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Drillholes made by naticid and muricid gastropods are frequently used in evolutionary and ecological studies because they provide direct, preservable evidence of predation. The muricid Ecphora is common in many Neogene Atlantic Coastal Plain assemblages in the United States, but is frequently ignored in studies of naticid predation. We used a combination of Pliocene fossil, modern beach, and experimentally derived samples to evaluate the hypothesis that Ecphora was an important source of drillholes in infaunal bivalve prey shared with naticids. We focused on the large, thick-shelled venerid, Mercenaria, which is commonly drilled by naticids today. Laboratory experiments, modern beach samples, and the published literature confirm that naticids preferentially drill near the umbo (significant clumping of holes), show a significant correlation between prey size and predator size (estimated by outer borehole diameter), and prefer Mercenaria <50 mm antero-posterior width when other prey are present. Fossil samples containing Ecphora (with or without other large muricids) show no drillhole site stereotypy (no significant clumping, greater variability in placement), no significant predator: prey size correlation, drilled prey shells larger than the largest modern naticids could produce in an experimental setting, and drillholes larger in diameter than those estimated for the largest Pliocene naticids, thus supporting our hypothesis. Substantial overlap in the placement of holes drilled by naticids and muricids, however, made identifying predators from drillhole position problematic. The lack of overlapping ranges of prey shell thickness between fossil and other samples precluded the use of drill- hole morphology to establish predator identity (e.g., ratio of inner borehole diameter to outer borehole diameter, drillhole angle). Whereas the difficulty in determining predator identity from drillholes limits the types of analyses that can be reliably performed in mixed-predator assemblages, recognizing Ecphora as a prominent drilling predator creates the opportunity to investigate previously unrecognized questions.

A polychaete from the Middle Devonian Arkona Shale at Hungry Hollow, Arkona, Ontario is preserved in three dimensions in pyrite. The prostomium bears a single median antenna, a pair of lateral antennae and a pair of ventral palps. It is assumed to be fused to a reduced peristomium. The anteriormost three pairs of trunk appendages are modified as tentacular cirri, the third long and biramous. The remainder of the finely annulated trunk bears at least 21 similar biramous parapodia, some of which preserve evidence of chaetae. The postsegmental pygidium is very small and may bear up to two pairs of cirri. The polychaete, Arkonips topororum, falls within the Palpata, Aciculata, among the crown group Phyllodocida. Its remarkable preservation highlights the potential of the Arkona Shale to yield other examples of soft-tissue preservation.

Olenid trilobites are characteristic of low-oxygen environments in the early Paleozoic, and researchers have proposed that olenids may have harbored chemoautotrophic symbionts, allowing them to live in borderline sulfidic environments. Beds with soft-tissue preservation at the Beecher's Trilobite Bed site in the Frankfort Shale and the Martin Quarry in the Whetstone Gulf Formation (both Ordovician, New York State) are dominated by the olenid Triarthrus. A bed-by-bed analysis of the sedimentology, taphonomy, paleoecology, and ichnology demonstrates that the exceptionally preserved organisms did not undergo extensive transport, and that the intervals bearing Triarthrus accumulated predominantly in the lower part of the dysaerobic zone. These intervals contain a low-diversity benthic fauna occurring in relatively low abundance, and consisting primarily of small brachiopods and trilobites. The taphonomy, in particular localized pyritization, the associated fauna, and the distribution of Triarthrus elsewhere in the Taconic foreland basin demonstrate that the environments in which Triarthrus lived were not sulfidic, and that these trilobites were unlikely to have adopted a chemoautotrophic mode of life.

A geologically rapid Neoproterozoic oxygenation event is commonly linked to the appearance of marine animal groups in the fossil record. However, there is still debate about what evidence from the sedimentary geochemical record—if any—provides strong support for a persistent shift in surface oxygen immediately preceding the rise of animals. We present statistical learning analyses of a large dataset of geochemical data and associated geological context from the Neoproterozoic and Palaeozoic sedimentary record and then use Earth system modelling to link trends in redox-sensitive trace metal and organic carbon concentrations to the oxygenation of Earth’s oceans and atmosphere. We do not find evidence for the wholesale oxygenation of Earth’s oceans in the late Neoproterozoic era. We do, however, reconstruct a moderate long-term increase in atmospheric oxygen and marine productivity. These changes to the Earth system would have increased dissolved oxygen and food supply in shallow-water habitats during the broad interval of geologic time in which the major animal groups first radiated. This approach provides some of the most direct evidence for potential physiological drivers of the Cambrian radiation, while highlighting the importance of later Palaeozoic oxygenation in the evolution of the modern Earth system. Oxygen in shallow shelf waters rose linearly with atmospheric oxygen in the Neoproterozoic era, potentially driving the first radiation of marine animals, but widespread ocean oxygenation came later, according to reconstructions of oxygen levels and marine productivity.

Georeferencing is the process of aligning a text description of a geographic location with a spatial location based on a geographic coordinate system. Training aids are commonly created around the georeferencing process to disseminate community standards and ideas, guide accurate georeferencing, inform users about new tools, and help users evaluate existing geospatial data. The Georeferencing for Research Use (GRU) workshop was implemented as a training aid that focused on the creation and research use of geospatial coordinates, and included both data researchers and data providers, to facilitate communication between the groups. The workshop included 23 participants with a wide background of expertise ranging from students (undergraduate and graduate), professors, researchers and educators, scientific data managers, natural history collections personnel, and spatial analyst specialists. The conversations and survey results from this workshop demonstrate that it is important to provide opportunities for biocollections data providers to interact directly with the researchers using the data they produce and vice versa.

Visual function in young IDDM patients over 8 years of age. A 4-year longitudinal study. R V North , U Farrell , D Banford , C Jones , J W Gregory , G Butler and D R Owens Department of Optometry and Vision Sciences, University of Wales, Cardiff, U.K. north@cardiff.ac.uk Abstract OBJECTIVE: To carry out a longitudinal study of visual functions in young patients over the age of 8 years with IDDM and to assess the impact of metabolic control on the presence of diabetic retinopathy. RESEARCH DESIGN AND METHODS: There were 37 young IDDM patients from the Paediatric and Adolescent Clinic at the University Hospital of Wales studied annually for 4 years, with a control group of 24 healthy subjects observed over a 2-year period. Assessment of visual functions included visual acuity, color vision, and contrast sensitivity. Ophthalmoscopy and retinal photography were used to determine the presence or absence of diabetic retinopathy. In addition, pubertal status and metabolic control (glycosylated hemoglobin) were determined at each visit. RESULTS: Patients with IDDM demonstrate abnormal color vision and contrast sensitivity compared with the control group (P < 0.05), but visual acuity was unaffected. Visual functions were not significantly different between those IDDM patients with and without retinopathy. After 4 years, diabetic retinopathy was present in 43% of the group and was related to diabetes duration and metabolic control (P < 0.05). CONCLUSIONS: Visual function testing could not distinguish between those IDDM patients with and without retinopathy, but the color vision and contrast sensitivity in those with IDDM were significantly impaired compared with the control group. The presence of retinopathy was related to the duration of diabetes and metabolic control. It is important to ensure that good glycemic control and regular attendance for retinopathy screening is encouraged in the adolescent patients.