1,720,959 research outputs found
Temporally consistent species differences in parasite infection but no evidence for rapid parasite-mediated speciation in Lake Victoria cichlid fish
No full textParasites may have strong eco-evolutionary interactions with their hosts. Consequently, they may contribute to host diversification. The radiation of cichlid fish in Lake Victoria provides a good model to study the role of parasites in the early stages of speciation. We investigated patterns of macroparasite infection in a community of 17 sympatric cichlids from a recent radiation and 2 older species from 2 non-radiating lineages, to explore the opportunity for parasite-mediated speciation. Host species had different parasite infection profiles, which were only partially explained by ecological factors (diet, water depth). This may indicate that differences in infection are not simply the result of differences in exposure, but that hosts evolved species-specific resistance, consistent with parasite-mediated divergent selection. Infection was similar between sampling years, indicating that the direction of parasite-mediated selection is stable through time. We morphologically identified 6 Cichlidogyrus species, a gill parasite that is considered a good candidate for driving parasite-mediated speciation, because it is host species-specific and has radiated elsewhere in Africa. Species composition of Cichlidogyrus infection was similar among the most closely related host species (members of the Lake Victoria radiation), but two more distantly related species (belonging to non-radiating sister lineages) showed distinct infection profiles. This is inconsistent with a role for Cichlidogyrus in the early stages of divergence. To conclude, we find significant interspecific variation in parasite infection profiles, which is temporally consistent. We found no evidence that Cichlidogyrus-mediated selection contributes to the early stages of speciation. Instead, our findings indicate that species differences in infection accumulate after speciation.Rijksuniversiteit GroningenUniversität BernParasite data:
Parasite taxa (not considering the diversity of Cichlidogyrus) infecting cichlid species (belonging to the radiation lineage and to the older Astatoreochromis alluaudi lineage that did not speciate) at Makobe Island in southern Lake Victoria.
For temporal consistency analysis, we also used ectoparasite data from Karvonen et al. 2018 (https://doi.org/10.5061/dryad.93n2t24).
Cichlidogyrus data:
Morphospecies of Cichlidogyrus infecting cichlid species (form three lineages) at three locations in southern Lake Victoria. Since species of Cichlidogyrus were new to science at the moment of publication, they were provisionally named with roman numbers. Missing values: monogenean specimens impossible to identify with certitude
Temporally consistent species differences in parasite infection but no evidence for rapid parasite-mediated speciation in Lake Victoria cichlid fish
No full textParasites may have strong eco-evolutionary interactions with their hosts. Consequently, they may contribute to host diversification. The radiation of cichlid fish in Lake Victoria provides a good model to study the role of parasites in the early stages of speciation. We investigated patterns of macroparasite infection in a community of 17 sympatric cichlids from a recent radiation and 2 older species from 2 non-radiating lineages, to explore the opportunity for parasite-mediated speciation. Host species had different parasite infection profiles, which were only partially explained by ecological factors (diet, water depth). This may indicate that differences in infection are not simply the result of differences in exposure, but that hosts evolved species-specific resistance, consistent with parasite-mediated divergent selection. Infection was similar between sampling years, indicating that the direction of parasite-mediated selection is stable through time. We morphologically identified 6 Cichlidogyrus species, a gill parasite that is considered a good candidate for driving parasite-mediated speciation, because it is host species-specific and has radiated elsewhere in Africa. Species composition of Cichlidogyrus infection was similar among the most closely related host species (members of the Lake Victoria radiation), but two more distantly related species (belonging to non-radiating sister lineages) showed distinct infection profiles. This is inconsistent with a role for Cichlidogyrus in the early stages of divergence. To conclude, we find significant interspecific variation in parasite infection profiles, which is temporally consistent. We found no evidence that Cichlidogyrus-mediated selection contributes to the early stages of speciation. Instead, our findings indicate that species differences in infection accumulate after speciation.Rijksuniversiteit GroningenUniversität BernParasite data:
Parasite taxa (not considering the diversity of Cichlidogyrus) infecting cichlid species (belonging to the radiation lineage and to the older Astatoreochromis alluaudi lineage that did not speciate) at Makobe Island in southern Lake Victoria.
For temporal consistency analysis, we also used ectoparasite data from Karvonen et al. 2018 (https://doi.org/10.5061/dryad.93n2t24).
Cichlidogyrus data:
Morphospecies of Cichlidogyrus infecting cichlid species (form three lineages) at three locations in southern Lake Victoria. Since species of Cichlidogyrus were new to science at the moment of publication, they were provisionally named with roman numbers. Missing values: monogenean specimens impossible to identify with certitude
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
When slow explorers are fast: personality-related differences in timing of migration in red knots Calidris canutus
No full text<p>Title: "<strong><span>When slow explorers are fast: personality-related differences in timing of migration in red knots <em>Calidris canutus</em></span></strong>"<br>Authors: Selin Ersoy; Ton G. G. Groothuis; Theunis Piersma & Allert Bijleveld</p>
<p>GENERAL INFORMATION</p>
<p>Date of the data collection: Catching between 14 August 2018 - 5 August 2019<br>Geographic location of data collection: Western Dutch Wadden Sea (53°15'N, 5°15'E) <br>Corresponding author information: Selin Ersoy, NIOZ Royal Netherlands Institute for Sea Research, Department of Coastal Systems, PO Box 59, 1790 AB Den Burg, Texel, The Netherlands, [email protected] </p>
<p>METHODS<br>Isotope data: Red blood cell and plasma d13C and d15N isotopes collected from the blood samples of red knots.<br>Exploration speed: Movement tracjectories were collected from the recordings of the top camera during experiments in the mobile arena. We used the distance between estimated positions to calculate speed. Errors in the positioning algorithm were filtered by excluding speeds higher than 200 cm/s. An individual’s exploration speed was calculated as the average speed during each 20 min trial.</p>
<p>DATA & FILE OVERVIEW</p>
<p>All_Isotope_RedKnot.csv : Red blood cell and plasma d13C and d15N isotopes collected from the blood samples of juvenile and adult red knots<br> Column 1: RingNr: Unique metal ring number of red knots. Ring were put on the legs<br> Column 2: Type: Blood type plasma or red blood cell<br> Column 3: Repeat: If there is a repeated samples of an individual<br> Column 4: d15N: Nitrogen 15 Isotope value <br> Column 5: d13C: Carbon 13 Isotope value<br> Column 6: Comments: important commments about samples</p>
<p>KnotData.csv : Primaries and Exploration speed repeated measures from Juvenile and Adult red knots<br> Column 1: RingNr: Unique metal ring number of red knots. Ring were put on the legs<br> Column 2: Catch months<br> Column 3: Catch day<br> Column 4: Catch year<br> Column 5: Sex (m for male, f for female)<br> Column 6: P1: first primary score <br> Column 7: P2: second primary score <br> Column 8: P3: third primary score <br> Column 9: P4: forth primary score <br> Column 10: P5: fifth primary score <br> Column 11: P6: sixth primary score <br> Column 12: P7: seventh primary score <br> Column 13: P8: eight primary score <br> Column 14: P9: nineth primary score <br> Column 15: P10: tenth primary score <br> Column 16: Active moult (yes-no)<br> Column 17: Total primary score<br> Column 18: LogMeanF01: Exploratory score of individual measured in mobile arena (mean speed cm/sec) measured through automated tracking </p>
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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