1,721,072 research outputs found

    Heinrich Uzel, the father of Thysanoptera studies

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    Fedor, Peter J., Doričová, Martina, Prokop, Pavol, Mound, Laurence A. (2010): Heinrich Uzel, the father of Thysanoptera studies. Zootaxa 2645 (1): 55-63, DOI: 10.11646/zootaxa.2645.1.3, URL: https://biotaxa.org/Zootaxa/article/view/zootaxa.2645.1.

    Infanticide or interference : Does the great reed warbler selectively destroy eggs?

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    Infanticide, the killing of offspring by adult conspecifics, has been demonstrated in many insect, mammal and bird species. In contrast to selective pressures influencing infanticide in other species, egg destruction in birds is thought to primarily represent interference competition for food, nest sites or predator-free nesting space. In the case of the great reed warbler, two opposing hypotheses exist for the explanation of its egg destruction behaviour. Our study tested these hypotheses separately by manipulating the presence of real conspecific, familiar and unfamiliar eggs and nests inside polygynous and monogamous great reed warbler territories. Out of 147 experimental nests placed in the vicinity of 49 active great reed warbler nests, only conspecific eggs were preyed upon by great reed warblers. Furthermore, significantly more great reed warbler nests were destroyed in polygynous than monogamous territories. These results support the hypothesis that egg destruction behaviour in this species is motivated intraspecifically and most probably intrasexually

    Infanticide or interference : Does the great reed warbler selectively destroy eggs?

    No full text
    Infanticide, the killing of offspring by adult conspecifics, has been demonstrated in many insect, mammal and bird species. In contrast to selective pressures influencing infanticide in other species, egg destruction in birds is thought to primarily represent interference competition for food, nest sites or predator-free nesting space. In the case of the great reed warbler, two opposing hypotheses exist for the explanation of its egg destruction behaviour. Our study tested these hypotheses separately by manipulating the presence of real conspecific, familiar and unfamiliar eggs and nests inside polygynous and monogamous great reed warbler territories. Out of 147 experimental nests placed in the vicinity of 49 active great reed warbler nests, only conspecific eggs were preyed upon by great reed warblers. Furthermore, significantly more great reed warbler nests were destroyed in polygynous than monogamous territories. These results support the hypothesis that egg destruction behaviour in this species is motivated intraspecifically and most probably intrasexually

    Dummy birds in artificial nest studies: an experiment with Red-backed Shrike Lanius collurio

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    Capsule Dummy birds placed on artificial nests increase nest survival, and their use should be considered in future studies of nest predation.Scientific Grant Agency VEGA [1/3257/06

    Management of reedbeds: mosaic reed cutting does not affect prey abundance and nest predation rate of reed passerine birds

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    Reed passerine birds are strict habitat specialists inhabiting reedbed habitats. In Europe, many of these species are threatened due to loss and degradation of natural reedbeds. Another important factor that can negatively affect the abundance of reed passerines is commercial reed harvesting. Previous studies have shown negative impacts of large-scale winter reed cutting on passerine breeding assemblages and arthropod communities. The effect of reed cutting on a small scale, however, has not been studied experimentally to date. The aim of this study was to investigate whether and how small-scale, mosaic reed cutting influences prey abundance and nest predation rate of reed passerines. In June, after the reed had reached maturity, we conducted nest predation experiments with artificial nests and arthropod sampling using pan traps in cut reed patches, adjacent uncut reed patches and unmanaged reedbed. We found no differences in the risk of egg predation between three types of reedbeds. In contrast, the abundance of arthropods in cut and adjacent uncut reed patches was significantly higher than that in unmanaged reedbed. We assume this was caused by habitat heterogeneity, small size of cut patches and their rapid recolonization by arthropods from adjacent uncut patches. Our results suggest that in contrast to large-scale reed cutting, small-scale, mosaic reed cutting has no negative effect on nest survival and food abundance of reed passerine birds. However, given that we performed all experiments in June, i.e., when the reed was mature, our findings cannot be generalized to whole breeding period of all reed passerine birds. Therefore, temporal variation in nest predation rate and arthropod abundance in managed and unmanaged reedbeds during the entire breeding season should be examined in future studies

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Preservice teachers’ memories of their secondary science education experiences

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    Understanding preservice teachers’ memories of their education may aid towards articulating high-impact teaching practices. This study describes 246 preservice teachers’ perceptions of their secondary science education experiences through a questionnaire and 28-item survey. ANOVA was statistically significant about participants’ memories of science with 15 of the 28 survey items. Descriptive statistics through SPSS further showed that a teacher’s enthusiastic nature (87%) and positive attitude towards science (87%) were regarded as highly memorable. In addition, explaining abstract concepts well (79%), and guiding the students’ conceptual development with practical science activities (73%) may be considered as memorable secondary science teaching strategies. Implementing science lessons with one or more of these memorable science teaching practices may “make a difference” towards influencing high school students’ positive long-term memories about science and their science education. Further research in other key learning areas may provide a clearer picture of high-impact teaching and a way to enhance pedagogical practices
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