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A molecular phylogeny of the genus Psittacula sensu lato (Aves: Psittaciformes: Psittacidae: Psittacula, Psittinus, Tanygnathus, † Mascarinus) with taxonomic implications
No full textBraun, Michael P., Datzmann, Thomas, Arndt, Thomas, Reinschmidt, Matthias, Schnitker, Heinz, Bahr, Norbert, Sauer-Gürth, Hedwig, Wink, Michael (2019): A molecular phylogeny of the genus Psittacula sensu lato (Aves: Psittaciformes: Psittacidae: Psittacula, Psittinus, Tanygnathus, † Mascarinus) with taxonomic implications. Zootaxa 4563 (3): 547-562, DOI: 10.11646/zootaxa.4563.3.
Belocercus S. Muller 1847
No full textBelocercus S. Müller Type species: Psittacus barbatulatus Bechstein = Psittacus longicauda Boddaert Morphology/distribution: no red shoulder patch; medium size, very long tail; male with black lores, horizontal black beard stripe, green crown and rose-coloured cheeks, not encircling hindneck; upper mandible red, lower mandible brown; females duller with completely dark-brown bill and shorter tail. Distribution: Malay Peninsula to Borneo and Sumatra. Several subspecies exist within the B. longicauda complex, and further investigation is required to resolve the evolutionary history and taxonomy of Belocercus, which shares a common ancestor with Psittacula s.s. Based on its unclear phylogenetic position, with low support values, and morphological differences from this clade, however, we regard it as a separate genus.Published as part of Braun, Michael P., Datzmann, Thomas, Arndt, Thomas, Reinschmidt, Matthias, Schnitker, Heinz, Bahr, Norbert, Sauer-Gürth, Hedwig & Wink, Michael, 2019, A molecular phylogeny of the genus Psittacula sensu lato (Aves: Psittaciformes: Psittacidae: Psittacula, Psittinus, Tanygnathus, † Mascarinus) with taxonomic implications, pp. 547-562 in Zootaxa 4563 (3) on page 558, DOI: 10.11646/zootaxa.4563.3.8, http://zenodo.org/record/260147
Psittinus Blyth 1842
No full text<i>Psittinus</i> Blyth <p> Type species: <i>Psittacus malaccensis</i> Latham = <i>Psittacus cyanurus</i> J. R. Forster</p> <p> <b>Morphology/distribution:</b> red bend of wing and red underwing coverts; small size, very short tail; sexually dichromatic; yellow edging on wing coverts; males with bluish head, otherwise predominantly green head; red upper mandible, females with brown head and bill. Distribution: Malay Peninsula to Borneo and Sumatra.</p> <p> <i>Psittinus,</i> which is represented by nominate <i>cyanurus</i> in our dataset, is sister to a clade formed by <i>Tanygnathus, Belocercus</i> and <i>Psittacula s.s.</i> It represents a long branch within the <i>Psittacula s.l.</i> group, which together with its distinct morphological traits supports its status as a separate genus.</p>Published as part of <i>Braun, Michael P., Datzmann, Thomas, Arndt, Thomas, Reinschmidt, Matthias, Schnitker, Heinz, Bahr, Norbert, Sauer-Gürth, Hedwig & Wink, Michael, 2019, A molecular phylogeny of the genus Psittacula sensu lato (Aves: Psittaciformes: Psittacidae: Psittacula, Psittinus, Tanygnathus, † Mascarinus) with taxonomic implications, pp. 547-562 in Zootaxa 4563 (3)</i> on pages 557-558, DOI: 10.11646/zootaxa.4563.3.8, <a href="http://zenodo.org/record/2601472">http://zenodo.org/record/2601472</a>
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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
Tanygnathus Wagler 1832
No full text<i>Tanygnathus</i> Wagler <p> Type species: <i>Tanygnathus macrorhynchus</i> Wagler = <i>Psittacus megalorynchos</i> Boddaert</p> <p> <b>Morphology/distribution:</b> no red shoulder patch; medium to large size; very large bills; medium sized, rounded tails; sexual dimorphism weak or absent; yellow edging on wing coverts; black lore and blue crown only in <i>T. gramineus</i>, otherwise predominantly green head, red upper and lower mandible, juveniles duller. Distribution only on islands of the Philippines and Wallacea.</p> <p> The genus <i>Tanygnathus</i> clusters within the former genus <i>Psittacula</i> with high support values. <i>Tanygnathus</i> forms a clade with <i>Psittacula s.s.</i> and <i>Belocercus.</i> Its morphological characters (bill size, tail length and shape, no sexual dimorphism in two of the four species) apparently evolved quite quickly away from the general pattern in <i>Psittacula</i>. The monophyletic clade of <i>T. megalorynchos</i> and <i>T. sumatranus</i> clusters together with <i>Psittinus</i>, <i>Belocercus longicauda</i>, and the <i>Psittacula s.s.</i> clade in our dataset..</p>Published as part of <i>Braun, Michael P., Datzmann, Thomas, Arndt, Thomas, Reinschmidt, Matthias, Schnitker, Heinz, Bahr, Norbert, Sauer-Gürth, Hedwig & Wink, Michael, 2019, A molecular phylogeny of the genus Psittacula sensu lato (Aves: Psittaciformes: Psittacidae: Psittacula, Psittinus, Tanygnathus, † Mascarinus) with taxonomic implications, pp. 547-562 in Zootaxa 4563 (3)</i> on page 558, DOI: 10.11646/zootaxa.4563.3.8, <a href="http://zenodo.org/record/2601472">http://zenodo.org/record/2601472</a>
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