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THREE NEW SPECIES OF MACRATRIA NEWMAN, 1838 (COLEOPTERA: ANTHICIDAE) FROM ECUADOR AND PERU
Get PDFMacratria carbo sp. nov., M. pulmonaria sp. nov. (both – eastern Andes, Ecuador) and M. tambopata sp. nov. (south Amazonian lowlands, Peru), are described and illustrated based on material from the Natural History Museum, London.The attached file is the published version of the article.NHM Repositor
Magma recharge patterns control eruption styles and magnitudes at Popocatépetl volcano (Mexico)
No full textAbstract - Diffusion chronometry has produced petrological evidence that magma recharge in mafic to intermediate systems can trigger volcanic eruptions within weeks to months. However, less is known about longer-term recharge frequencies and durations priming magma reservoirs for eruptions. We use Fe-Mg diffusion modeling in orthopyroxene to show that the duration, frequency, and timing of pre-eruptive recharge at Popocatépetl volcano (Mexico) vary systematically with eruption style and magnitude. Effusive eruptions are preceded by 9–13 yr of increased recharge activity, compared to 15–100 yr for explosive eruptions. Explosive eruptions also record a higher number of individual recharge episodes priming the plumbing system. The largest explosive eruptions are further distinguished by an ~1 yr recharge hiatus directly prior to eruption. Our results offer valuable context for the interpretation of ongoing activity at Popocatépetl, and seeking similar correlations at other arc volcanoes may advance eruption forecasting by including constraints on potential eruption size and style.Copyright © 2022 The Authors. Gold Open Access: This paper is published under the terms of the CC-BY license. The attached file is the published version of the article.NHM Repositor
Long‐Distance Avian Migrants Fail to Bring 2.3.4.4b HPAI H5N1 Into Australia for a Second Year in a Row
Get PDFLetter to the journal editor.Copyright © 2024 The Authors. Influenza and Other Respiratory Viruses published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
Composite branch construction by dual autozooidal budding modes in hornerids (Bryozoa: Cyclostomatida)
Get PDFAbstract - Horneridae (Cyclostomatida: Cancellata) is a family of marine bryozoans that forms tree‐like colonies bearing functionally unilaminate branches. Colony development in this clade is not well understood. We used micro‐computed tomography and scanning electron microscopy to trace zooidal budding in Hornera from the ancestrula onwards. Results show that hornerid branches are constructed by dual zooidal budding modes occurring synchronously at two separate budding sites at the growing tips. Frontal autozooids bud from a multizooidal budding lamina. Lateral autozooids bud from discrete abfrontal budding loci by “exomural budding,” a previously undescribed form of frontal budding centered on hypostegal pores in interzooidal grooves on the colonial body wall. These two budding modes are integrated during primary branch morphogenesis, forming composite, developmentally bilaminate, branches. Patterns of exomural budding vary among hornerid taxa, and future studies of Cancellata taxonomy and phylogeny may benefit from morphological concepts presented here.© 2022 The Authors. Journal of Morphology published by Wiley Periodicals LLC. This is an open access article under the terms of the Creative Commons Attribution‐NonCommercial License, which permits use, distribution and reproduction in any
medium, provided the original work is properly cited and is not used for commercial purposes. The attached file is the published version of the article.NHM Repositor
Detection of locally adapted genomic regions in wild rice (Oryza rufipogon) using environmental association analysis
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Oryza rufipogon is the wild progenitor of cultivated rice Oryza sativa and exhibits high levels of genetic diversity across its distribution, making it a useful resource for the identification of abiotic stress–tolerant varieties and genes that could limit future climate-changed–induced yield losses. To investigate local adaptation in O. rufipogon, we analyzed single nucleotide polymorphism (SNP) data from a panel of 286 samples located across a diverse range of climates. Environmental association analysis (EAA), a genome-wide association study (GWAS)-based method, was used and revealed 15 regions of the genome significantly associated with various climate factors. Genes within these environmentally associated regions have putative functions in abiotic stress response, phytohormone signaling, and the control of flowering time. This provides an insight into potential local adaptation in O. rufipogon and reveals possible locally adaptive genes that may provide opportunities for breeding novel rice varieties with climate change–resilient phenotypes.Copyright © The Author(s) 2023. Published by Oxford University Press on behalf of The Genetics Society of America.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which
permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
Comparative transcriptomics and gene expression divergence associated with homoploid hybrid speciation in Argyranthemum
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Ecological isolation is increasingly thought to play an important role in speciation, especially for the origin and reproductive isolation of homoploid hybrid species. However, the extent to which divergent and/or transgressive gene expression changes are involved in speciation is not well studied. In this study, we employ comparative transcriptomics to investigate gene expression changes associated with the origin and evolution of two homoploid hybrid plant species, Argyranthemum sundingii and A. lemsii (Asteraceae). As there is no standard methodology for comparative transcriptomics, we examined five different pipelines for data assembly and analysing gene expression across the four species (two hybrid and two parental). We note biases and problems with all pipelines, and the approach used affected the biological interpretation of the data. Using the approach that we found to be optimal, we identify transcripts showing DE between the parental taxa and between the homoploid hybrid species and their parents; in several cases, putative functions of these DE transcripts have a plausible role in ecological adaptation and could be the cause or consequence of ecological speciation. Although independently derived, the homoploid hybrid species have converged on similar expression phenotypes, likely due to adaptation to similar habitats.Copyright © The Author(s) 2023. Published by Oxford University Press on behalf of The Genetics Society of America.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0/), which
permits unrestricted reuse, distribution, and reproduction in any medium, provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
Limited Niche Change After Dispersal From Africa by Leopards (Panthera pardus) Hundreds of Thousands of Years Ago
No full textABSTRACT
Aim
The leopard (Panthera pardus) is a generalist species inhabiting Africa and Asia, reflecting dispersal from an ancestral African range. When dispersal events occur, they can entail ecological differentiation and local adaptation. This study compares the bioclimatic niches of African and Asian leopard subspecies, to investigate whether they retained their ancestral ecology during dispersal from Africa, or adapted to novel conditions and shifted niche.
Location
Africa and Eurasia.
Methods
We assembled a database of leopard presences from public resources and associated them with bioclimatic variables to identify which are relevant in predicting the species' distribution. We constructed a species distribution model and compared distributions predicted from models based on presences from all subspecies, versus models built only using African leopard records. Finally, we used multivariate analysis to visualise the niche occupied by each subspecies in climate space, and calculated overlaps to assess ecological differentiation.
Results
The species distribution model trained only on African occurrences predicted most of the Asian range, but not the extension into more extreme environments such as the colder areas inhabited by several Northern Asian subspecies, and seasonal and rugged areas inhabited by Persian leopards. Niche overlaps suggest that Asian subspecies mostly retained their ancestral niche, but in some cases started to use climatic conditions that are not found in Africa. The Persian leopard is the only subspecies for which this expansion represents most of its current niche.
Main Conclusions
Despite some expansion into high altitude, seasonal environments in Northern Asian populations, the results suggest generally limited adaptation to novel climates after dispersal from Africa and little ecological differentiation among Asian leopard populations. This finding complements recent genetic studies that suggest limited genetic differentiation among Asian leopards. Resolving the relationships between taxonomy and biological differentiation is important due to its relevance for the conservation of the species.Copyright © 2025 The Author(s). Diversity and Distributions published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium,provided the original work is properly cited. The linked file is the published version of the article.NHM Repositor
The early Cambrian Kylinxia zhangi and evolution of the arthropod head
Get PDFThe early Cambrian Kylinxia zhangi occupies a pivotal position in arthropod evolution, branching from the euarthropod stem lineage between radiodonts (Anomalocaris and relatives) and "great-appendage" arthropods.1,2 Its combination of appendage and exoskeletal features is viewed as uniquely bridging the morphologies of so-called "lower" and "upper" stem-group euarthropods.3,4 Microtomographic study of new specimens of Kylinxia refines and corrects previous interpretation of head structures in this species. Phylogenetic analyses incorporating new data reinforce the placement of Kylinxia in the euarthropod stem group but support new hypotheses of head evolution. The head of Kylinxia is composed of six segments, as in extant mandibulates, e.g., insects.5 In Kylinxia, these are an anterior sclerite associated with an unpaired median eye and paired lateral eyes (thus three rather than five eyes as was previously described1), deutocerebral frontal-most appendages, and four pairs of biramous appendages (rather than two pairs of uniramous appendages). Phylogenetic trees suggest that a six-segmented head in the euarthropod crown group was already acquired by a common ancestor with Kylinxia. The segmental alignment and homology of spinose frontal-most appendages between radiodonts and upper stem-group euarthropods6,7,8,9,10 is bolstered by morphological similarities and inferred phylogenetic continuity between Kylinxia and other stem-group euarthropods.Copyright © 2023 Elsevier Inc. The attached file is the published version of the article.NHM Repositor
Frontiers in soil ecology—Insights from the World Biodiversity Forum 2022
Get PDFAbstract: Global change is affecting soil biodiversity and functioning across all terrestrial ecosystems. Still, much is unknown about how soil biodiversity and function will change in the future in response to simultaneous alterations in climate and land use, as well as other environmental drivers. It is crucial to understand the direct, indirect and interactive effects of global change drivers on soil communities and ecosystems across environmental contexts, not only today but also in the near future. This is particularly relevant for international efforts to tackle climate change like the Paris Agreement, and considering the failure to achieve the 2020 biodiversity targets, especially the target of halting soil degradation. Here, we outline the main frontiers related to soil ecology that were presented and discussed at the thematic sessions of the World Biodiversity Forum 2022 in Davos, Switzerland. We highlight multiple frontiers of knowledge associated with data integration, causal inference, soil biodiversity and function scenarios, critical soil biodiversity facets, underrepresented drivers, global collaboration, knowledge application and transdisciplinarity, as well as policy and public communication. These identified research priorities are not only of immediate interest to the scientific community but may also be considered in research priority programmes and calls for funding.Copyright © 2022 The Authors. Journal of Sustainable Agriculture and Environment published by Global Initiative of Crop Microbiome and Sustainable Agriculture and John Wiley & Sons Australia, Ltd.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.NHM Repositor
DeepBryo: A web app for AI‐assisted morphometric characterization of cheilostome bryozoans
Get PDFAbstract: Bryozoans are becoming an increasingly popular study system in macroevolutionary, ecological, and paleobiological research. Members of this colonial invertebrate phylum display an exceptional degree of division of labor in the form of specialized modules, which allows for the inference of individual allocation of resources to reproduction, defense, and growth using simple morphometric tools. However, morphometric characterizations of bryozoans are notoriously labored. Here, we introduce DeepBryo, a web application for deep‐learning‐based morphometric characterization of cheilostome bryozoans. DeepBryo is capable of detecting objects belonging to six classes and outputting 14 morphological shape measurements for each object. The users can visualize the predictions, check for errors, and directly filter model outputs on the web browser. DeepBryo was trained and validated on a total of 72,412 structures in six different object classes from images of 109 different families of cheilostome bryozoans. The model shows high (> 0.8) recall and precision for zooid‐level structures. Its misclassification rate is low (~ 4%) and largely concentrated in two object classes. The model's estimated structure‐level area, height, and width measurements are statistically indistinguishable from those obtained via manual annotation. DeepBryo reduces the person‐hours required for characterizing individual colonies to less than 1% of the time required for manual annotation. Our results indicate that DeepBryo enables cost‐, labor,‐ and time‐efficient morphometric characterization of cheilostome bryozoans. DeepBryo can greatly increase the scale of macroevolutionary, ecological, taxonomic, and paleobiological analyses, as well as the accessibility of deep‐learning tools for this emerging model system.Copyright © 2023 The Authors. Limnology and Oceanography: Methods published by Wiley Periodicals LLC on behalf of Association for the Sciences of Limnology and Oceanography. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. The linked file is the published version of the article.NHM Repositor