• 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.
    • 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.
    • 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.
    • 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.
    • A Horizon Scan of research priorities to inform policies aimed at reducing the harm of plastic pollution to biota

      Provencher, JF; Liboiron, M; Borrelle, SB; Bond, AL; Rochman, C; Lavers, JL; Avery-Gomm, S; Yamashita, R; Ryan, PG; Lusher, AL; et al. (Elsevier, 2020-09-01)
      Plastic pollution in the oceans is a priority environmental issue. The recent increase in research on the topic, coupled with growing public awareness, has catalyzed policymakers around the world to identify and implement solutions that minimize the harm caused by plastic pollution. To aid and coordinate these efforts, we surveyed experts with scientific experience identified through their peer-reviewed publications. We asked experts about the most pressing research questions relating to how biota interact with plastic pollution that in turn can inform policy decisions and research agendas to best contribute to understanding and reducing the harm of plastic pollution to biota. We used a modified Horizon Scan method that first used a subgroup of experts to generate 46 research questions on aquatic biota and plastics, and then conducted an online survey of researchers globally to prioritize questions in terms of their importance to inform policy development. One hundred and fifteen experts from 29 countries ranked research questions in six themes. The questions were ranked by urgency, indicating which research should be addressed immediately, which can be addressed later, and which are of limited relevance to inform action on plastics as an environmental pollutant. We found that questions relating to the following four themes were the most commonly top-ranked research priorities: (i) sources, circulation and distribution of plastics, (ii) type of harm from plastics, (iii) detection of ingested plastics and the associated problems, and (iv) related economies and policy to ingested plastics. While there are many research questions on the topic of impacts of plastic pollution on biota that could be funded and investigated, our results focus collective priorities in terms of research that experts believe will inform effective policy and on-the-ground conservation.
    • Horizon scanning for invasive alien species with the potential to threaten biodiversity in Great Britain

      Roy, HE; Peyton, J; Aldridge, DC; Bantock, T; Blackburn, TM; Britton, R; Clark, P; Cook, E; Dehnen-Schmutz, K; Dines, T; et al. (Wiley, 2014-05-19)
    • The hosts of Ophion luteus (Linnaeus) (Hymenoptera, Ichneumonidae, Ophioninae) in Europe

      Broad, G; Schnee, H; Shaw, MR (2015-11-30)
      A widespread European nocturnal ichneumonid, Ophion luteus, is shown to be a parasitoid of at least two species of noctuid moth, Agrotis exclamationis and A. segetum, probably most frequently a parasitoid of the former. The taxonomy, nomenclature and diagnostic features of this species are discussed. Possible explanations for a spring-flying generation, usually referred to as the ‘distans’ morph, are discussed.
    • How climatic variability is linked to the spatial distribution of range sizes: seasonality versus climate change velocity in sphingid moths

      Grünig, M; Beerli, N; Ballesteros-Mejia, L; Kitching, I; Beck, J (Wiley, 2017-07-04)
      Aim To map the spatial variation of range sizes within sphingid moths, and to test hypotheses on its environmental control. In particular, we investigate effects of climate change velocity since the Pleistocene and the mid‐Holocene, temperature and precipitation seasonality, topography, Pleistocene ice cover, and available land area. Location Old World and Australasia, excluding smaller islands. Methods We used fine‐grained range maps (based on expert‐edited distribution modelling) for all 972 sphingid moth species in the research region and calculated, at a grain size of 100 km, the median of range sizes of all species that co‐occur in a pixel. Climate, topography and Pleistocene ice cover data were taken from publicly available sources. We calculated climate change velocities (CCV) for the last 21 kyr as well as 6 kyr. We compared the effects of seasonality and CCV on median range sizes with spatially explicit models while accounting for effects of elevation range, glaciation history and available land area. Results Range sizes show a clear spatial pattern, with highest median values in deserts and arctic regions and lowest values in isolated tropical regions. Range sizes were only weakly related to absolute latitude (predicted by Rapoport's effect), but there was a strong north‐south pattern of range size decline. Temperature seasonality emerged as the strongest environmental correlate of median range size, in univariate as well as multivariate models, whereas effects of CCV were weak and unstable for both time periods. These results were robust to variations in the parameters in alternative analyses, among them multivariate CCV. Main conclusions Temperature seasonality is a strong correlate of spatial range size variation, while effects of longer‐term temperature change, as captured by CCV, received much weaker support.
    • How common is albinism really? Colour aberrations in Indian birds reviewed

      Van Grouw, H; Mahabal, A; Sharma, RM; Thakur, S (2016-09-01)
    • How has the environment shaped geographical patterns of insect body sizes? A test of hypotheses using sphingid moths.

      Beerli, N; Bärtschi, F; Kitching, IJ; Ballesteros-Mejia, L; Beck, J (Wiley, 2019-05-14)
      Aim: We mapped the geographical pattern of body sizes in sphingid moths and investigated latitudinal clines. We tested hypotheses concerning their possible environmental control, that is, effects of temperature (negative: temperature size rule or Bergmann's rule; positive: converse Bergmann rule), food availability, robustness to starvation during extreme weather and seasonality. Location: Old World and Australia/Pacific region. Methods: Body size data of 950 sphingid species were compiled and related to their distribution maps. Focusing on body length, we mapped the median and maximum size of all species occurring in 100 km grid cells. In a comparative approach, we tested the predictions from explanatory hypotheses by correlating species' size to the average environmental conditions encountered throughout their range, under univariate and multivariate models. We accounted for phylogeny by stepwise inclusion of phylogenetically informed taxonomic classifications into hierarchical random‐intercept mixed models. Results: Median body sizes showed a distinctive geographical pattern, with large species in the Middle East and the Asian tropics, and smaller species in temperate regions and the Afrotropics. Absolute latitude explained very little body size variation, but there was a latitudinal cline of maximum size. Species' median size was correlated with net primary productivity, supporting the food availability hypothesis, whereas support for other hypotheses was weak. Environmental correlations contributed much less (i.e. <10%) to explaining overall size variation than phylogeny (inclusion of which led to models explaining >70% of variability). Main conclusion: The intuitive impression of larger species in the tropics is shaped by larger size maxima. Median body sizes are only very weakly related to latitude. Most of the geographical variation in body size in sphingid moths is explained by their phylogenetic past. NPP and forest cover correlate positively with the body size, which supports the idea that food availability allowed the evolution of larger sizes.
    • How the temperate world was colonised by bindweeds: biogeography of the Convolvuleae (Convolvulaceae)

      Mitchell, TC; Williams, BRM; Wood, JRI; Harris, DJ; Scotland, RW; Carine, MA (2016-12)
    • Hybrid capture data unravel a rapid radiation of pimpliform parasitoid wasps (Hymenoptera: Ichneumonidae: Pimpliformes)

      Klopfstein, S; Langille, B; Spasojevic, T; Broad, G; Cooper, SJB; Austin, AD; Niehuis, O (Wiley, 2018-10-31)
      The parasitoid wasp family Ichneumonidae is among the most diverse groups of organisms, with conservative estimates suggesting that it contains more species than all vertebrates together. However, ichneumonids are also among the most severely understudied groups, and our understanding of their evolution is hampered by the lack of a robust higher‐level phylogeny of this group. Based on newly generated transcriptome sequence data, which were filtered according to several criteria of phylogenetic informativeness, we developed target DNA enrichment baits to capture 93 genes across species of Ichneumonidae. The baits were applied to DNA of 55 ichneumonids, with a focus on Pimpliformes, an informal group containing nine subfamilies. Phylogenetic trees were inferred under maximum likelihood and Bayesian approaches, at both the nucleotide and amino acid levels. We found maximum support for the monophyly of Pimpliformes but low resolution and very short branches close to its base, strongly suggesting a rapid radiation. Two genera and one genus‐group were consistently recovered in unexpected parts of the tree, prompting changes in their higher‐level classification: Pseudorhyssa Merrill, currently classified in the subfamily Poemeniinae, is transferred to the tribe Delomeristini within Pimplinae, and Hemiphanes Förster is moved from Orthocentrinae to Cryptinae. Likewise, the tribe Theroniini is resurrected for the Theronia group of genera (stat. rev.). Phylogenetic analyses, in which we gradually increased the numbers of genes, revealed that the initially steep increase in mean clade support slows down at around 40 genes, and consideration of up to 93 genes still left various nodes in the inferred phylogenetic tree poorly resolved. It remains to be shown whether more extensive gene or taxon sampling can resolve the early evolution of the pimpliform subfamilies.