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Item Modelagem de nicho em espécies de plantas do Cerrado e distribuição espacial da variabilidade genética(Universidade Federal de Goiás, 2010-09-30) CAVALCANTI, Fábio André Gomes S; NABOUT, João Carlos; http://lattes.cnpq.br/3335844675689429; TELLES, Mariana Pires de Campos; http://lattes.cnpq.br/4648436798023532Ecological and evolutionary factors may explain the patterns of intrapopulation variability across the geographic distribution of a species. More suitable habitats, in ecological terms, allow the survival of greater number of individuals, which increases the genetic variability in the population, while in less suitable habitats, because of smaller population size, individuals have lower reproductive rate and higher mortality rate, these populations may lead to loss of genetic variability and extinction. In this context, the goal of this study was to use meta-analysis techniques to relate the genetic variables (observed and expected heterozygosity and inbreeding) with the models of potential geographical distribution of nine species of Cerrado plants. In addition, genetic variables were correlated with human occupation at sites where plant species occurred. For this work were used 11 studies, in which genetic data were obtained from literature and the points of occurrence in databases and also the literature. Five species distribution models (Maxent, Mahalanobis, Euclidian, Domain and Bioclim) were used and then superimposed on a combined basis (i.e Ensemble forecasting). Were performed Pearson correlations between genetic variables and environmental and human occupation. The coefficients of these correlations were matched using a meta-analysis to find a general correlation studies. The correlations between genetic variables with the ecological variable (i.e environmental suitability) and human occupation tended to zero. Although significant values have been obtained with studies of isozymes for the human index (r = 0.57 P = 0.01) related, independent, with the observed heterozygosity. A positive relationship exists between the human and the expected heterozygosity index (r = 0.27, P = 0.01) was found in the relationship between all the studies together. We also found significant values for studies with isoenzymes in ecological indices (r = 0.39, P = 0.04) and human (r = 0.50, P = 0.01) and the distance from the center of the potential distribution species (r = -0.44, P = 0.05) between the expected heterozygosity. The results of the mean effect between heterozygosity and occupation indices suggest that the plants were evaluated in studies with isozymes show a high heterozygosity in places with high human occupation. Due to the occupation of the Cerrado be intense, but recent, and due to plant species have long life cycles of species populations may not yet be genetically structured in this new landscape of the Cerrado. The results of studies with isozymes, correlation between heterozygosity and distance from the center of potential distribution of species have confirmed our predictions. Plants tend to lose more distant genetic variability by having a lower population density. The relationship between habitat suitability and distance from the center indicated a relationship is also negative (r = -0.35, P <0.05), suggesting that adequacy is also lower in peripheral regions. In general, the methodology used to conduct preliminary assessments of the distribution of the population structure of Cerrado plants related to genetic variables proven very useful and practical.Item Transformando tropeços em passos de dança: o uso de espécies exóticas para estudos biogeográficos(Universidade Federal de Goiás, 2008-02-27) LIMA JUNIOR, Dilermando Pereira; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351The establishment of exotic species is known for the negative impacts it causes. However, it can be used as models to study the ecological and evolutionary causes of biogeography patterns and access whether the niche conservatism is the determinant of the species limits distribution. The main purpose of this study is to evaluate the difference between pools of exotic fish species in biogeographical regions of the world based on the theories of Niche Conservatism and Evolutionary Dynamics of Latitudinal Gradients of Diversity. We found a strong tendency of the niche conservatism with exotic fishes, but no phylogentic structures of the invaders fishes were found. Therefore, predictive models that purpose to evaluate the potential invasion of fishes has to, include extrinsic factors as climatic conditions, propagule pressure, environmental disturbance, human use and intrinsic factors as parental care and body size of the species.Item Avaliação de modelos de distribuição de espécies e sua aplicação na conservação da onça-pintada (Panthera onca)(Universidade Federal de Goiás, 2010-11-19) TÔRRES, Natália Mundim; MARCO JÚNIOR, Paulo de; http://lattes.cnpq.br/2767494720646648; DINIZ FILHO, José Alexandre Felizola; http://lattes.cnpq.br/0706396442417351Recently, Species Distribution Modelling (SDM) has been widely used as base for several types of analyses, including evaluations of climate changing impact on species distribution and conservation strategies settlement. This methodology enables the prediction of potential geographic distribution based on species ecological requirements, extrapolating data from known occurrences to unknown areas. There is a wide variety of methods which presents different capabilities to synthesize the significant relationships between species data and the environmental variables used as preditors. These variations are consequences of a series of factors that influence model s performance, such as species characteristics, the kind and quantity of data available, and the scale of the analyses. In this study we adopted the jaguar as a model to evaluate eleven SDM. It was evaluated the spatial autocorrelation effects between presence records on model s performance, and the relationship between environmental suitability obtained through these methods and jaguar population density. The obtained results were used as a basis for the evaluation of jaguar conservation topics, including analyses of how global climate changing and land use predictions will affect its distribution and evaluation of protected areas system in maintaining suitable areas for species occurrence in the future. It was demonstrated that depending on the model applied, the species data amount can be more influential than the spatial autocorrelation between presence points, and that the expected positive relationship between model-based suitability estimate and jaguar density was found only for four SDM, but always with a low coefficient of determination showing a weak data fitness. The analyses also showed that suitability values inside protected areas are greater than expected by null model, and this difference tend to increase with the global climate change scenario evaluated, demonstrating that it is not expected that environmental suitable areas for jaguars will shift out from the existing protected areas. Considering future predictions, the main conclusion is that some regions which must go through an environmental suitability increase for jaguar occurrence in the future will be converted from natural vegetation to agricultural land, indicating that the opportunities for jaguar s effective conservation actions are daily becoming more restricted, in such a way that the calling for a proactive conservation approach is urgent.