The work included in this thesis aims at exploring the environmental sensitivity of benefits and costs of sexual selection through a combined empirical and theoretical effort, to increase our understanding of the impact of environmental change on sexually reproducing populations.Can sexual selection promote adaptation to novel environments? Sexual selection for good genes should accelerate adaptation by granting higher reproductive success to individuals of high genetic quality. However, sexual conflict is a frequent outcome of sexual reproduction and may often be detrimental to population fitness. Experimental evolution has shown that the role of sexual selection in adaptation is variable, because of a complex balance between the detrimental and beneficial effects described above.The present thesis is investigating the role of sexual selection in adaptation by focusing on the sex-specific strength of selection and the intensity of intralocus sexual conflict (IaSC) in ancestral and novel environments. The sex-specific strength of selection is a valuable proxy for the benefits of sexual reproduction, since a male-bias in selection caused by sexual selection should allow efficient purging of deleterious alleles with little impact on female fecundity and cost to population fitness.This thesis investigates both sex-specific selection and IaSC across benign and novel environments in two species of seed beetles, Callosobruchus maculatus and Acanthoscelides obtectus, and includes a theoretical model of the effect of environmental change on of sexual selection. The empirical part of my results indicates that, generally, selection at the adult stage is male biased but that this male bias may be reduced under stress, pointing towards reduced benefits of sexual selection under rapid environmental change. Additional simulations suggest that the frequency dependent nature of sexual selection alone could explain this trend. No empirical support was found for the reduction of IaSC under stress.It is becoming crucial today to understand the impact of environmental change on natural populations. This thesis brings new material adding to our understanding of the role of sexual selection within that particular issue. The outcome of sexual selection is dependent on a variety of mechanisms, such as good genes processes and sexual conflict, which are very likely to be dependent on ecological factors and specificity of the system studied. For that reason, carefully controlled experiments on laboratory systems and mathematical modelling are necessary steps that should ultimately lead to the study of similar questions in natural systems.

Living conditions of every organism are influenced by various factors at this time. Some of them have positive effect on organism, some negative. Basic condition for surviving is the ability to resist and adapt to changing metabolic and living conditions. Every single stress effect can lead to changes in metabolism but organisms have ability to develope sufficient mechanisms for stress response. Some of them are similar for all living organisms (enzyme production, endogenous primary stress metabolites) some of them are specific for certain organism or stress type. Cell stress response can be observed on different levels (proteomic, genomic, metabolomic). In proper conditions it can be used indrustrially. In this work, influences of various stress factors were studied. These factors were applied on selected organisms – carotenogenic yeast and plant materials. Yeast stress response was induced by osmotic and oxidation stress factors. Changes on proteomic level and in production of selected secondary metabolites were observed. Proteome was analyzed by 1D and 2D electrophoresis with subsequent analysis of proteins by mass spectrometry. Yeast strain Rhodotorula glutinis CCY 20-2-26 showed the best adaptation to stress factors, which was moreover accompanied by overproduction of carotenoids. This finding can be premise for next industrial production of carotenoids. In plant samples predominantly enzymes and metabolites involved in antioxidant response were studied.

Fluctuating asymmetry (FA) is commonly thought to be a predictor of environmental stress. However, the relationship between FA and established indicators for environmental stress has received little attention. In this study, 10-38 specimens of the freshwater fish Rhinichthys atratulus were collected from 15 natural populations under varying amounts of environmental stress. Asymmetry measurements in three bilateral characters of the specimens were used to investigate the relationship between FA and established indicators of environmental stress. Significant differences in the magnitude of FA were observed between sampling locations. However, the relationship between estimates of FA and established indicators produced varying results. The present study concludes with a discussion on the usefulness of FA as a bioindicator for environmental stress and implications for future studies.

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Orientador: Carmem Silvia Fontanetti Christofoletti / Banca: Elaine Cristina Mathias da Silva Zacarin / Banca: Carminda da Cruz Landim / Resumo: Embora os invertebrados sejam conhecidos pela grande facilidade de acúmulo de poluentes presentes em seu ambiente, e muitos serem utilizados como espécies sentinelas em estudos de biomonitoramento, pouco ainda é conhecido sobre o impacto de toxicantes sobre o sistema imune desses animais. Nesse sentido, os hemócitos desempenham um papel fundamental: estas células circulam livremente através da hemolinfa dos invertebrados e atuam no reconhecimento de materiais estranhos ao organismo, mediando e efetuando reações de defesa celular. Diferentes tipos morfológicos podem ser reconhecidos, mas ainda há controvérsia entre os pesquisadores sobre a exata classificação dos hemócitos, devido à diversidade de técnicas para preservação e observação dessas células. A classificação mais aceita atualmente agrupa os hemócitos em sete tipos principais: pró-hemócitos, plasmatócitos, granulócitos, esferulócitos, adipohemócitos, oenocitóides e coagulócitos. Por meio da utilização de técnicas histológica, histoquímica e ultra-estrutural, o presente trabalho objetivou caracterizar morfofisiologicamente os hemócitos circulantes na hemolinfa do diplópodo Rhinocricus padbergi, bem como aqueles encontrados por entre as células da camada de corpo gorduroso no intestino médio de animais expostos a substratos contendo diferentes amostras de lodo de esgoto, resíduo gerado nas Estações de Tratamento de Esgoto (ETEs). Este resíduo tem sido cogitado como um bom condicionador de solo em áreas degradadas e como um potencial fertilizante agrícola, apesar do risco de estar contaminado com patógenos e/ou metais pesados. A partir das análises realizadas, foram identificados três tipos morfológicos distintos de hemócitos circulantes na hemolinfa dessa espécie: pró-hemócitos, plasmatócitos e granulócitos (subtipos I e II). Também foram observadas células com características... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Although invertebrates are known for ease accumulation of pollutants present in their environment and several are used as sentinel species in biomonitoring studies, little is known about the impact of toxicants on the immune system of these animals. In this sense, hemocytes play an important role: these cells circulate freely through the hemolymph of invertebrates and act in the recognition of foreign materials to the organism, mediating and performing cellular defence reactions. Different morphological types are recognized, but there is still controversy among the researchers about the exact classification of the hemocytes due to the diversity of techniques for preservation and observation of these cells. Currently, the most accepted classification groups the hemocytes into seven main types: pro-hemocytes, plasmatocytes, granulocytes, spherulocytes, adipohemocytes, oenocytoids and coagulocytes. By histological, histochemical and ultra-structural techniques, the present study aimed to characterize morpho-physiologically the hemocytes circulating in the hemolymph of the diplopod Rhinocricus padbergi, as well as those found among the cells of the fat body layer of the midgut of animals exposed to substrates containing samples of sewage sludge, residue generated in the Sewage Treatment Plants (STPs). This residue has been considered as a good soil conditioner on degraded areas and as a potential agricultural fertilizer, despite the risk of being contaminated with pathogens and/or heavy metals. From the analyses carried out, it was identified three distinct morphological types of hemocytes circulating in the hemolymph of this species: pro-hemocytes, plasmatocytes and granulocytes (subtypes I and II). It was also observed cells with intermediate characteristics between pro-hemocytes and plasmatocytes, suggesting a probable cellular differentiation in the hemolymph... (Complete abstract click electronic access below) / Mestre

This dissertation presents the results of an investigation of rural households’ ability to adapt to changing environmental and climatic conditions. It presents soil degradation arising from worsening soil erosion, leaching, depletion of nutrients due to years of uninterrupted cultivation and low levels of use of fertilizers; uncontrolled deforestation leading to loss of biodiversity; and climate variability seen through longer dry seasons as well as delayed and falling levels of precipitation as key issues leading to the vulnerability of households in Kakemega District in Western Province of Kenya. An enquiry has been made into the adaptation strategies of the rural households and a composite household adaptive capacity index (HACI) developed which is then used in hypothesis testing. Despite a situation laden with serious soil degradation and fears that credit taken by rural households often end up in low-return necessity-based enterprises or in consumption expenditure, the dissertation shows that the use of credit positively contributes to the HACI as does regular and optimal use of farm inputs. Diversification into non-agricultural activities, on-farm planting of trees and migration with remittances were some of the adaptation strategies observed among households with relatively high adaptive capacity indices while a secondary school level of education alongside the possession of non-land and non-livestock assets were key factors clearly associated with high adaptive capacity indices. Regarding adaptation decision making, the household head was observed to be the single most important actor in a process which was often characterized by authoritarianism. The household head’s level of information or awareness of environmental changes and open options proved to be important for adaptation. It was revealed that membership to groups and networks as well as government and NGO-activities were the most important factors in informing the household heads. Given small land sizes and a high incidence of other negative shocks, household heads tended to adopt and implement only tried and tested adaptation actions. During the study behind this dissertation, pioneers in the implementation of new strategies were observed to be better informed household heads or beneficiaries of incentives from the promoters of such strategies. Newer efforts aimed at the promotion of adaptability would therefore gain wider acceptance and adoption if preceded by a pilot phase carefully designed to include committed opinion shapers who would provide a demonstration effect. / In dieser Dissertation wurden ländliche Haushalte bezüglich ihrer Anpassungsfähigkeit an den Umwelt- und Klimawandel untersucht. Desweiteren geht die Dissertation unter anderen der Frage über Strategien nach, die von ländlichen Haushalten angesichts der Auswirkungen von Umweltproblemen eingesetzt werden. Die Feldforschung wurde unter den Haushalten im Kakamega Distrikt in Kenia getätigt. Eine Abnahme der Bodenproduktivität ist durch Erosion, einem Auslaugen und einer ununterbrochenen Kultivierung in Kakamega entstanden. Desweiteren führt eine unkontrollierte Abholzung mit resultierendem Verlust von heimischer Flora und Fauna sowie längeren Trockenperioden mit verspätetem Einsatz von Regenfällen und einer damit verbundenen Niederschlagsminimierung zu einer schwierigen Lebenssituation für die ländlichen Haushalte, die hauptsächlich durch Landwirtschaft ihre Existenz sichern. Diese Situation (gekennzeichnet durch Abholzung, Verlust der Artenvielfalt, Verminderung der Bodenqualität und unregelmäßige und wechselhafte Niederschlag) wird in dieser Arbeit als Umweltwandel (Environmental Change oder Environmental Stress) bezeichnet. Es konnte unter anderem als eines der Ergebnisse der Arbeit festgestellt werden, dass die ländlichen Haushalte aufgrund schlechten Bodens, unkontrollierten Abholzungen, längeren Trockenzeiten und sinkenden Niederschlagsmengen sehr anfällig sind. Durch den Einsatz des zusammengesetzten Haushalt-Anpassungsfähigkeitsindex (Household Adaptive Capacity Index = HACI), der im Rahmen dieser Dissertation entwickelt wurde, konnten die Bedenken gemindert werden, dass Kredite, die an ärmeren ländlichen Haushalten vergeben werden, oft für Notgründungen und Konsumausgaben eingesetzt werden. Es hat sich herauskristallisiert, dass die optimale und regelmäßige Nutzung von Düngemitteln sowie der Einsatz von Krediten, die HACI positiv beeinflusst. Als weitere Ergebnisse konnte beobachtet werden, dass Haushalte mit höheren Anpassungsfähigkeitsindexen Anpassungstrategien wie Diversifizierung in nicht-agra Aktivitäten, Aufforstung und Migration verwenden, und, dass ein Sekundarschulabschluss und der Besitz von Wirtschaftsgütern mit hohen Haushalt-Anpassungsfähigkeitsindexen assoziiert sind. Zum Anpassungsentscheidungspozess konnte festgestellt werden, dass Haushaltoberhäupter, die wichtigste Akteure sind. Entscheidungsweisen dieser Haushaltoberhäupten lassen oftmals autoritäre Züge erkennen. So entscheiden die Haushaltoberhäupter häufig auch, in welcher Art und Weise Haushalte sich anpassen dürfen. Von daher ist das Wissen des Haushaltoberhauptes über die herrschenden Umweltbedingungen und die offenen Strategien oder Handlungspielräume von Bedeutung. Die Feldforschung zeigte, dass die Zugehörigkeit zu einzelnen Gruppen sowie die Bemühungen von der Regierung und den Nichtregierungsorganisationen wichtig für die Erhöhung des Wissens von Haushaltoberhäupten sind. Da der durchschnittliche Haushaltgrundstückbesitz sinkt und andere negative Ereignisse wie Krankheit und Tod zunehmend Angst verbreiten, setzen Haushaltsoberhäupter häufig nur dann empfohlene Strategien zur Anpassung ein, wenn sie beispielsweise einen Erfolg bei einem Nachbar verzeichnen können. Oftmals werden Anpassungsstrategien auch bei finanziellen Anreizen, zum Beispiel von Förderern, umgesetzt. Es würden mit hoher Wahrscheinlichkeit mehr Anpassungstrategien von ländlichen Haushalten umgesetzt werden, wenn diese Strategien Pilotprojekte beinhalten würden, die Haushalten das Zusammenspiel von Anpassung und Ernteertrag präsentieren.

The biogeographic distribution of organisms is determined by physiological characteristics that enable a population to persist in a specific location. Global climate change effects are anticipated to increase the physiological stress experienced by organisms. Consequently, it is important to understand physiological responses to environmental stress and the mechanisms used by animals to cope with variable conditions. I investigated the physiological response to environmental stress in two species of mussel from New Zealand, Perna canaliculus and Mytilus galloprovincialis, using quantitative PCR and ecological field experiments. A series of laboratory and field experiments were done to manipulate stress levels and the expression levels of three heat shock protein genes (hsp24, hsp70, hsp90) were measured. A transcription regulatory gene (elf2) and a cell cycle regulatory gene (tis11d) were also measured. The dynamics of stress response gene expression in response to acute stress and gene expression changes in the natural population due to varying forms of environmental stress were tested. Between-zone translocations of different sized M. galloprovincialis and P. canaliculus were done at two sites in both east and west regions of the South Island of New Zealand. Site was found to be the most important factor in stress response. Apparent low food and high exposure stress interacted to create the particularly elevated stress response at the Timaru site. The adaptive ability of mussels transplanted between sites with varying environmental conditions was also tested. Results suggest that acclimation may be limited under stressful conditions. Furthermore, I found that P. canaliculus, the predominantly low-zone species, had a lower stress response than M. galloprovincialis, which was contradictory to predictions. The investigations described in this thesis suggest that interactive effects of abiotic stress and food limitations are particularly challenging for animals. With the severity of climate change scenarios predicted, changes in water quality and aerial and seawater temperature suggest mussel populations are likely to be negatively affected in the future. This work also illustrates the great potential to utilise molecular techniques for analysis of physiological processes of non-model organisms in a real-world setting.

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