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“Likkle but Tallawah: Evolution and Phylogeography of a Caribbean Adaptive Radiation, the Anoline Lizards of Jamaica”
No full textUnderstanding diversification is a major goal of evolutionary biology, and the study of adaptive radiations has been a key part of this pursuit – especially replicate adaptive radiations, the natural experiments that help us illuminate the course of evolution. The four replicate radiations of Greater Antillean Anolis lizards have become a classic example of the power of such natural experiments. Yet, despite all we know about these four faunas, much remains unknown about the series of events that gave rise to each of these assemblages.
In Chapter 1, I inferred brand new nuclear and mitochondrial phylogenies for the Jamaican Anolis to investigate the relationships among species and to test previously-proposed hypotheses sug-gesting differences between the two phylogenies. Even though both tree topologies received strong support by traditional metrics, I found discordance between the nuclear and mitochondrial phylogenies at almost every major node, along with low concordance between the underlying data and the consensus topologies, suggesting that the evolutionary history of the Jamaican anoles proceeded in a not-strictly-treelike fashion. These findings also hold implications for processes operating early in the history of the Jamaican adaptative radiation, including putative mitochondrial capture. Moreover, with higher sample sizes and more widespread geographic sampling relative to previous studies, I discovered new relationships in both trees. I closed this species-level analysis by describing broad scale patterns of genetic variation across the clade, revealing that some species harbor much higher diversity than others, including geographically-structured variation.
In Chapter 2, I studied patterns of intraspecific diversity suggested by the results of the first chapter, and searched for evidence of independently-evolving lineages within each of Jamaica’s five widespread anole species. Here, I uncovered evidence for deep, spatially-circumscribed structuring of genetic variation in two species, diffuse clustering in a third, and shallow variation in the last two. After characterizing intraspecific genetic clusters across the landscape, I examined patterns of genetic exchange between clusters to test whether intraspecific variation follows an isolation-by-distance (IBD) pattern, where major barriers to dispersal occur, and which processes underlie shared variation among lineages. Results of these analyses showed that species vary in their fit to an IBD model, and the two species with deep structuring also exhibited clear evidence of barriers to dispersal along the edges of intraspecific lineage ranges. In the three species with evident clustering, I found evidence for non-ILS processes which pointed to major areas of elevated genetic exchange between lineages – and to areas where such exchange was depressed. I used the patterns discovered in the above analyses to compare the spatial distribution of lineages between co-distributed species, and to test whether mor-phological variation differs along the same lines as genetic variation. Taken together, these results also made it possible to test subspecies classifications in two of Jamaica’s anole species, proposed over half a century ago. My findings indicated strong evidence for subspecies hypothesis in one species, and mixed evidence for those of the second.
In Chapter 3, I used phylogenetic network inference to test the hypothesis of reticulate evolution suggested by the results in Chapter 1. Complementing the finding of high discordance in the bifurcating tree (Chapter 1), I uncovered evidence in the nuclear dataset consistent with ancient hybridization: the first between the two lineages involved in putative mitochondrial capture, the second in the history of the radiation’s only remote species. To put these events in context, and to better understand the past processes leading to presently-observed patterns, I assembled a new geological timeline of Jamaica, inferred a time-calibrated tree, and performed model-based biogeographic history estimation. The above-water geology of Jamaica over the past ~20 million years involves the piecemeal assembly of the island from three major blocks. Across this shifting landscape, I inferred a mid-Miocene origin for the Jamaican anole clade in the most topographically-complex block of the three, which also emerged from the Caribbean Sea earliest: the Blue Mountain Block in the east. Biogeographic history estimation supported this finding and revealed two pulses of concurrent diversification in three species groups: first, late Miocene splits between lineages along the Blue Mountains’ growing elevational gradient, and second, Pliocene divergences between lowland lineages on either side of the mountains.
Taken together, these results shed light on the potential processes underlying the diversification of a classic Caribbean adaptive radiation and illuminate the patterns we see in the present day
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
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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