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Figure 1 in Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes
No full textFigure 1. Distribution of species of the speckled rattlesnake (Crotalus mitchellii) species complex in western North America. Symbols represent sampling locations and indicate species and populations recognised in this publication.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13-16) on page 990, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
Figure 2 in Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes
No full textFigure 2. Maximum likelihood phylogram constructed from three concatenated mitochondrial gene fragments (ATP, cyt-b and 16S). Nodal support values are posterior probabilities from a partitioned Bayesian analysis. Populations or species discussed in the text are indicated with vertical bars.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13-16) on page 998, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
Figure 4 in Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes
No full textFigure 4. Scatterplots of first three axes from linear discriminant analyses of phenotypic data (a), principal component axes of microsatellite alleles (b), principal component axes of concatenated mitochondrial sequences (c), and principal component axes of concatenated nSNP data (d). Colour scheme: Crotalus angelensis = pink, C. mitchellii = red, C. polisi = gold, C. pyrrhus mainland = blue, C. pyrrhus El Muerto Island = black, C. pyrrhus Smith Island = brown, C. thalassoporus = purple.Published as part of Meik, Jesse M., Schaack, Sarah, Flores-Villela, Oscar & Streicher, Jeffrey W., 2018, Integrative taxonomy at the nexus of population divergence and speciation in insular speckled rattlesnakes, pp. 989-1016 in Journal of Natural History 52 (13-16) on page 1000, DOI: 10.1080/00222933.2018.1429689, http://zenodo.org/record/517455
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
It's Not Just The Straws: Investigating the Biology and Genetics of Sea Turtles and the Implications of Climate Change
No full texthttps://rdc.reed.edu/v1/resources/17510c11-1b11-47c8-ab86-9df7072d6c2b/thumb/128.jpgThis undergraduate thesis delves into the evolutionary genetics of green sea turtles, aiming to uncover insights into their population dynamics, implications for conservation efforts; and newer perspectives on the consequences of extinction. Through a combination of literature review, bioinformatics analysis, and integration of historical and environmental data, this thesis addresses critical questions of green sea turtle populations within an evolutionary genetics framework. By examining patterns of genetic diversity and population structure, I intend to shed light on the adaptive potential of green sea turtles and their capacity to cope with environmental challenges, especially in our current climate crisis. Furthermore, this thesis examines the impact of anthropogenic activities - including habitat loss, pollution, and climate change - on the genetic health and resilience of green sea turtle populations. By integrating genetic data with ecological and environmental parameters, this analysis explores the intricate interplay between genetic factors and environmental stressors, offering insights into the driving factors behind population decline. Ultimately, this research presents evidence-based conservation strategies for safeguarding sea turtle’s long-term survival, in the hope of contributing to their preservation and the maintenance of healthy marine ecosystems
Breath of the Wild: Analyzing Intraspecific Variation in Metabolic Rate Using Oxygen Respirometry in Daphnia magna
No full texthttps://rdc.reed.edu/v1/resources/336ba3ce-c861-4e1c-b170-0f24d18d38f5/thumb/128.jpgMetabolism is the biological system of chemical pathways that allow organisms to process nutrients and transform them into energy to sustain the body and build macromolecules. Because there are many working parts involved with metabolism and its chemical pathways, many factors that can influence the rate at which it takes place including the various mechanisms used to maintain homeothermy, variation in body size or activity levels, and abiotic factors like external temperature and stress. Many components of metabolic function have a genetic component and thus can vary among genotypes and evolve over time. Respirometry is a method used to measure oxygen uptake, and the exchange of oxygen and carbon dioxide within an isolated space over a period. In this study, respiration was measured in 105 Daphnia magna individuals across a total of 6 different genotypes of D. magna at two developmental stages. These genotypes originated from Finland, Germany, and Italy with 2 genotypes from each population. By comparing the metabolic rate across different genotypes of D. magna, we can build a stronger understanding of how much genotype variation impacts the metabolic rate and learn more about respirometry as a tool for understanding metabolism
Cellular energy allocation and phenotypic response to hypoxia in the aquatic crustacean Daphnia magna
No full texthttps://rdc.reed.edu/v1/resources/0bcde231-329e-44ec-9cda-095269ded8e2/thumb/128.jpgThis thesis examines the response of the ecological model organism Daphnia magna to chronic hypoxic conditions (2 mg/mL dissolved oxygen). Life- history, morphological, and physiological responses to hypoxic stress were examined for nine genotypes within three populations, looking for evidence of variation within this species in time to maturity, egg production, heart rate, and body size. A pair of common garden experiments was performed where Daphnia were reared under common conditions for three generations and then exposed to one of two treatments that differed in levels of dissolved oxygen (approx. 2 mg/mL vs 8 mg/mL). Body size and age at maturity were markedly decreased in individuals exposed to hypoxia, but there was no evidence of a decrease in egg production, which supports the theory of a trade-off favoring reproduction over increased growth in times of stress. Heart rate slowed significantly and total protein content increased in response to hypoxia, suggesting a compensatory mechanism that may in part reflect an increase in hemoglobin production. These results are consistent with previous studies that have examined the hypoxia response in Daphnia. Using Daphnia as a model for animal response to environmental stress can reveal the scope of the detrimental human effects on aquatic environments
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
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