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  • Two new sympatric species of the pirate spider genus Ero C.L. Koch, 1836 from the cloud forest of Saint Helena Island, South Atlantic Ocean (Araneae: Mimetidae)

    Sherwood, Danniella; Henrard, Arnaud; Peters, Martina; Price, BW; Hall, Andie; White, Oliver W; Grignet, Virginie; Wilkins, Vicky (Museum National D'Histoire Naturelle, 2024-02-02)
    A remarkable morphologically and genetically distinct species of the genus Ero C.L. Koch, 1836 is described based on both sexes from the cloud forest of the island of Saint Helena: Ero lizae sp. nov. Another new species, Ero natashae sp. nov., is also described on the basis of morphological differences in the male and female genitalia. Both species were initially reported a single species, Ero aphana (Walckenaer, 1802), from the island by Unzicker (1977).
  • Unprecedented frequency of mitochondrial introns in colonial bilaterians

    Jenkins, Helen Louise; Graham, Rachael; Porter, Joanne Sara; Vieira, Leandro Manzoni; de Almeida, Ana Carolina Sousa; Hall, Andrea; O’Dea, Aaron; Coppard, Simon Edward; Waeschenbach, A (Springer Science and Business Media LLC, 2022-06-28)
    Abstract Animal mitogenomes are typically devoid of introns. Here, we report the largest number of mitochondrial introns ever recorded from bilaterian animals. Mitochondrial introns were identified for the first time from the phylum Bryozoa. They were found in four species from three families (Order Cheilostomatida). A total of eight introns were found in the complete mitogenome of Exechonella vieirai, and five, 17 and 18 introns were found in the partial mitogenomes of Parantropora penelope, Discoporella cookae and Cupuladria biporosa, respectively. Intron-encoded protein domains reverse transcriptase and intron maturase (RVT-IM) were identified in all species. Introns in E. vieirai and P. penelope had conserved Group II intron ribozyme domains V and VI. Conserved domains were lacking from introns in D. cookae and C. biporosa, preventing their further categorization. Putative origins of metazoan introns were explored in a phylogenetic context, using an up-to-date alignment of mitochondrial RVT-IM domains. Results confirmed previous findings of multiple origins of annelid, placozoan and sponge RVT-IM domains and provided evidence for common intron donor sources across metazoan phyla. Our results corroborate growing evidence that some metazoans with regenerative abilities (i.e. placozoans, sponges, annelids and bryozoans) are susceptible to intron integration, most likely via horizontal gene transfer.
  • Evaluation of genome skimming to detect and characterise human and livestock helminths

    PAPAIAKOVOU, MARINA; Fraija-Fernández, Natalia; James, Katherine; Briscoe, AG; Hall, Andie; Jenkins, Timothy P; Dunn, Julia; Levecke, Bruno; Mekonnen, Zeleke; Cools, Piet; et al. (Elsevier BV, 2023-01-11)
    The identification of gastrointestinal helminth infections of humans and livestock almost exclusively relies on the detection of eggs or larvae in faeces, followed by manual counting and morphological characterisation to differentiate species using microscopy-based techniques. However, molecular approaches based on the detection and quantification of parasite DNA are becoming more prevalent, increasing the sensitivity, specificity and throughput of diagnostic assays. High-throughput sequencing, from single PCR targets through to the analysis of whole genomes, offers significant promise towards providing information-rich data that may add value beyond traditional and conventional molecular approaches; however, thus far, its utility has not been fully explored to detect helminths in faecal samples. In this study, low-depth whole genome sequencing, i.e. genome skimming, has been applied to detect and characterise helminth diversity in a set of helminth-infected human and livestock faecal material. The strengths and limitations of this approach are evaluated using three methods to characterise and differentiate metagenomic sequencing data based on (i) mapping to whole mitochondrial genomes, (ii) whole genome assemblies, and (iii) a comprehensive internal transcribed spacer 2 (ITS2) database, together with validation using quantitative PCR (qPCR). Our analyses suggest that genome skimming can successfully identify most single and multi-species infections reported by qPCR and can provide sufficient coverage within some samples to resolve consensus mitochondrial genomes, thus facilitating phylogenetic analyses of selected genera, e.g. Ascaris spp. Key to this approach is both the availability and integrity of helminth reference genomes, some of which are currently contaminated with bacterial and host sequences. The success of genome skimming of faecal DNA is dependent on the availability of vouchered sequences of helminths spanning both taxonomic and geographic diversity, together with methods to detect or amplify minute quantities of parasite nucleic acids in mixed samples.
  • Reconstructing the feeding ecology of Cambrian sponge reefs: the case for active suspension feeding in Archaeocyatha

    Gibson, Brandt M; Chipman, Max; Attanasio, Paolo; Qureshi, Zaid; Darroch, Simon AF; Rahman, Imran A; Laflamme, Marc (The Royal Society, 2023-11-22)
    Sponge-grade Archaeocyatha were early Cambrian biomineralizing metazoans that constructed reefs globally. Despite decades of research, many facets of archaeocyath palaeobiology remain unclear, making it difficult to reconstruct the palaeoecology of Cambrian reef ecosystems. Of specific interest is how these organisms fed; previous experimental studies have suggested that archaeocyaths functioned as passive suspension feeders relying on ambient currents to transport nutrient-rich water into their central cavities. Here, we test this hypothesis using computational fluid dynamics (CFD) simulations of digital models of select archaeocyath species. Our results demonstrate that, given a range of plausible current velocities, there was very little fluid circulation through the skeleton, suggesting obligate passive suspension feeding was unlikely. Comparing our simulation data with exhalent velocities collected from extant sponges, we infer an active suspension feeding lifestyle for archaeocyaths. The combination of active suspension feeding and biomineralization in Archaeocyatha may have facilitated the creation of modern metazoan reef ecosystems. The attached file is the published version of the article.
  • A multi-taxon analysis of European Red Lists reveals major threats to biodiversity

    Hochkirch, Axel; Bilz, Melanie; Ferreira, Catarina C; Danielczak, Anja; Allen, David; Nieto, Ana; Rondinini, Carlo; Harding, Kate; Hilton-Taylor, Craig; Pollock, Caroline M; et al. (Public Library of Science (PLoS), 2023-11-08)
    Biodiversity loss is a major global challenge and minimizing extinction rates is the goal of several multilateral environmental agreements. Policy decisions require comprehensive, spatially explicit information on species’ distributions and threats. We present an analysis of the conservation status of 14,669 European terrestrial, freshwater and marine species (ca. 10% of the continental fauna and flora), including all vertebrates and selected groups of invertebrates and plants. Our results reveal that 19% of European species are threatened with extinction, with higher extinction risks for plants (27%) and invertebrates (24%) compared to vertebrates (18%). These numbers exceed recent IPBES (Intergovernmental Platform on Biodiversity and Ecosystem Services) assumptions of extinction risk. Changes in agricultural practices and associated habitat loss, overharvesting, pollution and development are major threats to biodiversity. Maintaining and restoring sustainable land and water use practices is crucial to minimize future biodiversity declines.
  • Forest leaf litter beetles of Taiwan: first DNA barcodes and first insight into the fauna

    Hu, Fang-Shuo; Arriaga-Varela, Emmanuel; Biffi, Gabriel; Bocák, Ladislav; Bulirsch, Petr; Damaška, Albert František; Frisch, Johannes; Hájek, Jiří; Hlaváč, Peter; Ho, Bin-Hong; et al. (Pensoft Publishers, 2024-01-08)
    We report the publication of 953 DNA barcodes of forest leaf litter beetles from central Taiwan, in total representing 334 species of 36 beetle families. This is the first bulk of data from the Taiwanese Leaf Litter beetles project focused on uncovering the under-explored diversity of leaf litter beetles across Taiwan. Based on these data, we provide the first records of the following taxa for Taiwan: family Sphindidae (genus Aspidiphorus Ziegler, 1821); tribes Trichonychini, Ctenistini, and Bythinoplectini (all Staphylinidae: Pselaphinae); genera Gyrelon Hinton, 1942, Thyroderus Sharp, 1885, Cautomus Sharp, 1885 (all Cerylonidae), Dermatohomoeus Hlisnikovský, 1963 (Leiodidae), Paraploderus Herman, 1970 (Staphylinidae: Oxytelinae), Thinocharis Kraatz, 1859 (Staphylinidae: Paederinae), Cephennodes Reitter, 1884, Napoconnus Franz, 1957 (both Staphylinidae: Scydmaeninae), Bicava Belon, 1884 (Latridiidae), Otibazo Morimoto, 1961, Seleuca Pascoe, 1871 and Acallinus Morimoto, 1962 (all Curculionidae); species Oodes (Lachnocrepis) japonicus (Bates, 1873) (Carabidae: Licininae), Drusilla obliqua (Bernhauer, 1916) (Staphylinidae: Aleocharinae) and Coccotrypes advena Blandford, 1894 (Curculionidae: Scolytinae). The records of Anapleus Horn, 1873 (Histeridae) and Batraxis Reitter, 1882 (Staphylinidae: Pselaphinae) have been confirmed. The male of Sivacrypticus taiwanicus Kaszab, 1964 (Archeocrypticidae) is described for the first time. Gyrelon jenpani Hu, Fikáček & Matsumoto, sp. nov. (Cerylonidae) is described, illustrated, and compared with related species. DNA barcodes associated larvae of 42 species with adults, we are concisely illustrating some of these: Oodes japonicus, Perigona cf. nigriceps Dejean, 1831 (both Carabidae), Ptilodactyla sp. (Ptilodactylidae), Maltypus ryukyuanus Wittmer, 1970 (Cantharidae), Drusilla obliqua, Myrmecocephalus brevisulcus (Pace, 2008), Diochus sp., Mimopinophilus sp. (all Staphylinidae), Stelidota multiguttata Reitter, 1877, Lasiodites inaequalis (Grouvelle, 1914) (both Nitidulidae), Lagria scutellaris Pic, 1910, and Anaedus spinicornis Kaszab, 1973 (both Tenebrionidae). We also report the first cases of Rickettsia infections in Scydmaeninae and Pselaphinae. All data (sequences, metadata, and voucher photos) are made public in BOLD database and in a Zenodo Archive.
  • Origin and Early Evolution of Echinoderms

    Rahman, Imran; Zamora, Samuel (Annual Reviews, 2024-05-30)
    Echinoderms are a major group (phylum) of invertebrate animals with a rich fossil record stretching back to the Cambrian period, approximately 518 million years ago. While all modern species are characterized by pentaradial (i.e., fivefold) symmetry, Cambrian echinoderms also include taxa with different types of symmetry (e.g., bilateral symmetry). These distinct forms were present from very early in the phylum's history, demonstrating that the initial diversification of echinoderm body plans was extremely rapid. The phylogenetic relationships of Cambrian echinoderms have long been debated, hindering efforts to reconstruct the evolution of the phylum, but recent analyses have consistently recovered bilaterally symmetrical forms as the earliest-diverging echinoderms. This reveals the sequence of character acquisition in echinoderm evolution, indicating that radial symmetry is a derived character of the group, which evolved after the acquisition of a mineralized skeleton. Cambrian echinoderms were adapted to diverse modes of life, with ecology an important factor shaping their early evolution. However, the reasons why echinoderms evolved their unique pentaradial body plan remain unclear. ▪ The Cambrian fossil record provides valuable insights into the origin and early evolution of echinoderms over half a billion years ago. ▪ Cambrian echinoderms were morphologically diverse, with several extinct groups exhibiting character combinations that distinguish them from living species. ▪ Phylogenetic analyses of bilateral, asymmetrical, triradial, and pentaradial fossils have allowed us to decipher the assembly of the modern echinoderm body plan. ▪ Echinoderms became ecologically diverse early in their history, with varied modes of feeding, locomotion, and attachment. Expected final online publication date for the Annual Review of Earth and Planetary Sciences, Volume 52 is May 2024. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
  • Diversity and Phylogeny of Novel Cord-Forming Fungi from Borneo

    Foster, R; Hartikainen, Hanna; Hall, Andie; Bass, David (MDPI AG, 2022-01-22)
    Cord-forming (CF) fungi are found worldwide; however, tropical CF fungi are poorly documented. They play an essential role in forest ecosystems by interconnecting nutrient resources and aiding in the decomposition of plant matter and woody litter. CF fungi samples were collected from two forest conservation sites in the Sabah region of Malaysian Borneo. Sequencing and phylogenetic analysis of the ribosomal rRNA gene array 18S to 28S region from cords collected placed all of the collected specimens in Agaricomycetes (Basidiomycetes), specifically within the orders Trechisporales, Phallales, Hymenochaetales, Polyporales, and Agaricales. Comparison of the cord-derived sequences against GenBank and UNITE sequence databases, as well as phylogenetic analyses, revealed they were all novel sequences types. Many of these novel lineages were found to be closely related to other basidiomycetes commonly found in tropical forests, suggesting a large undiscovered tropical fungal diversity in Borneo that has been detected independently of sampling fruiting bodies. We show how these sequence types relate to the morphologies of the cords from which they were sampled. We also highlight how rapid, small-scale sampling can be a useful tool as an easy and relatively unbiased way of collecting data on cord-forming fungi in difficult-to-access, complex forest environments, independently of locating and sampling sporophores.
  • Innovation in Citizen Science – Perspectives on Science-Policy Advances

    Hecker, Susanne; Bonney, Rick; Haklay, Muki; Hölker, Franz; Hofer, Heribert; Goebel, Claudia; Gold, Margaret; Makuch, Zen; Ponti, Marisa; Richter, Anett; et al. (Ubiquity Press, Ltd., 2018-04-27)
    Citizen science is growing as a field of research with contributions from diverse disciplines, promoting innovation in science, society, and policy. Inter- and transdisciplinary discussions and critical analyses are needed to use the current momentum to evaluate, demonstrate, and build on the advances that have been made in the past few years. This paper synthesizes results of discussions at the first international citizen science conference of the European Citizen Science Association (ECSA) in 2016 in Berlin, Germany, and distills major points of the discourse into key recommendations. To enhance innovation in science, citizen science needs to clearly demonstrate its scientific benefit, branch out across disciplines, and foster active networking and new formats of collaboration, including true co-design with participants. For fostering policy advances, it is important to embrace opportunities for policy-relevant monitoring and policy development and to work with science funders to find adequate avenues and evaluation tools to support citizen science. From a society angle it is crucial to engage with societal actors in various formats that suit participants and to evaluate two-way learning outcomes as well as to develop the transformative role of science communication. We hope that these key perspectives will promote citizen science progress at the science-society-policy interface.
  • Ten principles of citizen science

    Robinson, LD; Cawthray, Jade Lauren; West, Sarah Elizabeth; Bonn, Aletta; Ansine, Janice; Haklay, Muki; Hecker, Susanne; Bowser, Anne; Makuch, Zen; Vogel, Johannes; et al. (UCL Press, 2018-10-15)
    Citizen science, the active participation of the public in scientific research projects, is a rapidly expanding field in open science and open innovation. It provides an integrated model of public knowledge production and engagement with science. As a growing worldwide phenomenon, it is invigorated by evolving new technologies that connect people easily and effectively with the scientific community. Catalysed by citizens’ wishes to be actively involved in scientific processes, as a result of recent societal trends, it also offers contributions to the rise in tertiary education. In addition, citizen science provides a valuable tool for citizens to play a more active role in sustainable development. This book identifies and explains the role of citizen science within innovation in science and society, and as a vibrant and productive science-policy interface. The scope of this volume is global, geared towards identifying solutions and lessons to be applied across science, practice and policy. The chapters consider the role of citizen science in the context of the wider agenda of open science and open innovation, and discuss progress towards responsible research and innovation, two of the most critical aspects of science today.
  • How Do Young Community and Citizen Science Volunteers Support Scientific Research on Biodiversity? The Case of iNaturalist

    Aristeidou, Maria; Herodotou, Christothea; Ballard, Heidi L; Higgins, Lila; Johnson, Rebecca F; Miller, Annie E; Young, Alison N; Robinson, LD (MDPI AG, 2021-07-13)
    Online community and citizen science (CCS) projects have broadened access to scientific research and enabled different forms of participation in biodiversity research; however, little is known about whether and how such opportunities are taken up by young people (aged 5–19). Furthermore, when they do participate, there is little research on whether their online activity makes a tangible contribution to scientific research. We addressed these knowledge gaps using quantitative analytical approaches and visualisations to investigate 249 youths’ contributions to CCS on the iNaturalist platform, and the potential for the scientific use of their contributions. We found that nearly all the young volunteers’ observations were ‘verifiable’ (included a photo, location, and date/time) and therefore potentially useful to biodiversity research. Furthermore, more than half were designated as ‘Research Grade’, with a community agreed-upon identification, making them more valuable and accessible to biodiversity science researchers. Our findings show that young volunteers with lasting participation on the platform and those aged 16–19 years are more likely to have a higher proportion of Research Grade observations than younger, or more ephemeral participants. This study enhances our understanding of young volunteers’ contributions to biodiversity research, as well as the important role professional scientists and data users can play in helping verify youths’ contributions to make them more accessible for biodiversity research.
  • Understanding the Citizen Science Landscape for European Environmental Policy: An Assessment and Recommendations

    Turbé, Anne; Barba, Jorge; Pelacho, Maite; Mugdal, Shailendra; Robinson, LD; Serrano-Sanz, Fermin; Sanz, Francisco; Tsinaraki, Chrysa; Rubio, Jose-Miguel; Schade, Sven (Ubiquity Press, Ltd., 2019-12-02)
    Citizen science is increasingly upheld with the potential to underpin all aspects of the environmental policy process. However, to date, contributions of citizen science to environmental decision-making remain sparse and not well understood. Evidence points to a gap between the potential relevance of citizen science for policy and its actual implementation. We lack a comprehensive assessment of the current impacts of citizen science projects on environmental policy, and an identification of the scientific, engagement, and governance characteristics of projects that facilitate successful contributions to policy. This paper addresses that knowledge gap through identifying the characteristics of citizen science projects that support policy. We present an inventory of 503 citizen science projects with environmental policy relevance, and an in-depth analysis of 45 case examples with quantitative assessment of characteristics of the citizen scientist, scientific, socio-economic, and policy dimensions. Our results demonstrate that citizen science can underpin all steps of the environmental policy process, and that a diversity of approaches can be used to achieve this. However, governmental support, scientific excellence, and NGO-leadership facilitate policy linkages. We discuss the main challenges and opportunities identified by project leaders in linking citizen science and policy and present a set of recommendations for promoting the better integration of citizen science in the different phases of the policy cycle. Central among these are clarifying policy needs, facilitating access to citizen science data, and improving their evaluation and recognition by decision-makers.
  • The diversity and evolution of ecological and environmental citizen science

    Pocock, Michael JO; Tweddle, John C; Savage, Joanna; Robinson, LD; Roy, Helen E (Public Library of Science (PLoS), 2017-04-03)
    Citizen science—the involvement of volunteers in data collection, analysis and interpretation —simultaneously supports research and public engagement with science, and its profile is rapidly rising. Citizen science represents a diverse range of approaches, but until now this diversity has not been quantitatively explored. We conducted a systematic internet search and discovered 509 environmental and ecological citizen science projects. We scored each project for 32 attributes based on publicly obtainable information and used multiple factor analysis to summarise this variation to assess citizen science approaches. We found that projects varied according to their methodological approach from ‘mass participation’ (e.g. easy participation by anyone anywhere) to ‘systematic monitoring’ (e.g. trained volunteers repeatedly sampling at specific locations). They also varied in complexity from approaches that are ‘simple’ to those that are ‘elaborate’ (e.g. provide lots of support to gather rich, detailed datasets). There was a separate cluster of entirely computer-based projects but, in general, we found that the range of citizen science projects in ecology and the environment showed continuous variation and cannot be neatly categorised into distinct types of activity. While the diversity of projects begun in each time period (pre1990, 1990–99, 2000–09 and 2010–13) has not increased, we found that projects tended to have become increasingly different from each other as time progressed (possibly due to changing opportunities, including technological innovation). Most projects were still active so consequently we found that the overall diversity of active projects (available for participation) increased as time progressed. Overall, understanding the landscape of citizen science in ecology and the environment (and its change over time) is valuable because it informs the comparative evaluation of the ‘success’ of different citizen science approaches. Comparative evaluation provides an evidence-base to inform the future development of citizen science activities.
  • “No todo es Sargazo”: Aprendizajes en un proyecto de ciencia ciudadana marino-coster

    Benavides Lahnstein, Ana Ilse; Paredes Chi, Arely; Rios Vazquez, Ameyalli; Galindo-De Santiago, Maria del Carmen; Khatun, Kaysara; Vazquez Delfin, Erika; Robinson, LD; Brodie, J; Wardlaw, Jessica (Universitat Autònoma de Barcelona, 2023)
    Appendices
  • Unveiled: Prototrichalus from the mid-Cretaceous Burmese amber represents a yet oldest record of Ischaliidae Blair, 1920 (Coleoptera: Tenebrionoidea)

    Telnov, Dmitry; Kairišs, Kristaps; Triskova, Katerina; Kundrata, Robin (Elsevier BV, 2023-06-30)
    The genus Prototrichalus Molino-Olmedo, Ferreira, Branham and Ivie, 2020 known from Burmese amber was initially attributed to the family of net-winged beetles (Coleoptera: Lycidae) in the superfamily Elateroidea, and soon after transferred to Tenebrionoidea incertae sedis and compared with Ischalia Pascoe, 1860. Here, we examined additional material of Prototrichalus and confirmed it is the first known Mesozoic subgroup of the family of false fire-coloured beetles (Coleoptera: Ischaliidae) in superfamily Tenebrionoidea. This oldest yet available record of the Ischaliidae suggests their at least Cretaceous origin. A re-defined set of the diagnostic features is provided for the family Ischaliidae to incorporate the unique combination of morphological features of Prototrichalus. One new species, P. jingpo Telnov and Kundrata, sp. nov., is described and compared with its congeners. A key to supraspecific taxa of Ischaliidae and an annotated checklist of extinct species of the family are provided.
  • Changes in technology and imperfect detection of nest contents impedes reliable estimates of population trends in burrowing seabirds

    Lavers, Jennifer L; Hutton, Ian; Bond, AL (Elsevier BV, 2019-02-25)
    One of the most fundamental aspects of conservation biology is understanding trends in the abundance of species and populations. This influences conservation interventions, threat abatement, and management by implicitly or explicitly setting targets for favourable conservation states, such as an increasing or stable population. Burrow-nesting seabirds present many challenges for determining abundance reliably, which is further hampered by variability in the quality of previous surveys. We used burrow scopes to determine the population status of Flesh-footed Shearwaters (Ardenna carneipes) at their largest colony on Lord Howe Island, Australia, in 2018. We estimated a breeding population of 22,654 breeding pairs (95% CI: 8159–37,909). Comparing burrow scope models used in 2018 found more than half of burrow contents (20/36 burrows examined) were classified differently. If this detection probability is applied retroactively to surveys in 2002 and 2009, we estimate that the Flesh-footed Shearwater population on Lord Howe has decreased by up to 50% in the last decade, but uncertainty around previous surveys’ ability to reliably determine burrow contents means a direct comparison is not possible. The decline in burrow density between 2018 and previous years adds further evidence that the population may not be stable. Our results highlight a need for regular surveys to quantify detection probability so that as video technology advances, previous population estimates remain comparable. We urge caution when comparing population counts of burrowing seabirds using different technologies, to ensure comparisons are meaningful.
  • How woodcocks produce the most brilliant white plumage patches among the birds

    Dunning, Jamie; Patil, Anvay; D'Alba, Liliana; Bond, AL; Debruyn, Gerben; Dhinojwala, Ali; Shawkey, Matthew; Jenni, Lukas (The Royal Society, 2023-03-01)
    Until recently, and when compared with diurnal birds that use contrasting plumage patches and complex feather structures to convey visual information, communication in nocturnal and crepuscular species was considered to follow acoustic and chemical channels. However, many birds that are active in low-light environments have evolved intensely white plumage patches within otherwise inconspicuous plumages. We used spectrophotometry, electron microscopy, and optical modelling to explain the mechanisms producing bright white tail feather tips of the Eurasian woodcock Scolopax rusticola. Their diffuse reflectance was approximately 30% higher than any previously measured feather. This intense reflectance is the result of incoherent light scattering from a disordered nanostructure composed of keratin and air within the barb rami. In addition, the flattening, thickening and arrangement of those barbs create a Venetian-blind-like macrostructure that enhances the surface area for light reflection. We suggest that the woodcocks have evolved these bright white feather patches for long-range visual communication in dimly lit environments.
  • Betula mcallisteri sp. nov. (sect. Acuminatae, Betulaceae), a new diploid species overlooked in the wild and in cultivation, and its relation to the widespread B. luminifera

    Zhang, Huayu; Ding, Junyi; Holstein, Norbert; Wang, Nian (2023-05-23)
    Taxa are traditionally identified using morphological proxies for groups of evolutionarily isolated populations. These proxies are common characters deemed by taxonomists as significant. However, there is no general rule on which character or sets of characters are appropriate to circumscribe taxa, leading to discussions and uncertainty. Birch species are notoriously hard to identify due to strong morphological variability and factors such as hybridization and the existence of several ploidy levels. Here, we present evidence for an evolutionarily isolated line of birches from China that are not distinguishable by traditionally assumed taxon recognition proxies, such as fruit or leaf characters. We have discovered that some wild material in China and some cultivated in the Royal Botanic Gardens Edinburgh, formerly recognized as Betula luminifera, differ from other individuals by having a peeling bark and a lack of cambial fragrance. We use restriction site-associated DNA sequencing and flow cytometry to study the evolutionary status of the unidentified Betula samples to assess the extent of hybridization between the unidentified Betula samples and typical B. luminifera in natural populations. Molecular analyses show the unidentified Betula samples as a distinct lineage and reveal very little genetic admixture between the unidentified samples and B. luminifera. This may also be facilitated by the finding that B. luminifera is tetraploid, while the unidentified samples turned out to be diploid. We therefore conclude that the samples represent a yet unrecognized species, which is here described as Betula mcallisteri.
  • A global phylogeny of butterflies reveals their evolutionary history, ancestral hosts and biogeographic origins

    Kawahara, Akito Y; Storer, Caroline; Carvalho, Ana Paula S; Plotkin, David M; Condamine, Fabien L; Braga, Mariana P; Ellis, Emily A; St Laurent, Ryan A; Li, Xuankun; Barve, Vijay; et al. (Springer Science and Business Media LLC, 2023-05-15)
    Abstract: Butterflies are a diverse and charismatic insect group that are thought to have evolved with plants and dispersed throughout the world in response to key geological events. However, these hypotheses have not been extensively tested because a comprehensive phylogenetic framework and datasets for butterfly larval hosts and global distributions are lacking. We sequenced 391 genes from nearly 2,300 butterfly species, sampled from 90 countries and 28 specimen collections, to reconstruct a new phylogenomic tree of butterflies representing 92% of all genera. Our phylogeny has strong support for nearly all nodes and demonstrates that at least 36 butterfly tribes require reclassification. Divergence time analyses imply an origin ~100 million years ago for butterflies and indicate that all but one family were present before the K/Pg extinction event. We aggregated larval host datasets and global distribution records and found that butterflies are likely to have first fed on Fabaceae and originated in what is now the Americas. Soon after the Cretaceous Thermal Maximum, butterflies crossed Beringia and diversified in the Palaeotropics. Our results also reveal that most butterfly species are specialists that feed on only one larval host plant family. However, generalist butterflies that consume two or more plant families usually feed on closely related plants.
  • Cambrian stem-group ambulacrarians and the nature of the ancestral deuterostome

    Li, Yujing; Dunn, Frances S; Murdock, Duncan JE; Guo, Jin; Rahman, Imran; Cong, Peiyun (Elsevier BV, 10/05/2023)
    Deuterostomes are characterized by some of the most widely divergent body plans in the animal kingdom. These striking morphological differences have hindered efforts to predict ancestral characters, with the origin and earliest evolution of the group remaining ambiguous. Several iconic Cambrian fossils have been suggested to be early deuterostomes and hence could help elucidate ancestral character states. However, their phylogenetic relationships are controversial. Here, we describe new, exceptionally preserved specimens of the discoidal metazoan Rotadiscus grandis from the early Cambrian Chengjiang biota of China. These reveal a previously unknown double spiral structure, which we interpret as a chordate-like covering to a coelomopore, located adjacent to a horseshoe-shaped tentacle complex. The tentacles differ in key aspects from those seen in lophophorates and are instead more similar to the tentacular systems of extant pterobranchs and echinoderms. Thus, Rotadiscus exhibits a chimeric combination of ambulacrarian and chordate characters. Phylogenetic analyses recover Rotadiscus and closely related fossil taxa as stem ambulacrarians, filling a significant morphological gap in the deuterostome tree of life. These results allow us to reconstruct the ancestral body plans of major clades of deuterostomes, revealing that key traits of extant forms, such as a post-analregion, gillbars, and a U-shaped gut, evolved through convergence.

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