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The development and impacts of coral-built structure
No full textNiche construction theory posits that organisms can systematically modify their environment in ways that alter the selection pressures experienced by themselves and other organisms. Stony corals are ecosystem engineers known for the complex structures they create that build up coral reef ecosystems. These structures are known to alter the local abiotic environment – for instance, by influencing light availability, flow regimes, and nutrient gradients – and the abiotic environment is also known to play a critical role in shaping coral survival, growth, and morphology. As such, corals present a promising but underexplored system for studying niche construction. This thesis sought to investigate potential patterns of niche construction in corals by examining their structural development and their effects on the fitness of the local coral community. First, I tracked the morphological development of wild coral colonies using biologically relevant metrics with links to organism performance and ecosystem function. The results revealed significant changes in shape as corals grew, suggesting that their ecological impacts shift throughout development as well. Second, I conducted an experiment to test how coral-built structures influence the survival and growth of nearby corals. I found that the presence of structure, whether living or dead increased survival, indicating that coral-built structures function as a form of ecological inheritance. Further, I identified specific morphological traits – namely, size, surface complexity, and volume compactness – as niche-constructing traits, due to their effect on both survival and growth of the local coral community, highlighting interesting demographic trade-offs. Overall, this thesis provides evidence of ecological niche construction in corals and identifies key traits that drive this process. In doing so, this research lays the foundation for future work investigating the evolutionary consequences of coral niche construction for coral reefs."This thesis was supported by a School of Biology Postgraduate Scholarship from the University of
St Andrews, two Santander Research Mobility Scholarships, a GRADskills Research Student Skills Development Fund grant, a St Leonard’s College Postgraduate Travel Award, and a Sir Ken Murray Endowment Fund travel grant.
Additional funding for this work and the data used in this work came from a National Science Foundation–Natural Environment Research Council Biological Oceanography Grant (1948946), the Warman Foundation, the European Union (CoralINT, GA 101044975), and an Ian Potter
Doctoral Fellowship at Lizard Island Research Station (awarded to Vivianna Brambilla)."--Fundin
Comparing visual and acoustic detectability of two coastal cetacean species off Sindhudurg, India, to better inform integrated survey protocol.
Get PDFFunding: Funding for the towed array was provided by The Marine Conservation Action Fund, New England Aquarium, USA. Funding for field data collection was provided by The Rufford Foundation, UK, The Wildlife Conservation Trust, Small Grants, India, The Marine Mammal Commission, USA and The Mangrove Foundation, India.The Indian Ocean humpback dolphin (Sousa plumbea) and the Indo-Pacific finless porpoise (Neophocaena phocaenoides) are resident to the inshore waters of India. Despite urgent conservation concerns facing both species, population assessments and long-term monitoring efforts face several challenges, particularly due to limitations in conducting conventional visual surveys. Our study explores the use of combined acoustic and visual surveys along a 376 km2 area off the Sindhudurg coast, India, to address these limitations. We begin by examining the two platforms for efficiency in species detection by comparing encounter rates across acoustic and visual methods. Acoustic (0.04 groups/km) and visual (0.03 groups/km) encounter rates for humpback dolphins do not show a stark difference. However, acoustic (0.12 groups/km) and visual (0.03 groups/km) encounter rates for finless porpoises vary greatly. Visual and acoustic group size estimates also vary for both species. We then use generalized additive mixed models (GAMM) to determine factors responsible for variation in detectability between the two platforms. Distance from shore and vessel traffic are variables affecting mixed detections of humpback dolphins. Acoustic detections for finless porpoises are most influenced by distance from shore and depth. Our findings highlight the importance of considering species-specific variations in acoustic and visual detectability when designing integrated surveys for multiple species.Peer reviewe
Raising the roof for rare metals : controls on rare earth mineralisation in magmatic roof-zones, Motzfeldt, Southern Greenland
No full textRare Earth Elements (REE) and other High Field Strength Elements (HFSE) are known as “critical metals”: raw materials with unstable supply lines essential for modern technology such as electric vehicles, renewable energy and defence systems. Deposits of these metals are often hosted by alkaline-silicate igneous rocks, however, models and processing pathways for these deposit types are underdeveloped compared to those hosting conventional resources.
This thesis concerns the deposit type “Alkaline Silicate Roof-Zones”, focussing primarily upon controls on REE mineralisation in these systems. This is investigated here through study of the REE-Nb-Ta-Zr mineralised roof-zone of the Motzfeldt Sø Centre, Southern Greenland. Field and lab work is presented investigating mineralogy and mineral chemistry through field relations, petrography and mineral chemical analysis (Electron Microscopy, EPMA, LA-ICP-MS).
Hydrothermal activity plays a key role in remobilising the REE and HFSE in the pyrochlore microsyenite as recorded by pyrochlore chemistry. Through use of an alteration proxy and textural analysis, it is shown REE and other A-site elements decrease during hydrothermal alteration, and Nb and B-site elements are released by dissolution of pyrochlore. At least two hydrothermal events are identified, recorded in the formation and later mobilisation of secondary crusts around pyrochlore. New field evidence identifies REE-HFSE mineralised hydrothermal chimney structures and metamorphosed xenoliths with REE-HFSE rich anatectic melts. SEM and EDS analysis reveals these features to be formed by the identified hydrothermal events through enrichment in HFSE, alkalis, F and Fe. These features are incorporated into the deposit model and have potential as exploration vectors and secondary mineral deposits. A method is developed to calculate REE deportment utilising WDS mapping and phase mapping software, identifying pyrochlore to be the major REE host in pyrochlore microsyenite (~60% of LREE), leading to discussion of appropriate processing methods and estimated yields of the most valuable REE species.
These findings significantly improve both the deposit model for and understanding of the complex magmatic, hydrothermal and metamorphic processes involved in the critical metal enrichment of alkaline silicate roof zones and other alkaline rocks worldwide
Fragmentation and the preface paradox
Get PDFThe preface paradox is often taken to show that beliefs can be individually rational but jointly inconsistent. However, this received conflict between rationality and consistency is unfounded. This paper seeks to show that no rational beliefs are actually inconsistent in the preface paradoxPeer reviewe
A non-human primate combinatorial system for long-distance communication
Get PDFFunding: Research was funded by the Swiss National Science Foundation (Project Grant 310030_185324 to KZ; NCCR Evolving Language, Agreement #51NF40_180888; and PCEFP1_186841 to SM).Complex vocal systems are thought to evolve if individuals are regularly challenged by complex social decision-making, the social complexity hypothesis. We tested this idea on a West African forest non-human primate, the Olive colobus monkey, a highly cryptic species with very little social behavior and very small group sizes, factors unlikely to favor the evolution of complex communication. The species also has an unusual fission-fusion social system, with group members regularly spending considerable amounts of time with neighboring groups. As predicted by the social complexity hypothesis, we only found a very basic repertoire of two call types in this species, produced by both males and females. However, the calls were astonishingly loud, never uttered alone but in syntactically structured sequences assembled along a set of rules. We concluded that the Olive colobus monkeys have evolved a combinatorial system to interact with distant group members.Peer reviewe
Traversing the multiple nested geographies of NUTs based entrepreneurial ecosystems
Get PDFFunding: UK Economic and Social Research Council (ES/W010259/1).Entrepreneurial Ecosystems (EEs) have quickly become a key lens for exploring regional entrepreneurial phenomena. Thus far there appears little consensus around the most relevant geographical unit of analysis for examining EEs however, both from a theoretical and an empirical perspective. In this paper, we set out to test whether wider EE geographical units (such as UK regions) have any meaningful relevance to the small firms and their business operations. To address this concern this paper undertakes an empirical analysis of a loan guarantee scheme in the UK, the Recovery Loan Scheme (RLS). Through the empirical lens of the UK SME support scheme, the RLS, we test the relevance of different levels of EE geographical units including NUTS 1, NUTS 2 and NUTS 3. In the case of the UK, which is a diverse collection of nations (England, and three devolved nations, Scotland, Wales, and Northern Ireland), we found that the three devolved nations, and also London shows much larger and stronger higher order spatial effects on their lower order constituent spatial levels. This suggests that outside of London, and the devolved nations, simply analysing NUTS 1 regions does not appear to be the appropriate level if we want to understand the inherent spatial dynamics of small firm ecosystems. Rather, we need to go to smaller spatial levels to establish the true nature of the ecosystem relevant to the small firm. The policy implications point toward the need for properly tailored localised policy.Peer reviewe
God as moral anti-examplar in Spinoza
Get PDFThis paper addresses the question of whether Spinoza subscribes to moral exemplarism, defined as any moral theory including the idea that it is morally good, right, virtuous, praiseworthy, or obligatory to emulate certain figures identified as moral exemplars. The answer is given at multiple levels. At one level, Spinoza endorsed moral exemplarism as a descriptive theory of how we make moral judgements, but does not endorse those judgements. At another level he endorses judgements of good and bad based on conformity to a constructed exemplar of human nature, although the endorsement is perhaps pragmatic rather than moral. At a third level, Spinoza offers as the highest ethical ideal the emulation of God. But since Spinoza’s God is a being devoid of goals and even of any determinate character, emulating it seems to mean rejecting the whole ethical project of trying to find an exemplar to guide one’s moral choices and development.Peer reviewe
Mixed-species fish shoals : any port in a storm?
Get PDFFunding: N.A.R. Jones was supported by a Humboldt Research Fellowship.Mixed-species fish shoals are common, and form for a variety of reasons. We suggest that short term mixed-species shoals, that persist for minutes or hours, might form because lone individuals (or small groups) of one species might benefit from joining larger groups of heterospecifics to reduce predation risk. We carried out a literature survey, which revealed that mixed-species groups seldom contain equal numbers of species; rather one or two dominate, with others present as small minorities. Furthermore, we found that the proportion of minority species decreases as absolute shoal size increases. We suggest that although minority members of mixed-species groups might suffer costs associated with being odd, they might often still do better by grouping than if they remained alone. We term this ‘any port in a storm’. This explanation makes several predictions and assumptions, and we suggest approaches for testing these. For example, minority members should attempt to form single-species groups when the opportunity arises, and mixed species-groups should coincide with periods of heightened predation risk. Mixed-species groups may be influenced by the distribution of shelter, and further work is needed to disentangle the relative importance of aggregation versus social attraction in the formation of mixed-species-shoals. This account of mixed-species groups does not exclude other ecological functions, such as forager-guild formation, but may explain cases of short-term associations of minority species with numerically dominant species in fish shoals. Our predictions are readily testable, and we hope they spur further research in this area.Peer reviewe
Intra-population isotopic niche variation in common bottlenose dolphins (Tursiops truncatus) from the northern Adriatic Sea
Get PDFAmong-individual variability in animal behaviour and diet leads to a plethora of mini-niches within a population's general niche. Such variability is directly or indirectly linked to inter- and intra-specific competition, behavioural adaptation and variation in foraging tactics, which may lead to evolutionary divergence and speciation but is also relevant to population resilience and conservation. We used boat surveys, photo-identification techniques, biopsy sampling and stable isotope analysis (δ13C, δ15N) to study the intra-population isotopic niche variation in an apex predator, the common bottlenose dolphin (Tursiops truncatus), in the northern Adriatic Sea. We integrated this information with various demographic, behavioural, social and temporal parameters from long-term re-sighting histories of photo-identified individuals, as well as with information on persistent organic pollutant concentrations (PCB and DDE). Despite overlap, we found marked differences in overall isotopic niche among different social groups within the same population, consistent with differences in behaviour. However, interestingly, differences in δ15N values, a proxy for trophic level, did not correlate with persistent pollutant concentrations. This study provides new insight into fine-scale variability and drivers of intra-population partitioning in an apex predator, which may be relevant when evaluating multiple and cumulative impacts affecting marine conservation.Peer reviewe
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