Exploring the maintenance of plumage polymorphism in the Black Sparrowhawk

Animals often display striking variation with respect to their phenotype. Intraspecific and interspecific variation in body colour represents one of the most well studied forms of phenotypic variation. For decades evolutionary biologists have been fascinated by the mechanisms that maintain colour variation in species and traditional explanations for this diversity of colour in nature often invoke an interaction between selection for conspicuous signals and natural selection for crypsis. Colour polymorphic species have frequently been used to explore the evolutionary processes that lead to colour variation in species. Geographic variation in colour morph ratios also occurs frequently in polymorphic species and is often considered an ideal model system to examine the interplay of gene flow and local adaptation in populations. This thesis aims to explore the role and maintenance of plumage colour polymorphism in a raptor, the black sparrowhawk. The black sparrowhawk exhibits discrete colour polymorphism, with adults occurring as either white or dark morphs. Within South Africa, the species has undergone a recent range expansion, successfully colonising the Cape Peninsula in the Western Cape. As winter breeders, black sparrowhawks in South Africa now experience two contrasting climatic regimes; dry winters in their historical north-eastern range, and wet winters in the recently colonised Western Cape region. Within this newly colonised region, the dark morph occurs in greatest frequency. Across South Africa, the species displays clinal variation, with the frequency of dark morphs declining from > 75 % in the far south-west on the Cape Peninsula, to < 20 % in the north-east of the country. Two contrasting hypotheses have been proposed for the high frequency of dark morph birds in the Cape Peninsula population; (1) that colour variation is non-adaptive and is simply due to a chance founder effect and strong genetic drift and (2) this is reflective of local adaptation and that irrespective of the founding morph ratios, dark morphs have a selective advantage in this newly colonised environment with its novel winter rainfall regime. The main aims of this study were to determine the (i) ecological and evolutionary mechanisms that influence the maintenance of colour polymorphism in the species and (ii) to establish explanations for the unusually high proportion of dark morphs on the Cape Peninsula. In this thesis I have used a range of ecological and genetic approaches to explore both neutral and adaptationist explanations for the high frequency of dark morphs in my study population. Data from the mitochondrial control region was used to examine the distribution of genetic diversity in several geographic populations of black sparrowhawks across South Africa, allowing the exploration of trait divergence under neutrality. Using a phylogeographic framework, genetic variation was used to (i) quantify the extent to which population structure and gene flow may influence the observed pattern of colour morphs in the focal study population on the Cape Peninsula, and (ii) explore how selection and gene flow may interact to explain the patterns of morph frequencies in my study system. I found very low genetic differentiation between sample sites across South Africa suggesting that substantial gene flow occurs among populations, supporting the hypothesis that selection, and thus local adaptation, is the primary force maintaining colour variation on the Peninsula

Differential Haemoparasite Intensity between Black Sparrowhawk (Accipiter melanoleucus) Morphs Suggests an Adaptive Function for Polymorphism

Recent research suggests that genes coding for melanin based colouration may have pleiotropic properties, in particular conveying raised immune function. Thus adaptive function of polymorphism may be associated with parasite resistance. The black sparrowhawk Accipiter melanoleucus is a polymorphic raptor with two morphs. Over most of its range the light morph is commonest, however within the recently colonised Western Cape of South Africa the dark morph predominates. The species breeds in winter throughout South Africa, however unlike in the rest of the species' South African range, the Western Cape experiences a winter rainfall regime, where arthropod vectors which transmit haematozoan parasites may be more abundant. We hypothesise that the higher frequency of dark morph birds in this region may be due to their improved parasite resistance, which enables them to cope with higher parasite pressure. If so, we predict that dark morph black sparrowhawks would have lower parasite burdens than light morph birds. Within our population the prevalence of the two most common haematozoan parasites was high, with 72% of adults infected with Haemoproteus nisi and 59% of adults infected with Leucocytozoon toddi. We found no difference in prevalence for either parasite between adult morphs, or between chicks of different parental morphs. However, within adults infected with H. nisi, infection intensity was significantly higher in light morphs than dark morphs. This suggests that dark morphs have lower parasite loads than light morphs due to resistance rather than morph-specific habitat exploitation. Greater resistance to Haemoproteus parasites may therefore be one of the mechanisms through which dark morph black sparrowhawks have a selective advantage in this region and may explain why they are most common in our study area. In other regions, the cost to benefit ratio may be in favour of the light morph, where parasites are less abundant or virulent

The CM-Path Biobanking Sample Quality Improvement Tool : A Guide for Improving the Quality of Tissue Collections for Biomedical Research and Clinical Trials in Cancer

Funding: The NCRI's CM-Path initiative was established in 2016 with the aim of re-invigorating academic pathology. It is funded as a collaborative venture between ten of the NCRI partner organisations: Bloodwise, Breast Cancer Now, Cancer Research UK, the Chief Scientist Office (Scotland), the Department of Health and Social Care (England), Health and Care Research Wales, Health and Social Care (Northern Ireland), the Medical Research Council, Prostate Cancer UK and Tenovus Cancer Care. These organisations did not participate in study design; collection, analysis and interpretation of data; writing the report or the decision to submit the paper for publication. Acknowledgments Thanks to the following for assisting in the scoping exercise: Joanna Baxter, Cambridge Blood and Stem Cell Bank; Chris Birkett, Human Tissue Authority; Tim Brend, Breast Cancer Now Tissue Bank, University of Leeds; Brian Clark, Novo Nordisk; Emma Lawrence, UKCRC Tissue Directory and Coordination Centre; Alex MacLellan, CRUK Tissue Group, Edinburgh; Balwir Matharoo-Ball, Nottingham Health Sciences Biobank; Bill Mathieson, NHS Grampian Biorepository; Gita Mistry Children’s Cancer and Leukaemia Group Tissue Bank; Will Navaie, Health Research Authority; Rob Oliver, Salford Royal NHS Foundation Trust; Kathleen Potter, Cancer Sciences Tissue Bank, University of Southampton; Doris Rassl, Papworth Hospital NHS Foundation Trust; Jane Steele, Human Biomaterials Resource Centre, University of Birmingham; Sarah Yeats, WISH Lab, University of Southampton. Special thanks Anne Carter for her tireless work with CCB and to staff at the following biobanks who piloted the Sample Quality Improvement Tool: Greater Glasgow & Clyde Biorepository, Leeds Breast Cancer Now Tissue Bank, Leeds Multidisciplinary Research Tissue Bank and Southampton Tissue Bank.Peer reviewedPostprin

Perceptions of vulture supplementary feeding site managers and potential hidden risks to avian scavengers

Under the current African vulture crisis, supplementary feeding sites (SFS), which provide carrion resources, have become a popular conservation tool to address vulture declines. In South Africa, this practice is unregulated and the context in which SFS operate and their adherence to best management practices is currently unknown. In this study, we conducted a survey with SFS managers regarding the management of their SFS to evaluate potential conservation implications of different practices. Half of the SFS surveyed were associated with livestock farming. Overall, most managers (84%) perceived some benefit from running an SFS, largely attributed to cleaning services provided by vultures. Over half of the managers perceived no disadvantages from running SFS. We found a positive correlation between numbers of vultures seen at SFS and the amount of food provided there. Despite unintentional and intentional poisoning being identified by experts as the most critical threats to vultures in Southern Africa, only 47 and 24% of managers, respectively, listed these as potential threats to vultures, highlighting limited understanding of current vulture conservation issues. Most managers (85%) vetted carcasses for provisioning suitability based on whether they had been treated with veterinary drugs, but relatively few managers (10%) did the same for lead (Pb) contamination. Only 30% of managers considered threats to vultures when they decided on a location for their SFS. Overall, this study unveils that at many SFS, safety conditions are not met and vultures may be exposed to risks, such as the ingestion of toxic substances (e.g., Pb) or electrocution by energy infrastructure. To minimize unintended negative consequences from SFS, it will be essential to increase the interaction between SFS managers and conservation practitioners, to increase the flow of information on best management practices and enforce stringent and clear guidelines that minimize any risks to vultures.Peer reviewe

The Effects on Saturated Fat Purchases of Providing Internet Shoppers with Purchase- Specific Dietary Advice: A Randomised Trial

OBJECTIVES: The supermarket industry now services many customers through online food shopping over the Internet. The Internet shopping process offers a novel opportunity for the modification of dietary patterns. The aim of this study was to evaluate the effects on consumers' purchases of saturated fat of a fully automated computerised system that provided real-time advice tailored to the consumers' specific purchases recommending foods lower in saturated fat. DESIGN: This study was a blinded, randomised controlled trial. SETTING: The study was conducted in Sydney, New South Wales, Australia. PARTICIPANTS: The participants were consumers using a commercial online Internet shopping site between February and June 2004. INTERVENTIONS: Individuals assigned to intervention received fully automated advice that recommended specific switches from selected products higher in saturated fat to alternate similar products lower in saturated fat. Participants assigned to control received general non-specific advice about how to eat a diet lower in saturated fat. OUTCOME MEASURES: The outcome measure was the difference in saturated fat (grams per 100 g of food) in shopping baskets between the intervention and control groups. RESULTS: There were 497 randomised participants, mean age 40 y, each shopping for an average of about three people. The amount of saturated fat in the foods purchased by the intervention group was 0.66% lower (95% confidence interval 0.48–0.84, p < 0.001) than in the control group. The effects of the intervention were sustained over consecutive shopping episodes, and there was no difference in the average cost of the food bought by each group. CONCLUSIONS: Fully automated, purchase-specific dietary advice offered to customers during Internet shopping can bring about changes in food purchasing habits that are likely to have significant public health implications. Because implementation is simple to initiate and maintain, this strategy would likely be highly cost-effective

The UK Fireball Alliance (UKFAll); Combining and Integrating the Diversity of UK Camera Networks to Aim to Recover the First UK Meteorite Fall for 30 Years

No abstract available

Selective Inhibitors of Protozoan Protein N-myristoyltransferases as Starting Points for Tropical Disease Medicinal Chemistry Programs

Inhibition of N-myristoyltransferase has been validated pre-clinically as a target for the treatment of fungal and trypanosome infections, using species-specific inhibitors. In order to identify inhibitors of protozoan NMTs, we chose to screen a diverse subset of the Pfizer corporate collection against Plasmodium falciparum and Leishmania donovani NMTs. Primary screening hits against either enzyme were tested for selectivity over both human NMT isoforms (Hs1 and Hs2) and for broad-spectrum anti-protozoan activity against the NMT from Trypanosoma brucei. Analysis of the screening results has shown that structure-activity relationships (SAR) for Leishmania NMT are divergent from all other NMTs tested, a finding not predicted by sequence similarity calculations, resulting in the identification of four novel series of Leishmania-selective NMT inhibitors. We found a strong overlap between the SARs for Plasmodium NMT and both human NMTs, suggesting that achieving an appropriate selectivity profile will be more challenging. However, we did discover two novel series with selectivity for Plasmodium NMT over the other NMT orthologues in this study, and an additional two structurally distinct series with selectivity over Leishmania NMT. We believe that release of results from this study into the public domain will accelerate the discovery of NMT inhibitors to treat malaria and leishmaniasis. Our screening initiative is another example of how a tripartite partnership involving pharmaceutical industries, academic institutions and governmental/non-governmental organisations such as Medical Research Council and Wellcome Trust can stimulate research for neglected diseases

Cerebral microbleeds and intracranial haemorrhage risk in patients anticoagulated for atrial fibrillation after acute ischaemic stroke or transient ischaemic attack (CROMIS-2):a multicentre observational cohort study

Background: Cerebral microbleeds are a potential neuroimaging biomarker of cerebral small vessel diseases that are prone to intracranial bleeding. We aimed to determine whether presence of cerebral microbleeds can identify patients at high risk of symptomatic intracranial haemorrhage when anticoagulated for atrial fibrillation after recent ischaemic stroke or transient ischaemic attack. Methods: Our observational, multicentre, prospective inception cohort study recruited adults aged 18 years or older from 79 hospitals in the UK and one in the Netherlands with atrial fibrillation and recent acute ischaemic stroke or transient ischaemic attack, treated with a vitamin K antagonist or direct oral anticoagulant, and followed up for 24 months using general practitioner and patient postal questionnaires, telephone interviews, hospital visits, and National Health Service digital data on hospital admissions or death. We excluded patients if they could not undergo MRI, had a definite contraindication to anticoagulation, or had previously received therapeutic anticoagulation. The primary outcome was symptomatic intracranial haemorrhage occurring at any time before the final follow-up at 24 months. The log-rank test was used to compare rates of intracranial haemorrhage between those with and without cerebral microbleeds. We developed two prediction models using Cox regression: first, including all predictors associated with intracranial haemorrhage at the 20% level in univariable analysis; and second, including cerebral microbleed presence and HAS-BLED score. We then compared these with the HAS-BLED score alone. This study is registered with ClinicalTrials.gov, number NCT02513316. Findings: Between Aug 4, 2011, and July 31, 2015, we recruited 1490 participants of whom follow-up data were available for 1447 (97%), over a mean period of 850 days (SD 373; 3366 patient-years). The symptomatic intracranial haemorrhage rate in patients with cerebral microbleeds was 9·8 per 1000 patient-years (95% CI 4·0–20·3) compared with 2·6 per 1000 patient-years (95% CI 1·1–5·4) in those without cerebral microbleeds (adjusted hazard ratio 3·67, 95% CI 1·27–10·60). Compared with the HAS-BLED score alone (C-index 0·41, 95% CI 0·29–0·53), models including cerebral microbleeds and HAS-BLED (0·66, 0·53–0·80) and cerebral microbleeds, diabetes, anticoagulant type, and HAS-BLED (0·74, 0·60–0·88) predicted symptomatic intracranial haemorrhage significantly better (difference in C-index 0·25, 95% CI 0·07–0·43, p=0·0065; and 0·33, 0·14–0·51, p=0·00059, respectively). Interpretation: In patients with atrial fibrillation anticoagulated after recent ischaemic stroke or transient ischaemic attack, cerebral microbleed presence is independently associated with symptomatic intracranial haemorrhage risk and could be used to inform anticoagulation decisions. Large-scale collaborative observational cohort analyses are needed to refine and validate intracranial haemorrhage risk scores incorporating cerebral microbleeds to identify patients at risk of net harm from oral anticoagulation. Funding: The Stroke Association and the British Heart Foundation