of a taxonomic or functional group, our ecosystem-based approach provides a comprehensive assessment of diverse fauna (i.e., meio-, macro-, and megafauna) from benthic and pelagic environments in the Azores Marine Park; including ridges, seamounts, hydrothermal vents, and the overlying water column. We used a collaborative approach involving 30 researchers with different expertise to develop the FUN Azores database, which contains compiled data on 14 traits representing morphological, behavioral, and life history characteristics for 1,210 species across 10 phyla. The "functional maps" show a distinct distribution of the two most common size classes, suggesting different communities with different functionalities. The following traits had the best scoring coverage (i.e., >95% of the species scored): maximum body size, body form, skeleton material, feeding structure, motility, environmental position, substratum affinity, distribution, and depth range; while traits related to species behavior (e.g., sociability or aggregation tendencies) and life history (e.g., developmental mechanism) had lower scoring coverage, highlighting the need for further research to fill these knowledge gaps. We found a larger number of species in the benthic compared to the pelagic environment and differing species composition between areas within the Azores Marine Park resulting from varying biodiversity, ecosystem types, sampling effort, and methodologies used. The FUN Azores database will foster and facilitate trait-based approaches in the area, develop a framework for expansion of crossecosystem and cross-taxa trait databases elsewhere, and improve our ecological understanding of the Azores Marine Park and its conservation requirements. [ABSTRACT FROM AUTHOR]

The abyssal Pacific Clarion Clipperton Zone (CCZ) hosts vast, commercially valuable seafloor deposits of polymetallic nodules. Foraminifera (testate protists) dominate benthic communities in this region. Here, we present a taxonomic survey, combining morphological and genetic data and focussing on mainly meiofauna-sized Foraminifera from the eastern CCZ. Sequences obtained from >100 specimens, the majority photographically documented, were analysed phylogenetically. Most were single-chambered Monothalamea (‘monothalamids’), a high percentage of them squatters inhabiting empty tests of mainly multi-chambered Foraminifera. The first sequences for the monothalamid genus Storthosphaera were obtained, while specimens assigned to Gloiogullmia, Hippocrepinella and Vanhoeffenella yielded new sequences. Among multichambered taxa, high-throughput Illumina sequencing (HTS) revealed a second haplotype of the calcareous rotaliid Oridorsalis umbonatus, possibly representing a distinct species. Additional HTS sequences were obtained from the rotaliids Nuttallides umbonifer and Globocassidulina subglobosa, confirming their wide distributions. We also obtained the first sequences for Cribrostomoides subglobosa, showing that it branches separately from other members of this genus. The fact that many sequences did not correspond to known morphospecies reflects the scarcity of reference barcodes for deep-sea Foraminifera, particularly the poorly known but highly diverse monothalamids. We recommend using HTS of single specimens to reveal further unknown species. Despite extensive research, much remains to be learnt about the true scale of foraminiferal biodiversity in the CCZ.

The task of inter-connecting artefacts within the broad category of ‘energy’ across multiple heritage collections raises very significant challenges. Energy per se is itself invisible, manifested only in a bewildering diversity of technological mediations of its acquisition, storage or transformation from one form to another (e.g. chemical to thermal, or electrical to motive). And while energy usage via such technology is easily linked to industrial growth and global prosperity, it is also entangled in multiple stories of human and environmental destruction over many centuries, albeit unevenly distributed over social class and global location. How then can the Congruence Engine project draw some coherent stories together from heritage collections that hold energy-related artefacts of so many kinds? Our paper explores how the Congruence Engine’s Energy team will approach this task by taking as our starting point two specific collections of Newcastle’s Discovery Museum: steam turbines and coal mining. Focusing on that particularly convenient pair of preliminary case studies enables us to look ahead to how we can bring the Congruence Engine project’s digital humanities tools more fully to bear in linking such energetic heritage to other (at least part) digitised collections of films, photographs, songs and journals, etc. In so doing, we highlight the need to address the broader cultural landscape of energy, often involving emotional human stories, that bring meaning to museum audiences’ engagement with energy’s material culture. And in contrast to traditional museum narratives of energy history as the technocratic ‘conquering’ of nature, we consider how the Congruence Engine project could help to bring in a complementary approach: memorialising energy history instead as a human drama entangled with many forms of human loss.

Abstract Aim This study aims to explore the feasibility of using serial MRI without contrast in the monitoring of Charcot neuroarthropathy to reduce duration of immobilisation of the foot, in order to decide whether a large‐scale trial is warranted. Methods A multicentre, randomised, prospective, two arm, open, feasibility study (CADOM) of people with diabetes with a suspected or confirmed diagnosis of Charcot neuroarthropathy. Participants were randomised (1:1) to ‘standard care plus', including repeated foot temperature measurements and X‐rays, or the intervention arm, with additional three‐monthly MRI, until remission of Charcot neuroarthropathy or a maximum 12 months (active phase). Participants were then followed‐up for a further 6 months, post remission to monitor for relapse of the Charcot neuroarthropathy (follow‐up phase). Feasibility outcomes were recruitment, retention, data completeness, adherence to study procedures and safety of the intervention MRI. We also collected clinical efficacy outcomes, this included time in cast/off‐loading device which will be the primary outcome of a future definitive trial. Finally, we collected patient reported outcomes, and data on health and social care usage. Results One‐hundred and five people were assessed for eligibility at five sites. 64/105 potential participants meet the eligibility criteria to participate in the study. Forty‐three participants were randomised: 20 to standard care plus and 23 to MRI intervention. The main reason for ineligibility was a previous episode of Charcot neuroarthropathy. Thirteen participants were withdrawn post‐randomisation due to an alternative diagnosis being made. Of the remaining 30 participants, 19 achieved remission, 6 had not gone into remission at the end of the 12 month active phase so exited the study. Five participants were lost to follow‐up. Of the MRIs that were not disrupted by COVID‐19 pandemic 26/31 (84%) were completed. For the visits that were conducted face‐to‐face, completion rates of patient‐reported outcome measures were between 71 and 100%. There were no safety incidents associated with the intervention MRI. As this was a feasibility study it was not designed to test the effectiveness of serial MRI in diagnosing remission. The time in cast/off‐loading device was 235 (±108.3) days for the standard care plus arm compared to 292 (±177.4) days for the intervention arm. There was no statistical difference in the time in cast/off‐loading device between the two arms of the study: Hazard Ratio (HR) 0.405 (95% CI 0.140–1.172), p = 0.096. Discussion The findings support a definitive randomised controlled trial to evaluate the effectiveness of MRI in diagnosing remission in Charcot neuroarthropathy. The rates of recruitment, retention, data, and MRI completeness show that a definitive study is feasible. Study registration ISRCTN, 74101606. Registered on 6 November 2017.

The abyssal plains are vast areas without large scale relief that occupy much of the ocean floor. Although long considered relatively featureless, they are now known to display substantial biological heterogeneity across different spatial scales. Ecological research in these regions benefits increasingly from non-destructive visual sampling of epifaunal organisms with imaging technology. We analysed images from ultra-high-definition towed camera transects at depths of around 3500 m across three stations (100–130 km apart) in the Bering Sea, to ask whether the density and distribution of visible epifauna indicated any substantial heterogeneity. We identified 71 different megafaunal taxa, of which 24 occurred at only one station. Measurements of the two most abundant faunal elements, the holothurian Elpidia minutissima and two xenophyophores morphotypes (the more common identifiable as Syringammina limosa), indicated significant differences in local densities and patchy aggregations that were strikingly dissimilar among stations. One station was dominated by xenophyophores, one was relatively depauperate in both target taxa as well as other identified megafauna, and the third station was dominated by Elpidia. This is an unexpected level of variation within comparable transects in a well-mixed oceanic basin, reinforcing the emerging view that abyssal habitats encompass biological heterogeneity at similar spatial scales to terrestrial continental realms.

Benthic foraminifera cannot be sampled adequately using a single device. Smaller taxa are best collected using multicorers, the larger with box corers, but towed devices (dredges, trawls and epibenthic sledges) also retain many larger species. Here, we describe macrofaunal (>300 µm) foraminiferal assemblages obtained using an epibenthic sledge (EBS) in the Clarion-Clipperton Zone (eastern equatorial Pacific), a region hosting seafloor deposits of polymetallic nodules. Twelve EBS samples were collected in four areas licenced for exploration by the International Seabed Authority (ISA) to German, IOM, Belgium and French contractors, and to APEI-3, one of the protected Areas of Special Scientific Interest designated by the ISA. We recognised 280 morphospecies among 1954 specimens, with between 74 (IOM) and 121 (Belgium) in particular areas. Most (92.7%) were single-chambered monothalamids, of which 75 species (26.8%) belonged to the Komokioidea (‘komoki’), 47 (16.8%) to branched and unbranched tubes, 33 (11.8%) to chain-like and 32 (11.4%) to various ‘komoki-like’ forms. Fragments of megafaunal xenophyophores represented 21 species (7.50%), including Spiculammina delicata, previously reported only from the Russian area. Rarefaction curves and sample coverage completeness curves suggest that only a fraction of the macrofaunal foraminiferal diversity had been sampled. The occurrence of 71.8% of species in 1-2 of the 12 samples and 84.9% in 1-3 of the samples was a likely result of substantial undersampling. Dissimilarity in species composition between areas was very high: 64.2% (German vs IOM area) to 86.9% (German area vs APEI-3). Similarity within a single area was quite low: 29.1% (German) to 45.1% (IOM). In multidimensional scaling (MDS) plots, the APEI-3 area was clearly distinct in terms of faunal composition from all other areas, the French area somewhat separated from the German, IOM and Belgium areas, with the German and IOM samples being the most similar. These patterns may reflect the geographical separation of the French and APEI-3 areas and their location in deeper, more oligotrophic waters. Our study demonstrates that EBS samples from the eastern CCZ are a rich source of novel foraminiferal taxa, particularly light, easily resuspended komoki, providing a valuable perspective on foraminiferal biodiversity.

Abstract The Antarctic coastal fauna is characterized by high endemism related to the progressive cooling of Antarctic waters and their isolation by the Antarctic Circumpolar Current. The origin of the Antarctic coastal fauna could involve either colonization from adjoining deep-sea areas or migration through the Drake Passage from sub-Antarctic areas. Here, we tested these hypotheses by comparing the morphology and genetics of benthic foraminifera collected from Antarctica, sub-Antarctic coastal settings in South Georgia, the Falkland Islands and Patagonian fjords. We analyzed four genera (Cassidulina, Globocassidulina, Cassidulinoides, Ehrenbergina) of the family Cassidulinidae that are represented by at least nine species in our samples. Focusing on the genera Globocassidulina and Cassidulinoides, our results showed that the first split between sub-Antarctic and Antarctic lineages took place during the mid-Miocene climate reorganization, probably about 20 to 17 million years ago (Ma). It was followed by a divergence between Antarctic species ~ 10 Ma, probably related to the cooling of deep water and vertical structuring of the water-column, as well as broadening and deepening of the continental shelf. The gene flow across the Drake Passage, as well as between South America and South Georgia, seems to have occurred from the Late Miocene to the Early Pliocene. It appears that climate warming during 7–5 Ma and the migration of the Polar Front breached biogeographic barriers and facilitated inter-species hybridization. The latest radiation coincided with glacial intensification (~ 2 Ma), which accelerated geographic fragmentation of populations, demographic changes, and genetic diversification in Antarctic species. Our results show that the evolution of Antarctic and sub-Antarctic coastal benthic foraminifera was linked to the tectonic and climatic history of the area, but their evolutionary response was not uniform and reflected species-specific ecological adaptations that influenced the dispersal patterns and biogeography of each species in different ways.

The growing interest in mineral resources of the deep sea, such as seafloor massive sulphide deposits, has led to an increasing number of exploration licences issued by the International Seabed Authority. In the Indian Ocean, four licence areas exist, resulting in an increasing number of new hydrothermal vent fields and the discovery of new species. Most studies focus on active venting areas including their ecology, but the non-vent megafauna of the Central Indian Ridge and South East Indian Ridge remains poorly known.In the framework of the Indian Ocean Exploration project in the German license area for seafloor massive sulphides, baseline imagery and sampling surveys were conducted yearly during research expeditions from 2013 to 2018, using video sledges and Remotely Operated Vehicles.This is the first report of an imagery collection of megafauna from the southern Central Indian- and South East Indian Ridge, reporting the taxonomic richness and their distribution. A total of 218 taxa were recorded and identified, based on imagery, with additional morphological and molecular confirmed identifications of 20 taxa from 89 sampled specimens. The compiled fauna catalogue is a synthesis of megafauna occurrences aiming at a consistent morphological identification of taxa and showing their regional distribution. The imagery data were collected during multiple research cruises in different exploration clusters of the German licence area, located 500 km north of the Rodriguez Triple Junction along the Central Indian Ridge and 500 km southeast of it along the Southeast Indian Ridge.

Marine bacteria regulate fluxes of matter and energy essential for pelagic and benthic organisms and may also be involved in the formation and maintenance of commercially valuable abyssal polymetallic nodules. Future mining of these nodule fields is predicted to have substantial effects on biodiversity and physicochemical conditions in mined areas. Yet, the identity and distributions of bacterial populations in deep-sea sediments and associated polymetallic nodules has received relatively little attention. We examined bacterial communities using high-throughput sequencing of bacterial 16S rRNA gene fragments from samples collected in the water column, sediment, and polymetallic nodules in the Pacific Ocean (bottom depth ≥4,000 m) in the eastern Clarion-Clipperton Zone. Operational taxonomic units (OTUs; defined at 99% 16S rRNA gene identity) affiliated with JTB255 (Gammaproteobacteria) and Rhodospirillaceae (Alphaproteobacteria) had higher relative abundances in the nodule and sediment habitats compared to the water column. Rhodobiaceae family and Vibrio OTUs had higher relative abundance in nodule samples, but were less abundant in sediment and water column samples. Bacterial communities in sediments and associated with nodules were generally similar; however, 5,861 and 6,827 OTUs found in the water column were retrieved from sediment and nodule habitats, respectively. Cyanobacterial OTUs clustering among Prochlorococcus and Synechococcus were detected in both sediments and nodules, with greater representation among nodule samples. Such results suggest that vertical export of typically abundant photic-zone microbes may be an important process in delivery of water column microorganisms to abyssal habitats, potentially influencing the structure and function of communities in polymetallic nodule fields.