This Ph.D. dissertation integrates stable isotope and trace element geochemistry in modern and fossil gastropod shells to study low-latitude marine paleoenvironments. First, stable isotopes (delta18O and delta13C) and Sr/Ca ratios are used to examine low-latitude temperature and salinity variations recorded in Plio-Pleistocene (3.5-1.6 Ma) fossils from western Florida during periods of high-latitude warming and "global" cooling. The middle Pliocene Pinecrest Beds (Units 7 and 4) and the overlaying Plio-Pleistocene Caloosahatchee Formation generate significantly different delta18O-derived paleotemperatures but identical Sr/Ca ratios. High delta18O values, together with low delta13C values and brackish fauna, indicate that Unit 4 was deposited in a lagoonal environment similar to modern Florida Bay. In contrast, relatively low delta18O and high delta13C values in Unit 7 and Caloosahatchee Formation represent deposition in an open-marine environment. The observed Unit 7 and Caloosahatchee paleotemperatures are inconsistent with middle Pliocene warming event, but consistent with the Plio-Pleistocene cooling trend. To quantify modern upwelling and freshening signals and contrast these signals between the tropical eastern Pacific (TEP) and southwestern Caribbean (SWC), methodologies are developed for reconstructing seasonal upwelling and freshening patterns from modern tropical gastropod shells from Panama using: 1) paired oxygen and carbon isotopic profiles and delta18O-delta13C (delta-delta) correlations, and 2) deviation from baseline delta18O values that represent conditions free of seasonal upwelling or freshening influences. Shell delta18O values normalized to the baseline faithfully record modern conditions of little or no upwelling in SWC and Gulf of Chiriqui, and strong upwelling in the Gulf of Panama, as well as strong freshwater input in most areas. The baseline and delta-delta methods are applied to identify and quantify changes in upwelling and freshening in the Neogene TEP and SWC seawaters associated with the final closure of Central American Isthmus. The records reveal significant upwelling in late Miocene SWC and mid Pliocene TEP waters, strong freshening in SWC waters from 5.7-2.2 Ma, and minimal seasonal upwelling and/or freshening variations in Plio-Pleistocene SWC waters. The reconstructed paleotemperatures agree with the global cooling trend through the late Miocene, but lack evidence for middle Pliocene warming or late Neogene global cooling.

Thesis (Ph. D.)--Florida State University, 2004. / Advisor: Cathy W. Levenson, Florida State University, College of Human Sciences, Dept. of Nutrition, Food and Exercise Sciences. Title and description from dissertation home page (viewed Jan. 30, 2006). Document formatted into pages; contains viii, 94 pages. Includes bibliographical references.

Knowledge of environmental history is important for the management and conservation of fish populations. Multiple methods to tag or mark fish have been developed (e.g., radio transmitters, coded wire tags, PIT tags, genetic markers), however, each of these methods has limitations. Naturally occurring and artificial chemical markers in otoliths have recently been used to determine natal origins and environmental history of fishes in both marine and freshwater environments and are not subject to the shortcomings of conventional tagging methods. However, few studies have evaluated the application of fish fin rays as a non-lethal alternative to fish otoliths as a recorder of individual fish environmental history. Therefore, I evaluated the application of artificial and naturally occurring chemical markers in fish fin rays as tracers of individual environmental histories. Specifically, I sought to determine 1) if age-0 lake sturgeon pectoral fin rays could be marked by immersion in strontium carbonate (SrCO3) enriched with the stable isotope 86Sr (86SrCO3), 2) whether natural differences in otolith and fin spine chemistry are present in catfish species collected from the Mississippi River basin, and 3) whether natural differences in fin ray chemistry are present in smallmouth bass from different rivers and streams in northern Illinois. Results from the first objective indicated that age-0 lake sturgeon were marked with 83% success when reared in water enriched with 100 µg/L of 86SrCO3, compared to control fish, and mark retention was maintained for at least 120 d following the labeling period. Results of the second objective indicated that both catfish otolith Sr:Ca, δ18O, and δ13C and fin spine Sr:Ca differed among sites, reflecting geographic differences in water chemistry at source locations. Both structures classified fish to their environment of capture with a high degree of accuracy, except in the Middle and Lower Mississippi Rivers where many recent immigrants appeared to be present. Similarly, smallmouth bass fin ray core Sr:Ca differed among sites, reflecting previously documented differences in water chemistry among streams and rivers in northern Illinois. Classification accuracy of smallmouth bass to their environment of capture based on fin ray Sr:Ca was variable, as some rivers had similar water chemistry signatures. The use of artificial chemical marks in fin rays will be useful when marking small fish that may not respond well to physical tags, when non-lethal recovery is desirable, and to distinguish between multiple batches of stocked fish (i.e. to evaluate factors such as stocking location and timing, fish size, and when fish may become interspersed into the existing population). Natural chemical signatures in pectoral fin rays or fin spines may provide a non-lethal alternative to otoliths for gathering information on environmental history (e.g. stock mixing, recruitment sources) of smallmouth bass and catfishes, consistent with recent demonstrations of this technique's effectiveness in other fish species. Ultimately, the use of artificial and naturally occurring chemical marks in fish fin rays provides a non-lethal alternative method to evaluate the environmental history of all life stages of fish

The emergence of parasite resistance to most classes of anthelmintics, as well as the difficulty of controlling Haemonchus contortus infection, are among the main problems faced in the sheep farming industry. Alternative and/or auxiliary control methods are essential to minimize the losses caused by H. contortus infection. The inflammatory process caused by parasitic infection increases the production of reactive species, when produced in excess exacerbate the damage caused by such infections. Given the importance of alternative control methods and the role that zinc plays in the activity of enzymes associated with the oxidative profile, the aim of the present study was to assess the action of a source of parenteral zinc (edetate zinc) in oxidative profile of lambs infected by H. contortus. For this, 24 lambs were divided into four groups: Group I - uninfected animals; Group II - uninfected animals and treated with 3 mg of edetate zinc kg-1 body weight; Group III - animals infected with 12000 larvae in the third stage of H. contortus; and Group IV - animals infected with 12000 larvae in the third stage of H. contortus and treated with 3 mg of edetate zinc kg-1 body weight. The lambs were monitored for 38 days, during which time feces and blood samples were collected on day zero and at seven days intervals. Serum samples from animals with an oxidative profile were analyzed by quantifying the total antioxidant capacity (TAC) and the total oxidation status (TOS). The eggs per gram (EPG) in feces were also counted. On the last experimental day, three animals from each group were euthanized and the quantity of H. contortus adults in the abomasums was determined. The results showed that oxidative stress in the animals from group IV was lower than in Group I 17 days after treatment with edetate zinc. Furthermore, 24 days after treatment, group IV showed a reduction in oxidative stress in relation to group III. No interference in the parasite load was recorded. These results show that treatment with edetate zinc could assist in reducing the damage caused by oxidative stress, but does not reduce infection with H. contortus. / O surgimento da resistência parasitária à maioria das classes de anti-helmínticos e, consequentemente, a dificuldade no controle do Haemonchus contortus, tornou a infecção por este parasito um dos principais entraves da criação de ovinos. Para minimizar as perdas causadas pelo H. contortus, métodos de controle alternativo e/ou auxiliar tornaram-se fundamentais. O processo inflamatório causado pela infecção parasitária aumenta a produção de espécies reativas, as quais quando produzidas em demasia agravam os danos causados por essa infecção. Visando a importância de métodos alternativos e sabendo que o zinco tem importante papel na atividade de enzimas ligadas ao perfil oxidativo o objetivo desse trabalho foi avaliar a ação de uma fonte de zinco parenteral (edetato de zinco) no perfil oxidativo de cordeiros infectados por H. contortus. Para isto 24 cordeiros foram divididos em quatro grupos, sendo Grupo I - animais não infectados, Grupo II animais não infectados e tratados com 3 mg de edetato de zinco, via subcutânea (SC) kg-1 de peso vivo, Grupo III animais infectados com 12000 larvas de terceiro estágio de H. contortus e Grupo IV animais infectados com 12000 larvas de terceiro estágio de H. contortus e tratados com 3 mg de edetato de zinco, via subcutânea (SC) kg-1 de peso vivo. Estes cordeiros foram acompanhados por um período experimental de 38 dias, sendo realizada coleta de fezes e sangue em intervalo de sete dias a partir do dia zero. Nas amostras de soro foi analisado o perfil oxidativo, através da quantificação da capacidade antioxidante total (TAC) e do status de oxidação total (TOS), e na de fezes a contagem de ovos por grama de fezes (OPG). No ultimo dia experimental, três animais de cada grupo foram submetidos à eutanásia e então realizada a contagem do número de H. contortus adultos no abomaso. Os resultados demonstraram que 17 dias após o tratamento com edetato de zinco o estresse oxidativo dos cordeiros do grupo IV foi inferior aos do grupo I e que 24 dias após o tratamento o grupo IV apresentou redução no estresse oxidativo em relação ao grupo III, porém sem interfere na carga parasitária. Demonstrando que o tratamento com edetato de zinco pode auxiliar na redução dos danos causados pelo estresse oxidativo, embora não reduza a infecção por H. contortus.

The Sr/Ca ratios in calcium carbonate fossils are used by the paleooceanographic community to infer past environmental conditions, such as sea surface temperature and ocean chemistry. The processes of biogenic calcification that produce these chemical signatures are complex and not fully understood, however, and vital effects are known to affect the trace element composition of the CaCO₃ biomineral products. The recent discovery that calcifying organisms produce amorphous calcium carbonate (ACC) as an intermediate phase during the crystallization process calls into question whether this pathway to mineral formation affects trace element distributions in the final product. This non-classical mineralization process raises the question of whether the Sr/Ca ratios of the final products are dependent upon temperature. That is, what is the temperature dependence of Sr/Ca ratios in calcite produced via ACC compared to the measurements obtained from calcite grown by the classical process in laboratory experiments and from biogenic settings. The goal of this study is to determine the effects of solution chemistry and temperature on the Sr composition of ACC and resultant crystalline CaCO₃. Two types of experiments were designed: First, experiments were conducted to synthesize inorganic ACC in a batch reactor for a suite of selected chemical compositions and allowing this intermediate phase to transform into calcite in the reactant solution. In a second series of experiments, ACC was precipitated by a flow-through method to compare results to the batch reactor experiments. The experimental design focused on determining the Sr/Ca ratio and Sr distribution coefficients (KD, Sr) of the amorphous and final crystalline products. Mg/Ca ratios of 5/1 were found to suppress Sr uptake into ACC by a factor of 25% when the initial Sr solution had concentration of one millimolar. ICP-AES data collected across the 18° to 30°C range showed that the Sr/Ca ratio in both ACC and the resultant calcite was independent of temperature. Upon transformation, the Sr/Ca ratios of both the ACC and calcite product were found to be similar, showing that Sr/Ca ratios were independent of the transformation process. Analysis of the data determined KD, Sr values of 0.564(±0.006) for ACC and 0.466(±0.009) for the resultant calcite in the 18-30°C temperature range. The findings show that the Sr/Ca ratios of ACC and the transformed calcite are independent of temperature. However, the corresponding KD, Sr values exceed those reported for calcite grown by classical processes by an order of magnitude. The findings for the inorganic calcite yield KD, Sr values up to four times higher than those found in biogenic calcites. Because the findings of this study show that Sr/Ca is independent of temperature, this study calls into question whether previously reported Sr/Ca measurements in biogenic calcites should be revisited. It is plausible that biological factors have a significant influence on trace element incorporation into biogenic calcite. Vital effects, such as the influence of macromolecules during the ion uptake process, may regulate the apparent Sr/Ca versus temperature trends observed in marine paleontology. Higher KD, Sr values in marine calcifiers may indicate that organisms use the non-classical mineralization pathway in whole or in part. Future studies of trace element incorporation in calcifying species should consider the pathway to mineralization in tandem with interpretations of environmental controls on distribution coefficients. / Master of Science

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Tooth enamel is among the most durable substances in the human body and as such has high recoverability in forensic anthropology cases. Its crystalline hydroxyapatite matrix has a slightly variable chemical composition which incorporates biologically available trace elements. The trace elements are derived from an individual's diet and the water he or she consumes during the period of enamel formation. As a result, trace element profiles of enamel can reflect the geology, pollution, and certain cultural dietary factors of the area in which the individual resided during this period. This research examines a sample of teeth with known demographic information from the Antioquia Modern Skeletal Reference Collection in Medellin, Colombia. A sample set of 75 teeth from 61 individuals born in areas throughout northwestern Colombia were analyzed using laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS), a minimally destructive, semi-quantitative technique. Analysis was performed at the Center for Archaeology, Materials, and Applied Spectroscopy (CAMAS) at Idaho State University. 33 elements were analyzed in the sample. Nonparametric methods were used to assess the relationship between elemental profiles and region of origin. Sr, Mo, Ag, Ba, Eu, and Tm concentration profiles were found to vary among regional groups. Al, Ni, Cr, Mn, Co, Sr, Cd, Sb, Sm, Eu, and U were found to predict region of origin. Differences in municipality were classified with 72% accuracy, variation across the department of Antioquia was classified with 67% accuracy, and the age of the geologic substrate was classified with 67% accuracy. The results suggest that trace element analysis of permanent tooth enamel may be of some use in estimating an individual's region of origin in forensic anthropological contexts. Further research with both larger sample sizes and more geographic variation is necessary.

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