• Habitat Configuration Alters Herbivory across the Tropical Seascape

      Swindells, KL; Murdoch, RJ; Bazen, WD; Harman, NW; Unsworth, RKF (Frontiers, 2017-02-28)
      There exists increasing evidence that top-down ecological processes such as herbivory are key in controlling marine ecosystems and their community structure. Herbivory has the potential to be altered by numerous environmental and ecological factors that operate at a variety of temporal and spatial scales, one such spatial factor is the influence of the marine landscape. We know little about how ecological processes such as herbivory change throughout the marine landscape and how the effects of these processes cascade. This is because most landscape scale studies observe species richness and abundance patterns. In terrestrial systems the landscape is well documented to influence ecological processes, but empirical evidence of this is limited in marine systems. In tropical seagrass meadows direct herbivory by parrotfish can be readily observed due to the clear hemispherical bite marks they leave on the seagrass. As with herbivory in other systems, this leaf consumption is thought to assist with leaf turnover, positively influencing leaf growth. Changes in its rate and extent are therefore likely to influence the characteristics of the plant. The faunal communities of seagrass meadows alter with respect to changes in the landscape, particularly with respect to connectivity to adjacent habitats. It might therefore be expected that a key ecological process such as herbivory will change with respect to habitat configuration and have cascading impacts upon the status of the seagrass. In the present study we examined indirect evidence of parrotfish grazing throughout the marine landscape and assessed this relative to plant condition. Seagrasses in locations of close proximity to mangroves were found to have double the amount of parrotfish grazing than sites away from mangroves. Evidence of herbivory was also found to be strongly and significantly negatively correlated to the abundance of plant attached epicover. The decreased epicover in the presence of elevated herbivory suggests increased leaf turnover. These results indicate that seagrass may have higher levels of ecosystem resilience in the presence of mangroves. Our research highlights how ecological processes can change throughout the marine landscape with cascade impacts on the resilience of the system.
    • Halioticida noduliformans infection in eggs of lobster ( Homarus gammarus ) reveals its generalist parasitic strategy in marine invertebrates

      Holt, C; Foster, R; Daniels, CL; van der Giezen, M; Feist, SW; Stentiford, GD; Bass, D (2018-05)
    • Halloween genes in panarthropods and the evolution of the early moulting pathway in Ecdysozoa

      Schumann, I; Kenny, NJ; Hui, J; Hering, L; Meyer, G (The Royal Society, 2018-09-12)
      Moulting is a characteristic feature of Ecdysozoa—the clade of moulting animals that includes the hyperdiverse arthropods and less speciose groups, such as onychophorans, tardigrades and nematodes. Moulting has been best analysed in arthropods, specifically in insects and crustaceans, in which a complex neuroendocrine system acts at the genomic level and initiates the transcription of genes responsible for moulting. The key moulting hormones, ecdysone and 20-hydroxyecdysone, are subsequently synthesized from cholesterol ingested with food. Their biosynthesis is regulated by the Rieske-domain protein Neverland and cytochrome P450 enzymes encoded by the so-called ‘Halloween’ genes. Ecdysone is then released into the haemolymph and modified into 20-hydroxyecdysone, which binds to the nuclear receptor EcR/USP and initiates transcription of the Early genes. As little is known about the moulting pathway of other ecdysozoans, we examined the occurrence of genes involved in ecdysteroid biosynthesis and the early moulting cascade across ecdysozoan subgroups. Genomic and transcriptomic searches revealed no Halloween genes in cycloneuralians, whereas only shadow (CYP315A1) is present in onychophorans and tardigrades, suggesting that the Halloween genes evolved stepwise in panarthropods. These findings imply that the genes which were responsible for the ecdysteroid biosynthesis in the last common ancestor of Ecdysozoa are currently unknown.
    • Hansblockite, (Cu,Hg)(Bi,Pb)Se2, the monoclinic polymorph of grundmannite: a new mineral from the Se mineralization at El Dragón (Bolivia)

      Foerster, HJ; Bindi, L; Stanley, Christopher; Grundmann, G (Cambridge University Press, 2017-06)
      Hansblockite, ideally (Cu,Hg)(Bi,Pb)Se2, is a new selenide from the El Dragón mine, Bolivia. It typically occurs in thin subparallel plates intergrown with two unnamed Cu–Hg–Pb–Bi–Se species, clausthalite, Corich penroseite and petrovicite.It also forms subhedral to anhedral grains up to 150 μm long and 50 μm wide. Hansblockite is non-fluorescent, black and opaque with a metallic lustre and black streak. It is brittle, with an irregular fracture and no obvious parting and cleavage. The VHN20 values range from37 to 50 (mean 42) kg mm–2 (Mohs hardness 2–2½). In plane-polarized incident light, hansblockite is cream to light grey in colour, weakly bireflectant and weakly pleochroic from greyish cream to cream. Under crossed polars, hansblockite is weakly anisotropic withkhaki to pale blue rotation tints. The reflectance values in air for the Commission on Ore Mineralogy (COM) standard wavelengths are: 47.3–48.1 (470 nm), 47.4–49.9 (546 nm), 47.1–49.0 (589 nm) and 46.6–48.5 (650 nm). The mean composition is Cu 9.31, Ag 0.73, Hg 11.43,Pb 3.55, Ni 0.17, Co 0.03, Bi 31.17, Se 34.00, total 100.39 wt.%. The mean empirical formula (based on 4 apfu) is (Cu0.68Hg0.27Ag0.03Ni0.01)∑=0.99(Bi0.69Pb0.31)∑=1.00Se2.01. The simplifiedformula is (Cu,Hg) (Bi,Pb)Se2. Hansblockite is monoclinic, space group P21/c, with a = 6.853(1), b = 7.635(1), c = 7.264(1) Å, β = 97.68(1)°, V = 376.66(9) Å3 and Z = 4. Density is 8.26 gcm–3. The five strongest powder X-ray diffraction lines [d in Å (I/I 0) (hkl)] are: 3.97 (90) (111), 3.100 (40) (121), 2.986 (100) (211), 2.808 (50) (112) and 2.620 (50) (022). Hansblockite represents the monoclinic polymorph ofgrundmannite, CuBiSe2, with Hg and Pb being essential in stabilizing the monoclinic structure via the coupled substitution Cu+ + Bi3+⇔ Hg2+ + Pb2+. The mineral name is in honour of Hans Block (1881–1953), in recognition of hisimportant role in boosting Bolivian ore mining.
    • Has land use pushed terrestrial biodiversity beyond the planetary boundary? A global assessment

      Newbold, T; Hudson, L; Arnell, AP; Contu, S; De Palma, A; Ferrier, S; Hill, SLL; Hoskins, AJ; Lysenko, I; Phillips, HRP; et al. (2016-07-15)
    • Hemigrapsus takanoi Asakura and Watanabe, 2005 (Crustacea: Decapoda: Brachyura: Grapsoidea): first records of the brush-clawed shore crab from Great Britain

      Wood, C; Bishop, J; Davies, C; Delduca, E; Hatton, J; Herbert, R; Clark, P (Regional Euro-Asian Biological Invasions Centre, 2015-02-21)
      The brush-clawed shore crab is reported from the River Medway, Kent and the River Colne, Essex, England. These represent the first records of Hemigrapsus takanoi Asakura and Watanabe, 2005 from Great Britain. If H. takanoi becomes established in GB, it may pose a threat to populations of the native shore crab Carcinus maenas.
    • Herbivorous dinosaur jaw disparity and its relationship to extrinsic evolutionary drivers

      MacLaren, JA; Anderson, PSL; Barrett, PM; Rayfield, EJ (2017-02)
    • Heterochrony and parallel evolution of echinoderm, hemichordate and cephalochordate internal bars

      Álvarez-Armada, Nidia; Cameron, Christopher B; Bauer, Jennifer E; Rahman, Imran (The Royal Society, 2022-05-11)
      Deuterostomes comprise three phyla with radically different body plans. Phylogenetic bracketing of the living deuterostome clades suggests the latest common ancestor of echinoderms, hemichordates and chordates was a bilaterally symmetrical worm with pharyngeal openings, with these characters lost in echinoderms. Early fossil echinoderms with pharyngeal openings have been described, but their interpretation is highly controversial. Here, we critically evaluate the evidence for pharyngeal structures (gill bars) in the extinct stylophoran echinoderms Lagynocystis pyramidalis and Jaekelocarpus oklahomensis using virtual models based on high-resolution X-ray tomography scans of three-dimensionally preserved fossil specimens. Multivariate analyses of the size, spacing and arrangement of the internal bars in these fossils indicate they are substantially more similar to gill bars in modern enteropneust hemichordates and cephalochordates than to other internal bar-like structures in fossil blastozoan echinoderms. The close similarity between the internal bars of the stylophorans L. pyramidalis and J. oklahomensis and the gill bars of extant chordates and hemichordates is strong evidence for their homology. Differences between these internal bars and bar-like elements of the respiratory systems in blastozoans suggest these structures might have arisen through parallel evolution across deuterostomes, perhaps underpinned by a common developmental genetic mechanism.
    • Hidden Phylogenomic Signal Helps Elucidate Arsenurine Silkmoth Phylogeny and the Evolution of Body Size and Wing Shape Trade-Offs

      Hamilton, Chris A; Winiger, Nathalie; Rubin, Juliette J; Breinholt, Jesse; ROUGERIE, Rodolphe; Kitching, I; Barber, Jesse R; Kawahara, Akito Y (Oxford University Press (OUP), 2021-11-13)
      One of the key objectives in biological research is understanding how evolutionary processes have produced Earth’s diversity. A critical step toward revealing these processes is an investigation of evolutionary tradeoffs—that is, the opposing pressures of multiple selective forces. For millennia, nocturnal moths have had to balance successful flight, as they search for mates or host plants, with evading bat predators. However, the potential for evolutionary trade-offs between wing shape and body size are poorly understood. In this study, we used phylogenomics and geometric morphometrics to examine the evolution of wing shape in the wild silkmoth subfamily Arsenurinae (Saturniidae) and evaluate potential evolutionary relationships between body size and wing shape. The phylogeny was inferred based on 782 loci from target capture data of 42 arsenurine species representing all 10 recognized genera. After detecting in our data one of the most vexing problems in phylogenetic inference—a region of a tree that possesses short branches and no “support” for relationships (i.e., a polytomy), we looked for hidden phylogenomic signal (i.e., inspecting differing phylogenetic inferences, alternative support values, quartets, and phylogenetic networks) to better illuminate the most probable generic relationships within the subfamily. We found there are putative evolutionary trade-offs between wing shape, body size, and the interaction of fore- and hindwing (HW) shape. Namely, body size tends to decrease with increasing HW length but increases as forewing (FW) shape becomes more complex. Additionally, the type of HW (i.e., tail or no tail) a lineage possesses has a significant effect on the complexity of FW shape. We outline possible selective forces driving the complex HW shapes that make Arsenurinae, and silkmoths as a whole, so charismatic. [Anchored hybrid enrichment; Arsenurinae; geometric morphometrics; Lepidoptera; phylogenomics; Saturniidae.]
    • High-Density Cultivation of the Marine Ciliate Uronema marinum (Ciliophora, Oligohymenophorea) in Axenic Medium

      Zheng, W; Gao, F; Warren, A (2015-10-22)
      Uronema marinum is a cosmopolitan marine ciliate. It is a facultative parasite and the main causative agent of outbreaks of scuticociliatosis in aquaculture fish. This study reports a method for the axenic cultivation of U. marinum in high densities in an artificial medium comprising proteose peptone, glucose and yeast extract powder as its basic components. The absence of bacteria in the cultures was confirmed by fluorescence microscopy of DAPI-stained samples and the failure to recover bacterial SSU-rDNA using standard PCR methods. Using this axenic medium, a maximum cell density of 420,000 ciliate cells/ml was achieved, which is significantly higher than in cultures using living bacteria as food or in other axenic media reported previously. This method for high-density axenic cultivation of U. marinum should facilitate future research on this economically important facultative fish parasite.
    • 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.
    • Historic DNA for taxonomy and conservation: A case-study of a century-old Hawaiian hawkmoth type (Lepidoptera: Sphingidae)

      Hundsdoerfer, Anna K; Kitching, I (Public Library of Science (PLoS), 2017-03-08)
      Analysing historic DNA from museum specimens offers the unique opportunity to study the molecular systematics and phylogenetics of rare and possibly extinct taxa. In the Hawaiian fauna, the hawkmoth, Hyles calida calida, occurs on several of the main islands and is quite frequent, whereas Hyles c. hawaiiensis is restricted to the Island of Hawaii where it appears to be very rare. Analysis of mitochondrial DNA sequences shows that Hyles c. hawaiiensis differs from the nominotypical subspecies by an average p-distance of 2.8%, which is of a similar order of magnitude to that found between other species of Hyles, suggesting that Hyles c. hawaiiensis should perhaps be awarded species status, although more data are required for a formal taxonomic revision. Given the rarity of this taxon, these analyses should be undertaken urgently so that conservation measures can be implemented before it becomes extinct.
    • The history and morphology of Lord Howe Gallinule or Swamphen Porphyrio albus (Rallidae)

      van Grouw, Hein; Hume, JP (2016-09-01)
      The extinct Lord Howe Gallinule or Swamphen Porphyrio albus (White, 1790) is known from a number of written accounts, from at least ten contemporary paintings and from two skins, but the provenance of the specimens is confused and the taxonomic literature riddled with error. We present a review of the evidence and its reliability, demonstrate that the two extant specimens were collected on Lord Howe Island, provide details about when they were taken and by whom, and how they subsequently arrived in England. We further present evidence to demonstrate that Lord Howe Gallinule possessed several unique morphological characters.
    • History of the discovery of the mode of transmission of yellow fever virus

      Clements, AN; Harbach, RE (Wiley, 2017-11-10)
      This essay documents and examines the historical circumstances and events surrounding the discovery of the mode of transmission of yellow fever virus in Cuba. Close scrutiny of the articles published by Walter Reed and his colleagues in 1900, 1901 and 1902 reveals their limitations as historic documents. Fortunately, other sources of information from that period survive in letters and documents written by individuals involved in the quest for the mode of transmission. Examination and comparison of those sources of information unveiled a fascinating story which reveals that misunderstandings engendered by published articles accorded merit where it was not fully due.
    • Hominin Footprints from Early Pleistocene Deposits at Happisburgh, UK

      Ashton, N; Lewis, SG; De Groote, I; Duffy, SM; Bates, M; Bates, R; Hoare, P; Lewis, M; Parfitt, SA; Peglar, S; et al. (2014-02-07)
    • Honeaite, a new gold-thallium-telluride from the Eastern Goldfields, Yilgarn Craton, Western Australia

      Rice, CM; Welch, MD; Still, JW; Criddle, AJ; Stanley, Christopher (2016-01-24)
      Honeaite, ideal formula Au3TlTe2, is a new mineral from the late Archaean Karonie gold deposit, Eastern Goldfields province, Western Australia. Honeaite is found with native gold, tellurobismuthite, petzite, hessite, calaverite, melonite, mattagamite, frohbergite, altaite, pyrrhotite and molybdenite. These minerals are concentrated in microvughs and microfractures mainly within areas of prehnite alteration of amphibolite. The mineralisation appears to have been deposited under greenschistfacies conditions at lower temperatures than most gold deposits in the Eastern Goldfields. Single-crystal X-ray studies identified the structure of honeaite as orthorhombic, space group Pbcm, and unit cell parameters a = 8.9671(4) Å, b = 8.8758(4) Å, c = 7.8419(5) Å, V = 624.14(6) Å3 (Z = 4). The strongest reflections of the calculated powder X-ray diffraction pattern are [d in Å (I rel)(hkl)]: 2.938(100)(022), 2.905 (39,8)(322, 411), 2.989 (31)(300), 2.833 (23)(310), 1.853 (17)(332). Electron-microprobe analysis (EDS mode) gave (wt%) Au 56.33, Tl 19.68, Te 24.30, total 100.31, leading to an empirical formula (based on 2 Te apfu) of Au3.00Tl1.01Te2.00. Honeaite is black with a metallic lustre and no observed cleavage. The calculated density is 11.18 g/cm3. In reflected plane-polarized light it is slightly bluish grey. Between crossed polars it is weakly anisotropic with dark brown to dark blue rotation tints. Reflectance values in air and in oil are given. Honeaite is named after the late Russell M. Honea (1929–2002).