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Biomineralization refers to the biological processes through which living organisms produce minerals. In recent years, biomineralizing microorganisms have been used to stabilize soil or to impart a self-healing or self-sealing mechanism to damaged cement and concrete materials. However, applications of biominerals in cement and concrete research can extend far beyond these applications. This article focuses on the biomineralization of calcium carbonate (CaCO3) and silicon dioxide (SiO2) and their past, present, and future potential applications in cement and concrete research. First, we review the mechanisms of CaCO3 and SiO2 biomineralization and the micro- and macroorganisms involved in their production. Second, we showcase the wide array of biomineral architectures, with an explicit focus on CaCO3 polymorphs and SiO2 morphologies found in nature. Third, we briefly summarize previous applications of CaCO3 and SiO2 biomineralization in cement and concrete research. Finally, we discuss emerging applications of biominerals in cement and concrete research, including mineral admixtures or raw meal for portland cement production, as well as other applications that extend beyond self-healing. 

ABSTRACT Tiger moth species vary greatly in the number of clicks they produce and the resultant duty cycle. Signals with higher duty cycles are expected to more effectively interfere with bat sonar. However, little is known about the minimum duty cycle of tiger moth signals for sonar jamming. Is there a threshold that allows us to classify moths as acoustically aposematic versus sonar jammers based on their duty cycles? We performed playback experiments with three wild-caught adult male bats, Eptesicus fuscus. Bat attacks on tethered moths were challenged using acoustic signals of Bertholdia trigona with modified duty cycles ranging from 0 to 46%. We did not find evidence for a duty cycle threshold; rather, the ability to jam the bat's sonar was a continuous function of duty cycle consistent with a steady increase in the number of clicks arriving during a critical signal processing time window just prior to the arrival of an echo. The proportion of successful captures significantly decreased as the moth duty cycle increased. Our findings suggest that moths cannot be unambiguously classified as acoustically aposematic or sonar jammers based solely on duty cycle. Bats appear to compensate for sonar jamming by lengthening the duration of their terminal buzz and they are more successful in capturing moths when they do so. In contrast to previous findings for bats performing difficult spatial tasks, the number of sonar sound groups decreased in response to high duty cycles and did not affect capture success. 

Native bee species in the United States provide invaluable pollination services. Concerns about native bee declines are growing, and there are calls for a national monitoring program. Documenting species ranges at ecologically meaningful scales through coverage completeness analysis is a fundamental step to track bees from species to communities. It may take decades before all existing bee specimens are digitized, so projections are needed now to focus future research and management efforts. From 1.923 million records, we created range maps for nearly 88% (3158 species) of bee species in the contiguous United States, provided the first analysis of inventory completeness for digitized specimens of a major insect clade, and perhaps most important, estimated spatial completeness accounting for all known bee specimens in USA collections, including undigitized bee specimens. Completeness analyses were very low (3–37%) across four examined spatial resolutions when using the currently available bee specimen records. Adding a subset of observations from community science data sources did not significantly increase completeness, and adding a projected 4.7 million undigitized specimens increased completeness by only an additional 12–13%. Assessments of data, including projected specimen records, indicate persistent taxonomic and geographic deficiencies. In conjunction with expedited digitization, new inventories that integrate community science data with specimen‐based documentation will be required to close these gaps. A combined effort involving both strategic inventories and accelerated digitization campaigns is needed for a more complete understanding of USA bee distributions. 

Taxonomy is foundational to all biological sciences. Names allow us to organize and communicate information about biological groups. This process is critical for understanding and preserving the biodiversity of our planet. There are an estimated 8.7 million extant eukaryotes (Mora et al. 2011) and possibly as many as 1 trillion microbial species (Locey and Lennon 2016), with untold numbers of extinct taxa yet to be discovered in the fossil record. Accounting for all these taxa and maintaining their nomenclatural resources is one of the great challenges in biology. A few major hurdles in overcoming this challenge are the inability to find, share, and update taxonomic resources efficiently in real time. Efforts to standardize and continually update taxonomic names in a sustainable way have been limited. The problem is complex, and solutions must deal with the large backlog of names, a constant stream of new names, the confusing merging and splitting of taxonomic synonyms, the subjective nature of taxonomic concepts, and the fundamental limitations on available expertise and curators' time to prepare and maintain such resources. Hyperdiverse groups such as arthropods are especially challenging as there are relatively few experts on any given lineage and changes in taxonomy can be rapid as new species are continually being discovered and described. After struggling to wrangle taxonomic resources in support of specimen digitization efforts, I began development of TaxoTracker as a proof-of-concept, web-based platform for facilitating expert curation and dissemination of biological taxonomies. TaxoTracker is still in development, but its current and planned functionalities will be shown through a combination of demonstration and discussion. TaxoTracker identifies and implements features that attempt to simplify the production and maintenance of expert-curated resources, while also limiting the responsibilities that are placed on individual experts who are often already overburdened and underfunded. These features include: Centralized, searchable, and easily obtained resources in useful formats Community-driven, citation-based curatorial suggestions Expert-reviewed curatorial recommendations Consensus-driven curatorial decisions Effort tracking and credit for suggestions and reviews Centralized, searchable, and easily obtained resources in useful formats Community-driven, citation-based curatorial suggestions Expert-reviewed curatorial recommendations Consensus-driven curatorial decisions Effort tracking and credit for suggestions and reviews 

Over 300 million arthropod specimens are housed in North American natural history collections. These collections represent a “vast hidden treasure trove” of biodiversity −95% of the specimen label data have yet to be transcribed for research, and less than 2% of the specimens have been imaged. Specimen labels contain crucial information to determine species distributions over time and are essential for understanding patterns of ecology and evolution, which will help assess the growing biodiversity crisis driven by global change impacts. Specimen images offer indispensable insight and data for analyses of traits, and ecological and phylogenetic patterns of biodiversity. Here, we review North American arthropod collections using two key metrics, specimen holdings and digitization efforts, to assess the potential for collections to provide needed biodiversity data. We include data from 223 arthropod collections in North America, with an emphasis on the United States. Our specific findings are as follows: (1) The majority of North American natural history collections (88%) and specimens (89%) are located in the United States. Canada has comparable holdings to the United States relative to its estimated biodiversity. Mexico has made the furthest progress in terms of digitization, but its specimen holdings should be increased to reflect the estimated higher Mexican arthropod diversity. The proportion of North American collections that has been digitized, and the number of digital records available per species, are both much lower for arthropods when compared to chordates and plants. (2) The National Science Foundation’s decade-long ADBC program (Advancing Digitization of Biological Collections) has been transformational in promoting arthropod digitization. However, even if this program became permanent, at current rates, by the year 2050 only 38% of the existing arthropod specimens would be digitized, and less than 1% would have associated digital images. (3) The number of specimens in collections has increased by approximately 1% per year over the past 30 years. We propose that this rate of increase is insufficient to provide enough data to address biodiversity research needs, and that arthropod collections should aim to triple their rate of new specimen acquisition. (4) The collections we surveyed in the United States vary broadly in a number of indicators. Collectively, there is depth and breadth, with smaller collections providing regional depth and larger collections providing greater global coverage. (5) Increased coordination across museums is needed for digitization efforts to target taxa for research and conservation goals and address long-term data needs. Two key recommendations emerge: collections should significantly increase both their specimen holdings and their digitization efforts to empower continental and global biodiversity data pipelines, and stimulate downstream research. 

Abstract Anchored hybrid enrichment (AHE) has emerged as a powerful tool for uncovering the evolutionary relationships within many taxonomic groups. AHE probe sets have been developed for a variety of insect groups, though none have yet been shown to be capable of simultaneously resolving deep and very shallow (e.g., intraspecific) divergences. In this study, we present NOC1, a new AHE probe set (730 loci) for Lepidoptera specialized for tiger moths and assess its ability to deliver phylogenetic utility at all taxonomic levels. We test the NOC1 probe set with 142 individuals from 116 species sampled from all the major lineages of Arctiinae (Erebidae), one of the most diverse groups of noctuoids (>11 000 species) for which no well‐resolved, strongly supported phylogenetic hypothesis exists. Compared to previous methods, we generally recover much higher branch support (BS), resulting in the most well‐supported, well‐resolved phylogeny of Arctiinae to date. At the most shallow‐levels, NOC1 confidently resolves species‐level and intraspecific relationships and potentially uncovers cryptic species diversity within the genusHypoprepia. We also implement a ‘sensitivity analysis’ to explore different loci combinations and site sampling strategies to determine whether a reduced probe set can yield results similar to those of the full probe set. At both deep and shallow levels, only 50–175 of the 730 loci included in the complete NOC1 probe set were necessary to resolve most relationships with high confidence, though only when the more rapidly evolving sites within each locus are included. This demonstrates that AHE probe sets can be tailored to target fewer loci without a significant reduction in BS, allowing future studies to incorporate more taxa at a lower per‐sample sequencing cost. NOC1 shows great promise for resolving long‐standing taxonomic issues and evolutionary questions within arctiine lineages, one of the most speciose clades within Lepidoptera.