published_or_final_version / Zoology / Master / Master of Philosophy

Thesis (M. Phil.)--University of Hong Kong, 1986.

Over the past thirty years, the presence of naïve notions, or alternate conceptions in a student population, have been consistently identified as playing a key role in the inability for students to understanding evolutionary theory (Brumby, 1979; Greene, 1990; Settlage, 1994; Ferrari and Chi, 1998). Ferrari and Chi (1998) document that most naïve notions associated with evolution education can be linked to mistaken ontological categorizations, where students associated evolutionary concepts with event process (where organisms determine implicitly or explicitly their destiny) instead of equilibration processes (ongoing, nondistinct actions) to which they belong. Research in the remediation of naïve knowledge (Ferrari and Chi, 1998; Bishop and Anderson, 1990) suggest the best way to overcome these “naïve notions” is by utilizing curriculum that (a) assess students misunderstandings, (b) present students with situations that cause them to contrast these misconceptions with current scientific theory, and to (c) gives students the opportunity to reflect on what they have learned, and explore this new information through guided learning activities. Based on this research, a teaching methodology that incorporated constructivist pedagogy with inquiry based methods, and framed the study of evolution within palentological context was tested on a classroom of college freshman during the spring of 2006. This approach was found to successfully identify and remove naïve conceptions from student understanding. Based on these results, this methodology was turned in to a distance-learning tool, consisting of a web based teaching module designed around fossil data from a subset of Kelley’s (1989) study of the molluscan fauna of the Chesapeake Group. The module mimics the classroom experience by replacing the teaching with interactive web pages, photographs, and video media detailing the processes utilized by the scientific community to identify, quantify, and interpret morphologic variation. Web module content is focused on the examination of gradual morphological change documented in two fauna of mollusks, and presented in a cross-disciplinary approach (geology, biology, and statistics) that expands the bounds of traditional science curriculum by bridging the gap between scientific research and science education. In a pilot study conducted to determine the ability for this module to be utilized in a science classroom, naïve notions were reduced by 10% when students utilized web material to examine evolutionary change. These results indicate that while effective at adding to the ability for educators to reduce student’s naïve understandings, the module is not effective at replacing traditional classroom instruction. The website can be found on the University of Vermont’s Perkins Museum of Geology homepage (http://www.uvm.edu/perkins/index.html), where visitors are asked to complete a survey in exchange for content use. The survey is part of an ongoing longitudinal study, the results of which will be quantified and used to improve and expand web content.

This study is divided into four sections beginning with a consideration of the effects of an hitherto undescribed coccidian parasite of the ovary of this bivalve on the dynamics of a particular population from Kames Bay, Millport, Isle of Cumbrae, Scotland. The parasite was found to bring about complete or partial castration of female Tellina tenuis but had no effect on males. The general biology of Tellina-tenuis is reviewed and discussed in relation to observations that were carried out over one year on the age structure, growth, density, reproduction and degree of parasitization of this bivalve. The population parameters were found to have changed little over the last fifty years. There was not found to be any significant change in the condition index that could be related to the destruction of the gonad by the parasite. This is the first description of a coccidian parasite of the ovaries of any marine mollusc. The second section describes the life cycle and developmental stages of the coccidian parasite. The parasite is believed to be monoxenous with sporogony and anisogamy orcurring in the ovary of the host. Endogenous stages were observed in the primary germ cells of the gonadal follicles. A diagnosis is presented based on the number of sprozoites per sporocyst and sporocysts per oocyst. The name Mcrocystis tellinovum (sp. nov. ) is proposed for this coccidian. The genus Merocystis belongs to the family Aggregatidae within the sub-order Eimeriorina of the order Eucoccidiorida. An ultrastructural study of both sexual and asexual stages is presented in support of this diagnosis. The third section of this study is an investigation of the observation that a large proportion of the Tellina tenuis examined histologically contained inclusion bodies within the secretory cells of the digestive gland. These inclusions were comprised of dense masses of pleomorphic mycoplasma-like organisms. The first part of this section describes the morphology and ultrastructure of these organisms and the histopathological effects on the host digestive gland. A description of the normal digestive gland iss-given including observations of the cyclic changes in appearance that take place in response to the influence of tidal rhythms. This is believed to be the first description of a mycoplasma-like organism from a marine invertebrate. The fourth section is concerned with a series of experiments to determine the nature of a virus seen in association with the mycoplasma-like organism. The virus was isolated from the host cells by density gradient centrifugation and its morphology was compared with a second virus isolated by Hill (1975) through the medium of a fish cell culture. It was found that these two viruses were quite distinct from each other. Attempts were made to propagate both viruses in an established cell line from the Atlantic salmon and the results are described and discussed.

Drilling predation presents a rare opportunity to quantify ecological and evolutionary interactions in the fossil record. To date, most of this research has been done on Late Mesozoic and Cenozoic deposits, and large-scale studies have focused on temporal rather than spatial patterns. However, drilling predation occurs throughout the entire Phanerozoic, and patterns in spatial variability may mask secular trends. These issues are addressed in a series of projects presented here. An extensive survey of museum specimens and bulk materials indicate that drilling predation in Late Paleozoic brachiopod prey is relatively rare (<1% of fossil specimens are drilled) but widespread and continuously present. The intensity of drilling predation on Late Paleozoic bivalve mollusks (this is the first quantitative report of this kind) is much higher than that seen for contemporaneous brachiopod prey, but lower than what is common for Late Mesozoic and Cenozoic mollusks. Drilling intensity varies significantly between taxa and across localities, (e.g., a sample of the Pennsylvanian brachiopod Cardiarina cordata produced an estimate of 32.7%, which is an intensity similar to that seen in Cenozoic mollusks and the highest yet reported for any brachiopod). However, data for the brachiopod genus Composita, which appears to be a preferred brachiopod prey in many Late Paleozoic assemblages, show that although this genus is subject to drilling predation continuously throughout its geologic range, the over all intensity is very low (less than 1%) and at no time does the intensity ever exceed 10%. Spatial variation in Miocene assemblages from Europe is shown to be on the same order as temporal variation throughout the Cenozoic. Significant variation in drilling intensity is also documented for the Paleozoic. This emphasizes the point that to fully understand patterns of predation through time, both spatial and temporal distribution must be considered. / Ph. D.

The artist discusses the concept, imagery, and research influences behind a body of work entitled What We Give, for the completion of her Bachelor of Arts Degree and undergraduate research for the Fine and Performing Arts Scholars branch of East Tennessee State University’s Honors College. The artist used this body of work to explore her personal relationships with the ocean, Aspergers, and information. Particularly, the artist’s pseudo-mystic beliefs about the ocean, her frustrations with her life struggles, and fascinations with scientific facts and libation vessels are discussed. Dysfunctionality is cited as the driving force behind the thought process of the project. Her work includes two sculptural vessels, rendered in ceramics and painted with house paint. The artist cites gastropod shells, ancient libation vessels, and contemporary artists Marcel Duchamp, Beth Cavener Stichter, and Alison Evans as inspirations.

Thesis (M.S.)--Rutgers University, 2008. / "Graduate Program in Ecology and Evolution." Includes bibliographical references (p. 73-77).

Orientador: Vera Nisaka Solferini / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-04T22:41:42Z (GMT). No. of bitstreams: 1 Andrade_SoniaCristinadaSilva_D.pdf: 14587285 bytes, checksum: 2a4ec18a37aa5d1a25489912a65439ec (MD5) Previous issue date: 2005 / Resumo: Uma das questões particularmente interessantes em Biologia é compreender o vínculo entre a ecologia e evolução das espécies. Avaliar a relação entre a capacidade de dispersão e a escala espacial na qual as populações diferem geneticamente é uma das formas de entender como esse vínculo é estabelecido. A variação espacial das freqüências alélicas em populações naturais pode ser resultado de isolamento por distância, história populacional ou seleção diversificadora. Análises populacionais em grande e pequena escala são relevantes para avaliar como essas freqüências podem variar espacial e temporalmente. O objetivo desse estudo foi investigar a distribuição da variabilidade em litorinídeos utilizando isozimas como marcador molecular. No primeiro capítulo, o padrão de desvio das proporções de Hardy- Weinberg foi analisado em três espécies de litorinídeos (Echinolittorina lineolata, Littoraria fiava e L. angulifera) em uma escala macrogeográfica ao longo da costa Brasileira (cerca de 4.000 km). Um teste de homogeneidade dentro das amostras mostrou que os valores dos FIS são, em sua maioria, heterogêneos. Este resultado exclui endogamia e efeito Wahlund como principais causas do excesso de homozigotos. Em todas as espécies, pelo menos um loco do sistema PGM apresentou valores homogêneos de desvio de Hardy- Weinberg em todas as amostras, sugerindo que essa enzima pode estar sob efeito de seleção natural ou em desequilíbrio de ligação com um loco sob seleção. No segundo capítulo, avaliamos a subdivisão em escala local em Littoraria flava a fim de testar se os desvios de Hardy-Weinberg podem ser explicados por estruturação genética em pequena escala, apesar de essa espécie possuir fase larval planctotrófica. As amostras foram coletadas em transectos horizontais no costão rochoso em três praias, três vezes em um período de cerca de um ano. Foi realizada uma análise hierárquica de 15 locos polimórficos comparando a estruturação de uma escala de 200 km em relação a uma escala de dezenas a poucas centenas de metros. Littoraria fiava apresentou maior estruturação dentro dos transectos e entre as diferentes coletas temporais do que entre as praias. Cerca de 18% dos testes de neutralidade de Ewens-Watterson apresentaram desvio significativo de neutralidade. Esses resultados sugerem um equilíbrio entre colonizações recorrentes e coeficientes seletivos variando no tempo e espaço sobre diferentes locos. No terceiro capítulo estão apresentados os resultados de uma avaliação do efeito do ambiente sobre a forma da rádula de L. fiava e L. angulifera. Além da caracterização da variação morfológica da rádula, foi realizado um experimento de transferência recíproca dos indivíduos entre o mangue e o costão. Nas duas espécies, foi observada menor variação na forma da rádula nos indivíduos coletados no mangue, indicando que cada ambiente tem um efeito diferente sobre esse caráter. No experimento de transferência, as rádulas de L. fiava apresentaram mudança de forma 40 dias após o início do experimento, apesar do tamanho da fita radular ser fortemente influenciado pelo substrato original (F6.22=17,13, p<0,001). Foram observadas mudanças na forma em diferentes intensidades, sugerindo plasticidade fenotípica da forma da rádula / Abstract: One of the main questions in biology is the link between a species ecology and its evolution. Evaluating the relationship between the geographical scale over which populations differ genetically and the species dispersal ability is a way to understand how this link is established. Spatial variation in allellic frequencies of natural populations may be explained by isolation by distance, population history or diversifying selection. Populational analyses at different scales are appropriate to evaluate how gene frequencies vary in time and space. The main goal of this study was to analyse the distribution of the genetic variability in littorinids using allozymes as molecular marker. In the first chapter, the pattern of heterozygote deficiency was evaluated in three littorinid species (Echinolittorina lineolata, Littoraria flava and L. angulifera) at a macrogeographic scale along the Brazilian coast (4,000 Km). A homogeneity test among loci showed heterogeneous FIS values in most populations. This result ruled out inbreeding and Wahlund effect as the main causes of departure of Hardy- Weinberg expectations. In the three littorinid species, at least one Pgm locus had homogeneous FIS values along all sampled populations, which suggests that this enzyme may have an important role in the fitness or may be linked to a locus under selection. In the second chapter, local-scale subdivision in Littoraria flava was investigated in order to test if Hardy- Weinberg deviations could be explained by micro-structuring, despite the planktotrophic larval phase. Samples were collected along horizontal transects in rocky shores of three different beaches, three times over a year. With this sampling design, and using 15 polymorphic allozymic loci, we searched for indications of any micro-scale or short-temporal subdivision in contrast with macrogeographic (200 Km) structuring. Littoraria flava samples presented significantly more structure within transects and along the temporal scale than at large-scale. Eighteen percent of the Ewens- Watterson neutrality test showed significant deviation of neutrality expectation. This suggested that there could be a balance among several recurrent colonizations by cohorts with different allelic frequencies, followed by a directional selection on different loci at different times and localities. In the last chapter, we assessed if environmental heterogeneity could affect radular form in L. flava and L. angulifera. We also made a reciprocal transfer experiment in natural conditions between mangrove and rocky shore locations, apart nearby 100 m. Individuals of both species from mangrove showed less variation in the shape of radula than those from rocky shores, implying in a different environmental effect in each species. In the natural transfer experiment, radulae morphology of L. flava individuals changed within 40 days, but the length of the radulae were strongly infIuenced by the original substrate (F6,22= 17 .13, p<0.00l). Changes in the shape had different intensities, suggesting that this trait could be subject to phenotypic plasticity / Doutorado / Genetica Animal e Evolução / Doutor em Genetica e Biologia Molecular

No description available.

Cultivated seafood is a potential alternative protein source that can address the rising global food demand with exponentially rising human population growth. Cultivated seafood is made by growing animal cells in vitro using stem cells for edible food, eliminating the need to raise the entire animal. A crucial first step in developing cultivated seafood is creating a well-characterized cell line that can continuously grow and differentiate into desired cell types. Due to difficulties in determining optimal primary cell culture conditions, no continuous cell lines of food-relevant mollusks have been established so far. This study used the adult Eastern Oyster, Crassostrea virginica, as a model bivalve to study the decontamination, cell dissociation, and culture conditions suited for mollusk adductor muscle cells. Oyster adductor (OAD) cells were obtained via tissue explant, mechanical and enzymatic digestion. The cells were routinely monitored using an inverted microscope for phase-contrast and fluorescence imaging. Culture vessels were coated with surface proteins such as fibronectin, laminin, matrigel, and poly-d-lysine to promote cell attachment. The tissue decontamination with Penicillin-Streptomycin (100 µg/mL), Amphotericin B (0.25 µg/ml), and algaecide solution (0.03%) was effective in controlling microbial growth. OAD cells grew best at lower nutrient levels in a one-to-one ratio of Lebovitz L-15 media and artificial seawater. Lower fetal bovine serum levels, 1-5%, provided a high number of cell attachments and consistent growth in combination with 1% adult oyster whole-body or larvae extract. The tissue explant method resulted in the optimal cell dissociation from the three methods, and proceeding cultures had attached cells surviving for up to 10 days. All the plate coatings promoted cell attachment, but fibronectin provided optimal cell attachment of OAD cells. Fibroblast-like, neuron-like, epithelial-like, and rounded cells were observed. Fluorescence cell staining confirmed the presence of cytoskeleton and nuclei in the OAD cell cultures. These advances in primary cell culture methods of OAD cells may be beneficial for establishing mollusk cell lines for cultivated seafood production. / Master of Science in Life Sciences / For sustainable seafood production, alternative sources of seafood proteins are essential in ensuring food security in the future. Cultivated seafood is an alternative protein source to address this rising food demand without the need to raise, farm, or slaughter animals. In developing cultivated seafood, self-renewing stem cells of the animal of interest are grown and made into edible products. A crucial first step in making cultivated seafood is understanding the growth conditions of the primary cells taken from animal tissue. Marine mollusk composes a significant part of seafood consumption, and developing cultured mollusks can address the growing food demand as a seafood alternative. However, there are many gaps in understanding the biological and physiological requirements of mollusk cells. No continuous, self-renewing mollusk cells of food-relevant species have yet been established. This study used the adult Eastern Oyster, Crassostrea virginica, as a model bivalve to study the tissue decontamination, cell dissociation, and culture conditions suited for oyster adductor muscle (OAD) cells. OAD cells were obtained via three cell dissociation methods. Cell growth was routinely monitored using an inverted microscope. Cell-surface proteins such as fibronectin, laminin, matrigel, and poly-d-lysine were used to promote cell attachment. The tissue decontamination was effective with Penicillin-Streptomycin, Amphotericin B, and algaecide. OAD cells grew best at lower nutrient levels in the one-to-one ratio of Lebovitz L-15 media and artificial seawater. Lower fetal bovine serum levels, 1-5%, provided a high number of cell attachments and consistent growth in combination with 1% adult oyster whole-body or larvae extract. Various cell morphologies were observed in the OAD cell cultures. Fluorescence cell staining confirmed the presence of cytoskeleton and nuclei in the OAD cell cultures. These advances in cell culture methods of OAD cells may be beneficial for establishing mollusk cell lines for cultivated seafood production.