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1. Effect of captivity on the vertebral bone microstructure of xenarthran mammals

   https://doi.org/10.1002/ar.24817  

   Zack, Ellianna H.; Smith, Stephanie M.; Angielczyk, Kenneth D. (November 2021, The Anatomical Record)

   null (Ed.)

   Captive specimens in museum collections facilitate study of rare taxa, but the lifestyles, diets, and lifespans of captive animals differ from their wild counterparts. Trabecular bone architecture adapts to in vivo forces, and may reflect interspecific variation in ecology and behavior as well as intraspecific variation between captive and wild specimens. We compared trunk vertebrae bone microstructure in captive and wild xenarthran mammals to test the effects of ecology and captivity. We collected μCT scans of the last six presacral vertebrae in 13 fossorial, terrestrial, and suspensorial xenarthran species (body mass: 120 g to 35 kg). For each vertebra, we measured centrum length; bone volume fraction (BV.TV); trabecular number and mean thickness (Tb.Th); global compactness (GC); cross-sectional area; mean intercept length; star length distribution; and connectivity and connectivity density. Wild specimens have more robust trabeculae, but this varies with species, ecology, and pathology. Wild specimens of fossorial taxa (Dasypus) have more robust trabeculae than captives, but there is no clear difference in bone microstructure between wild and captive specimens of suspensorial taxa (Bradypus, Choloepus), suggesting that locomotor ecology influences the degree to which captivity affects bone microstructure. Captive Tamandua and Myrmecophaga have higher BV.TV, Tb.Th, and GC than their wild counterparts due to captivity-caused bone pathologies. Our results add to the understanding of variation in mammalian bone microstructure, suggest caution when including captive specimens in bone microstructure research, and indicate the need to better replicate the habitats, diets, and behavior of animals in captivity. 

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2. From e-voucher to genomic data: Preserving archive specimens as demonstrated with medically important mosquitoes (Diptera: Culicidae) and kissing bugs (Hemiptera: Reduviidae)

   https://doi.org/10.1371/journal.pone.0247068  

   Andrade Justi, Silvia; Soghigian, John; Pecor, David B.; Caicedo-Quiroga, Laura; Rutvisuttinunt, Wiriya; Li, Tao; Stevens, Lori; Dorn, Patricia L.; Wiegmann, Brian; Linton, Yvonne-Marie (February 2021, PLOS ONE)

   Oliveira, Pedro L. (Ed.)

   Scientific collections such as the U.S. National Museum (USNM) are critical to filling knowledge gaps in molecular systematics studies. The global taxonomic impediment has resulted in a reduction of expert taxonomists generating new collections of rare or understudied taxa and these large historic collections may be the only reliable source of material for some taxa. Integrated systematics studies using both morphological examinations and DNA sequencing are often required for resolving many taxonomic issues but as DNA methods often require partial or complete destruction of a sample, there are many factors to consider before implementing destructive sampling of specimens within scientific collections. We present a methodology for the use of archive specimens that includes two crucial phases: 1) thoroughly documenting specimens destined for destructive sampling—a process called electronic vouchering, and 2) the pipeline used for whole genome sequencing of archived specimens, from extraction of genomic DNA to assembly of putative genomes with basic annotation. The process is presented for eleven specimens from two different insect subfamilies of medical importance to humans: Anophelinae (Diptera: Culicidae)—mosquitoes and Triatominae (Hemiptera: Reduviidae)—kissing bugs. Assembly of whole mitochondrial genome sequences of all 11 specimens along with the results of an ortholog search and BLAST against the NCBI nucleotide database are also presented. 

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3. Current status of freshwater red algal diversity (Rhodophyta) of the African continent including description of new taxa (Batrachospermales)

   https://doi.org/10.1080/00318884.2020.1732149  

   Szinte, Amanda L.; Taylor, Jonathan C.; Abosede, Adesalu T.; Vis, Morgan L. (April 2020, Phycologia)

   Freshwater red algae have been collected on the African continent since the early 1800s. However, the collections have been sparse and geographically restricted. The present study sought to bring together information from the literature, herbarium specimens, and newly collected specimens to provide an updated assessment of the freshwater red algal diversity of the African continent with a focus on the species-rich Batrachospermales. DNA sequence data and morphological observations were conducted for recently collected specimens. From these analyses, four new taxa are proposed: Kumanoa bouwmanii, Sheathia murpheyi, Sirodotia kennedyi, and the form taxon ‘Chantransia azurea’. DNA sequence data had been previously published for Kumanoa iriomotensis, Sirodotia aff. huillensis, and S. suecica. With this study, we have added sequence data for Torularia atra as well as a second location for S. suecica. In total, there are eight taxa with sequence data, of which five appear to be endemic. From our assessment of literature reports and herbarium specimens, we conclude that Kumanoa, Sirodotia, and Torularia have often been collected and are relatively geographically widespread with two or more species present. In addition, Montagnia, Nothocladus, Paralemanea, Sheathia, and Visia as well as Batrachospermum section Gonimopropagulum are represented in the flora. We estimate that 14 to 19 batrachospermalean taxa can be recognised for the African flora, and that with more study, that number could easily double or triple based on the diversity known from other well-studied continents. 

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4. Effects of captivity on the bone microstructure of xenarthrous vertebrae

   Zack, Ellianna H; Smith, Stephanie M; Angielczyk, Kenneth D (March 2021, Integrative and comparative biology)

   Captive specimens in natural history collections allow researchers to inspect the morphologies of rare taxa, but the lifestyles,diets, and lifespans of captive animals differ from those of their wild counterparts. To quantify these differences, we compared bone microstructure of trunk vertebrae in captive and wild xenarthran mammals (sloths, armadillos, anteaters). Because trabecular bone architecture (TBA) adapts to in vivo forces, bone microstructure reflects ecology and behavior, but this means that it may differ between captive and wild specimens of the same species. We collected μCT scans of the last six presacral vertebrae in 13 species of fossorial, terrestrial, and suspensorial xenarthrans ranging in body mass from 120g (Chlamyphorus) to 35kg (Myrmecophaga). For each vertebra, we measured bone volume fraction (BVF); trabecular number, mean thickness (TbTh), and orientation; global compactness; and cross sectional area. Wild specimens generally have more robust trabeculae, but this differs based on species, vertebral position, ecology, and pathology. The wild specimens of fossorial taxa (Dasypus) have more robust trabeculae than their captive counterparts, but there is no clear difference in TBA of wild and captive specimens in suspensorial and terrestrial taxa (Bradypus, Choloepus, Cyclopes). These data suggest that locomotor ecology affects the level to which captivity affects bone microstructure. The captive specimens of both Tamandua and Myrmecophaga have higher BVF and TbTh than their wild counterparts, indicating more brittle trabeculae due to bone pathologies caused by captivity. Our results add to the overall understanding of variation in mammalian bone microstructure and suggest caution when including captive specimens in research on TBA. 

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5. The Herbarium 2021 Half-Earth Challenge Dataset

   de Lutio, Riccardo; Little, Damon; Ambrose, Barbara; Belongie, Serge (January 2021, FGVC8 Workshop at CVPR 2021)

   Herbarium sheets present a unique view of the world's botanical history, evolution, and diversity. This makes them an all-important data source for botanical research. With the increased digitisation of herbaria worldwide and the advances in the fine-grained classification domain that can facilitate automatic identification of herbarium specimens, there are a lot of opportunities for supporting research in this field. However, existing datasets are either too small, or not diverse enough, in terms of represented taxa, geographic distribution or host institutions. Furthermore, aggregating multiple datasets is difficult as taxa exist under a multitude of different names and the taxonomy requires alignment to a common reference. We present the Herbarium Half-Earth dataset, the largest and most diverse dataset of herbarium specimens to date for automatic taxon recognition. https://doi.org/10.48550/arXiv.2105.13808 

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