scholarly journals The cheek plumage patch is an amplifier of dominance in great tits

2007 ◽  
Vol 4 (1) ◽  
pp. 12-15 ◽  
Author(s):  
Ismael Galván ◽  
Juan José Sanz

Amplifiers are signals that enhance the perception of other signals or cues, but no studies to date provide empirical evidence for the role of these signals in a reproductive context. Here we use the white cheek patch of great tits as a model for studying this issue. Aggressive interactions decrease patch immaculateness, so patch size may be an amplifier of dominance, that is, more clearly reveal status. If so, in high-quality individuals patch size should correlate positively with reproductive success (here estimated by laying date, assuming that the earlier the better), whereas low-quality individuals with a large patch should only more clearly reveal their low quality and thus suffer low reproductive success, which is exactly the pattern found in males. In contrast, the cheek patch does not seem to function as an amplifier in female great tits.

2015 ◽  
Vol 2 (11) ◽  
pp. 150282 ◽  
Author(s):  
Tamal Roy ◽  
Anuradha Bhat

Winner–loser relations among group-living individuals are often measured by the levels of aggressive interactions between them. These interactions are typically driven by competition for resources such as food and mates. It has been observed in recent studies on zebrafish that dominant males generally have higher total reproductive success than their less aggressive subordinate counterparts. This study aimed to test whether males who monopolized a food resource (winners) also displayed higher levels of aggression than the males who were unsuccessful (losers). Further, the study also tested whether the same ‘winner’ males were also able to monopolize interactions with females during courtship. The results from these experiments showed that while males monopolizing food resources (winners) demonstrated higher levels of agonistic interactions than the losers, the average number of courtship interactions initiated by either of the males (i.e. winners/losers) with a female was not significantly different. A significant relationship was obtained between the number of aggressive interactions and feeding latencies of males in the context of food monopolization. This indicated that there could be a linkage between boldness defined by feeding latency in a novel environment and agonistic responses. The probable role of nature of resources, resource availability and distribution in determining the outcomes of dyadic contests is discussed.


PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e2802 ◽  
Author(s):  
Raquel Vasconcelos ◽  
Sara Rocha ◽  
Xavier Santos

BackgroundThe extent of social behaviour among reptiles is underappreciated. Two types of aggregations are recognized in lizards: ecological and social, i.e., related to the attraction to a site or to animals of the same species, respectively. As most lizards are territorial, aggregations increase the probability of aggressive interactions among individuals, a density-dependent behaviour.MethodsAfter some spurious observations of aggregation behaviour in the endemic Cabo Verde nocturnal geckoTarentola substituta,we conducted a field-based study in order to thoroughly characterize it. We sampled 48 transects and 40 10 × 10 m quadrats on São Vicente Island to describe the incidence, size and composition of aggregations and to study the effect of gecko and refuge density, plus refuge quality, on refuge sharing. We hypothesize that when density of animals and scarcity of high-quality refuges is higher, lizards have increased probability of aggregating. We also predict a consistent pattern of size and composition of groups (male–female pairs, only one adult male per group) throughout the year if there is a selected behaviour to avoid agonistic interactions, and low thermal advantage to aggregating individuals.ResultsWe present one of the first evidences of aggregation for Phyllodactylidae geckos. We found thatT. substitutaforms aggregations around 30–40% of the time, and that refuges are almost always shared by a female-male pair, sometimes with a juvenile, probably a mechanism to avoid aggressive interactions. We also observed that refuge sharing is dependent on refuge quality, as medium–large (thermally more stable and positively selected) rocks are shared much more frequently than small ones, but independent of adult sizes. Refuge sharing is also directly related to the density of geckos and inversely related to the density of high-quality refuges. We found no relation between body temperatures of geckos and refuge sharing when controlling the effect of rock/air temperature, suggesting that huddling does not improve thermoregulation.DiscussionOur results suggest that in this harsh environment (rocks reach 46 °C) aggregation incidence is mainly driven by an ecological factor (scarcity of high-quality refuges) and its intersexual composition by social factors (avoidance of agonistic interactions by males, and possible increased reproductive success of the pair). This study sheds some light on the little explored gecko aggregation behaviour and other studies should follow.


2019 ◽  
Vol 10 (11) ◽  
pp. 1057-1064
Author(s):  
Katsuhiko Hirasawa ◽  

Staff members at a movie company Daiei, known for presumably the world’s best film technology, continued to produce movies for several months even after the company went bankrupt. It was because they desired to make outstanding films. A director can create a high-quality film by combining the skills and ideas of such staff. Akira Kurosawa named the group that could produce excellent works the “Community of Talents”. By using research on a community as a clue, this paper aims to highlight how the “Community of Talents” is organized. First I point out that a “Community of Talents” is formulated primarily by the labor of the staff based on Kumazawa’s “Community on the Shop Floor”. The paper subsequently refers to research by Heinrich Nicklish, a representative researcher on the study of community in Germany, in an attempt to verify that the community is a group of people established on functions. Lastly, the paper explores Guido Fisher’s research to reveal the role of democratic leadership centered on the director who transforms the objectified staff in the organization into an independently-minded presence and help them prove their abilities. The paper continues to emphasize the significance of leadership in the formation of the “Community of Talents”.


2017 ◽  
Vol 1 (2) ◽  
pp. 152-170
Author(s):  
Ahmad Ubaidillah

Throughout my experience in tracking down and reading books on faith-based economics, in this case Islam, there are no books that specifically list the title of "Islamic economics". If there is, it is only initiated or introduced. Most books coming down to us still use the titles starting with the word, for example, system, concept, principle, or the doctrine of Islamic economics. Why do the authors of the book Islamic economics seem not dared to give his book title with label "science"? I presume that Islamic economics has not been considered as a science. In building a science, methodology is required. Islamic Economics also requires a well-established methodology to build the foundation of science. The study answers questions; how is methodology which is offered by Muhammad Akram Khan to build Islamic economics. The method used in this research is the study of literature with qualitative approach.The result of study concludes that Khan offers methodology of Islamic economics, if summarized, written as follows: First, Islamic economics uses a framework derived from the texts of divinity (revelation). Second, Islamic economics uses the inductive method, which gives witness to the truth or falsity assumptions and predictions about the two criteria of rationality and empirical evidence. Third, Islamic economy is built on ethical values ​​such as justice, virtue, moderation, sacrifice, caring for others, in the analysis, as behavioral parameters. Fourth, Islamic economics is a normative discipline. Islamic Economics investigates ways and means to change the existing economy with Islamic economy. Fifth, Islamic economics ask different questions with conventional economics. Its attention is on welfare (falah) human and creating social and institutional conditions that maximize falah in society. Clearly, Islamic economics strongly supports research programs that help maximize falah. Furthermore, Khan elaborates several issues related to the methodology that often appears in the forum of Islamic economists. There are some problems that Khan proposes, they are the interaction with modern economics, the role of revelation, assuming ideal Islamic society, and the general theory of Islamic economics.


2017 ◽  
Vol 93 (4) ◽  
pp. 177-202 ◽  
Author(s):  
Emily E. Griffith

ABSTRACT Auditors are more likely to identify misstatements in complex estimates if they recognize problematic patterns among an estimate's underlying assumptions. Rich problem representations aid pattern recognition, but auditors likely have difficulty developing them given auditors' limited domain-specific expertise in this area. In two experiments, I predict and find that a relational cue in a specialist's work highlighting aggressive assumptions improves auditors' problem representations and subsequent judgments about estimates. However, this improvement only occurs when a situational factor (e.g., risk) increases auditors' epistemic motivation to incorporate the cue into their problem representations. These results suggest that auditors do not always respond to cues in specialists' work. More generally, this study highlights the role of situational factors in increasing auditors' epistemic motivation to develop rich problem representations, which contribute to high-quality audit judgments in this and other domains where pattern recognition is important.


Agronomy ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 377
Author(s):  
Katrin Kuhlmann ◽  
Bhramar Dey

Seed rules and regulations determine who can produce and sell seeds, which varieties will be available in the market, the quality of seed for sale, and where seed can be bought and sold. The legal and regulatory environment for seed impacts all stakeholders, including those in the informal sector, through shaping who can participate in the market and the quality and diversity of seed available. This paper addresses a gap in the current literature regarding the role of law and regulation in linking the informal and formal seed sectors and creating more inclusive and better governed seed systems. Drawing upon insights from the literature, global case studies, key expert consultations, and a methodology on the design and implementation of law and regulation, we present a framework that evaluates how regulatory flexibility can be built into seed systems to address farmers’ needs and engage stakeholders of all sizes. Our study focuses on two key dimensions: extending market frontiers and liberalizing seed quality control mechanisms. We find that flexible regulatory approaches and practices play a central role in building bridges between formal and informal seed systems, guaranteeing quality seed in the market, and encouraging market entry for high-quality traditional and farmer-preferred varieties.


2021 ◽  
Vol 2 ◽  
pp. 263348952199419
Author(s):  
Cara C Lewis ◽  
Kayne Mettert ◽  
Aaron R Lyon

Background: Despite their inclusion in Rogers’ seminal diffusion of innovations theory, few implementation studies empirically evaluate the role of intervention characteristics. Now, with growing evidence on the role of adaptation in implementation, high-quality measures of characteristics such as adaptability, trialability, and complexity are needed. Only two systematic reviews of implementation measures captured those related to the intervention or innovation and their assessment of psychometric properties was limited. This manuscript reports on the results of eight systematic reviews of measures of intervention characteristics with nuanced data regarding a broad range of psychometric properties. Methods: The systematic review proceeded in three phases. Phase I, data collection, involved search string generation, title and abstract screening, full text review, construct assignment, and citation searches. Phase II, data extraction, involved coding psychometric information. Phase III, data analysis, involved two trained specialists independently rating each measure using PAPERS (Psychometric And Pragmatic Evidence Rating Scales). Results: Searches identified 16 measures or scales: zero for intervention source, one for evidence strength and quality, nine for relative advantage, five for adaptability, six for trialability, nine for complexity, and two for design quality and packaging. Information about internal consistency and norms was available for most measures, whereas information about other psychometric properties was most often not available. Ratings for psychometric properties fell in the range of “poor” to “good.” Conclusion: The results of this review confirm that few implementation scholars are examining the role of intervention characteristics in behavioral health studies. Significant work is needed to both develop new measures (e.g., for intervention source) and build psychometric evidence for existing measures in this forgotten domain. Plain Language Summary Intervention characteristics have long been perceived as critical factors that directly influence the rate of adopting an innovation. It remains unclear the extent to which intervention characteristics including relative advantage, complexity, trialability, intervention source, design quality and packaging, evidence strength and quality, adaptability, and cost impact implementation of evidence-based practices in behavioral health settings. To unpack the differential influence of these factors, high quality measures are needed. Systematic reviews can identify measures and synthesize the data regarding their quality to identify gaps in the field and inform measure development and testing efforts. Two previous reviews identified measures of intervention characteristics, but they did not provide information about the extent of the existing evidence nor did they evaluate the host of evidence available for identified measures. This manuscript summarizes the results of nine systematic reviews (i.e., one for each of the factors listed above) for which 16 unique measures or scales were identified. The nuanced findings will help direct measure development work in this forgotten domain.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Cynthia Reséndiz-Infante ◽  
Gilles Gauthier

AbstractMany avian migrants have not adjusted breeding phenology to climate warming resulting in negative consequences for their offspring. We studied seasonal changes in reproductive success of the greater snow goose (Anser caerulescens atlantica), a long-distance migrant. As the climate warms and plant phenology advances, the mismatch between the timing of gosling hatch and peak nutritive quality of plants will increase. We predicted that optimal laying date yielding highest reproductive success occurred earlier over time and that the seasonal decline in reproductive success increased. Over 25 years, reproductive success of early breeders increased by 42%, producing a steeper seasonal decline in reproductive success. The difference between the laying date producing highest reproductive success and the median laying date of the population increased, which suggests an increase in the selection pressure for that trait. Observed clutch size was lower than clutch size yielding the highest reproductive success for most laying dates. However, at the individual level, clutch size could still be optimal if the additional time required to acquire nutrients to lay extra eggs is compensated by a reduction in reproductive success due to a delayed laying date. Nonetheless, breeding phenology may not respond sufficiently to meet future environmental changes induced by warming temperatures.


Author(s):  
James ROSE

ABSTRACT Within the context of the work and achievements of James Croll, this paper reviews the records of direct observations of glacial landforms and sediments made by Charles Lyell, Archibald and James Geikie and James Croll himself, in order to evaluate their contributions to the sciences of glacial geology and Quaternary environmental change. The paper outlines the social and physical environment of Croll's youth and contrasts this with the status and experiences of Lyell and the Geikies. It also outlines the character and role of the ‘Glasgow School’ of geologists, who stimulated Croll's interest into the causes of climate change and directed his focus to the glacial and ‘interglacial’ deposits of central Scotland. Contributions are outlined in chronological order, drawing attention to: (i) Lyell's high-quality observations and interpretations of glacial features in Glen Clova and Strathmore and his subsequent rejection of the glacial theory in favour of processes attributed to floating icebergs; (ii) the significant impact of Archibald Geikie's 1863 paper on the ‘glacial drift of Scotland’, which firmly established the land-ice theory; (iii) the fact that, despite James Croll's inherent dislike of geology and fieldwork, he provided high-quality descriptions and interpretations of the landforms and sediments of central Scotland in order to test his theory of climate change; and (iv) the great communication skills of James Geikie, enhanced by contacts and evidence from around the world. It is concluded that whilst direct observations of glacial landforms and sediments were critical to the long-term development of the study of glaciation, the acceptance of this theory was dependent also upon the skills, personality and status of the Geikies and Croll, who developed and promoted the concepts. Sadly, the subsequent rejection of the land-ice concept by Lyell resulted in the same factors challenging the acceptance of the glacial theory.


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