A three year study on Daphne Major island, Galapagos, describes the ecology and morphology of a simple Geospiza community. The four part thesis discusses the breeding and feeding ecology of two Daphne finches; G. fortis is a generalist adapted to a variable environment, and G. scandens is an ecological specialist experiencing a more stable environment. The measurement, growth, allometry, and multivariate properties of seven external morphological characters are described. The repeatabilities and heritabilities of the seven characters and principal component scores are large. Relations between the unusual intermediate-sized Daphne G. fortis phenotype and the Daphne environment are examined. Four hypotheses for the intermediacy, including genetic drift, hybridization, local adaptation, and competition are suggested, with evidence found to support parts of each except genetic drift. An episode of intense directional natural selection is documented, and Lack's character release explanation of the Daphne G. fortis phenotype is revised.

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This study developed a robust technique for the assessment of morphometric differences among overwintering northern fish populations. Arctic charr were sampled soon before the freeze-up and just after ice break-up at two subarctic Quebec lakes. A homogenous sample of 397 fish was used. Regression analyses of the length-weight relationships and their derived condition indices were insufficient, due to their inherent limitations, to recognize the differences between sampling groups. A series of multivariate analyses (canonical, stepwise and discriminant analysis), based on eleven morphometric characters of the fish, provided a better assessment. The analysis recognized the distinctions between sampling groups, correctly classified 70-100% of the fish into their appropriate groupings, and indicated that body height measured at the anal opening was the most discriminatory variable. Landmark variables related to shape differences were effective in discriminating fish according to their lake of origin, whereas length and weight variables, which closely reflected the size differences, were better at distinguishing seasonal changes. The study provides a simple, efficient assessment method based on phenotypic variations to explain different survival strategies, and the associated life history traits, adopted by fish.

<p> This research examines the evolution, phylogenetic distribution, and functional explanations for a peculiar and often overlooked character seen in birds, herein called tracheal and esophageal displacement. Of special interest to this study is examining whether the trait was present in non-avian theropod dinosaurs. This study found that essentially all birds are characterized by a laterally displaced trachea and/or esophagus. The displacement may occur gradually along the neck, or it may happen immediately upon exiting the oropharynx. Displacement of these organs is the result of a heavily modified neck wherein muscles that create mobility restrictions in lizards, alligators, and mammals (e.g., <i>m. episternocleidomastoideus, m. omohyoideus,</i> and <i> m. sternohyoideus</i>) no longer substantially restrict positions in birds. Rather, these muscles are modified, which may assist with making tracheal movements. </p><p> An exceptionally well-preserved fossil theropod, <i>Scipionyx samniticus </i>, proved to be paramount. Its <i>in situ</i> tracheal and esophageal positions and detailed preservation (showing the hallmarks of displacement including rotation, obliquity, a strong angle, and a dorsal position in a caudad region of the neck) demonstrate that at least some theropods were characterized by tracheal and esophageal displacement. Ultimately, the presence of the trait correlates with a highly flexible neck, allowing slack and permitting for the organs to save length as they avoid the long curves of the S-shaped neck.</p>

Analysis of organic form begins not with plants but with the problem of Cartesian dualism. Inadvertently, its effect was to remove God from the natural world, thus opening the way to atheism. In the seventeenth and eighteenth centuries, this was refuted by stress on God's active role in nature. The presence and operation of his intellect was equated with life as the primary force in the natural world. Later natural philosophy developed a theory of power which was also equated with life and mind. The subject of Wordsworth's two-part Prelude is the relation of the mind to this life or permeating spirit, and the epistemological uncertainties which it entails. While proposing a view in which the individual is integrated into the totality, the poem also raises the problem of how the individual can also be contradistinguished from it. Blumenbach, under whom Coleridge studied in 1798-99, proposed a different theory of life in which it was defined as a nisus formativus, or inner self-generating power, which creates the form of the living body. Coleridge developed this into a theory of life as individuation, which resolved the opposition of the infinite and the individual. Study of Kant also showed how the nisus formativus could be allied to a theory of method based on a priori cognitive structures. The expansion of The Prelude in 1804 is related to Wordsworth's identification of the self, as the inner principle of life, with the a priori guiding Idea of his poem. Imagination, the "co-adunating Faculty," links the two together. Wordsworth's related theory of poetry views mind and language as integrated in the same way as mind and body, life and matter, and God's mind and nature. Together, these provide the basis for an understanding of the structure of the poem, and, in particular, its "fall."

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The origin and maintenance of phenotypic variation has generated considerable interest among students of functional morphology, sexual selection and behavioral ecology. In particular, hybridization has been suggested as a phenomenon which may generate novel phenotypic variation. In this dissertation I focus on the Xiphophorus birchmanni - X. malinche hybrid system to assess the role of hybridization in altering behavioral, morphological, sexual and non-sexual traits. I determine the relationship between the sword sexual ornament and body condition to support previous work which suggests that the sword is an inexpensive means to increase apparent size. My findings support the prediction that, while body size is condition-dependent, the sword is not. I show a trend toward hybrid populations displaying increased phenotypic variance and reduced phenotypic integration in sexual ornaments and body size. These findings provide evidence for a potential answer to a central question in the study of sexual selection, that of reduced genetic and phenotypic variance in sexual ornaments as the result of persistent direction selection generated by female choice. I take advantage of reduced phenotypic integration in hybrids allowing the evaluation of locomotor performance across a broad range of multivariate trait values. Sexual ornaments did not impair swimming performance per se. Rather, the sword negatively affected performance only when paired with a sub-optimal body shape. I evaluated how natural hybridization changes the relationship between boldness and anti-predator response. In poeciliid fishes, bold individuals have increased survival in the presence of predators. This non-intuitive observation may result from bold individuals being more likely to engage in anti-predator behaviors. Counter to my prediction, bold individuals were less likely to perform a fast-start response to a predator threat. This correlation was consistent among populations and species but was only significant in hybrids. My findings suggest that hybridization could influence correlations between behavioral traits in a manner similar to that documented for morphological traits.

Thesis (Ph.D.)--Kent State University, 2007. / Title from PDF t.p. (viewed Mar. 5, 2009). Advisor: C. Owen Lovejoy. Keywords: temperature, bone growth, Allen's Rule, skeletal morphology, limb proportions, environmental effects on bone growth. Includes bibliographical references (p. 157-176).

Thesis (Ph.D.)--Victoria University of Wellington, 2008. / Includes bibliographical references.