Mate Guarding Conflict, Extra-Pair Courtship And Signalling in the Harlequin Duck, Histrionicus Histrionicus

Behaviour ◽  
2004 ◽  
Vol 141 (8) ◽  
pp. 1061-1078 ◽  
Author(s):  
Ian Inglis ◽  
John Lazarus ◽  
Rebecca Torrance
Keyword(s):  
Observational Studies ◽  
Reproductive Strategies ◽  
Mate Guarding ◽  
The Other ◽  
Single Model ◽  
Parallel Increase ◽  
Relative Proximity ◽  
Socially Monogamous ◽  
Mate Switching ◽  
Use Of Models

AbstractSocially monogamous birds pursuing extra-pair reproductive strategies may be in conflict, both sexes seeking new mates or copulations outside the pair, while simultaneously attempting to prevent infidelity by the partner. Intra-pair conflicts are augmented by inter-pair conflicts when pairs meet, when all four individuals may be sexually attracted to one member of the other pair while seeking to prevent their mate from copulating, or deserting, with the other. We studied the dynamics, signalling and resolution of these conflicts in a field experiment with the harlequin duck, recording responses to single model birds of both sexes, and to model pairs. Both sexes mate guarded by placing themselves between the mate and a model competitor, and by signalling with the head nod display. Females were closer to model pairs than their mates. Female mate guarding responded adaptively to infidelity risk, increasing to models of paired females, single females and single females inviting copulation, respectively. Males head nodded to signal the goal of (extra-pair) copulation, pairing or mate switching. Courtship by unpaired males increased to models of paired females, single females and single females inviting copulation, respectively. Paired males courted these models equally, perhaps inhibited by the parallel increase in mate guarding of their mates. Males signalled mate guarding using the head nod more than females, but this predicted difference in mate guarding was not shown for the measure of relative proximity to the models. In spite of male extra-pair courtship the harlequin is strictly monogamous, due to female fidelity and close mate guarding. The use of models revealed mate guarding by females, and failed extra-pair reproductive attempts by males, neither of which were apparent from observational studies alone.

scholarly journals Consistency of causal claims in observational studies: a review of papers published in a general medical journal

BMJ Open ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. e043339
Author(s):  
Camila Olarte Parra ◽  
Lorenzo Bertizzolo ◽  
Sara Schroter ◽  
Agnès Dechartres ◽  
Els Goetghebeur
Keyword(s):  
Medical Journal ◽  
Observational Studies ◽  
The Other ◽  
Research Papers ◽  
General Medical Journal ◽  
Outcome Relationship ◽  
Causal Statement ◽  
Data Source ◽  
Published Research ◽  
Causal Language

ObjectiveTo evaluate the consistency of causal statements in observational studies published in The BMJ.DesignReview of observational studies published in a general medical journal.Data sourceCohort and other longitudinal studies describing an exposure-outcome relationship published in The BMJ in 2018. We also had access to the submitted papers and reviewer reports.Main outcome measuresProportion of published research papers with ‘inconsistent’ use of causal language. Papers where language was consistently causal or non-causal were classified as ‘consistently causal’ or ‘consistently not causal’, respectively. For the ‘inconsistent’ papers, we then compared the published and submitted version.ResultsOf 151 published research papers, 60 described eligible studies. Of these 60, we classified the causal language used as ‘consistently causal’ (48%), ‘inconsistent’ (20%) and ‘consistently not causal’(32%). Eleven out of 12 (92%) of the ‘inconsistent’ papers were already inconsistent on submission. The inconsistencies found in both submitted and published versions were mainly due to mismatches between objectives and conclusions. One section might be carefully phrased in terms of association while the other presented causal language. When identifying only an association, some authors jumped to recommending acting on the findings as if motivated by the evidence presented.ConclusionFurther guidance is necessary for authors on what constitutes a causal statement and how to justify or discuss assumptions involved. Based on screening these papers, we provide a list of expressions beyond the obvious ‘cause’ word which may inspire a useful more comprehensive compendium on causal language.

scholarly journals Symptom shift in 200 patients with H63D syndrome associated with abnormal TCS findings in substantia nigra

2021 ◽  
Author(s):  
Dr. Carolina Diamandis ◽  
David Seideman ◽  
Jacob S Adams ◽  
Riku Honda ◽  
Marianne Kaufmann ◽  
...  
Keyword(s):  
Statistical Analysis ◽  
Substantia Nigra ◽  
Patient Population ◽  
Inverse Correlation ◽  
Transcranial Sonography ◽  
The Other ◽  
Significant Finding ◽  
Other Hand ◽  
Parallel Increase ◽  
The One

In a study on the prevention of injury in patients with H63D syndrome and cataplexy, statistical analysis revealed an unexpected but clinically highly significant finding. Apparently, in this patient population, an inverse correlation exists between the severity of tic symptomatology on the one hand and narcolepsy with cataplexy on the other hand, as well as a parallel increase in the typical signs of degeneration observed in transcranial sonography of the substantia nigra. This finding has clinically far-reaching implications.

Across the River

2019 ◽  
pp. 13-40
Author(s):  
Cristina I. Tica
Keyword(s):  
Daily Life ◽  
Skeletal Remains ◽  
The Other ◽  
Danube River ◽  
Traumatic Injuries ◽  
The Third ◽  
The North ◽  
Relative Proximity ◽  
Frontier Studies ◽  
Roman Province

The author seeks to contribute to the field of frontier studies with bioarchaeological data, in the hopes of understanding how living in relative proximity, but under different sociopolitical organizations, may affect health. The goal of this research is to examine differences in overall health between two groups that have been characterized in the literature as “Romans” and “barbarians.” The research uses skeletal remains to address how the daily life of people under Roman-Byzantine control compared to that of their neighbors, the “barbarians” to the north. Comparing two contemporaneous populations from the territory of modern Romania—and dating from the third to the sixth centuries CE—the study examines health status and traumatic injuries. One collection comes from the territory under Roman-Byzantine control, the site of Ibida (Slava Rusă) from the Roman province of Scythia Minor, and the other originates from the Târgşor site, located to the north of the Danube frontier, in what was considered the “barbaricum.” Separated by a definite frontier, the Danube River, meant to (at least ideologically) segregate them to their divided worlds, these populations might have been more interconnected than the carefully promulgated imperial doctrine would have us believe.

Evaluation of the Impacts of Chemotherapeutics on Odontogenesis Process: Findings from a Systematic Review

2019 ◽  
Vol 36 (03) ◽  
pp. 210-218
Author(s):  
Camila Valente Smith ◽  
Grazyelle Sebrenski da Silva ◽  
Felipe Rodolfo Pereira da Silva ◽  
José Fernando Marques Barcellos ◽  
Silvânia da Conceição Furtado
Keyword(s):  
Systematic Review ◽  
Experimental Animal ◽  
Observational Studies ◽  
Animal Studies ◽  
Direct Analysis ◽  
The Other ◽  
Cochrane Library ◽  
Oncology Patient ◽  
Therapeutic Protocol ◽  
The Individual

AbstractThis study aimed to examine and recognize the impacts of antinoplastic chemotherapeutics on the development of dental germ, employing a systematic review. A retrieving in the literature was carried out, using several medical and scientifical databases (ClinicalKey, Cochrane Library, Google Scholar, MedLine, PubMed, and ScienceDirect), by two investigators separately. In the end of this systematic search, eight articles met the required criteria for inclusion and, therefore, composed the results. Among these, four articles are about observational studies in humans, and the other four about experimental animal studies. In both cases and species, anomalies such as microdontia, hypodontia/agenesia, and root shortening were observed. The severity and frequency varied according to the nature of the chemotherapeutics applied as well as the administered dosage and the patient's age at the time of first exposure. Through the results, it was possible to show the direct impacts of chemotherapy on the odontogenesis process as well as factors such as the type of chemotherapy, the age of the individual at the time of first exposure and the dosage used. All of those should be taken into account when choosing a therapeutic protocol for an oncology patient. Besides, we observed the need for more studies in this area and that these should be standardized in order to allow an objective and direct analysis of comparable parameters, even when different approaches are used.

Male mate guarding in a socially monogamous mammal, the round-eared sengi: on costs and trade-offs

2009 ◽  
Vol 64 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Melanie Schubert ◽  
Carsten Schradin ◽  
Heiko G. Rödel ◽  
Neville Pillay ◽  
David O. Ribble
Keyword(s):  
Mate Guarding ◽  
Trade Offs ◽  
Socially Monogamous ◽  
Male Mate

Influence of food availability on mate-guarding behaviour of ladybirds

2018 ◽  
Vol 108 (6) ◽  
pp. 800-806
Author(s):  
D.D. Chaudhary ◽  
G. Mishra ◽  
Omkar
Keyword(s):  
Reproductive Output ◽  
Food Resource ◽  
Mate Guarding ◽  
The Other ◽  
Egg Viability ◽  
Influence Of Food ◽  
Food Conditions ◽  
Resource Conditions ◽  
Mating Conditions ◽  
Copulatory Behaviour

AbstractA recent study on ladybird,Menochilus sexmaculatus(Fabricius) demonstrates that males perform post-copulatory mate guarding in the form of prolonged mating durations. We investigated whether food resource fluctuation affects pre- and post-copulatory behaviour ofM. sexmaculatus. It has not been studied before in ladybirds. For this, adults were subjected to prey resource fluctuations sequentially at three levels: post-emergence (Poe; 10 days), pre-mating (Prm; 24 h) and post-mating (Pom; 5 days; only female). The food resource conditions at each level could be any one of scarce, optimal or abundant. Pre-copulatory and post-copulatory behaviour, and reproductive output were assessed. Post-emergence and pre-mating nutrient conditions significantly influenced the pre-copulatory behaviour. Males reared on scarce post-emergence conditions were found to require significantly higher number of mating attempts to establish mating unlike males in the other two food conditions. Under scarce post-emergence and pre-mating conditions, time to commencement of mating and latent period were high but opposite result was obtained for mate-guarding duration. Fecundity and per cent egg viability were more influenced by post-mating conditions, with scarce conditions stopping oviposition regardless of pre-mating and post-emergence conditions. Present results indicate that pre- and post-copulatory behaviour of ladybird is plastic in nature in response to food resource fluctuations.

scholarly journals Extrapair Fertilization in the Black-Browed Reed Warbler (Acrocephalus Bistrigiceps): Effects on Mating Status and Nesting Cycle of Cuckolded and Cuckolder Males

The Auk ◽  
2005 ◽  
Vol 122 (4) ◽  
pp. 1086-1096
Author(s):  
Shoji Hamao ◽  
Daichi S. Saito
Keyword(s):  
Incubation Period ◽  
Mate Guarding ◽  
Reed Warbler ◽  
Fertile Period ◽  
Mating Status ◽  
Trade Offs ◽  
Socially Monogamous ◽  
The Relationship ◽  
Extrapair Copulation

Abstract We studied the relationship between the occurrence of extrapair fertilizations (EPFs) and mating status and nesting cycle of mates, respectively, in a population of Black-browed Reed Warblers (Acrocephalus bistrigiceps). Overall, 6.4% (9 of 140) of the chicks were sired by extrapair males, and 13.5% (5 of 37) of the broods contained at least one extrapair chick. Socially polygynous males were cuckolded more frequently than socially monogamous males (40.0% and 3.7%, respectively). In three of four cases where cuckolded males were polygynous, the fertile periods of their mates overlapped. Except for two floating males that obtained EPFs, five out of seven cuckolder males were paired. Males succeeded in EPFs when the fertile period of the extrapair females largely overlapped the incubation period of their own mates. These findings are consistent with the hypothesis that there are trade-offs between extrapair copulation activity and both mate guarding and rearing of nestlings. Fertilisation Extraconjugale chez Acrocephalus bistrigiceps: Effets des Mâles Infidèles et Cocus sur le Statut de Couple et le Cycle de Nidification

Patterns of paediatric analgesic use in Africa: a systematic review

2012 ◽  
Vol 97 (12) ◽  
pp. 1086-1091 ◽  
Author(s):  
Parvaz Madadi ◽  
Ehijie F O Enato ◽  
Shir Fulga ◽  
Chinonye C Umeoduagu ◽  
Stuart M MacLeod ◽  
...  
Keyword(s):  
Observational Studies ◽  
African Country ◽  
Sickle Cell Anaemia ◽  
The Other ◽  
Essential Medicines ◽  
Drug Reactions ◽  
African Children ◽  
Who Standards ◽  
Analgesic Use ◽  
Suspected Adverse Drug Reactions

We conducted a systematic literature review with two objectives: (1) to assess reported patterns of analgesic use in African children and compare these observed patterns to the analgesics given in the WHO Essential Medicines List for Children (EMLc); and (2) to summarise outcomes related to effectiveness, adverse events, cost and accessibility of these analgesics. Eligible participants were children (≤12 years) living in any African country who received an analgesic administered with the intention of relieving pain in any setting. Thirty-four peer-reviewed, observational studies representing 7772 African children were accepted. Studies were conducted in 25 different regions of 12 countries. Pain was attributed to surgery, burns, sickle cell anaemia and conditions requiring palliation in 32% of children, and was unspecified in the other 68%. Of the three EMLc analgesics, paracetamol and ibuprofen were widely employed, constituting ∼60% of all analgesics, while morphine was used in 20 children (0.2%). There were 455 suspected adverse drug reactions which included 17 deaths. Analgesic use reported in African children appears to fall short of WHO standards.

Haul-out behaviour of two Ross seals off eastern Antarctica

2003 ◽  
Vol 15 (2) ◽  
pp. 257-258 ◽  
Author(s):  
COLIN SOUTHWELL
Keyword(s):  
Observational Data ◽  
Observational Studies ◽  
The Other ◽  
Accurate Assessment ◽  
Limited Information ◽  
Absolute Sense ◽  
Crabeater Seal ◽  
Abundance Estimates ◽  
Antarctic Seals ◽  
Using Data

Accurate assessment of the abundance of pinnipeds from visual surveys requires estimation of both the available (hauled-out) and unavailable (in-water) components of the population (Eberhardt et al. 1979). Continental estimates of the abundance of the four Antarctic seals are based on limited information on haul-out behaviour. In developing continental estimates, Erickson & Hanson (1990) corrected visual surveys of the hauled-out component of the species' populations using data from observational studies of haulout behaviour by Erickson et al. (1989). Erickson & Hanson (1990) point out that, because the observational studies did not account for an unknown fraction of seals that remained in the water during the peak haul-out period, their abundance estimates are minimum values. Further, Erickson & Hanson (1990) corrected the visual surveys for all four species using haul-out data for the crabeater seal only, as observational data for the other species were not available. This assumes that haul-out patterns are constant across species, which is largely untested. Consequently, there is potential for bias, in both a relative and absolute sense, in the estimated abundance of Antarctic seals.

scholarly journals Binary contrasts for unordered polytomous regressors

2020 ◽  
Author(s):  
Jeremy Freese ◽  
Sasha Johfre
Keyword(s):  
Observational Studies ◽  
The Other ◽  
Regression Coefficients ◽  
Reference Category

In observational studies, regression coefficients for categorical regressors are overwhelmingly presented in terms of contrasts with a reference category. For unordered regressors with many categories, however, this approach often focuses on contrasting different pairs of categories with one another with little substantive rationale for foregrounding those comparisons. Mean contrasts, which compare categories to the overall mean, provide an alternative to the reference category, but the magnitude of mean contrasts is conflated with the relative sizes of the categories. Instead, binary contrasts compare a category to all the other categories, allowing the familiar interpretation for dichotomous regressors. We provide a Stata package that computes binary contrasts.

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