The Sirius Passet Lagerstätte (SP), Peary Land, North Greenland, occurs in black slates deposited at or just below storm wave base. It represents the earliest Cambrian microbial mat community with exceptional preservation, predating the Burgess Shale by 10 million years. Trilobites from the SP are preserved as complete, three‐dimensional, concave hyporelief external moulds and convex epirelief casts. External moulds are shown to consist of a thin veneer of authigenic silica. The casts are formed from silicified cyanobacterial mat material. Silicification in both cases occurred shortly after death within benthic cyanobacterial mats. Pore waters were alkali, silica‐saturated, high in ferric iron but low in oxygen and sulphate. Excess silica was likely derived from remobilized biogenic silica. The remarkable siliceous death mask preservation opens a new window on the environment and location of the Cambrian Explosion. This window closed with the appearance of abundant mat grazers later as the Cambrian Explosion intensified.

The size and reach of the genetic counseling profession have expanded on a global scale since the 1970s. Despite this growth, the profession of genetic counseling has remained demographically homogenous. Promoting a culture of inclusivity that supports visible and invisible diversity and leveraging that culture not only expands perspectives represented in the field, but also helps foster equity in genetic services. This report summarizes the formation, implementation, and outcomes of the 2019 Diversity and Inclusion Task Force (TF) of the National Society of Genetic Counselors (NSGC), including the group's responses to their allotted charges from the NSGC Board of Directors. The recommendations generated by the TF aim to aid in the (1) establishment of infrastructure for ongoing diversity, inclusion, and equity (DEI) work by collaborating with a DEI organizational expert and forming a DEI advisory group within the NSGC, (2) development of specific short‐term DEI initiatives, and (3) identification of seven areas of focus areas that must be addressed in order to create meaningful and measurable DEI improvements. The efficacy of these recommendations will depend on the consistency and creativity of implementation, shared responsibility, sufficient resources allocated to DEI initiatives, and measurable outcomes.

The Sirius Passet Lagerstätte of North Greenland contains the first exceptionally preserved mat-ground community of the Cambrian, dominated, in terms of abundance, by trilobites but particularly characterized by iconic arthropods and lobopods, some also occurring in the Burgess shale. High-resolution photography, scanning electron imaging and elemental mapping have been carried out on a variety of specimens of the non-mineralized arthropod Campanamuta mantonae (Budd 2011 J. Syst. Palaeontol. 9, 217–260 (doi:10.1080/14772019.2010.49264410.1080/14772019.2010.492644)) which has three-dimensional gut and muscle preservation. Results show that the guts contain a high concentration of calcium phosphate (approximating to the mineral francolite), whereas the adjacent muscles are silicified. This indicates a unique, tissue-specific taphonomy for this Cambrian taxon. We hypothesize that the precipitation of calcium phosphate in the guts occurs rapidly after death by ‘crystal seed’ processes in suboxic, slightly acidic conditions; critically, the gut wall remained intact during precipitation. We postulate that the calcium phosphate was derived from ingested cellular material. Silicification of the muscles followed as the localized water chemistry became saturated in silica, high in Fe2+, and low in oxygen and sulfate. We document here the unique occurrence of two distinct but mechanistically similar taphonomic pathways within a diverse suite of possibilities in an Early Cambrian Lagerstätte.

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