• Patterns in island endemic forest-dependent bird research: the Caribbean as a case-study

      Devenish-Nelson, Eleanor S.; orcid: 0000-0002-9029-4772; email: ellie.devenish@ed.ac.uk; Weidemann, Douglas; Townsend, Jason; Nelson, Howard P. (Springer Netherlands, 2019-05-04)
      Abstract: Unequal patterns in research effort can result in inaccurate assessments of species extinction risk or ineffective management. A group of notable conservation concern are tropical island endemic birds, many of which are also forest-dependent, which increases their vulnerability to extinction. Yet, island bird species have received limited research attention compared to their continental congeners, despite this taxon being globally regarded as well-studied. We used the insular Caribbean, a globally important endemism hotspot with high rates of deforestation, to explore research bias of island and regional endemic forest-dependent birds. A review of the published literature (n = 992) found no significant increase in the number of studies over the search period. Research effort was significantly higher among species with threatened status, long generation time, wide habitat breadth and low to intermediate elevational distributions. Among family groups, the Psittacidae received the highest research effort, while the Cuculidae were the most underrepresented family (30-fold higher and six-fold less than expected, respectively). We found geographic biases in effort, with Jamaica having six-fold less and Puerto Rico eight times more research than expected for their level of endemism. These patterns likely reflect individual interests and limited capacity and funding, typical of Small Island Developing States. With over 50% of species in this review having declining population trends, we recommend prioritizing research that emphasises conservation- and management-relevant data across underrepresented families and islands, by fostering greater collaboration between researchers, practitioners and the existing local amateur ornithological community.
    • Patterns of behaviour, group structure and reproductive status predict levels of glucocorticoid metabolites in zoo-housed ring-tailed lemurs, Lemur catta.

      Smith, Tessa E.; McCusker, Cara; Stevens, Jeroen M. G.; Elwood, Robert W.; University of Chester; Queens University of Belfast; Centre for Research and Conservation, Royal Zoological Society of Antwerp, Belguim (Karger Publishing, 2016-01-30)
      In ring-tailed lemurs, Lemur catta, the factors modulating hypothalamic-pituitary-adrenal (HPA) activity differ between wild and semi-free-ranging populations. Here we assess factors modulating HPA activity in ring-tailed lemurs housed in a third environment: the zoo. First we validate an enzyme immunoassay to quantify levels of glucocorticoid (GC) metabolites in the faeces of L. catta. We determine the nature of the female-female dominance hierarchies within each group by computing David’s scores and examining these in relation to faecal GC (fGC). Relationships between female age and fGC are assessed to evaluate potential age-related confounds. The associations between fGC, numbers of males in a group and reproductive status are explored. Finally, we investigate the value of 7 behaviours in predicting levels of fGC. The study revealed stable linear dominance hierarchies in females within each group. The number of males in a social group together with reproductive status, but not age, influenced fGC. The 7 behavioural variables accounted for 68% of the variance in fGC. The amounts of time an animal spent locomoting and in the inside enclosure were both negative predictors of fGC. The study highlights the flexibility and adaptability of the HPA system in ring-tailed lemurs.
    • Pavement pleasures

      Burek, Cynthia V.; Deacon, Joanna; University College Chester (English Nature, 1998-06)
      This journal article discusses limestone pavements in north Wales.
    • A pelagic thresher shark (Alopias pelagicus) gives birth at a cleaning station in the Philippines

      Oliver, Simon P.; Bicskos Kaszo, Attila E.; University of Chester; The Thresher Shark Research and Conservation Project (Springer, 2014-12-23)
      This article discusses photographic evidence captured on April 4, 2013, as the first record of a thresher shark giving birth.
    • Pemphigus is associated with KIR3DL2 expression levels and provides evidence that KIR3DL2 may bind HLA-A3 and A11 in vivo.

      Augusto, Danillo G.; O'Connor, Geraldine M.; Lobo-Alves, Sara C.; Bass, Sara; Martin, Maureen P.; Carrington, Mary; McVicar, Daniel W.; Petzl-Erler, Maria L.; Departamento de Genética, Universidade Federal do Paraná, Curitiba, PR, Brazil; Ragon Institute of MGH, MIT and Harvard, Boston, MA, USA; Leidos Biomedical Research, Cancer and Inflammation Program, Laboratory for Experimental Immunology, Frederick National Laboratory for Cancer Research, Frederick, MD, USA; Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, Frederick, MD, USA. (Wiley, 2015-05-06)
      Although HLA-A3 and A11 have been reported to be ligands for KIR3DL2, evidence for any in vivo relevance of this interaction is still missing. To explore the functional importance of KIR3DL2 allelic variation, we analyzed the autoimmune disease pemphigus foliaceus, previously associated (lower risk) with activating KIR genes. KIR3DL2*001 was increased in patients (odds ratio (OR) = 2.04; p = 0.007). The risk was higher for the presence of both KIR3DL2*001 and HLA-A3 or A11 (OR = 3.76, p = 0.013), providing the first evidence that HLA-A3 and A11 may interact with KIR3DL2 in vivo. The nonsynonymous single nucleotide polymorphism 1190T (rs3745902) was associated with protection (OR = 0.52, p = 0.018). This SNP results in a threonine-to-methionine substitution. Individuals who have methionine in this position exhibit a lower percentage of KIR3DL2-positive natural killer (NK) cells and also lower intensity of KIR3DL2 on expressing natural killer cells; additionally, we show that the expression of KIR3DL2 is independent of other killer cell immunoglobulin-like receptors. Pemphigus foliaceus is a very unique complex disease strongly associated with immune-related genes. It is the only autoimmune disease known to be endemic, showing a strong correlation with environmental factors. Our data demonstrate that this relatively unknown autoimmune disease may facilitate understanding of the molecular mechanisms of KIR3DL2 ligand recognition.
    • Peptide-Dependent Recognition of HLA-B*57:01 by KIR3DS1

      O'Connor, Geraldine M.; Vivian, Julian P.; Gostick, Emma; Pymm, Phillip; Lafont, Bernard A.; Price, David A.; Rossjohn, Jamie; Brooks, Andrew G.; McVicar, Daniel W.; Cancer and Inflammation Program, Center for Cancer Research, National Cancer Institute, Frederick, Maryland, USA. Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria, Australia Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia. Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, Wales, United Kingdom. Non-Human Primate Immunogenetics and Cellular Immunology Unit, Laboratory of Molecular Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA. Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, Wales, United Kingdom Human Immunology Section, Vaccine Research Center, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland, USA. Department of Biochemistry and Molecular Biology, School of Biomedical Sciences, Monash University, Clayton, Victoria, Australia Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, Victoria, Australia Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff, Wales, United Kingdom. Department of Microbiology and Immunology, University of Melbourne, Parkville, Victoria, Australia. (American Society for Microbiology, 2015-04-21)
      Killer cell immunoglobulin-like receptors (KIRs) play an important role in the activation of natural killer (NK) cells, which in turn contribute to the effective immune control of many viral infections. In the context of HIV infection, the closely related KIR3DL1 and KIR3DS1 molecules, in particular, have been associated with disease outcome. Inhibitory signals via KIR3DL1 are disrupted by downregulation of HLA class I ligands on the infected cell surface and can also be impacted by changes in the presented peptide repertoire. In contrast, the activatory ligands for KIR3DS1 remain obscure. We used a structure-driven approach to define the characteristics of HLA class I-restricted peptides that interact with KIR3DL1 and KIR3DS1. In the case of HLAB*57:01, we used this knowledge to identify bona fide HIV-derived peptide epitopes with similar properties. Two such peptides facilitated productive interactions between HLA-B*57:01 and KIR3DS1. These data reveal the presence of KIR3DS1 ligands within the HIV-specific peptide repertoire presented by a protective HLA class I allotype, thereby enhancing our mechanistic understanding of the processes that enable NK cells to impact disease outcome.
    • Personality dimensions and their behavioral correlates in wild virunga mountain gorillas (Gorilla beringei beringei)

      Eckardt, Winnie; Steklis, Dieter H.; Steklis, Netzin G.; Fletcher, Alison W.; Stoinski, Tara S.; Weiss, Alexander; University of Chester & The Dian Fossey Gorilla Fund International ; University of Arizona ; University of Arizona ; University of Chester ; Zoo Atlanta & The Dian Fossey Gorilla Fund International ; University of Edinburgh & Scottish Primate Research Group. (Americal Psychological Association, 2014-12-22)
      Studies of animal personality improve our understanding of individual variation in measures of life-history and fitness, such as health and reproductive success. Using a 54 trait personality questionnaire developed for studying great apes and other nonhuman primates, we obtained ratings on 116 wild mountain gorillas (Gorilla beringei beringei) monitored by the Dian Fossey Gorilla Fund’s Karisoke Research Center in Rwanda. There were eight raters who each had more than 1.5 years of working experience with the subjects. Principal component analyses identified four personality dimensions with high inter-rater reliabilities --- Dominance, Openness, Sociability, and Proto-Agreeableness --- that reflected personality features unique to gorillas and personality features shared with other hominoids. We next examined the associations of these dimensions with independently collected behavioral measures derived from long-term records. Predicted correlations were found between the personality dimensions and corresponding behaviors. For example, Dominance, Openness, Sociability, and Proto-Agreeableness were related to gorilla dominance strength, time spent playing, rates of approaches and rates of interventions in intra-group conflicts, respectively. These findings enrich the comparative-evolutionary study of personality and provide insights into how species differences in personality are related to ecology, social systems, and life history.
    • Personality in the cockroach Diploptera punctata: Evidence for stability across developmental stages despite age effects on boldness

      Stanley, Christina R.; Mettke-Hofmann, Claudia; Preziosi, Richard F.; University of Chester; University of Manchester; Liverpool John Moores University; Manchester Metropolitan University (PLOS, 2017-05-10)
      Despite a recent surge in the popularity of animal personality studies and their wide-ranging associations with various aspects of behavioural ecology, our understanding of the development of personality over ontogeny remains poorly understood. Stability over time is a central tenet of personality; ecological pressures experienced by an individual at different life stages may, however, vary considerably, which may have a significant effect on behavioural traits. Invertebrates often go through numerous discrete developmental stages and therefore provide a useful model for such research. Here we test for both differential consistency and age effects upon behavioural traits in the gregarious cockroach Diploptera punctata by testing the same behavioural traits in both juveniles and adults. In our sample, we find consistency in boldness, exploration and sociality within adults whilst only boldness was consistent in juveniles. Both boldness and exploration measures, representative of risk-taking behaviour, show significant consistency across discrete juvenile and adult stages. Age effects are, however, apparent in our data; juveniles are significantly bolder than adults, most likely due to differences in the ecological requirements of these life stages. Size also affects risk-taking behaviour since smaller adults are both bolder and more highly explorative. Whilst a behavioural syndrome linking boldness and exploration is evident in nymphs, this disappears by the adult stage, where links between other behavioural traits become apparent. Our results therefore indicate that differential consistency in personality can be maintained across life stages despite age effects on its magnitude, with links between some personality traits changing over ontogeny, demonstrating plasticity in behavioural syndromes.
    • Physiological and behavioural measures of stress in domestic horses

      Young, Tamsin (University of Liverpool (Chester College of Higher Education), 2011-09)
      The welfare of domestic horses has been scrutinised by the scientific community in recent years. Traditional riding and stable management practices have been recognised to be at odds with the physical and behavioural adaptations of the horse. There is, therefore, a growing need to understand how modern horse management can impact on horse welfare. The first study in this thesis assessed the impact of common management practices on physiological stress in the horse. Faecal cortisol was higher in horses that were stabled and exercised, than turned out to grass with no exercise. The effect of exercise alone was also seen to increase levels of salivary cortisol. No change was seen in cortisol following short-term routine husbandry procedures such as exposure to the sound of electric coat clippers, but it was suggested that this required further investigation. The study confirmed exercise increased stress as reflected by cortisol concentration, and indicated that individual stabling may also contribute to elevated stress. The study recommended that horses may benefit from periods of rest and turn out to grass, to reduce stress levels and improve welfare. The measurement of stress for the purpose of welfare assessment is, however, best carried out using an integration of both physiological and behavioural measures. Behaviour scores offer non-invasive, quick and easy methods of assessing stress in domestic animals, but have typically been developed using only behavioural assessment of the stress response. In the second study a scale of behavioural indicators of stress was developed using behavioural and physiological measures for the purpose of assessing stress in stabled domestic horses. Principal component analysis of behavioural reactions and changes in salivary cortisol concentration in response to routine husbandry procedures, revealed three meaningful components that were used as the basis to the stress scale. Behavioural reactions to the husbandry procedures were further analysed by a panel of equestrian professionals using free choice profiling, and results were added to the appropriate components. The final scale comprised of four levels of stress (no stress, low, iii medium and high stress), and each category was further sub-divided into behaviour scores (BS). The scores represented accumulating levels of behavioural indicators of stress within each stress level, and provided indices of physiological stress. The scale offers an easy to use method of welfare assessment in horses, and reduces the need for additional physiological measures to be taken. The scale represented a novel approach to measuring stress, and was used in the final study to measure stress in horses stabled individually, group housed, and in horses moved from stabling to group housing. The effectiveness of the scale at measuring stress, was compared to the effectiveness of measures of heart rate variability (HRV) and faecal cortisol at measuring stress in the same horses. Lower levels of stress were recorded in group housed horses as measured by the BS, but measures of HRV and faecal cortisol showed no difference between those stabled or group housed. Stress levels were unaffected by the move to group housing, but BS declined significantly over the three weeks that the horses remained group housed. The physiological measures did not, however, reflect such a decrease in stress. Stress levels were also compared between horses housed in both environments whilst waiting to be fed. Group housed horses had lower stress levels as measured by the BS. Results provided by the BS were supported by relevant literature, and the scale appeared to be more sensitive than the physiological measures which did not yield significant results with the small sample sizes used in the study. The research confirmed short-term management practices horses are typically exposed to daily, can elevate their stress levels. Further research into which practices put horse welfare at a particular risk, and thus require modification or need to be avoided where possible, is necessary. The findings also suggest horse-owners may need to pay more attention to their horse’s stress levels, to avoid repeated or on-going stress that can jeopardise health and welfare. The scale of behavioural indicators of stress would provide a suitable method by which stress could be monitored and thus become a part of horse management.
    • Physiological stress in the Eurasian badger (Meles meles): Effects of host,

      George, Shelia C.; Smith, Tessa E.; Mac Cana, Pól S. S.; Coleman, Robert C.; Montgomery, William I.; Queens University of Belfast, UK; University of Chester, UK (Elsevier, 2014-03-04)
      A method for monitoring hypothalamic–pituitary–adrenal (HPA) responses of the Eurasian badger (Meles meles) to stressors was validated by measuring cortisol excretion in serum and faeces. Serum and faecal samples were collected under anaesthesia from live-captured, wild badgers and fresh faeces was collected from latrines at 15 social groups in County Down, Northern Ireland. Variation in levels of cortisol in wild badgers was investigated relative to disease status, season, age, sex, body mass, body condition and reproductive status and environmental factors that might influence stress. Faecal cortisol levels were significantly higher in animals testing culture-positive for Mycobacterium bovis. Prolonged elevation of cortisol can suppress immune function, which may have implications for disease transmission. There was a strong seasonal pattern in both serum cortisol, peaking in spring and faecal cortisol, peaking in summer. Cortisol levels were also higher in adults with poor body condition and low body mass. Faecal samples collected from latrines in grassland groups had significantly higher cortisol than those collected from woodland groups, possibly as a result of greater exposure to sources of environmental stress. This study is the first to investigate factors influencing physiological stress in badgers and indicates that serological and faecal excretion are valid indices of the HPA response to a range of stressors.
    • A Pilot Study to Evaluate Haemostatic Function, following Shock Wave Lithotripsy (SWL) for the Treatment of Solitary Kidney Stones

      Hughes, Stephen F.; Thomas-Wright, Samantha J.; Banwell, Joseph; Williams, Rachel; Moyes, Alyson J.; Mushtaq, Sohail; Abdulmajed, Mohamed; Shergill, Iqbal; University of Chester; BCUHB Wrexham Maelor Hospital (Public Library of Science, 2015-05-04)
      Purpose: The number of patients undergoing shock wave lithotripsy (SWL) in the UK for solitary unilateral kidney stones is increasing annually. The development of postoperative complications such as haematuria and sepsis following SWL is likely to increase. Comparing a range of biological markers with the aim of monitoring or predicting postoperative complications following SWL has not been extensively researched. The main purpose of this pilot-study was to test the hypothesis that SWL results in changes to haemostatic function. Subsequently, this pilot-study would form a sound basis to undertake future investigations involving larger cohorts. Methods: Twelve patients undergoing SWL for solitary unilateral kidney stones were recruited. From patients (8 male and 4 females) aged between 31–72 years (median—43 years), venous blood samples were collected pre-operatively (baseline), at 30, 120 and 240 minutes postoperatively. Specific haemostatic biomarkers [platelet counts, prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, D-dimer, von Willebrand Factor (vWF), sE-selectin and plasma viscosity (PV)] were measured. Results: Platelet counts and fibrinogen concentration were significantly decreased following SWL (p = 0.027 and p = 0.014 respectively), while D-dimer and vWF levels significantly increased following SWL (p = 0.019 and p = 0.001 respectively). PT, APTT, sE-selectin and PV parameters were not significantly changed following SWL (p>0.05). Conclusions: Changes to specific biomarkers such as plasma fibrinogen and vWF suggest that these represent a more clinically relevant assessment of the extent of haemostatic involvement following SWL. Analysis of such markers, in the future, may potentially provide valuable data on “normal” response after lithotripsy, and could be expanded to identify or predict those patients at risk of coagulopathy following SWL. The validation and reliability will be assessed through the assessment of larger cohorts.
    • Platelet-derived growth factor stimulates osteoprotegerin production in osteoblastic cells

      McCarthy, Helen S.; Williams, John H. H.; Davie, Michael W. J.; Marshall, Michael J.; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Trust in Oswestry / University of Chester ; University of Chester ; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Trust in Oswestry ; Charles Salt Centre, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Trust in Oswestry (Wiley, 2008-11-20)
      This article discusses how osteoprotegerin (OPG) production by osteoblastic cells was stimulated by platelet-derived growth factor (PDGF) in two human osteosarcoma cell lines (MG63, Saos-2), a mouse pre-osteoblastic cell line (MC3T3-E1) and human bone marrow stromal cells (hMSC) by 152%, 197%, 113% and 45% respectively over 24 h. OPG was measured in the cell culture medium by immunoassay. PDGF isoforms AA, BB and AB show similar stimulation of OPG production. Message for OPG was also increased similarly to the increased secretion into the culture medium. Using specific inhibitors of cell signalling the authors demonstrate that PDGF acts through the PDGF receptor, PKC, PI3K, ERK and P38 and not via NF-kB or JNK. The importance of PDGF in fracture healing suggests a role for OPG production in countering bone resorption during the early phase of this process.
    • Predicting the potential distribution of the Endangered huemul deer Hippocamelus bisulcus in North Patagonia

      Quevedo, Paloma; von Hardenberg, Achaz; Pastore, Hernan; Alvarez, Jose; Corti, Paulo; Ernst-Moritz-Arndt Universität, Greifswald, Germany; University of Chester; Administración de Parques Nacionales, Bariloche, Argentina;Corporación Nacional Forestal, Chile, Universidad Austral de Chile (2016-02-05)
      Habitat loss is one of the main threats to wildlife, particularly large mammals. Estimating the potential distribution of threatened species to guide surveys and conservation is crucial, primarily because such species tend to exist in small fragmented populations. The Endangered huemul deer Hippocamelus bisulcus is endemic to the southern Andes of Chile and Argentina. Although the species occurs in the Valdivian Ecoregion, a hotspot for biodiversity, we have no information on its occupancy and potential distribution in this region. We built and compared species distribution models for huemul using the maximum entropy approach, using 258 presence records and sets of bioclimatic and geographical variables as predictors, with the objective of assessing the potential distribution of the species in the Valdivian Ecoregion. Annual temperature range and summer precipitation were the predictive variables with the greatest influence in the best-fitting model. Approximately 12,360 km2 of the study area was identified as suitable habitat for the huemul, of which 30% is included in the national protected area systems of Chile and Argentina. The map of potential distribution produced by our model will facilitate prioritization of future survey efforts in other remote and unexplored areas in which huemul have not been recorded since the 1980s, but where there is a high probability of their occurrence.
    • Preliminary study of heat shock protein 70 gene expression and serum levels in newly diagnosed type 1 and type 2 diabetes

      Hunter-Lavin, Claire; Stanaway, Stephen; Bowen-Jones, David; Jones, I. R.; Loenard, M.; Clooney, K.; Williams, John H. H.; University College Chester (Hunter-Lavin) (Williams) (American Diabetes Association, 2004)
    • Preparation of Primary Rat Hepatocyte Spheroids Utilizing the Liquid-Overlay Technique.

      Kyffin, Jonathan A; Cox, Christopher R; Leedale, Joseph; Colley, Helen E; Murdoch, Craig; Mistry, Pratibha; Webb, Steven D; Sharma, Parveen (2019-09)
      Herein, we describe a protocol for the preparation and analysis of primary isolated rat hepatocytes in a 3D cell culture format described as spheroids. The hepatocyte cells spontaneously self-aggregate into spheroids without the need for synthetic extracellular matrices or hydrogels. Primary rat hepatocytes (PRHs) are a readily available source of primary differentiated liver cells and therefore conserve many of the required liver-specific functional markers, and elicit the natural in vivo phenotype when compared with common hepatic cells lines. We describe the liquid-overlay technique which provides an ultra-low attachment surface on which PRHs can be cultured as spheroids. © 2019 The Authors. Basic Protocol 1: Preparation of agarose-coated plates Basic Protocol 2: Primary rat hepatocyte isolation procedure Basic Protocol 3: Primary rat hepatocyte spheroid culture Basic Protocol 4: Immunofluorescent analysis of PRH spheroids. [Abstract copyright: © 2019 The Authors.]
    • Production of DNA aptamers with specificity for bacterial food pathogens

      Bonwick, Graham A.; Drasbek, Mette R.; Young, Niall; Smith, Christopher; McDowall, Ian; Kärkkäinen, Riikka M. (University of Chester, 2012-09)
      Aptamers are biomolecular ligands composed of nucleic acids. They can be selected to bind specifically to a range of target molecules and subsequently exploited in a fashion analogous to more traditional biomolecules such as antibodies. In this study a method for selecting new aptamers which specifically bind whole live bacterial cells is described. A non-pathogenic strain of Escherichia coli K12 was used to develop the method. A DNA library containing 100 bases long random nucleotide sequences was produced and the aptamer selection process was repeated nine times. An enzyme-linked technique was first used to detect bound aptamers thereafter fluorimetry and fluorescence microscopy methods were used for the detection. The aptamers were cloned and sequenced and the cloned aptamers produced with fluorescent labels. The E. coli K12-binding aptamers were used to demonstrate the detection of the bacterial cells in a complex food matrix, namely probiotic yogurt, by using fluorescence based detection method. The aptamer selection method with some modifications was also used to select aptamers with specificity for the food pathogens E. coli O157, Listeria monocytogenes, L. innocua, S. typhimurium and S. enteritidis. The aptamers against E. coli O157 and S. typhimurium were cloned and the sequences and the binding properties of these aptamers were analysed. The use of E. coli K12 as a target organism and the aptamer sequences presented in this study, have not previously been published in scientific literature. This is also the first report where the aptamers have been used in detection of live bacterial cells in yogurt.
    • Public health and nutrition

      Ellahi, Basma; University of Chester (SAGE, 2008-11-20)
      This book chapter discusses public health nutrition and its promotion of good health.
    • A quantified ethogram for oviposition in triturus newts: Description and comparison of T. helveticus and T. vulgaris

      Norris, Karen M.; Hosie, Charlotte A.; University of Chester (Ethologische Gesellschaft e.V., 2005-03-25)
      Female newts of the genus Triturus deposit and wrap their eggs individually in the submerged leaves of aquatic macrophytes. Although this behaviour has previously been described, the different elements of the oviposition process have not been fully characterized nor any attempt made to quantify the behavioural elements. The study examined the oviposition behaviour of the two similarly sized species, Triturus helveticus and T. vulgaris on a standardized substrate macrophyte, Rorippa nasturtium–aquaticum. Continuous focal sampling was used to develop a baseline of discrete behavioural elements enabling quantification and comparison of oviposition behaviour between the two species. The results showed that the same pattern of elements was followed for each egg laid and the same key elements of the process were present in each newt species. Although these are broadly similar in size, there were striking differences in certain aspects of the oviposition sequence between the two species. Key findings were that leaf sniffing and leaf flexing and a measure of the duration of ovipositing were all significantly greater in females of T. helveticus and females of T. vulgaris laid significantly more eggs than those of T. helveticus in a standard observation period. The work presented here defines a baseline ethogram and shows how it can be used to reveal quantifiable differences in closely related species. This demonstrates its value in furthering our understanding of oviposition – a key aspect of female behaviour currently understudied in Triturus behavioural ecology, despite its intrinsic interest and value in understanding recruitment and maintenance of populations.
    • Quantifying measurement error

      Lewis, Stephen J.; Chester College of Higher Education (Oxbow Books (for the Osteoarchaeological Research Group), 1999-12-01)
      It is important for workers to have some estimate of the degree of error evident when measuring objects. Although many use their own "rule-of-thumb" to give them the personal satisfaction that they are working accurately, measures of error, or conversely reliability, are rarely given in the lierature. Some simple, useful equations are given that may be used privately or when reporting metrical work.
    • Questioning the role of Darwinian medicine

      Lewis, Stephen J.; Chester College of Higher Education (2001-09)
      Darwinian medicine as a distinct scientific discipline can be traced to George Williams' and Randolph Nesse's paper 'The Dawn of Darwinian Medicine' (Q Rev. Biol. 66: 1-22, 1991). Ten years on, at what is still the dawn of a new millennium, it is timely to review the current state of Darwinian medicine and to assess some of its still latent potentialities. Nesse remains the main protagonist of a Darwinian approach to medicine. Important work by others has appeared but his and Williams' 'Evolution and Healing' (Weidenfeld and Nicolson, 1995)†, although written for the popular press, remains the primary text of the whole discipline. Distinct lines of academic interest and inquiry are, however, emerging within Darwinian medicine and it has found inclusion in a number of undergraduate curricula. Sufficient interest exists to suggest that it will survive as a discipline. But as a discipline, Darwinian medicine needs more than a single protagonist – it needs serious critical attention. It is important, therefore, to ask in what form the discipline is to persist and into what new areas it might go. Fundamental to such questions is the relationship between Darwinian medicine (as a scientific discipline) and Western clinical medicine (as a profession). It is suggested that, rather than try to gain direct acceptance by the medical profession, Darwinian medicine might seek to establish itself more firmly within the academic disciplines of evolutionary and human biology. It is suggested that it give special attention to identifying and making its own distinctive voice heard as a biological science of health and disease distinct from medicine – a voice that clinical medicine, drawing as ever from allied sciences, cannot then afford to ignore. To this end, the question of what might be the “zeroth law” of Darwinian medicine is posited.