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Natural history collections assembled before modern‐day, anthropogenic declines in species occurrence and abundance can provide essential data for conservation and biogeographic research. Digitizing old, commonly ‘orphaned’ collections in small institutions without professional curators increases local community access to specimens, as well as global access to digitized data. We present a case study, documenting a 19th century freshwater mussel (Order: Unionoida) collection, which is part of the 'orphaned' natural history collections at Wesleyan University (Middletown, CT, USA). We curated this collection by identifying specimens according to present taxonomic practices, and using archival documents to recover metadata. Nearly 1900 specimens in 402 ‘lots’, representing 155 species, were photographed and catalogued. Three primary type specimens were identified; 64 species are on the IUCN Red List, with 4 extinct, and 28 Critically‐Endangered to Endangered. We created and publicly host online 3D models of imperiled species. These models enabled us to organize an exhibit of 3D prints of fragile specimens, and to study ecophenotypic variation of freshwater mussels along a river gradient. Our project documents the challenges and achievements of a case study illuminating the potential scientific value of, and revival strategies for, orphaned natural history collections.

 

In this paper, we demonstrate the suitability, sensitivity, and precision of low‐cost and easy‐to‐use ion‐selective electrodes (ISEs) for concurrent detection of NH4+ and NO3‐ in soil and water by technical and non‐technical end‐users to enable efficient soil and water management exposed to chronic reactive nitrogen loading. We developed a simplified methodology for sample preparation followed by the demonstration of an analytical methodology resulting in improvements of sensitivity and precision of ISEs. Herein, we compared and contrasted ISEs with traditional laboratory‐based technique such as Flow Injection Analysis (FIA) and portable colorimetric assay followed by comparisons of linear regression and Bayesian nonlinear calibration approaches applied on both direct potentiometry and standard addition modes of analysis in terms of in‐field applications and improvement of sensitivity and precision. The ISEs were validated for sensing on a range of ambient soil and water samples representing a range of NH4+ and NO3‐ concentrations from pristine to excessive saturation conditions. Herein developed methodology showed excellent agreement with lab‐based and portable analytical techniques while demonstrating improvements in precision and sensitivity analysis illustrated by a decrease in confidence intervals by 50‐60%. We also demonstrated the utilization of the entire ISE response curve thus removing the biases originating from linear approximation which is often currently employed. Therefore, we show that ISEs are robust yet low cost and an easy to use technology that can enable high‐frequency measurement of mineral N and help to improve our understanding of N transformation processes as influenced by soil management, fertilization, land use, and climate change. 

The Paleocene‐Eocene Thermal Maximum (PETM, ∼56 Ma) presents a past analog for future global warming. Previous studies provided evidence for major loss of dissolved oxygen during the PETM, although understanding the degree and distribution of oxygen loss poses challenges. Magnetofossils produced by magnetotactic bacteria are sensitive to redox conditions in sediments and water columns, and have been used to reconstruct paleoredox conditions over a range of geological settings. Here, we present records of well‐preserved magnetofossils from cores along Walvis Ridge in the Southeast Atlantic that span the PETM across a depth transect (∼1,500–3,600 m paleodepth). Hysteresis, isothermal remanent magnetization curves, first‐order reversal curve diagrams, and low‐temperature magnetic measurements document large variations in magnetic properties of magnetofossils, which relate to time and water depth. Abundant magnetofossil grains are present within the studied sediments, and their morphologies change with paleodepth, as shown by transmission electron microscope observations. Magnetofossils from samples within the PETM onset at the deeper sites (∼2,600–3,600 m paleodepth) have lower coercivity values, a higher oxidation degree, and smaller grain sizes than those from shallower sites (∼1,500–1,800 m paleodepth), likely reflecting changes in paleoredox conditions at different paleodepths. We use the magnetofossil records to reconstruct relative changes in dissolved oxygen content at different water depths through the PETM, and suggest that ocean deoxygenation likely expanded downwards in the early stages of the PETM. We thus demonstrate the value of magnetofossil records for paleoenvironmental reconstructions over time and space, particularly for sediments that lack carbonate fossils.

 

Marine protists are integral to the structure and function of pelagic ecosystems and marine carbon cycling, with rhizarian biomass alone accounting for more than half of all mesozooplankton in the oligotrophic oceans. Yet, understanding how their environment shapes diversity within species and across taxa is limited by a paucity of observations of heritability and life history. Here, we present observations of asexual reproduction, morphologic plasticity, and ontogeny in the planktic foraminifer Neogloboquadrina pachyderma in laboratory culture. Our results demonstrate that planktic foraminifera reproduce both sexually and asexually and demonstrate extensive phenotypic plasticity in response to nonheritable factors. These two processes fundamentally explain the rapid spatial and temporal response of even imperceptibly low populations of planktic foraminifera to optimal conditions and the diversity and ubiquity of these species across the range of environmental conditions that occur in the ocean.