Now showing items 21-40 of 936

    • Using natural history collections to investigate changes in pangolin (Pholidota: Manidae) geographic ranges through time

      Buckingham, Emily; Curry, Jake; Emogor, Charles; Tomsett, Louise; Cooper, N (PeerJ, 2021-02-11)
      Pangolins, often considered the world’s most trafficked wild mammals, have continued to experience rapid declines across Asia and Africa. All eight species are classed as either Vulnerable, Endangered or Critically Endangered by the International Union for Conservation of Nature (IUCN) Red List. Alongside habitat loss, they are threatened mainly by poaching and/or legal hunting to meet the growing consumer demand for their meat and keratinous scales. Species threat assessments heavily rely on changes in species distributions which are usually expensive and difficult to monitor, especially for rare and cryptic species like pangolins. Furthermore, recent assessments of the threats to pangolins focus on characterising their trade using seizure data which provide limited insights into the true extent of global pangolin declines. As the consequences of habitat modifications and poaching/hunting on species continues to become apparent, it is crucial that we frequently update our understanding of how species distributions change through time to allow effective identification of geographic regions that are in need of urgent conservation actions. Here we show how georeferencing pangolin specimens from natural history collections can reveal how their distributions are changing over time, by comparing overlap between specimen localities and current area of habitat maps derived from IUCN range maps. We found significant correlations in percentage area overlap between species, continent, IUCN Red List status and collection year, but not ecology (terrestrial or arboreal/semi-arboreal). Human population density (widely considered to be an indication of trafficking pressure) and changes in primary forest cover, were weakly correlated with percentage overlap. Our results do not suggest a single mechanism for differences among historical distributions and present-day ranges, but rather show that multiple explanatory factors must be considered when researching pangolin population declines as variations among species influence range fluctuations. We also demonstrate how natural history collections can provide temporal information on distributions and discuss the limitations of collecting and using historical data.
    • Dinosaur diversification rates were not in decline prior to the K-Pg boundary

      Bonsor, Joseph; Barrett, PM; Raven, Tom; Cooper, N (The Royal Society, 2020-11-18)
      Determining the tempo and mode of non-avian dinosaur extinction is one of the most contentious issues in palaeobiology. Extensive disagreements remain over whether their extinction was catastrophic and geologically instantaneous or the culmination of long-term evolutionary trends. These conflicts have arisen due to numerous hierarchical sampling biases in the fossil record and differences in analytical methodology, with some studies identifying long-term declines in dinosaur richness prior to the Cretaceous–Palaeogene (K-Pg) boundary and others proposing continued diversification. Here, we use Bayesian phylogenetic generalized linear mixed models to assess the fit of 12 dinosaur phylogenies to three speciation models (null, slowdown to asymptote, downturn). We do not find strong support for the downturn model in our analyses, which suggests that dinosaur speciation rates were not in terminal decline prior to the K-Pg boundary and that the clade was still capable of generating new taxa. Nevertheless, we advocate caution in interpreting the results of such models, as they may not accurately reflect the complexities of the underlying data. Indeed, current phylogenetic methods may not provide the best test for hypotheses of dinosaur extinction; the collection of more dinosaur occurrence data will be essential to test these ideas further.
    • Novel Virus Discovery and Genome Reconstruction from Field RNA Samples Reveals Highly Divergent Viruses in Dipteran Hosts

      Cook, Shelley; Chung, Betty Y-W; Bass, David; Moureau, Gregory; Tang, Shuoya; McAlister, Erica; Culverwell, CL; Glücksman, Edvard; Wang, Hui; Brown, T David K; et al. (Public Library of Science (PLoS), 2013-11-18)
      We investigated whether small RNA (sRNA) sequenced from field-collected mosquitoes and chironomids (Diptera) can be used as a proxy signature of viral prevalence within a range of species and viral groups, using sRNAs sequenced from wild-caught specimens, to inform total RNA deep sequencing of samples of particular interest. Using this strategy, we sequenced from adult Anopheles maculipennis s.l. mosquitoes the apparently nearly complete genome of one previously undescribed virus related to chronic bee paralysis virus, and, from a pool of Ochlerotatus caspius and Oc. detritus mosquitoes, a nearly complete entomobirnavirus genome. We also reconstructed long sequences (1503-6557 nt) related to at least nine other viruses. Crucially, several of the sequences detected were reconstructed from host organisms highly divergent from those in which related viruses have been previously isolated or discovered. It is clear that viral transmission and maintenance cycles in nature are likely to be significantly more complex and taxonomically diverse than previously expected.
    • Aquatic Habits and Niche Partitioning in the Extraordinarily Long-Necked Triassic Reptile Tanystropheus

      Spiekman, Stephan NF; Neenan, James M; Fraser, Nicholas C; Fernandez, Vincent; Rieppel, Olivier; Nosotti, Stefania; Scheyer, Torsten M (Elsevier BV, 2020-08-06)
      Tanystropheus longobardicus is one of the most remarkable and iconic Triassic reptiles. Mainly known from the Middle Triassic conservation Lagerstätte of Monte San Giorgio on the Swiss-Italian border, it is characterized by an extraordinarily long and stiffened neck that is almost three times the length of the trunk, despite being composed of only 13 hyper-elongate cervical vertebrae [1-8]. Its paleobiology remains contentious, with both aquatic and terrestrial lifestyles having been proposed [1, 9-12]. Among the Tanystropheus specimens, a small morphotype bearing tricuspid teeth and a large morphotype bearing single-cusped teeth can be recognized, historically considered as juveniles and adults of the same species [4]. Using high-resolution synchrotron radiation microtomography (SRμCT), we three-dimensionally reconstruct a virtually complete but disarticulated skull of the large morphotype, including its endocast and inner ear, to reveal its morphology for the first time. The skull is specialized toward hunting in an aquatic environment, indicated by the placement of the nares on the top of the snout and a "fish-trap"-type dentition. The SRμCT data and limb bone paleohistology reveal that the large morphotype represents a separate species (Tanystropheus hydroides sp. nov.). Skeletochronology of the small morphotype specimens indicates that they are skeletally mature despite their small size, thus representing adult individuals of Tanystropheus longobardicus. The co-occurrence of these two species of disparate size ranges and dentitions provides strong evidence for niche partitioning, highlighting the surprising versatility of the Tanystropheus bauplan and the complexity of Middle Triassic nearshore ecosystems.
    • Cranial morphology of the tanystropheid Macrocnemus bassanii unveiled using synchrotron microtomography

      Miedema, Feiko; Spiekman, Stephan NF; Fernandez, Vincent; Reumer, Jelle WF; Scheyer, Torsten M (Springer Science and Business Media LLC, 2020-07-24)
      The genus Macrocnemus is a member of the Tanystropheidae, a clade of non-archosauriform archosauromorphs well known for their very characteristic, elongated cervical vertebrae. Articulated specimens are known from the Middle Triassic of Alpine Europe and China. Although multiple articulated specimens are known, description of the cranial morphology has proven challenging due to the crushed preservation of the specimens. Here we use synchrotron micro computed tomography to analyse the cranial morphology of a specimen of the type species Macrocnemus bassanii from the Besano Formation of Monte San Giorgio, Ticino, Switzerland. The skull is virtually complete and we identify and describe the braincase and palatal elements as well the atlas-axis complex for the first time. Moreover, we add to the knowledge of the morphology of the skull roof, rostrum and hemimandible, and reconstruct the cranium of M. bassanii in 3D using the rendered models of the elements. The circumorbital bones were found to be similar in morphology to those of the archosauromorphs Prolacerta broomi and Protorosaurus speneri. In addition, we confirm the palatine, vomer and pterygoid to be tooth-bearing palatal bones, but also observed heterodonty on the pterygoid and the palatine.
    • The cranial morphology of Tanystropheus hydroides (Tanystropheidae, Archosauromorpha) as revealed by synchrotron microtomography

      Spiekman, Stephan NF; Neenan, James M; Fraser, Nicholas C; Fernandez, Vincent; Rieppel, Olivier; Nosotti, Stefania; Scheyer, Torsten M (PeerJ, 2020-11-20)
      The postcranial morphology of the extremely long-necked Tanystropheus hydroides is well-known, but observations of skull morphology were previously limited due to compression of the known specimens. Here we provide a detailed description of the skull of PIMUZ T 2790, including a partial endocast and endosseous labyrinth, based on synchrotron microtomographic data, and compare its morphology to that of other early Archosauromorpha. In many features, such as the wide and flattened snout and the configuration of the temporal and palatal regions, Tanystropheus hydroides differs strongly from other early archosauromorphs. The braincase possesses a combination of derived archosaur traits, such as the presence of a laterosphenoid and the ossification of the lateral wall of the braincase, but also differs from archosauriforms in the morphology of the ventral ramus of the opisthotic, the horizontal orientation of the parabasisphenoid, and the absence of a clearly defined crista prootica. Tanystropheus hydroides was a ram-feeder that likely caught its prey through a laterally directed snapping bite. Although the cranial morphology of other archosauromorph lineages is relatively well-represented, the skulls of most tanystropheid taxa remain poorly understood due to compressed and often fragmentary specimens. The recent descriptions of the skulls of Macrocnemus bassanii and now Tanystropheus hydroides reveal a large cranial disparity in the clade, reflecting wide ecological diversity, and highlighting the importance of non-archosauriform Archosauromorpha to both terrestrial and aquatic ecosystems during the Triassic.
    • Unusual coloration of a Hairy woodpecker from Oregon

      Helm, SR; Stemmer, R; van Grouw, Hein (Society for Northwestern Vertebrate Biology, 2011-03-01)
    • A review of records of Downey Woodpecker in Britain

      van Grouw, Hein; Prys-Jones, Robert; Schofield, Philip (British Birds Ltd, 2020-04-15)
      Two historical records of Downy Woodpecker Dryobates pubescens in Britain are described. These records have not been formally reassessed for more than a century. A review of the records based on the available evidence is presented, which concludes that there is no support for Downy Woodpecker having occurred naturally in Britain.
    • White feathers in black birds

      van Grouw, Hein (British Birds Ltd, 2018-05-01)
      The most common plumage abnormalities in birds involve some form of white feathering, ranging from birds with just a few white feathers to individuals that are completely white. The causes of aberrant white feathers are diverse and, in many cases, unknown. Some are heritable, based on simple, genetically determined changes in the pigmentation process. More commonly, the causes are less clear-cut and can include environmental conditions (particularly in relation to food availability), and the physical condition and/or age of the bird. In this paper, white feathering is explored in three common species: Carrion Crow Corvus corone, Hooded Crow C. cornix and Blackbird Turdus merula. Results from the BTO Abnormal Plumage Survey are summarised, and data from a museum-based study of Blackbirds with plumage abnormalities are reported. In all three species, partly white plumage is recorded regularly and is often referred to incorrectly as albinism or leucism.
    • Clarifying collection details of specimens from Champion Bay, Western Australia, held in the Natural History Museum, Tring

      van Grouw, Hein; Horton, Philippa; Johnstone, JE (British Ornithologists' Club, 2016-06-06)
      Six bird specimens from Champion Bay (now Geraldton), Western Australia, were purchased by the British Museum from the dealer E. T. Higgins and registered in 1867. They included the first known specimen of Painted Finch Emblema pictum to have been collected after the holotype. All six specimens are of interest because their species are either rare or otherwise unknown in the Geraldton area. Widespread drought in the 1860s probably contributed to at least some of the unusual occurrences but cannot explain them all. Possible alternative locations for the specimens’ origins are investigated. Biographical details of the probable collectors of the specimens, A. H. du Boulay and F. H. du Boulay, are explored.
    • The second and third documented records of Antarctic Tern Sterna vittata in Brazil

      Carlos, Caio J; Daudt, Nicholas W; van Grouw, Hein; Neves, Tatiana (British Ornithologists' Club, 2017-12-11)
    • The Natural History Museum Fossil Porifera Collection

      Sendino, Consuelo (SAGE Publications, 2020-12-02)
      This article provides updated information about the Porifera Collection at The Natural History Museum (NHM), London. With very little information available regarding fossil sponge digitization or any similar initiative, this paper covers the type and figured specimens and drawer label content data of the Porifera Collection and also describes the collection and its research potential. With approximately 71,000 specimens, of which more than 60% are Mesozoic, the NHM holdings offer the best Mesozoic sponge collection in the world and one of the most important due to its breadth and depth. The Porifera Collection covers all stratigraphic periods and all taxonomic groups and includes almost 3000 cited and figured specimens including types. Although most of the specimens come from the British Isles, worldwide samples are also present, with abundant specimens from other Commonwealth countries and from Antarctica.
    • Temminck's Gallus giganteus; a gigantic obstacle to Darwin's theory of domesticated fowl origin?

      van Grouw, Hein; Dekkers, Wim (British Ornithologists' Club, 2020-09-21)
      In 1813, based on the single foot of a large chicken, Temminck named a ‘new' species of junglefowl, Gallus giganteus. He considered this ‘species’ the ancestor of several large domesticated chicken breeds and believed it was one of six wild ancestral species of domestic fowl. Temminck's hypothesis was rejected by Blyth who thought Red Junglefowl G. gallus was the sole ancestor. The arrival into Britain of several very large Asian chicken breeds in the mid-19th century led to speculation that Temminck's G. giganteus may have been their wild ancestor. Darwin, who had initially agreed with Blyth, noted several peculiarities in the Cochin, a large Asian breed, which he concluded might not have been achieved by selective breeding, and questioned whether G. giganteus was involved in their ancestry. Temminck's giant junglefowl appeared to be a significant hurdle for Darwin in his effort to prove a single ancestral origin for domestic chickens.
    • Streptopelia risoria and how Linnaeus had the last laugh

      van Grouw, Hein (British Ornithologists' Club, 2018-03-22)
      The dove known as Streptopelia risoria (Linnaeus, 1758) has long confused ornithologists. Linnaeus described a domestic variety of a dove whose wild form was then unknown. Its wild counterpart, African Collared Dove, was subsequently named Streptopelia roseogrisea (Sundevall, 1857) but that name’s type series was mixed. Despite this, the name roseogrisea became commonly accepted and was used for both African Collared Dove and its domestic form in avian taxonomy, whilst the name risoria was commonly used by bird-keepers for the domestic form. In 2008 the ICZN ruled that the senior name risoria should have priority for both African Collared Dove and its domestic form, Barbary Dove. Although this decision was appropriate, it was based on incomplete information. Here a detailed history of the use of the name risoria in the ornithological literature is presented, followed by designation of a neotype for roseogrisea to resolve taxonomy.
    • Female aristocrats in the natural history world before the establishment of the Geological Society of London

      Sendino, Consuelo; Porter, Julian (Geological Society of London, 2020-12-07)
      A fascination with natural history does not recognize class, as is shown through the activities of female aristocrats who, during the eighteenth and nineteenth centuries, contributed significantly by increasing the number of collections at natural history museums. These women were not members of the Geological Society of London because, at that time, women were not even allowed to be members, but they still left their impressive legacy in museums. This paper will focus on three women who made extensive collections that are now incorporated into British museums. The first of these, the Duchess of Portland, made one of the finest collections in England and, possibly, the best collection of shells and fossils in Europe of her time, which was later acquired by the Natural History Museum, London. She was followed by the Countess of Aylesford who made one of the most important mineral collections of her time, which is now at the Natural History Museum, London. Finally, Baroness Brassey collected geological samples during her trips that were used to establish the Brassey Institute in Hastings. These three women used their own income and influence to build collections.
    • Historic and modern genomes unveil a domestic introgression gradient in a wild red junglefowl population

      Wu, Meng Yue; Low, Gabriel Weijie; Forcina, Giovanni; van Grouw, Hein; Lee, Benjamin P Y‐H; Oh, Rachel Rui Ying; Rheindt, Frank E (Wiley, 2020-05-21)
      The red junglefowl Gallus gallus is the ancestor of the domestic chicken and arguably the most important bird species on Earth. Continual gene flow between domestic and wild populations has compromised its gene pool, especially since the last century when human encroachment and habitat loss would have led to increased contact opportunities. We present the first combined genomic and morphological admixture assessment of a native population of red junglefowl, sampled from recolonized parts of its former range in Singapore, partly using whole genomes resequenced from dozens of individuals. Crucially, this population was genomically anchored to museum samples from adjacent Peninsular Malaysia collected ~110–150 years ago to infer the magnitude of modern domestic introgression across individuals. We detected a strong feral–wild genomic continuum with varying levels of domestic introgression in different subpopulations across Singapore. Using a trait scoring scheme, we determined morphological thresholds that can be used by conservation managers to successfully identify individuals with low levels of domestic introgression, and selected traits that were particularly useful for predicting domesticity in genomic profiles. Our study underscores the utility of combined genomic and morphological approaches in population management and suggests a way forward to safeguard the allelic integrity of wild red junglefowl in perpetuity.
    • Calathus: A sample-return mission to Ceres

      Gassot, Oriane; Panicucci, Paolo; Acciarini, Giacomo; Bates, HC; Caballero, Manel; Cambianica, Pamela; Dziewiecki, Maciej; Dionnet, Zelia; Enengl, Florine; Gerig, Selina-Barbara; et al. (Elsevier BV, 2021-01-12)
      Ceres, as revealed by NASA's Dawn spacecraft, is an ancient, crater-saturated body dominated by low-albedo clays. Yet, localised sites display a bright, carbonate mineralogy that may be as young as 2 Myr. The largest of these bright regions (faculae) are found in the 92 km Occator Crater, and would have formed by the eruption of alkaline brines from a subsurface reservoir of fluids. The internal structure and surface chemistry suggest that Ceres is an extant host for a number of the known prerequisites for terrestrial biota, and as such, represents an accessible insight into a potentially habitable “ocean world”. In this paper, the case and the means for a return mission to Ceres are outlined, presenting the Calathus mission to return to Earth a sample of the Occator Crater faculae for high-precision laboratory analyses. Calathus consists of an orbiter and a lander with an ascent module: the orbiter is equipped with a high-resolution camera, a thermal imager, and a radar; the lander contains a sampling arm, a camera, and an on-board gas chromatograph mass spectrometer; and the ascent module contains vessels for four cerean samples, collectively amounting to a maximum 40 g. Upon return to Earth, the samples would be characterised via high-precision analyses to understand the salt and organic composition of the Occator faculae, and from there to assess both the habitability and the evolution of a relict ocean world from the dawn of the Solar System.
    • A new metriorhynchid crocodylomorph from the Oxford Clay Formation (Middle Jurassic) of England, with implications for the origin and diversification of Geosaurini

      Foffa, Davide; Young, Mark T; Brusatte, Stephen L; Graham, M; Steel, Lorna (Taylor and Francis, 2017-10-02)
      Metriorhynchids are an extinct group of Jurassic–Cretaceous crocodylomorphs secondarily adapted to a marine lifestyle. A new metriorhynchid crocodylomorph from the Oxford Clay Formation (Callovian, Middle Jurassic) of England is described. The specimen is a large, fragmentary skull and associated single ramus of a lower jaw uniquely preserved in a septarian concretion. The description of the specimen reveals a series of autapomorphies (apicobasal flutings on the middle labial surface of the tooth crowns, greatly enlarged basoccipital tuberosities) and a unique combination of characters that warrant the creation of a new genus and species: Ieldraan melkshamensis gen. et sp. nov. This taxon shares numerous characters with the Late Jurassic–Early Cretaceous genus Geosaurus: tooth crowns that have three apicobasal facets on their labial surface, subtly ornamented skull and lower jaws elements, and reception pits along the lateral margin of the dentary (maxillary overbite). Phylogenetic analysis places this new species as the sister taxon to Geosaurus. The new taxon adds valuable information on the time of origin of the macrophagous subclade Geosaurini, which was initially thought to have evolved and radiated during the Late Jurassic. The presence of Ieldraan melkshamensis, the phylogenetic re-evaluation of Suchodus durobrivensis as a Plesiosuchus sister taxon and recently identified Callovian Dakosaurus-like specimens in the Oxford Clay Formation, indicate that all major Geosaurini lineages originated earlier than previously supposed. This has major implications for the evolution of macropredation in the group. Specifically, we can now demonstrate that the four different forms of true ziphodonty observed in derived geosaurins independently evolved from a single non-functional microziphodont common ancestor.
    • An overlooked contributor to palaeontology—the preparator Richard Hall (b. 1839) and his work on an armoured dinosaur and a giant sea dragon

      Graham, M; Radley, Jonathan; Lomax, Dean; Brewer, Pip (Geological Curator, 2020-11-12)
      The work of Richard Hall, a fossil preparator at the British Museum (Natural History) in the late 19th century, has been largely unrecorded. It included the excavation, preparation and restoration of two important specimens: the dinosaur Polacanthus foxii and the ichthyosaur Temnodontosaurus platyodon. The painstaking reconstruction of the dorsal shield of Polacanthus took seven years to complete and enabled a supplemental note redescribing the specimen to be published in 1887. The significance of the discovery in 1898 of the Temnodontosaurus to the town of Stockton in Warwickshire was such that it featured in an article in Nature. It has entered the local folklore and remains celebrated on the town’s road signage and features as the logo of Stockton Primary School.