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Developing an integrated understanding of the evolution of arthropod segmentation using fossils and evo-devo
Get PDFSegmentation is fundamental to the arthropod body plan. Understanding the evolutionary steps by which arthropods became segmented is being transformed by the integration of data from evolutionary developmental biology (evo-devo), Cambrian fossils that allow the stepwise acquisition of segmental characters to be traced in the arthropod stem-group, and the incorporation of fossils into an increasingly well-supported phylogenetic framework for extant arthropods based on genomic-scale datasets. Both evo-devo and palaeontology make novel predictions about the evolution of segmentation that serve as testable hypotheses for the other, complementary data source. Fossils underpin such hypotheses as arthropodization originating in a frontal appendage and then being co-opted into other segments, and segmentation of the endodermal midgut in the arthropod stem-group. Insights from development, such as tagmatization being associated with different modes of segment generation in different body regions, and a distinct patterning of the anterior head segments, are complemented by palaeontological evidence for the pattern of tagmatization during ontogeny of exceptionally preserved fossils. Fossil and developmental data together provide evidence for a short head in stem-group arthropods and the mechanism of its formation and retention. Future breakthroughs are expected from identification of molecular signatures of developmental innovations within a phylogenetic framework, and from a focus on later developmental stages to identify the differentiation of repeated units of different systems within segmental precursors.Copyright © 2019 The Author(s). The attached file is the published version of the article.NHM Repositor
The genome sequence of the Whirlpool Ramshorn snail, Anisus vortex (Linnaeus, 1758)
Get PDFWe present a genome assembly from an individual Anisus vortex (the Whirlpool Ramshorn snail; Mollusca; Gastropoda; Hygrophila; Lymnaeoidea; Planorbidae). The genome sequence is 869.5 megabases in span. Most of the assembly is scaffolded into 18 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 13.57 kilobases in length.Copyright: © 2023 Skipp S et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted 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
Why Bolle's Laurel Pigeon Columba bollii is not named Wagler's Laurel Pigeon Columba lamprauchen
Get PDFThe Canary Islands endemic Bolle's Laurel Pigeon Columba bollii was described as a species in 1872 by Godman. A specimen of the same species collected more than 75 years earlier, during the 1796–98 expedition commanded by Baudin, was instead believed to be an example of the Jamaican endemic, Ring-tailed Pigeon Patagioenas caribaea (Jacquin, 1784). However, in 1827 its identity had been questioned by Wagler, who believed the specimen represented a separate Caribbean species that he named Columba Lamprauchen. Although Wagler's name is senior to Godman's, we demonstrate that, following the International code of zoological nomenclature, Columba bollii should be used as the correct name for this Canarian species.Copyright © 2024 The Authors; This is an open‐access article distributed under the terms of the Creative Commons Attribution-NonCommercial Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor
A crowd-sourced genomic project to assess hybrid content in a rare avian vagrant (Azure Tit Cyanistes cyanus (Pallas, 1770))
Get PDFThe aim of this study was to correlate plumage variation with the amount of genomic hybrid content in hybrids between Azure Tits Cyanistes cyanus (Pallas, 1770) and European Blue Tit Cyanistes caeruleus (Linnaeus, 1758), by re-sequencing the genomes of museum specimens of non-hybrids and presumed hybrids with varying plumages. The project was funded by crowdsourcing and initiated when two presumed Azure Tits, observed by hundreds of Swedish birdwatchers, were rejected as hybrids based on minor plumage deviations assumed to indicate hybrid contents from the European Blue Tit. The results confirm that hybrids with intermediate plumages, so called Pleske’s Tits, are first generation hybrids (F1 hybrids). Individuals, whose plumages are similar to Azure Tits, but assessed as hybrids based on minor plumage deviations, are all backcrosses but vary in their degree of hybrid
content. However, some individuals morphologically recognized as pure Azure Tits expressed similar degrees of hybrid content. The results indicate that: (1) hybrid content may be widespread in Azure Tits in the western part of its habitat distribution; (2) plumage deviation in backcrosses is not linearly correlated with the genetic degree of hybrid origin; and (3) all Azure Tits observed in Europe outside its natural distribution may have some degree of hybrid origin. We therefore suggest that it is very difficult to phenotypically single out hybrids beyond first generation backcrosses. We argue that decreased sequencing costs and improved analytical tools open the doors for museomic crowd-sourced projects that may not address outstanding biological questions but have a major interest for lay citizens such as birdwatchers.Copyright © 2023 The Authors. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). The attached file is the published version of the article.NHM Repositor
A deafening silence: a lack of data and reproducibility in published bioacoustics research?
Get PDFA study of 100 papers from five journals that make use of bioacoustic recordings shows that only a minority (21%) deposit any of the recordings in a repository, supplementary materials section or a personal website. This lack of deposition hinders re-use of the raw data by other researchers, prevents the reproduction of a project's analyses and confirmation of its findings and impedes progress within the broader bioacoustics community. We make some recommendations for researchers interested in depositing their data.Copyright © Baker E, Vincent S. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor
The oldest mineralized bryozoan? A possible palaeostomate in the lower Cambrian of Nevada, USA
Get PDFAll skeletal marine invertebrate phyla appeared during the Cambrian explosion, except for Bryozoa with mineralized skeletons, which first appear in the Early Ordovician. However, the skeletal diversity of Early Ordovician bryozoans suggests a preceding interval of diversification. We report a possible earliest occurrence of palaeostomate bryozoans in limestones of the Cambrian Age 4 Harkless Formation, western United States. Following recent interpretations of the early Cambrian Protomelission as a soft-bodied bryozoan, our findings add to the evidence of early Cambrian roots for the Bryozoa. The Harkless fossils resemble some esthonioporate and cystoporate bryozoans, showing a radiating pattern of densely packed tubes of the same diameter and cross-sectional shape. Further, they show partitioning of new individuals from parent tubes through the formation of a separate wall, a characteristic of interzooecial budding in bryozoans. If confirmed as bryozoans, these fossils would push back the appearance of mineralized skeletons in this phylum by ~30 million years and impact interpretations of their evolution.Copyright © 2022 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). https://creativecommons.org/licenses/by-nc/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. The attached file is the published version of the article.NHM Repositor
Bio+Mine Project: Empowering the Community to Develop a Site-Specific System for the Rehabilitation of a Legacy Mine
No full textThe rehabilitation of legacy mines continues to be a big challenge because of the difficulties in returning them to safe and stable conditions and ensuring that the mined-out areas become productive to support the economic activity of the host community. Previous efforts are often focused on purely technical and environmental aspects, leading to resistance from the local community due to their exclusion from the rehabilitation process. To address the issues associated with legacy mines and lack of participation of the community, we have developed a project, Biodiversity Positive Mining For The Net Zero Challenge (Bio + Mine), focusing on the abandoned Sto. Niño copper mine (Benguet, Philippines). The mine was closed in 1982 without a plan involving local stakeholders and leaving a significant ongoing negative legacy. Using the social-ecological-technological system framework, we will explore the intersections of the structure and functions of socio-economicdemographic, ecological, and technological data useful in devising a more inclusive mitigation strategy for the reconstruction of the supporting ecosystem. We aim to develop a site-specific system, underpinned by the local community's knowledge and practices, that can be a model for wider implementation in other legacy and active mines worldwide.Copyright © The Author(s) 2023. The linked file is the published version of the article.NHM Repositor
Nanopore adaptive sampling: a tool for enrichment of low abundance species in metagenomic samples
Get PDFAdaptive sampling is a method of software-controlled enrichment unique to nanopore sequencing platforms. To test its potential for enrichment of rarer species within metagenomic samples, we create a synthetic mock community and construct sequencing libraries with a range of mean read lengths. Enrichment is up to 13.87-fold for the least abundant species in the longest read length library; factoring in reduced yields from rejecting molecules the calculated efficiency raises this to 4.93-fold. Finally, we introduce a mathematical model of enrichment based on molecule length and relative abundance, whose predictions correlate strongly with mock and complex real-world microbial communities.Copyright © The Author(s). 2022 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. The attached file is the published version of the article.NHM Repositor
Cuticle ultrastructure of the Early Devonian trigonotarbid arachnid Palaeocharinus
Get PDFThe cuticle is a key evolutionary innovation that played a crucial role in arthropod terrestrialization. Extensive research has elucidated the chemical and structural composition of the cuticle in extant arthropods, while fossil studies have further informed our understanding of cuticle evolution. This study examines the three-dimensionally preserved cuticular structure of the Early Devonian trigonotarbid arachnid genus Palaeocharinus, from the Rhynie chert of Scotland (∼408 Ma). Trigonotarbids, an extinct group of tetrapulmonate arachnids, are among the earliest known unequivocally terrestrial arthropods, and thus may shed light on the evolution of terrestriality. Using high-resolution Confocal Laser Scanning Microscopy (CLSM), we reveal detailed morphological features at the nanometre level. The external cuticle surface of Palaeocharinus is characterized by polygonal scales, sensilla, and small pores identified as the openings of dermal glands and wax canals. Internally, the cuticle exhibits polygonal clusters of pore canals, through which wax was transported from the epidermis to the cuticular surface. The pore canals twist along their vertical axes, reflecting the "twisted plywood" or Bouligand arrangement of chitin-protein microfibril planes characteristic of modern arthropod cuticles. Overall, the cuticle of Palaeocharinus is characteristically thick relative to those of other extinct and extant chelicerates, such thickening being a possible adaptation to terrestrial life.Copyright © 2024 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). The attached file is the published version of the article.NHM Repositor
The Founding Feathers: the true ancestry of the domestic Barbary Dove
Get PDFIn 2008 the International Commission for Zoological Nomenclature (ICZN) ruled that the name Streptopelia risoria (Linnaeus, 1758) should have priority for both African Collared Dove and its domestic form, Barbary Dove, as it is senior to S. roseogrisea (Sundevall, 1857). Many ignored the ruling in the belief that the ancestry of Barbary Dove is still unproven. Given the lack of a namebearing specimen and in anticipation of the ICZN decision, in 2008 a neotype was designated for S. risoria. To clarify the taxonomic status of roseogrisea, as its original type series was mixed, in 2018 a neotype was also designated for this junior
synonym of African Collared Dove. As the species was assumed to be polytypic, synonymisation of roseogrisea with risoria at species level was questioned thereafter. The results of a whole genome-resequencing study now show that African Collared
Dove is the principal ancestor of Barbary Dove, and that the species is monotypic.Copyright © 2023 The Authors; This is an open‐access article distributed under the terms of the Creative Commons Attribution-NonCommercial Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. The attached file is the published version of the article.NHM Repositor