RSS 1.0Biological Sciences
The Department of Biological Sciences has an expanding research base, which, in addition to providing leading researchers of national and international standing in these areas, most importantly underpins the delivery of teaching. Research in Biological Sciences at Chester can be divided into three broad groups of expertise, namely Animal Behaviour and Conservation, Food Nutrition and Health, and Stress and Disease.
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The role of brain size on mammalian population densities1. The local abundance or population density of different organisms often varies widely. Understanding what determines this variation is an important, but not yet fully resolved question in ecology. Differences in population density are partly driven by variation in body size and diet among organisms. Here we propose that the size of an organism’ brain could be an additional, overlooked, driver of mammalian population densities. 2. We explore two possible contrasting mechanisms by which brain size, measured by its mass, could affect population density. First, because of the energetic demands of larger brains and their influence on life history, we predict mammals with larger relative brain masses would occur at lower population densities. Alternatively, larger brains are generally associated with a greater ability to exploit new resources, which would provide a competitive advantage leading to higher population densities among large‐brained mammals. 3. We tested these predictions using phylogenetic path analysis, modelling hypothesized direct and indirect relationships between diet, body mass, brain mass and population density for 656 non‐volant terrestrial mammalian species. We analysed all data together and separately for marsupials and the four taxonomic orders with most species in the dataset (Carnivora, Cetartiodactyla, Primates, Rodentia). 4. For all species combined, a single model was supported showing lower population density associated with larger brains, larger bodies and more specialized diets. The negative effect of brain mass was also supported for separate analyses in Primates and Carnivora. In other groups (Rodentia, Cetartiodactyla and marsupials) the relationship was less clear: supported models included a direct link from brain mass to population density but 95% confidence intervals of the path coefficients overlapped zero. 5. Results support our hypothesis that brain mass can explain variation in species’ average population density, with large‐brained species having greater area requirements, although the relationship may vary across taxonomic groups. Future research is needed to clarify whether the role of brain mass on population density varies as a function of environmental (e.g. environmental stability) and biotic conditions (e.g. level of competition).
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Contrasting responses to salinity and future ocean acidification in arctic populations of the amphipod Gammarus setosusClimate change is leading to alterations in salinity and carbonate chemistry in arctic/sub-arctic marine ecosystems. We examined three nominal populations of the circumpolar arctic/subarctic amphipod, Gammarus setosus, along a salinity gradient in the Kongsfjorden-Krossfjorden area of Svalbard. Field and laboratory experiments assessed physiological (haemolymph osmolality and gill Na+/K+-ATPase activity, NKA) and energetic responses (metabolic rates, MO2, and Cellular Energy Allocation, CEA). In the field, all populations had similar osmregulatory capacities and MO2, but lower-salinity populations had lower CEA. Reduced salinity (S = 23) and elevated pCO2 (~1000 μatm) in the laboratory for one month increased gill NKA activities and reduced CEA in all populations, but increased MO2 in the higher-salinity population. Elevated pCO2 did not interact with salinity and had no effect on NKA activities or CEA, but reduced MO2 in all populations. Reduced CEA in lower-rather than higher-salinity populations may have longer term effects on other energy demanding processes (growth and reproduction).
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The long-term impact of infant rearing background on the behavioural and physiological stress response of adult common marmosets (Callithrix jacchus)Although triplet litters are increasing in captive colonies of common marmosets, parents can rarely rear more than two infants without human intervention. There is however much evidence that early life experience, including separation from the family, can influence both vulnerability and resilience to stress. The current study investigated the behavioural and hypothalamic pituitary adrenal (HPA) axis response to the routine stressor of capture and weighing in adult common marmosets (Callithrix jacchus), reared as infants under 3 different conditions: family-reared twins (n = 6 individuals), family-reared animals from triplet litters where only 2 remain (2stays: n = 8) and triplets receiving supplementary feeding from humans (n = 7). In the supplementary feeding condition, infants remained in contact with each other when they were removed from the family. There were no significant differences (P > 0.5) in cortisol level or behaviour between the rearing conditions. In all conditions, salivary cortisol decreased from baseline to post-capture, which was accompanied by increases in agitated locomotion. Family reared 2stays demonstrated significant cortisol decreases from baseline to post capture (post 5 min.: P = 0.005; post 30 min.: P = 0.018), compared to the other conditions. Family reared twins displayed significantly more behavioural changes following the stressor than the other conditions, including significant increases in scent marking (post 5 min. and post 30 min.: P = 0.028) and significant decreases in inactive alert (post 5 min.: P = 0005; post 30 min.: P = 0.018), calm locomotion (post 5 min.: P = 0.028; post 30 min.: P = 0.046) and proximity to partner (post 5 min.: P = 0.046). There were increases in behaviour suggesting reduced anxiety, including significantly more exploration post-capture in supplementary fed triplets (post 5 min.: P = 0.041), and significantly more foraging post capture in family reared 2stays (post 5 min. and post 30 min.: P = 0.039). However, as differences between rearing conditions were minimal, supplementary feeding of large litters of marmosets at this facility did not have a major effect on stress vulnerability, suggesting that this rearing practice may be the preferred option if human intervention is necessary to improve survival of large litters.
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Effects of a no-take reserve on mangrove fish assemblages: incorporating seascape 2 connectivityNo-take reserves (NTRs) have been effective at conserving fish assemblages in tropical systems such as coral reefs, but have rarely been evaluated in turbid tropical estuaries. The present study evaluated the effect of a mangrove NTR on the conservation of juvenile fish abundance, commercial fish biomass and biodiversity at the assemblage level, and the abundance of juveniles, target and non-target adults at the family level. The evaluation incorporated one aspect of seascape connectivity, namely proximity to the sea, or in this case, the Gulf of Paria. Linear mixed models showed that the NTR had a positive effect only on species richness at the assemblage level. However, juvenile fish abundance, commercial fish biomass, taxonomic distinctness and functional diversity were not enhanced in the NTR. The inclusion of connectivity in these models still failed to identify any positive effects of the NTR at the assemblage level. Yet, there were significant benefits to juvenile fish abundance for 5 of 7 families, and for 1 family of non-target adults. Possible explanations for the limited success of the NTR for fish assemblages include failing to account for the ecology of fish species in NTR design, the drawbacks of ‘inside−outside’ (of the NTR) experimental designs and the fact that fishing does not always impact non-target species. It is important to recognise that mangrove NTRs do not necessarily benefit fish assemblages as a whole, but that finer-scale assessments of specific families may reveal some of the proclaimed benefits of NTRs in tropical estuaries.
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Ida Slater: A Collection Researcher in a Male World at the Beginning of the 20th Century'Ida Lilian Slater (1881-1969) was one of the first women to work as a geologist in a male w·orld, and although her career was short, she made important contributions to the Early Palaeozoic of Wales and Scotland. Her main work was based on a col lection of a group of fossil scyphozoan polyps gathered not by her but by another significant woman, Elizabeth Anderson , widely known as Mrs. Robert Gray (1831-1924). The majority of this col lection is kept at the Natural History Museum (NHM), London, and the Sedgwick Museum, Cambridge. She worked in the former one for two years describing species and comparing specimens for her monograph on British conulariids. Although her work was based not only on this group, she will be remembered by her important contribution to the conulariids through collections. The NHM collection is considered the best in the world in terms of diversity and the second best in its number of specimens, while the Sedgwick Museum has a smal ler co llection that is still considered the second best in diversity and number of specimens in the United l<ingdom. Her work has been cited for more than 100 years and continues to be cited to this day by researchers on this group of fossi ls.
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Maria Ogilvie GordonA biographical dictionary entry for Maria Ogilvie Gordon
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Geodiversity Action Plans – A method to facilitate, structure, inform and record action for geodiversityGeodiversity Action Plans are used widely within the United Kingdom to inform and record action for geodiversity and geoconservation. They encompass both site-based audit and conservation with a wider perspective on geodiversity resources available in an agreed area (such as geological sites, museum collections and building stones) with ambitions to present and communicate, influence policy and practice, and to secure resources in relation to geodiversity. Geodiversity Action Plans (GAPs) are used particularly at local and company level to focus and highlight the work needed to be carried out and a as key mechanism to facilitate and support the delivery of the overarching UK Geodiversity Action Plan (UKGAP). Importantly, GAPs cross cut interests and are multidisciplinary. Although they are mainly a UK tool for geoconservation the principles and approach are easily transferred and could be duplicated in other countries.
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The contribution of women to Welsh geological research and education up to 1920The importance of Welsh geology to the development of the science of geology and the stratigraphic column is underestimated and indeed the contribution of women to this process is largely overlooked. This paper explores the scientific contribution and the role that women played to the investigation of Welsh stratigraphy. The work of Gertrude Elles, Ethel Skeat, Ethel Wood and Margaret Crosfield, the socalled Newnham quartet of palaeontologists, and the educational contribution of Dilys Davies, the first female to study geology at Newnham College, Cambridge and of Annie Greenly to the work of her husband Edward Greenly on Anglesey is discussed. Catherine Raisin also contributed work on the metamorphic rocks of Wales and her work is examined. Without their contributions, Welsh stratigraphy would not be as advanced as it is today especially in the use of graptolite identification for correlation. However, scientific research was not the only contribution and other roles such as illustrators, proof readers, field assistants and teachers will also be examined against the background of the time. The fact that there were few higher education institutions in Wales at the time admitting women to geology is a significant factor for geological research. The contribution of female researchers to this research development is largely forgotten by both researchers, educators and the general public. This paper hopes to rectify these omissions.
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Female medal and fund recipients of the Geological Society of London: a historical perspective.The Geological Society of London has historically awarded medals and funds to early career geologists and for career achievement recognition. Mid-career and outreach awards were later added as categories. This paper will concentrate on early recipients of Funds and Medal winners mainly during the 19th and 20th centuries. In the 19th century, only two women received recognition by the Geological Society for their work through early career funds (not medals): Catherine Raisin in 1893 and Jane Donald in 1898. From 1900-1919, no woman received a medal, but funds were collected by men on behalf of Gertrude Elles, Elizabeth Gray, Ethel Wood, Helen Drew, Ida Slater and Ethel Skeat. The first woman to collect her own Fund was Ethel Skeat in 1908. Pre-WWII only four women received career recognition in the form of a medal. Gertrude Elles in 1919 and Ethel Shakespear in 1920 received the Murchison Medal. No further medals were awarded to women until Maria Ogilvie Gordon in 1932 and Eleanor Mary Reid in 1936. It was not until the end of the 1990s and into the 21st century that a significant number of women received medals. It is noted that the William Smith Medal was only received by a woman in 2019 and the Dewey Medal has yet to be received by a woman. An analysis of the different medals and funds awarded to females through the Geological Society is discussed in detail with snapshots of the women who were so recognised. As we move into the 21st century we see an increase in these awards to women. The awarding of a professional Society medal or fund is an honour given to few academics, experts or publicly minded individuals. It is a public acknowledgement of an achievement, often coming with financial benefit and can be regarded as peer recognition of a significant contribution to society either through research or outreach activities. During the 19th century, awarding this recognition to a female was unusual. The Geological Society of London began its life in 1807 (Herries-Davies 2007) and since 1831, when the Wollaston Medal and Funds were first awarded, it has awarded 1423 medals and funds to date (January 2020). Of these, 110 recipients were women (7.7%), representing 5.3% of medal and 10.8% of fund winners. However, these percentages have dramatically changed over time (Fig. 1). A larger number of awards were given to women in the first 18 years of the 21st century than the previous two centuries together. The disparity between genders is shown in Figure 2, and the length of time before the first medal or fund was awarded to a female is shown in Figure 3. The only woman to have been awarded two medals is Janet Watson (1923-1985), the Lyell Medal in 1973 and the Bigsby Medal in 1965. Twelve women have received both a fund and medal: Catherine Raisin (1855-1945), Gertrude Elles (1872-1960), Ethel Wood (Dame Shakespear) (1871-1945), Eileen Mary Lind Hendriks (1888-1978), Eleanor Reid (1860–1953), Helen Muir-Wood (1895-1968) , Marjorie Chandler (1897–1983), Dorothy Hill (1907-1997), Dorothy Rayner (1912-2003), Mabel Tomlinson (1893-1978), Dianne Edwards (1942- ) and Jane Plant (1945-2016). Several of these women have individual chapters devoted to them within this volume of research and so will not be discussed in detail here. This paper will concentrate on the early years and first recipients of medal and fund awards to women, and, although mention will be made of the success of the 21st century for clarity and completion, it is not the main aim of this paper.
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Mabel Elizabeth Tomlinson and Isabel Ellie Knaggs: two overlooked early female Fellows of the Geological SocietyAbstract: The first female Fellows of the Geological Society of London were elected in May 1919. Brief biographies were documented by Burek in 2009 as part of the celebrations for the bicentenary of the Geological Society. While some of those women were well known (e.g. Gertrude Elles and Ethel Wood), others had seemingly been forgotten. In the decade since that publication, information has come to light about those we knew so little about. There are, however, still some details evading research. From 1919 until 1925, 33 women were elected FGS, including Isobel Ellie Knaggs (1922) and Mabel Tomlinson (1924). Mabel Tomlinson had two careers, and is remembered both as an extraordinary teacher and a Pleistocene geologist. She was awarded the Lyell Fund in 1937 and R.H. Worth Prize in 1961, one of only 13 women to have received two awards from the Geological Society. She inspired the educational Tomlinson–Brown Trust. Isabel Knaggs was born in South Africa and died in Australia but spent all her school, university and working years in England. She made significant contributions to crystallography, working with eminent crystallography scientists but remained a lifelong FGS. The achievements of Tomlinson and Knaggs are considerable, which makes their relative present-day obscurity rather puzzling.
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Gertrude Elles: The pioneering graptolite geologist in a woolly hat. Her career, her achievements and personal reflections of her family and colleaguesGertrude Elles gained worldwide renown for her seminal work with Ethel Wood on ‘A Monograph of British Graptolites’ which is still used today. She gained the MBE, pioneered female geological education, became the first female reader in Cambridge University and one of the first tranche of female Fellows of the Geological Society in 1919. An eccentric with a vast array of hats, PhD students and lodgers, she was a stalwart member of the Sedgwick Club and life member of the British Federation of University Women. She wrote obituaries for colleagues describing their achievements with humour and good nature. Her family describe her as ‘a fabulous woman’ with a huge range of interests including archaeology, botany and music. She related her geological and botanical knowledge in showing a nephew that plants growing along the Moine Thrust reflected change in the underlying rocks. Cambridge colleagues recall her as a ‘marvellous and well-respected figure’ who caused some amusement by her big old cluttered table from which she swept away material making room for new samples (and work for technicians). She died in 1960 in her beloved Scotland. However, her legacy survives in the classification of a group of fossils extinct for nearly 400 million years. The well documented career and achievements of Gertrude Elles (Burek 2002, 2007, 2009, 2014, Creese 1994, 2004) establish her as a great geologist who was ahead of her time and had an enduring love of the outdoors, particularly the Scottish Highlands. Her outstanding contribution to the field of palaeontology was ‘A Monograph of British Graptolites’ which she co-authored with Ethel Wood and which is still widely used today. She was also an inspirational lecturer, always remembered for her enthusiasm and as an advocate for women’s education and advancement. From several personal accounts, she was identified as an amazing, slightly eccentric person with wide ranging interests and knowledge. Her family called her G and speak of her with pride. ACCEPTED MANUSCRIPT Downloaded from http://sp.lyellcollection.org/ by guest on October 27, 2020 Cambridge colleagues called her Gertie (but not to her face!) and remember her with affection, respect and some amusement. The ‘woolly hat’ in the title refers to one of the best-known photos of her (Fig.1), and because she had a vast array of hats. The reason for this collection was her appointment in the department in Cambridge, which required women to wear hats when lecturing (Burek 2007).
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Margaret Chorley Crosfield, FGS: the very first female Q1 Fellow of the Geological SocietyIn May 1919 the first female Fellows of the Geological Society were elected and from then on attended meetings at the Society. The first person on the female fellows’ list was Margaret Chorley Crosfield. She was born in 1859 and died in 1952. She lived all her life in Reigate in Surrey. After studying and then leaving Cambridge, Margaret had sought to join the Geological Society of London for many years, in order to gain recognition of her research work, but also to attend meetings and use the library. This paper will look at her history and trace her geological achievements in both stratigraphy and palaeontology, as well as her extraordinary field notebooks that she left to the Geological Survey. She worked closely with two female geological colleagues, Mary Johnston and Ethel Skeat. Margaret Crosfield epitomizes the educated, amateur, independent woman who wanted to be recognized for her work, especially fieldwork, at a time when female contributions, especially in the field sciences, were not always acknowledged or even appreciated.
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Celebration of the Centenary of the first female Fellows: IntroductionAbstract The Geological Society of London was founded in 1807. In May 1919, the first female Fellows were elected to the Society, 112 years after its foundation. This Special Publication celebrates this centenary Eighteen papers have been gathered to highlight recent research, carried out by 24 authors. The publication also builds on stories introduced in a previous Special Publication of the Geological Society, The Role of Women in the History of Geology edited by Burek & Higgs in 2007, the first book to deal solely with this topic, and Burek (2009). It fills in some of the gaps in knowledge with detail that has only recently been uncovered, leading to more in-depth analysis and reporting. The current publication includes more examples from the 20th century, and a small number into the present century, allowing some trends to be identified. The collective work is finding connections previously undocumented and in danger of being lost forever due to the age of the interviewees. The same work also identifies several common challenges that female geoscientists faced, which are still evident in the current investigations. By building on what went before, filling gaps in knowledge and enriching the histories, interesting nuanced insights have emerged.
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Zoo-housed mammals do not avoid giving birth on weekendsThere is evidence that zoo visitor presence can influence the behavior and, in some cases, adrenal response of zoo animals, and can sometimes compromise animal welfare. In some laboratory studies, significantly more primate births have been reported on weekends, when fewer people are working there, compared with weekdays when staffing levels are at their highest. Here we investigate whether there is evidence of a “weekend effect” on births in zoo animals as a result of visitor numbers. Unlike laboratories, zoos are typically busier with visitors on weekends than on weekdays, although staffing levels remain fairly consistent across days of the week. If zoo animal parturition is sensitive to human presence, then fewer births would be expected on weekends compared with weekdays. We tested this using birth data and visitor numbers on the entrance gate from zoo records across 16 species representing artiodactyls, perissodactyls, carnivores and primates at four British zoos, to see whether there is an association between mean daily birth rates and average visitor numbers. We predict that, if there is a visitor effect, daily births should be lower on weekends than weekdays and should correlate with mean daily visitor numbers. Results showed that births for all 16 species were randomly distributed through the week, and there was no significant decline in births on weekends. We conclude that the ‘weekend effect’, if such a thing exists, does not appear to be a feature of zoo births, suggesting that elevated weekend visitor numbers are not sufficiently stressful to trigger delayed parturition.
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Margaret Chorley Crosfield, FGS: the very first female Fellow of the Geological SocietyAbstractIn May 1919 the first female Fellows of the Geological Society were elected and from then on attended meetings at the Society. The first person on the female fellows’ list was Margaret Chorley Crosfield. She was born in 1859 and died in 1952. She lived all her life in Reigate in Surrey. After studying and then leaving Cambridge, Margaret had sought to join the Geological Society of London for many years, in order to gain recognition of her research work, but also to attend meetings and use the library. This paper will look at her history and trace her geological achievements in both stratigraphy and palaeontology, as well as her extraordinary field notebooks that she left to the Geological Survey. She worked closely with two female geological colleagues, Mary Johnston and Ethel Skeat. Margaret Crosfield epitomizes the educated, amateur, independent woman who wanted to be recognized for her work, especially fieldwork, at a time when female contributions, especially in the field sciences, were not always acknowledged or even appreciated.
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The role of specific biomarkers, as predictors of post-operative complications following flexible ureterorenoscopy (FURS), for the treatment of kidney stones: a single-centre observational clinical pilot-study in 37 patientsAbstract: Background: The number of patients diagnosed and subsequently treated for kidney stones is increasing, and as such the number of post-operative complications is likely to increase. At present, little is known about the role of specific biomarkers, following flexible ureterorenoscopy (FURS) for the surgical treatment of kidney stones. The main aim of the study was to evaluate the role of kidney and infection biomarkers, in patients undergoing FURS. Methods: Included were 37 patients (24 males, 13 females), who underwent elective FURS, for the treatment of kidney stones. Venous blood samples were collected from each patient: pre-operatively, and at 30 min, 2 and 4 h post-operatively. Changes to kidney (NGAL, Cystatin-C) and infection (MPO, PCT) biomarkers was quantified by means of ELISA, Biomerieux mini-vidas and Konelab 20 analysers. Results: Four patients developed post-operative complications (3 - UTIs with urinary retention, 1 - urosepsis. NGAL concentration increased significantly following FURS (p = 0.034). Although no significant changes were seen in Cystatin C, MPO and PCT (p ≥ 0.05) some key clinical observation were noted. Limiting factors for this study were the small number of patients recruited and restriction in blood sampling beyond 4 h. Conclusions: Although not confirmative, changes seen to biomarkers such as Cystatin C, NGAL and MPO in our observational clinical pilot-study may warrant further investigation, involving larger cohorts, to fully understand the role of these biomarkers and their potential association with post-operative complications which can develop following FURS.
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Seascape genomics reveals population isolation in the reef-building honeycomb worm, Sabellaria alveolata (L.)Background: Under the threat of climate change populations can disperse, acclimatise or evolve in order to avoid fitness loss. In light of this, it is important to understand neutral gene flow patterns as a measure of dispersal potential, but also adaptive genetic variation as a measure of evolutionary potential. In order to assess genetic variation and how this relates to environment in the honeycomb worm (Sabellaria alveolata (L.)), a reef-building polychaete that supports high biodiversity, we carried out RAD sequencing using individuals from along its complete latitudinal range. Patterns of neutral population genetic structure were compared to larval dispersal as predicted by ocean circulation modelling, and outlier analyses and genotype-environment association tests were used to attempt to identify loci under selection in relation to local temperature data. Results: We genotyped 482 filtered SNPs, from 68 individuals across nine sites, 27 of which were identified as outliers using BAYESCAN and ARLEQUIN. All outlier loci were potentially under balancing selection, despite previous evidence of local adaptation in the system. Limited gene flow was observed among reef-sites (FST = 0.28 ± 0.10), in line with the low dispersal potential identified by the larval dispersal models. The North Atlantic reef emerged as a distinct population and this was linked to high local larval retention and the effect of the North Atlantic Current on dispersal. Conclusions: As an isolated population, with limited potential for natural genetic or demographic augmentation from other reefs, the North Atlantic site warrants conservation attention in order to preserve not only this species, but above all the crucial functional ecological roles that are associated with their bioconstructions. Our study highlights the utility of using seascape genomics to identify populations of conservation concern.
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Social Experience of Captive Livingstone’s Fruit Bats (Pteropus livingstonii)Social network analysis has been highlighted as a powerful tool to enhance the evidence-based management of captive-housed species through its ability to quantify the social experience of individuals. We apply this technique to explore the social structure and social roles of 50 Livingstone’s fruit bats (Pteropus livingstonii) housed at Jersey Zoo, Channel Islands, through the observation of associative, affiliative, and aggressive interactions over two data collection periods. We implement binomial mixture modelling and characteristic-based assortment quantification to describe the complexity and organisation of social networks, as well as a multiple regression quadratic assignment procedural (MRQAP) test to analyse the relationship between network types. We examine the effects of individual characteristics (i.e., sex, age, and dominance rank) on social role by fitting models to explain the magnitude of node metrics. Additionally, we utilize a quadratic assignment procedural (QAP) test to assess the temporal stability of social roles over two seasons. Our results indicate that P. livingstonii display a non-random network structure. Observed social networks are positively assorted by age, as well as dominance rank. The frequency of association between individuals correlates with a higher frequency of behavioural interactions, both affiliative and aggressive. Individual social roles remain consistent over ten months. We recommend that, to improve welfare and captive breeding success, relationships between individuals of similar ages and dominance levels should be allowed to persist in this group where possible, and separating individuals that interact frequently in an affiliative context should be avoided.
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White-faced Darter distribution is associated with coniferous forests in Great BritainAbstract 1) Understanding of dragonfly distributions is often geographically comprehensive but less so in ecological terms. 2) White-faced darter (Leucorhinnia dubia) is a lowland peatbog specialist dragonfly which has experienced population declines in Great Britain. White-faced darter are thought to rely on peat-rich pool complexes within woodland but this has not yet been empirically tested. 3) We used dragonfly recording data collected by volunteers of the British Dragonfly Society from 2005 to 2018 to model habitat preference for white-faced darter using species distribution models across Great Britain and, with a more detailed landcover dataset, specifically in the North of Scotland. 4) Across the whole of Great Britain our models used the proportion of coniferous forest within 1km as the most important predictor of habitat suitability but were not able to predict all current populations in England. 5) In the North of Scotland our models were more successful and suggest that habitats characterised by native coniferous forest and areas high potential evapotranspiration represent the most suitable habitat for white-faced darter. 6) We recommend that future white-faced darter monitoring should be expanded to include areas currently poorly surveyed but with high suitability in the North of Scotland. 7) Our results also suggest that white-faced darter management should concentrate on maintaining Sphagnum rich pool complexes and the maintenance and restoration of native forests in which these pool complexes occur.
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Open Carboniferous Limestone pavement grike microclimates in Great Britain and Ireland: understanding the present to inform the futureLimestone pavements are a distinctive and irreplaceable geodiversity feature, in which are found crevices known as grikes. These grikes provide a distinct microclimate conferring a more stable temperature, higher relative humidity, lower light intensity and lower air speed than can be found in the regional climate. This stability of microclimate has resulted in an equally distinctive community of flora and fauna, adapted to a forest floor but found in an often otherwise barren landscape. This thesis documents the long-term study of the properties of the limestone pavement grike in order to identify the extent to which the microclimate may sustain its distinctive biodiversity, to provide recommendations for future research which may lead to more effective management. Over a five-year study, recordings of temperature, relative humidity, light intensity and samples of invertebrate biodiversity were collected from five limestone pavements situated in the Yorkshire Dales and Cumbria in Great Britain, and The Burren in the Republic of Ireland. An extensive description of the grike microclimate was undertaken using the data collected to understand the extent of the microclimate stability of the grike and the conditions for variation in the grike microclimate. Further insights into the grike microclimate were gained through simulation techniques more commonly used in engineering, to explore the effects of air flowing over a grike, the light from the sun entering the grike and regression analysis to simulate the temperature within the grike in the present and projected for the future. This study has indicated that although the whole of the grike confers a degree of microclimatic stability, it is made up of a less stable upper zone and a more stable lower zone. The instability of the upper zone is hypothesised to result from the extent to which the majority of light and external air can enter the grike, whereas the stability of the lower zone may be governed by the thermal stability of the limestone surrounding it. Based on this zonation and the projections for the grike temperature, it is hypothesised that climate change will have the most substantial effects in the upper grike zone where species obligated to this area could be most heavily impacted. This study recommends a range of areas in which research may be employed so that the limestone pavement habitat may be successfully managed in Great Britain and the Republic of Ireland.
