Recent Submissions

  • Of apples and oranges? The evolution of “monogamy” in non-human primates

    Huck, Maren; Di Fore, Anthony; Fernandez-Duque, Eduardo; University of Derby, Environmental Sustainability Research Centre; University of Texas at Austin; Yale University (Frontiers, 2020-01-10)
    Behavioral ecologists, evolutionary biologists, and anthropologists have been long fascinated by the existence of “monogamy” in the animal kingdom. Multiple studies have explored the factors underlying its evolution and maintenance, sometimes with contradicting and contentious conclusions. These studies have been plagued by a persistent use of fuzzy terminology that often leads to researchers comparing “apples with oranges” (e.g., comparing a grouping pattern or social organization with a sexual or genetic mating system). In this review, we provide an overview of research on “monogamy” in mammals generally and primates in particular, and we discuss a number of problems that complicate comparative attempts to understand this issue. We first highlight why the muddled terminology has hindered our understanding of both a rare social organization and a rare mating system. Then, following a short overview of the main hypotheses explaining the evolution of pair-living and sexualmonogamy, we critically discuss various claims about the principal drivers of “monogamy” that have been made in several recent comparative studies.We stress the importance of using only high quality and comparable data. We then propose that a productive way to frame and dissect the different components of pair-living and sexual or genetic monogamy is by considering the behavioral and evolutionary implications of those components from the perspectives of all participants in a species’ social system. In particular, we highlight the importance of integrating the perspective of “floater” individuals and considering their impacts on local operational sex ratios, competition, and variance in reproductive success across a population. We stress that pair-living need not imply a reduced importance of intrasexual mate competition, a situation that may have implications for the sexual selection potential that have not yet been fully explored. Finally, we note that there is no reason to assume that different taxa and lineages, even within the same radiation, should follow the same pathway to or share a unifying evolutionary explanation for “monogamy”. The study of the evolution of pair-living, sexual monogamy, and genetic monogamy remains a challenging and exciting area of research.
  • Untangling the origin of ghost gear within the Maldivian archipelago and its impact on olive ridley (Lepidochelys olivacea) populations

    Stelfox, M; Bulling, M; Sweet, M; University of Derby; Olive Ridley Project, Cheshire (Inter-Research Science Center, 2019-12-12)
    There is little documentation available on the impact of abandoned, lost or discarded fishing nets (‘ghost nets’) on turtle populations. Here, we utilise data collected over a 5 year period to assess (1) if a particular net type or characteristic was identifiable as entangling more turtles and (2) if particular fishing practices (i.e. types of nets) could be managed to reduce turtle entanglement in the Maldivian archipelago. A total of 131 turtles were entangled in the 752 reported ghost nets, and olive ridley turtles Lepidochelys olivacea appeared to be the most vulnerable (making up 97% of entangled turtles). However, we estimate that the 752 nets in this study, reported over a 51 month period, could have entangled between 3400 and 12200 turtles across the Indian Ocean prior to being detected in the Maldives. Mesh size, seasonality (i.e. north east monsoon), and the presence of floats were all identified as variables significantly affecting the likelihood of turtle entanglement. The probability of entanglement increased as the mesh size increased but decreased when floats were present. Additionally, turtles were more likely to be entangled during the north east monsoon when currents flow from east to west. Cluster analysis indicated that there were at least 11 broadly assigned net types found floating in the study area, and these were dominated by trawl and gill nets. Our analyses highlight the need for a detailed database of existing gear types coupled with gear marking to improve traceability of ghost nets in the Indian Ocean.
  • The development of an eDNA based detection method for the invasive shrimp Dikerogammarus haemobaphes

    Mauvisseau, Quentin; Troth, Chris; Young, Emily; Burian, Alfred; Sweet, Michael; University of Derby; Surescreen Scientifics Ltd, Morley (Regional Euro-Asian Biological Invasions Centre Oy (REABIC), 2019-06-06)
    Dikerogammarus haemobaphes is a freshwater gammarid crustacean native to the Ponto-Caspian region. However, the species is rapidly spreading throughout Western Europe and is classed as a highly invasive species. Here we present a novel eDNA assay aimed at detecting D. haemobaphes and demonstrate its suitability with validation steps conducted in-silico (computer simulations), ex-situ (test of specificity using closely related species) and in-situ (within the field). A survey of freshwater systems in the West-Midlands, United Kingdom, highlighted that D. haemobaphes was present in 26 out of the 39 sites assessed. We conclude that eDNA detection for D. haemobaphes is a promising tool for assessing and mapping the presence/distribution of this invasive amphipod.
  • Early detection of an emerging invasive species: eDNA monitoring of a parthenogenetic crayfish in freshwater systems

    Mauvisseau, Quentin; Sweet, Michael; Lyko, Frank; Andriantsoa, Ranja; Tonges, Sina; University of Derby; Surescreen Scientifics Ltd, Morley; German Cancer Research Center, Germany (Regional Euro-Asian Biological Invasions Centre Oy (REABIC), 2019-06-06)
    Procambarus virginalis, also known as the Marmorkrebs is a highly invasive crayfish species characterized by parthenogenetic reproduction. As conservation management plans rely on the accuracy of the presence and distribution information of invasive species, a reliable method is needed for detecting such species in aquatic systems. We developed and validated a qPCR-based assay for monitoring P. virginalis at low abundance, by detecting their eDNA traces left in freshwater systems. We were able to implement this new assay in-situ at two separate lakes in Germany, where the crayfish were known to be present. Furthermore, we did not detect the pathogenic fungus Aphanomyces astaci in the locations where the Marmorkrebs were detected. We conclude that the use of eDNA is therefore a reliable tool for the early detection of this “perfect invader”.
  • Customized medicine for corals

    Sweet, Michael; Peixoto, Raquel; Bourne, David; University of Derby; Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; IMAM-AquaRio – Rio de Janeiro Aquarium Research Center, Rio de Janeiro, Brazil; University of California; James Cook University, Townsville, QLD, Australia; Australian Institute of Marine Science, Townsville, QLD, Australia (Frontiers, 2019-11-13)
  • Compositional homogeneity in the pathobiome of a new, slow-spreading coral disease

    Sweet, Michael; Burian, Alfred; Fifer, James; Bulling, Mark; Elliott, David; Raymundo, Laurie; University of Derby; University of Guam (Springer Science and Business Media LLC, 2019-11-22)
    Coral reefs face unprecedented declines in diversity and cover, a development largely attributed to climate change-induced bleaching and subsequent disease outbreaks. Coral-associated microbiomes may strongly influence the fitness of their hosts and alter heat tolerance and disease susceptibility of coral colonies. Here, we describe a new coral disease found in Micronesia and present a detailed assessment of infection-driven changes in the coral microbiome. Combining field monitoring and histological, microscopic and next-generation barcoding assessments, we demonstrate that the outbreak of the disease, named ‘grey-patch disease’, is associated with the establishment of cyanobacterial biofilm overgrowing coral tissue. The disease is characterised by slow progression rates, with coral tissue sometimes growing back over the GPD biofilm. Network analysis of the corals’ microbiome highlighted the clustering of specific microbes which appeared to benefit from the onset of disease, resulting in the formation of ‘infection clusters’ in the microbiomes of apparently healthy corals. Our results appear to be in contrast to the recently proposed Anna-Karenina principle, which states that disturbances (such as disease) trigger chaotic dynamics in microbial communities and increase β-diversity. Here, we show significantly higher community similarity (compositional homogeneity) in the pathobiome of diseased corals, compared to the microbiome associated with apparently healthy tissue. A possible explanation for this pattern is strong competition between the pathogenic community and those associated with the ‘healthy’ coral holobiont, homogenising the composition of the pathobiome. Further, one of our key findings is that multiple agents appear to be involved in degrading the corals’ defences causing the onset of this disease. This supports recent findings indicating a need for a shift from the one-pathogen-one-disease paradigm to exploring the importance of multiple pathogenic players in any given disease.
  • Combining ddPCR and environmental DNA to improve detection capabilities of a critically endangered freshwater invertebrate

    Mauvisseau, Quentin; Davy-Bowker, John; Bulling, Mark; Brys, Rein; Neyrinck, Sabrina; Troth, Christopher; Sweet, Michael; University of Derby; Freshwater Biological Association, Dorset; Natural History Museum, London; et al. (Springer Science and Business Media LLC, 2019-10-01)
    Isogenus nubecula is a critically endangered Plecoptera species. Considered extinct in the UK, I. nubecula was recently rediscovered (in one location of the River Dee, Wales), after 22 years of absence. In a similar way to many other species of Perlodidae, I. nubecula could be utilised as a bio-indicator, for assessing water quality and health status of a given freshwater system. However, conventional monitoring of invertebrates via kick-sampling, is invasive and expensive (time consuming). Further, such methods require a high level of taxonomic expertise. Here, we compared the traditional kick-sampling method with the use of eDNA detection using qPCR and ddPCR-analyses. In spring 2018, we sampled eDNA from twelve locations on the River Dee. I. nubecula was detected using kick-sampling in five of these locations, three locations using both eDNA detection and kick-sampling and one location using eDNA detection alone – resulting in a total of six known and distinct populations of this critically endangered species. Interestingly, despite the eDNA assay being validated in vitro and in silico, and results indicating high sensitivity, qPCR analysis of the eDNA samples proved to be ineffective. In contrast, ddPCR analyses resulted in a clear detection of I. nubecula at four locations suggesting that inhibition most likely explains the large discrepancy between the obtained qPCR and ddPCR results. It is therefore important to explore inhibition effects on any new eDNA assay. We also highlight that ddPCR may well be the best option for the detection of aquatic organisms which are either rare or likely to shed low levels of eDNA into their environment.
  • Ex situ co culturing of the sea urchin, Mespilia globulus and the coral Acropora millepora enhances early post-settlement survivorship

    Craggs, Jamie; Guest, James; Bulling, Mark; Sweet, Michael; University of Derby; Newcastle University (Springer Science and Business Media LLC, 2019-09-10)
    Reef restoration efforts, utilising sexual coral propagation need up-scaling to have ecologically meaningful impact. Post-settlement survival bottlenecks, in part due to competitive benthic algae interactions should be addressed, to improve productivity for these initiatives. Sea urchins are keystone grazers in reef ecosystems, yet feeding behaviour of adults causes physical damage and mortality to developing coral spat. To investigate if microherbivory can be utilised for co-culture, we quantitatively assessed how varying densities of juvenile sea urchins Mespilia globulus (Linnaeus, 1758), reared alongside the coral Acropora millepora (Ehrenberg, 1834) effected survival and growth of coral recruits. Spawning of both species were induced ex situ. A comparison of A. millepora spat reared in three M. globulus densities (low 16.67 m−2, medium 37.50 m−2, high 75.00 m−2) and a non-grazed control indicated coral survival is significantly influenced by grazing activity (p < 0.001) and was highest in the highest density treatment (39.65 ± 10.88%, mean ± s.d). Urchin grazing also significantly (p < 0.001) influenced coral size (compared to non-grazing control), with colonies in the medium and high-densities growing the largest (21.13 ± 1.02 mm & 20.80 ± 0.82, mean ± s.e.m). Increased urchin density did however have a negative influence on urchin growth, a result of limited food availability.
  • Influence of accuracy, repeatability and detection probability in the reliability of species-specific eDNA based approaches

    Mauvisseau, Quentin; Burian, Alfred; Gibson, Ceri; Brys, Rein; Ramsey, Andrew; Sweet, Michael; University of Derby; Freshwater Biological Association, Cumbria; Research Institute for Nature and Forest, Belgium (Springer, 2019-01-24)
    Environmental DNA (eDNA) barcoding has a high potential to increase the cost-efficiency of species detection and monitoring in aquatic habitats. However, despite vast developments in the field, many published assays often lack detailed validation and there is little to no commonly (agreed upon) standardization of protocols. In this study, we evaluated the reliability of eDNA detection and quantification using published primers and assays targeting the Freshwater Pearl Mussel as a model organism. We first assessed limits of detection for two different target genes (COI and 16S) following the MIQE guidelines, and then tested the reliability of quantification in a double-blind mesocosm experiment. Our results reveal that different methodological indicators, namely accuracy, repeatability and detection probability affected the reliability of eDNA measurement at the different levels tested. The selection of the optimal analytical method was mainly determined by detection probability. Both the COI and 16S assays were highly specific for the targeted organism and showed similar accuracy and repeatability, whilst the limit of detection was clearly lower for the COI based approach. In contrast, the reliability of eDNA quantification hinged on repeatability, reflected by the scattering (r2 = 0.87) around the relationship between eDNA and mussel density in mesocosms. A bootstrapping approach, which allowed for the assignment of measures associated with repeatability of samples, revealed that variability between natural replicates (i.e. accuracy) strongly influenced the number of replicates required for a reliable species detection and quantification in the field.
  • Elemental ratios link environmental change and human health

    Paseka, Rachel E.; Bratt, Anika R.; MacNeill, Keeley L.; Burian, Alfred; See, Craig R.; University of Derby (Frontiers, 2019-10-10)
    Humans have fundamentally altered the cycling of multiple elements on a global scale. These changes impact the structure and function of terrestrial and aquatic ecosystems, with many implications for human health. Most prior studies linking biogeochemical changes to human health have evaluated the effects of single elements in isolation. However, the relative availability of multiple elements often determines the biological impact of shifts in the concentration of a single element. The balance of multiple elements is the focus of ecological stoichiometry, which highlights the importance of elemental ratios in biological function across all systems and scales of organization. Consequently, ecological stoichiometry is a promising framework to inform research on the links between global changes to elemental cycles and human health. We synthesize evidence that elemental ratios link global change with human health through biological processes occurring at two scales: in the environment (natural ecosystems and food systems) and within the human body. Elemental ratios in the environment impact the key ecosystem processes of productivity and biodiversity, both of which contribute to the production of food, toxins, allergens, and parasites. Elemental ratios in diet impact processes within the human body, including the function and interactions of the immune system, parasites, and the non-pathogenic microbiome. Collectively, these stoichiometric effects contribute to a wide range of non-infectious and infectious diseases. By describing stoichiometric mechanisms linking global change, ecological processes, and human health, we hope to inspire future empirical and theoretical research on this theme.
  • A community-based evaluation of population growth and agro-pastoralist resilience in Sub-Saharan drylands

    Karaya, Rebecca; Wernersson, Julia E.V.; Egberth, Mikael; Lokorwa, Benjamin; Nyberg, Gert; Alfred, Burian; University of Derby (Elsevier, 2018-12-14)
    Human population growth is considered together with climate warming as major driver of change in Sub-Saharan Africa. Research on the implications of increased population densities often utilises community knowledge but without incorporating the view of local stakeholders. In this study, we applied a community-centred approach to assess direct and indirect consequences of population growth in drylands of north-western Kenya. Combined social, agricultural and geo-spatial analyses allowed us to identify major system transitions, determine their linkage to population growth and deduce consequences for local livelihoods and community resilience.Community-members reported positive and negative consequences of fourfold population growth since 1974 but evaluated its overall effect as clearly beneficial. This overall positive effect was based on both, positive developments and the successful mitigation of potential system stressors. First, food security was maintained despite high growth rates because a shift from migratory pastoralism to a more labour-intensive agro-pastoralist system helped to increase agricultural productivity. Additionally, land-use changes were linked to land privatisation and improved erosion protection on private land, decoupling population growth from environmental degradation.We detected, however also early warning signs of reduced community resilience as households were unable to fully recover livestock densities after catastrophic events. A population-growth driven reduction in household land-sizes and the decreased monetary value of agricultural production were identified as drivers of this development. The extrapolation of our results to establish a general relationship between population densities, land-use and household resilience in Sub-Saharan drylands suggest that further system transformations will be required to ensure regional food-security.
  • Nutrient deficiencies and the restriction of compensatory mechanisms in copepods

    Burian, Alfred; Grosse, Julia; Winder, Monika; Boschker, Henricus T.S.; Stockholm University; Utrecht University (British Ecological Society, 2017-11-14)
    The flexible regulation of feeding behaviour and nutrient metabolism is a prerequisite for consumers to grow and survive under variable food conditions. Thus, it is essential to understand the ecological trade-offs that restrict regulatory mechanisms in consumers to evaluate the consequences of nutrient limitations for trophic interactions. Here, we assessed behavioural and physiological adjustments to nutrient deficiencies in copepods and examined whether energy limitation, food digestibility or co-limitation with a second nutrient restricted compensatory mechanisms. A combination of C-13-labelling and compound-specific stable isotope measurements revealed that copepods compensated nitrogen deficiencies by raising retention efficiencies of amino acids (AA). The costs of higher retention efficiencies were reflected in the doubling of structural fatty acids (FA), probably required for morphological adaptations of the gut. A depletion of highly unsaturated FA in storage lipids and their selective retention suggested that these FA became co-limiting and restricted a further increase in AA retention efficiencies. Copepods feeding on phosphorus-limited algae showed a marked increase in ingestion rates but were not fully able to compensate dietary deficiencies. The increase in ingestion rates was thereby not restricted by higher foraging costs because energy storage in copepods increased. Instead, thicker cell walls of nutrient-limited algae indicated that algal digestion resistance restricted the extent of surplus feeding. The strongly nutrient-specific response of copepods had large implications for recycling rates, growth efficiencies and the potential top-down control at the plant-animal interface. Compensatory mechanisms to mitigate nutrient deficiencies are therefore an essential aspect of trophic interactions and have the potential to alter the structure of food web.
  • Use of environmental management systems to mitigate urban pollution

    Horry, Rosemary; University of Derby; University of West of England (Wiley, 2018-10-16)
    An environmental management system (EMS) is an instrument that can help organizations to manage and positively improve their level of impact on the environment. This chapter provides an overview of the importance for organizations to have an established EMS in place. It employs a series of infamous case studies to highlight where an EMS could have served as a useful means of mitigating pollution events. The chapter identifies a number of organizational benefits of implementing an EMS. All businesses face a challenge in terms of their environmental impacts; environmental work is not just a concern for multinational organizations, which is sometimes how it is viewed. The chapter describes some of the well known pollution incidents and how they were managed. Some of these impacts were mitigated through the use of legislation.
  • Madagascar's escape from Africa: A high-resolution plate reconstruction for the Western Somali Basin and implications for supercontinent dispersal

    Phethean, Jordan; Kalnins, Lara M.; van Hunen, Jeroen; Biffi, Paolo G.; Davies, Richard J.; McCaffrey, Ken J.W.; Durham University; University of Edinburgh; S.G.E.G ENI, Milan, Italy; Newcastle University (American Geophysical Union (AGU), 2016-12-29)
    Accurate reconstructions of the dispersal of supercontinent blocks are essential for testing continental breakup models. Here, we provide a new plate tectonic reconstruction of the opening of the Western Somali Basin during the breakup of East and West Gondwana. The model is constrained by a new comprehensive set of spreading lineaments, detected in this heavily sedimented basin using a novel technique based on directional derivatives of free‐air gravity anomalies. Vertical gravity gradient and free‐air gravity anomaly maps also enable the detection of extinct mid‐ocean ridge segments, which can be directly compared to several previous ocean magnetic anomaly interpretations of the Western Somali Basin. The best matching interpretations have basin symmetry around the M0 anomaly; these are then used to temporally constrain our plate tectonic reconstruction. The reconstruction supports a tight fit for Gondwana fragments prior to breakup, and predicts that the continent‐ocean transform margin lies along the Rovuma Basin, not along the Davie Fracture Zone (DFZ) as commonly thought. According to our reconstruction, the DFZ represents a major ocean‐ocean fracture zone formed by the coalescence of several smaller fracture zones during evolving plate motions as Madagascar drifted southwards, and offshore Tanzania is an obliquely rifted, rather than transform, margin. New seismic reflection evidence for oceanic crust inboard of the DFZ strongly supports these conclusions. Our results provide important new constraints on the still enigmatic driving mechanism of continental rifting, the nature of the lithosphere in the Western Somali Basin, and its resource potential.
  • Evidence for basement reactivation during the opening of the Labrador sea from the Makkovik province, Labrador, Canada: insights from field data and numerical models

    Peace, Alexander; Dempsey, Edward; Schiffer, Christian; Welford, J.; McCaffrey, Ken; Imber, Jonathan; Phethean, Jordan; Durham University; Memorial University of Newfoundland, Canada; University of Hull; et al. (MDPI AG, 2018-08-20)
    The onshore exposures adjacent to modern, offshore passive continental margins may preserve evidence of deformation from the pre-, syn-, and post-rift phases of continental breakup that allow us to investigate the processes associated with and controlling rifting and breakup. Here, we characterize onshore brittle deformation and pre-rift basement metamorphic mineral fabric from onshore Labrador in Eastern Canada in the Palaeoproterozoic Aillik Domain of the Makkovik Province. Stress inversion (1) was applied to these data and then compared to (2) numerical models of hybrid slip and dilation tendency, (3) independent calculations of the regional geopotential stress field, and (4) analyses of palaeo-stress in proximal regions from previous work. The stress inversion shows well-constrained extensional deformation perpendicular to the passive margin, likely related to pre-breakup rifting in the proto-Labrador Sea. Hybrid slip and dilatation analysis indicates that inherited basement structures were likely oriented in a favorable orientation to be reactivated during rifting. Reconstructed geopotential stresses illuminate changes of the ambient stress field over time and confirm the present paleo-stress estimates. The new results and numerical models provide a consistent picture of the late Mesozoic-Cenozoic lithospheric stress field evolution in the Labrador Sea region. The proto-Labrador Sea region was characterized by a persistent E–W (coast-perpendicular) extensional stress regime, which we interpret as the pre-breakup continental rifting that finally led to continental breakup. Later, the ridge push of the Labrador Sea spreading ridge maintained this general direction of extension. We see indications for anti-clockwise rotation of the direction of extension along some of the passive margins. However, extreme persistent N–S-oriented extension as indicated by studies further north in West Greenland cannot be confirmed.
  • An evaluation of Mesozoic rift-related magmatism on the margins of the Labrador Sea : implications for rifting and passive margin asymmetry.

    Phethean, Jordan; Peace, Alexander; McCaffrey, Ken; Imber, Jonathan; Nowell, Geoff; Gerdes, Keith; Dempsey, Edward; Durham University; Shell International (The Geological Society of America, 2016-09-29)
    The Labrador Sea is a small (~900 km wide) ocean basin separating southwest Greenland from Labrador, Canada. It opened following a series of rifting events that began as arly as the Late Triassic or Jurassic, culminating in a brief period of seafloor spreading commencing by polarity chron 27 (C27; Danian) and ending by C13 (Eocene-Oligocene oundary). Rift-related magmatism has been documented on both conjugate margins of the Labrador Sea. In southwest Greenland this magmatism formed a major coast-parallel dike swarm as well as other smaller dikes and intrusions. Evidence for rift-related magmatism on the conjugate Labrador margin is limited to igneous lithologies found in deep offshore exploration wells, mostly belonging to the Alexis Formation, along with a postulated Early Cretaceous nephelinite dike swarm (ca. 142 Ma) that crops out onshore, near Makkovik, Labrador. Our field observations of this Early Cretaceous nephelinite suite lead us to conclude that the early rift-related magmatism exposed around Makkovik is volumetrically and spatially limited compared to the contemporaneous magmatism on the conjugate southwest Greenland margin. This asymmetry in the spatial extent of the exposed onshore magmatism is consistent with other observations of asymmetry between the conjugate margins of the Labrador Sea, including the total sediment thickness in offshore basins, the crustal structure, and the bathymetric profile of the shelf width. We propose that the magmatic and structural asymmetry observed between these two conjugate margins is consistent with an early rifting phase dominated by simple shear rather than pure shear deformation. In such a setting Labrador would be the lower plate margin to the southwest Greenland upper plate.
  • The Jan Mayen microplate complex and the Wilson cycle

    Schiffer, Christian; Peace, Alexander; Phethean, Jordan; Gernigon, Laurent; McCaffrey, Ken; Petersen, Kenni D.; Foulger, Gillian; Durham University; Memorial University of Newfoundland, Canada; Geological Survey of NorwayLeiv; et al. (Geological Society of London, 2018-02-01)
    The opening of the North Atlantic region was one of the most important geodynamic events that shaped the present day passive margins of Europe, Greenland and North America. Although well-studied, much remains to be understood about the evolution of the North Atlantic, including the role of the Jan Mayen microplate complex. Geophysical data provide an image of the crustal structure of this microplate and enable a detailed reconstruction of the rifting and spreading history. However, the mechanisms that cause the separation of microplates between conjugate margins are still poorly understood. We assemble recent models of rifting and passive margin formation in the North Atlantic and discuss possible scenarios that may have led to the formation of the Jan Mayen microplate complex. This event was probably triggered by regional plate tectonic reorganizations rejuvenating inherited structures. The axis of rifting and continental break-up and the width of the Jan Mayen microplate complex were controlled by old Caledonian fossil subduction/suture zones. Its length is related to east–west-oriented deformation and fracture zones, possibly linked to rheological heterogeneities inherited from the pre-existing Precambrian terrane boundaries.
  • A review of Pangaea dispersal and large igneous provinces – In search of a causative mechanism

    Peace, A.L.; Phethean, Jordan; Franke, D.; Foulger, G.R.; Schiffer, C.; Welford, J.K.; McHone, G.; Rocchi, S.; Schnabel, M.; Doré, A.G.; et al. (Elsevier, 2019-07-22)
    The breakup of Pangaea was accompanied by extensive, episodic, magmatic activity. Several Large Igneous Provinces (LIPs) formed, such as the Central Atlantic Magmatic Province (CAMP) and the North Atlantic Igneous Province (NAIP). Here, we review the chronology of Pangaea breakup and related large-scale magmatism. We review the Triassic formation of the Central Atlantic Ocean, the breakup between East and West Gondwana in the Middle Jurassic, the Early Cretaceous opening of the South Atlantic, the Cretaceous separation of India from Antarctica, and finally the formation of the North Atlantic in the Mesozoic-Cenozoic. We demonstrate that throughout the dispersal of Pangaea, major volcanism typically occurs distal from the locus of rift initiation and initial oceanic crust accretion. There is no location where extension propagates away from a newly formed LIP. Instead, LIPs are coincident with major lithosphere-scale shear movements, aborted rifts and splinters of continental crust rifted far out into the oceanic domain. These observations suggest that a fundamental reappraisal of the causes and consequences of breakup-related LIPs is in order.
  • Slow on the draw: the representation of turtles, terrapins and tortoises in children’s literature

    Beaumont, Ellen S.; Briers, Erin; Harrison, Emma; University of Derby; The Orkney Campus of Heriot-Watt University, Stromness (Springer, 2019-08-08)
    Children’s picture books, both fiction and non-fiction, play a vital role in introducing the reader to the natural world. Here we examine the representation of turtles, terrapins and tortoises (Testudines) in 204 English language picture books and find a mean of 3.9 (SD 9.1) basic biological errors per book. Only 83 (40.7%) of the examined books were found to be error-free in the representation of Testudines, with no significant improvement in biological accuracy being observed over time (book publication date range 1974–2017). Suggestions are made as to how biological accuracy of children’s literature could be improved to help foster children’s understanding and wonder of the natural world. Fantasy and imagination have an important role within children’s literature, but here it is argued that the books children read should support future generations having sufficient understanding of the natural world to imagine the solutions to current environmental problems. A role of children’s picture books should not be to reinforce biological illiteracy.
  • Lower crustal heterogeneity and fractional crystallisation control evolution of small volume magma batches at ocean island volcanoes (Ascension Island, South Atlantic)

    Chamberlain, Katy J.; Barclay, Jenni; Preece, Katie; Brown, Richard J.; Davidson, Jon P.; Durham University; University of Derby; University of East Anglia; Swansea University (Oxford University Press, 2019-08-10)
    Ocean island volcanoes erupt a wide range of magmatic compositions via a diverse range of eruptive styles. Understanding where and how these melts evolve is thus an essential component in the anticipation of future volcanic activity. Here we examine the role of crustal structure and magmatic flux in controlling the location, evolution and ultimately composition of melts at Ascension Island. Ascension Island, in the south Atlantic, is an ocean island volcano which has produced a continuum of eruptive compositions from basalt to rhyolite in its 1-million-year subaerial eruptive history. Volcanic rocks broadly follow a silica undersaturated subalkaline evolutionary trend and new data presented here show a continuous compositional trend from basalt through trachyte to rhyolite. Detailed petrographic observations are combined with in-situ geochemical analyses of crystals and glass, and new whole rock major and trace element data from mafic and felsic pyroclastic and effusive deposits that span the entire range in eruptive ages and compositions found on Ascension Island. These data show that extensive fractional crystallisation is the main driver for the production of felsic melt for Ascension Island; a volcano built on thin, young, oceanic crust. Strong spatial variations in the compositions of erupted magmas reveals the role of a heterogeneous lower crust: differing degrees of interaction with a zone of plutonic rocks are responsible for the range in mafic lava composition, and for the formation of the central and eastern felsic complexes. A central core of nested small-scale plutonic, or mush-like, bodies inhibits the ascent of mafic magmas, allowing sequential fractional crystallisation within the lower crust, and generating felsic magmas in the core of the island. There is no evidence for magma mixing preserved in any of the studied eruptions, suggesting that magma storage regions are transient, and material is not recycled between eruptions.

View more